JPH05326024A - Layered gastight metal oxide-hydrogen secondary battery and battery group system and charging method thereof - Google Patents

Abstract

PURPOSE:To lengthen charge-discharge cycle life, and heighten reliability and safety by detecting a battery temperature and thereafter opening/closing a charging circuit or increasing/decreasing charge current interlocking with a charge voltage detector and/or a timer. CONSTITUTION:A temperature detector 12 is set to an assigned temperature, and charge current is allowed to flow into a module battery through a charger 13. The temperature inside the battery rises when charge completed and approaches an over charge region, and pressure inside the battery also begins to rise by hydrogen gas generated from a negative electrode 2. However, when the battery temperature reaches a set value, the detector 12 detects the battery temperature, and the automatic on-off switch 15 of a charge circuit 14 is operated by the control of a controller 16 so that no charge current flows any more.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminated sealed metal oxide-hydrogen storage battery and a group battery system using as a negative electrode a hydrogen storage electrode made of a hydrogen storage alloy or hydride that electrochemically stores and releases hydrogen. Regarding how to charge them.

[0002]

2. Description of the Related Art A hydrogen storage electrode using a hydrogen storage alloy or its hydride that reversibly stores and releases hydrogen is used as a negative electrode.
A laminated sealed nickel oxide-hydrogen storage battery using a metal oxide as a positive electrode usually generates a large amount of oxygen gas during charging, particularly when it enters an overcharge region. Then, in some cases, hydrogen gas is generated from the negative electrode. The generation of these gases causes the battery internal pressure to rise for each cell, and the reaction heat of this gas also causes the battery temperature to rise sharply, which poses a safety problem. Therefore, when the battery temperature rises and the internal pressure of the battery exceeds a predetermined pressure, the safety valve operates.

If the safety valve operates due to an abnormal increase in battery internal temperature or battery internal pressure after charging, leakage of the electrolytic solution from the safety valve or release of decomposed gas of the electrolytic solution occurs. In this case, the electrolytic solution in the battery decreases with charge / discharge cycles, and the capacity decreases. In order to prevent this capacity decrease, in a cylindrical Ni-Cd storage battery, the charging voltage rises during overcharge, and the following reaction occurs on the negative electrode side in the overcharge region,
Since oxygen generated in the positive electrode is absorbed in the negative electrode, the rise in battery internal pressure is suppressed to some extent. That is, when the battery is charged, first, the positive electrode having a small capacity is fully charged, and the electrolysis of water in the electrolytic solution causes a reaction of 4OH ⁻ → 2H ₂ O + O ₂ + 4e at the positive electrode to start generation of oxygen gas. Oxygen gas generated from the positive electrode diffuses through the separator to the negative electrode side and reacts with Cd as follows.

[0004] (Gas _{Consumption) Cd + 1 / 2O 2 +} H 2 O → Cd (OH) 2 addition, Cd (OH) ₂ produced in the _{charging, Cd (OH) 2 + 2e} - → CD + 2OH - reaction to metals Cd of Is played. When Cd reacts with oxygen gas, the temperature inside the battery rises and the battery voltage drops. As shown in Fig. 1, the peak of this voltage is
ΔV is set, and this −ΔV is detected to reduce the charging current to suppress the pressure increase in the battery due to overcharging. This is a normal charging method based on the so-called -ΔV method. On the other hand, a V-taper method is used as a kind of constant voltage charging in a mobile power source, especially in a lead storage battery for electric vehicles. This charging method charges at a constant voltage, and the charging current at this time may change depending on the battery at the time of charging, but in general, when the charging voltage reaches the set voltage, the charging current decays and the electrolyte due to overcharging The decomposition is reduced, the decrease in the amount of the electrolytic solution is suppressed as much as possible, the decrease in the charging efficiency due to the abnormal temperature rise is prevented, and the charging is completed. A so-called open-type lead-acid battery that uses a large amount of electrolyte has a relatively small temperature rise and is cheaper than other batteries, and is therefore often used as a power source for electric vehicles. Then, as described above, the control is performed only by detecting the charging voltage by the relatively simple quasi-constant voltage charging method.

[0005]

As a charging method adopted in a cylindrical Ni-Cd storage battery, as shown in FIG.
When the ΔV method is used, it is effective only when the electrolytic solution in the battery is regulated to some extent, and is not applied to a rectangular battery having a relatively large capacity.

A nickel-hydrogen storage battery (Ni / MH) can also be used in a cylindrical storage battery having a relatively small capacity, but a stationary storage battery having a relatively large amount of electrolyte and a large capacity,
In a closed prismatic Ni / MH storage battery as a power source for movement, such behavior of −ΔV is hard to appear, and it is difficult to control the charging current. An example of charge / discharge characteristics of this battery is shown in FIG.

The method for detecting the charging voltage alone changes the charging voltage even in the module battery, and also largely changes depending on the charging current and the temperature. Therefore, even if the charging voltage is set, it is optimal for extracting the maximum capacity. There is a problem that it is difficult to charge the battery properly. Therefore, in many cases, charging is repeated up to the overcharged state by the constant current charging method, but in this case, the amount of electrolytic solution is largely reduced and the capacity is largely reduced.

Therefore, the number of times of replacement fluid increases, which is a problem in handling. On the other hand, in the V taper method (a type of constant voltage charging) like a lead acid battery, a large charging current flows at the beginning because the set voltage at the time of charging is high, which reduces the activity of the electrodes and shortens the cycle life of the battery. have. If this charging method is used alone, the set voltage differs among the module batteries, and also changes depending on the charging current, temperature, etc., so it is difficult to perform optimal charging while suppressing the rise in pressure and temperature inside the batteries.

In general, a laminated sealed storage battery is a plurality of unit cells,
Alternatively, they are treated the same because they are composed of independent cells and are integrated. Therefore, even if 5 or 10 independent cells are stacked, they can be regarded as the same laminated sealed storage battery, but a charging method for reducing the temperature rise width of these unit cells (or cells). Is desired.

Therefore, the plurality of unit cells (or unit cells)
In a laminated sealed storage battery (module battery) composed of, since the unit cells are laminated and integrated, the amount of heat generated in each unit cell during charging is the same as the amount of heat released to the outside (in the atmosphere). In a unit cell with a relatively small heat dissipation area or a unit cell in which heat easily accumulates inside the battery, the internal temperature of the battery and the internal pressure of the battery increase significantly, resulting in poor charging efficiency and low discharge capacity. However, if charging and discharging are repeated, this tendency becomes large and the cycle life becomes short. If a plurality of modules are assembled and a group battery system having a high voltage is combined to obtain a required voltage from the module batteries, this tendency becomes more and more manifest as the number of each module battery increases. In this group battery system, even if one unit cell having poor battery characteristics is generated, the characteristics and safety of the group battery system are greatly affected. Since many unit cells are used in a stacked state, if there is a unit cell with an abnormally high temperature and pressure among them, hydrogen gas etc. will be generated from the inside of the cell, which poses a problem from the viewpoint of safety. Have

The present invention solves these drawbacks.
Metal oxide-hydrogen storage battery and group battery system with long charge / discharge cycle life, no need for maintenance such as replacement fluid, no significant increase in battery temperature and pressure, improved reliability and safety, and charging method thereof It is intended to provide.

[0012]

In order to solve this problem, the present invention provides a positive electrode mainly composed of a metal oxide, and a negative electrode mainly composed of a hydrogen storage alloy or a hydride thereof which electrochemically stores and releases hydrogen. And a laminated sealed metal oxide-hydrogen storage battery (hereinafter also referred to as “module battery”) that includes an alkaline electrolyte, is composed of a plurality of unit cells or unit cells, and has a safety valve on the lid portion of the exterior body. In order to control the battery temperature so that the internal pressure of the module battery does not exceed the operating pressure of the safety valve, the battery cell of the unit cell or unit cell at or near the center where the temperature of the module battery becomes the highest A temperature detector is arranged in at least one of the inside and a part of the outer surface of the battery case or the pole portion thereof, and the temperature detector alone or the charging voltage detector and / or the timer. In conjunction with open-closed or the charging circuit is characterized in that a control device for increasing & Gensa charging current.

The present invention also provides a group battery system in which a plurality of stacked hermetically sealed metal oxide-hydrogen storage batteries (module batteries) are connected in series so as to have a high voltage,
Of the module batteries that are close to each other in the group battery system, at least one of the module batteries has the highest temperature in the central portion or in the vicinity of the central portion. A temperature detector is arranged at at least one of the outer surface part or at least one of the poles, and the charging circuit is provided by the temperature detector alone or in conjunction with the charging voltage detector and / or the timer. It is characterized by having a control device for opening / closing or increasing / decreasing the charging current.

In the laminated hermetically sealed metal oxide-hydrogen storage battery or group battery system, the laminated hermetically sealed metal oxide-hydrogen storage battery (module battery) is mounted and fixed on a pedestal capable of supplying air to the bottom surface thereof, and is charged during charging. It is preferable that the bottom surface of the module battery can be naturally cooled or cooled by blowing air.

The laminated hermetically sealed metal oxide-hydrogen storage battery or group battery system is characterized in that copper is provided on both side surfaces of the laminated hermetically sealed metal oxide-hydrogen storage battery (module battery) in the stacking direction.
It is preferable that a reinforcing member made of a metal plate having good thermal conductivity such as aluminum or an alloy thereof is arranged, and the module battery is fastened and fixed via the reinforcing member.

In the laminated hermetically sealed metal oxide-hydrogen storage battery or group battery system, a separator is arranged between the positive electrode and the negative electrode, and a hydrophilic material is interposed between the positive electrode / negative electrode and the separator. It is preferable to configure.

In the laminated hermetically sealed metal oxide-hydrogen storage battery or group battery system, an electrode group in which a separator is interposed between a positive electrode and a negative electrode is arranged in a plurality of battery cells, and the electrolysis contained in the electrode group is arranged. In addition to the liquid amount, it is preferable that the electrolytic solution is stored in the inner bottom portions of the plurality of battery cases, and a part of the separator in the electrode group is immersed in the stored electrolytic solution.

Further, the present invention comprises a positive electrode mainly composed of a metal oxide, a negative electrode mainly composed of a hydrogen storage alloy or a hydride thereof which stores and releases hydrogen electrochemically, and an alkaline electrolyte. A group battery composed of unit cells or single cells, and a plurality of stacked hermetically sealed metal oxide-hydrogen storage batteries (module batteries) having a safety valve on the lid portion of the outer package, which are connected in series to have a high voltage In the system charging method, the temperature of a plurality of module batteries that are close to each other in the group battery system is detected so that a module battery in which the battery internal temperature and the battery internal pressure during charging are abnormally high does not occur. The temperature of the highest module battery among them is further detected by the temperature detector, and in conjunction with the temperature detector, the charging circuit opens when the highest temperature among them reaches the set temperature. Stops charging or reduces the charging current, and when the specified charge capacity is reached, stops charging by the timer to suppress the rise in battery internal pressure and battery internal temperature, temperature distribution and pressure in the group battery system. The feature is that the difference in distribution is reduced to enable charging with a uniform battery capacity.

Further, the present invention provides a method for charging a group battery system in which a plurality of stacked hermetically sealed metal oxide-hydrogen storage batteries (module batteries) are connected in series so as to have a high voltage. In order to prevent the occurrence of a module battery in which the temperature and the battery internal pressure become abnormally high, the temperature rise range from the start of charging of a plurality of module batteries that are close to each other in the group battery system is detected, and The temperature detector detects the temperature rise range of the battery with the largest temperature rise range, and the charging circuit is opened when the temperature rise range reaches the set temperature range at the earliest, in conjunction with the temperature detector. The charging is stopped or the charging current is reduced, and when the predetermined charging completion time is reached, the charging is stopped by the timer.

Further, the present invention provides a method of charging a group battery system in which a plurality of stacked hermetically sealed metal oxide-hydrogen storage batteries (module batteries) are connected in series so as to have a high voltage. In addition to the charging voltage, the entire group battery system is divided into several groups of small battery groups (several module batteries), and the charging voltage of each of the divided battery groups is detected independently, and it becomes the fastest during charging. The charging voltage of a specific battery group is detected by the charging voltage detector and the charging circuit is opened to stop charging, or the charging current is reduced and when a predetermined charging completion time is reached, the timer stops charging. And

Further, the present invention provides a method for charging a group battery system in which a plurality of stacked hermetically sealed metal oxide-hydrogen storage batteries (module batteries) are connected in series to provide a high voltage. Detects the temperature when the temperature rises fastest in the battery pack system that is installed, detects the time to reach the set temperature and the largest rise temperature range in the battery pack system, and sets the set temperature range. And the group battery system is divided into group batteries of several module batteries, the charging voltage of each group battery is detected independently, and the charging of the specific battery group that becomes the fastest during charging is charged. When the voltage is detected by the charging voltage detector and at least one of these detectors reaches the set value the earliest in the time it takes to reach the set voltage, the detector opens the charging circuit to charge it. The reduces or charging current is stopped, characterized in that to stop charging with the timer reaches the set time of the completion of charging.

Further, the present invention provides a method for charging a group battery system in which a plurality of stacked hermetically sealed metal oxide-hydrogen storage batteries (module batteries) are connected in series so as to have a high voltage, by natural cooling or air blowing. Charging and charging suspension are alternately performed by cooling, intermittent charging is performed to suppress abnormal rise in battery temperature and battery pressure, and when the charging completion time is reached, the timer completely stops charging. And

Further, the present invention provides a method for charging a group battery system in which a plurality of stacked hermetically sealed metal oxide-hydrogen storage batteries (module batteries) are connected in series so as to have a high voltage. It detects the battery temperature, the temperature rise range of the battery, the charging voltage of the battery group consisting of several divided module batteries, and opens the charging circuit with at least one detector that has reached each set value quickly to perform charging. The feature is that it is completely canceled.

Further, the present invention provides a method for charging a group battery system in which a plurality of stacked hermetically sealed metal oxide-hydrogen storage batteries (module batteries) are connected in series so as to have a high voltage, by natural cooling or air blowing. By cooling
The battery temperature in the group battery system, the temperature rise range of the battery,
The charging voltage of a battery group consisting of several divided modules is detected, and the charging circuit opens and the charging is completely stopped by at least one detector that quickly reached each set value. Characterize.

Further, the present invention is a method for intermittently charging a laminated sealed metal oxide-hydrogen storage battery (module battery) or a group battery system, in which the maximum value of the battery temperature raised by charging is set. When the set battery temperature is reached, the charging circuit is opened, charging is suspended, the minimum temperature drop is set by stopping charging, and when the set battery temperature drops, the charging circuit is restored and charging is restarted. Is performed at least once, and a timer is operated at a set time to complete charging, and charging is completely stopped.

It is preferable that the maximum value of the battery temperature increased by the charging is set to 30 to 45 ° C., and the minimum value of the lowered temperature due to the stop of charging is set to 20 to 35 ° C.

Further, in the charging method of the laminated sealed metal oxide-hydrogen storage battery or group battery system, the charging rate is 0.1 to 0.5 C at the charging current and the battery capacity is 125.
It is preferable to set the charging time with a timer so that the battery will not be charged more than 100%.

Further, in the above-mentioned laminated sealed metal oxide-hydrogen storage battery or group battery system or the charging method thereof, a module battery or a unit cell in a group battery system composed of a plurality of module batteries is an independent single cell. In addition, a space is formed between the unit cells in the stacking direction, and a plurality of the unit cells are combined in a stacked form to form an assembled battery (module battery). It is preferable that the fixing device is used for squeezing, and a temperature detector is mounted in the space and is connected to the charging circuit.

Further, in the above-mentioned laminated sealed metal oxide-hydrogen storage battery or group battery system and their charging method,
In a hermetically sealed metal oxide-hydrogen storage battery (module battery) or a group battery system composed of a plurality of modules,
When the charging operation is started again after the discharge of the battery is completed, the temperature of the module battery or the group battery system is 35 ° C. or more as the temperature detected by the detector, and the battery is not charged, the battery is not charged. It is preferable to have a charge control function capable of resuming charging after the temperature becomes approximately 30 ° C. or lower or in a state where the temperature is approximately 30 ° C. or lower so that charging cannot be performed at a high temperature.

In the group battery system or the charging method thereof, in the group battery system composed of a plurality of module batteries, when an overcurrent other than the charging current flows in the group battery system, or in the group battery system, When a leakage current occurs outside, it is preferable to detect the abnormal current or voltage and stop the charging operation.

[0031]

The present invention has the following functions due to the above construction.

In a battery with regulated positive electrode capacity, when overcharged, the electrolytic solution is decomposed by the following reactions (1), (2) and (3) to generate oxygen from the positive electrode, and hydrogen ions of hydride are generated in the negative electrode. Reacts to produce water.

Positive electrode: H ₂ O → 1 / 2O ₂ + H ⁺ + 2e (1) Negative electrode: M + 2H ⁺ + 2e ⁻ → M + 2 Had (hydrogen occluded) → MH ₂ (hydride) (2) MH ₂ +1 / 2O ₂ → M + H ₂ O (water) (3) If this reaction proceeds stoichiometrically, most of the oxygen generated during overcharge will be absorbed by the negative electrode, and the pressure increase in the battery can be suppressed. become. In this reaction process, if the overcharge region is entered, reactions (1), (2), (3)
The amount of heat generated is generated, and the temperature in the battery rises due to this reaction heat. However, if the heat radiation from the surface of the battery case is good, the temperature rise inside the battery will be small. On the contrary, if the heat radiation is poor and the amount of heat is accumulated in the battery, the temperature inside the battery will rise abnormally and the battery performance will be significantly lowered. Further, in the case of a battery system having a relatively large capacity and a relatively large amount of electrolyte, this stoichiometric reaction does not proceed, and the temperature rise in the battery is large due to the oxidation state of the negative electrode surface, catalytic action, etc. Will be different. Thus, it is difficult to keep the battery temperature constant.
In particular, in the case of a laminated sealed metal oxide-hydrogen storage battery (module battery), the temperature inside the battery (battery surface temperature) that rises during charging depends not only on the shape and material but also on the position of the unit battery or the arrangement of the module battery. different. Therefore, the charging circuit is cut by using a plurality of temperature detectors equipped in the battery to detect the highest battery temperature with the temperature detector so as not to generate abnormal unit cells or module batteries during overcharging. Alternatively, by reducing the charging current, it is possible to suppress the rise in the temperature inside the battery, reduce the temperature range of all the batteries as much as possible, and reduce the variation in the discharge capacity. When the temperature inside the battery rises in this way, hydrogen gas is released from the negative electrode and the pressure inside the battery also rises. This pressure rises to the physical property value of the equilibrium dissociation pressure of the hydrogen storage alloy forming the negative electrode. Therefore, a set temperature is provided, and the charging current is cut or the charging current is reduced by the temperature detector that reaches one of the set temperatures among the plurality of temperature detectors. The charging efficiency and safety can be improved and the service life can be extended by suppressing the increase of the battery.

Further, the set voltage and the set temperature are determined depending on the pressure resistance and heat resistance of the battery case, or the set voltage and the set temperature are provided in combination so that the oxygen gas can be absorbed by the negative electrode as efficiently as possible. In, the charge current is cut off when any of the divided group batteries reaches this value, or the charge current is reduced so that the battery pressure does not exceed the set pressure. This has the effect of preventing the battery capacity from decreasing due to the above and extending the service life.

[0035]

EXAMPLE A laminated hermetically sealed metal oxide according to an example of the present invention will be described below.
The hydrogen storage battery, the group battery system, and their charging method will be described in detail with reference to the drawings. (Example 1) First, a commercial product (purity 99.9% or more) was adopted as a metal constituting a hydrogen storage alloy, and an alloy composition Mm was used.
_{Ni 3.6 Mn 0.4 Al 0.3 Co 0.7} ( however, Mm is the a mixture of rare earth metals) to prepare a hydrogen-absorbing alloy of AB ₅ type structure in the high-frequency induction heating melting method. This alloy was mechanically finely pulverized by a pulverizer until the particle size (diameter) became 50 μm or less, to obtain a hydrogen storage alloy powder for the negative electrode. A water-repellent fluororesin such as poly-4, which is a binder made of an alkali-resistant organic synthetic resin, is added to the hydrogen storage alloy powder
A fluorinated ethylene resin (PTFE) was added together with a solvent to form a paste, which was applied to the surface of a porous body such as a punching metal (perforated plate) or an expanded metal, which is an electrode support, and then pressure-molded to obtain a negative electrode. .. As another example, a binder made of a polyvinyl alcohol (PVA) and carboxymethyl cellulose (CMC) solution as a hydrophilic resin is added to the above hydrogen storage alloy powder to form a paste, and a foamed nickel that is an electrode support is used. The porous body was pressure-filled to obtain a negative electrode. For the positive electrode, an electrode was used in which an active material mainly composed of nickel hydroxide was pressure-filled into a foamed nickel porous body.

A polyolefin separator, for example, a polypropylene separator or a polyamide separator, for example, a nylon separator, is arranged between both electrodes to form an electrode group, and this electrode group is arranged in a battery case. The basic configuration of this unit cell (unit cell) is shown in FIG.

As a basic structure of this battery, a separator 3 is interposed between a positive electrode 1 and a negative electrode 2 to form an electrode group 4, and the electrode group 4 is arranged in a battery case 5 to provide a safety valve (also serving as a liquid injection stopper). )
It is sealed with a lid 7 on which the electrodes 6 are attached.
The positive pole and negative pole poles 10 and 11 connected to 2 are fixed. The electrode group 4 in the battery case 5 of the unit cell contains the electrolytic solution, and further, the electrolytic solution 8 is held at the bottom of the battery case, and the amount of the electrolytic solution is set such that the end of the separator 3 is immersed in the electrolytic solution 8. .. In order to configure this unit cell with a 6V or 12V module battery as a unit module, 5 cells or 1 cell is used.
0 cells are laminated and integrated to assemble a laminated sealed battery.
An example of the 5-cell module battery is shown in FIG. Figure 4
In FIG. 3, an electrode group 4 composed of a positive electrode, a negative electrode and a separator as shown in FIG. 3 is arranged in a module battery case 9 composed of a plurality of unit cells. The unit cells are connected in series by the + pole column 10 and the − pole column 11. Moreover, the temperature detector 12 for detecting the temperature inside the battery is attached to the lid of the unit cell battery case at or near the center of the laminated hermetic storage battery. In this laminated sealed storage battery, a charging current flows from the positive electrode terminal 10 through the charging circuit 14 to the negative electrode terminal 11 by the charger 13. The charging circuit 14 is provided with an automatic opening / closing switch 15 and a controller 16 that detects the temperature inside the battery and operates in conjunction with the automatic opening / closing switch 15. A positive electrode and a negative electrode were selected to have an appropriate capacity ratio, and a plurality of electrodes were laminated to form a battery of about 100 Ah. The battery case is made of resin or metal, but in this embodiment, polypropylene resin is used and the operating pressure of the safety valve is set to about 1 to ² kg / cm ² . The module battery made of this resin is designated as A.

As charging / discharging conditions, first, charging depends on the battery capacity, but if the capacity is 100 Ah, it is charged at a current of 10 to 20 A (equivalent to 0.1 to 0.2 C), and at a current of 20 A. Final voltage of 5.0V for 5 cells
It was discharged to (average unit cell voltage 1.0 V). The ambient temperature was 25 ° C. The set temperature was set to 45 ° C. as the maximum temperature in the module battery. The charging curve during charging, the temperature rise of the battery, and the distribution of temperature, discharge capacity, etc. of each unit cell were measured. In addition, the charge / discharge cycle life was evaluated by the number of cycles when only one electrolyte solution was used. The decrease in capacity was defined as the life when the capacity deteriorated by 30% or more from the initial capacity. The electrolyte was mainly composed of a specific gravity 1.30 KOH solution.

As a charging method, a temperature detector was set to a predetermined temperature of 45 ° C., and a charging current was applied to the laminated sealed storage battery (module battery) by the charger 13. When charging is completed and the battery is near the overcharge area, the temperature inside the battery rises as shown in Fig. 2.
The hydrogen gas generated from the negative electrode also starts to increase the internal pressure of the battery, but when the battery temperature reaches 45 ° C., the temperature detector 12 detects the battery temperature, and the controller 16 controls the automatic open / close switch 15 of the charging circuit 14. I cut it so that the charging current would not flow. When the charging is completed, the load is taken from the discharging circuit and the discharging is completed. FIG. 5 shows the relationship between the charging voltage and the temperature inside the battery with respect to the charging rate during charging. As shown in FIG. 5, even if the battery voltage during charging does not reach the set voltage, for example, 1.50 V, the charging is stopped when the battery temperature reaches the set temperature of 45 ° C., and the increase in the battery temperature is suppressed. In particular, since the battery temperature rises significantly when entering the overcharge region, determining the optimum set temperature has a great influence on the cycle life characteristics. Therefore, it is important to determine the set temperature of the module battery, which is the highest of the stacked sealed storage batteries, from the viewpoint of the uniformity of the discharge capacity of the module battery and the cycle life. (Example 2) FIG. 6 shows the structure of a 12V module battery in which 10 cells of the unit cells shown in FIG. 3 are stacked. In the configuration of the module battery shown in FIG. 6, the bolts 21 and the nuts 2 are inserted from both sides in the stacking direction of the module battery through the reinforcing body 20.
A charging voltage for detecting the charging voltage of the temperature detector 17 or the module battery by arranging the temperature detector 17 on the outer surface of the battery case of the unit cell 18 located in the central portion of the module battery with a configuration tightened with 2 etc. The structure is the same as that of the first embodiment except that the control device 16 that opens and closes the charging circuit 14 in conjunction with the detector 19 is provided. This module battery is B
And

As a charging method, the temperature detector 17 is set to a predetermined temperature of 45 ° C., and the charging voltage is also linked to the charging voltage detector 19 in which the charging voltage is also set to a predetermined voltage. I did it. When the charging current is passed in this way, the temperature inside the battery rises due to the reaction heat of the battery, Joule heat inside the battery, etc., and hydrogen gas is generated from the negative electrode along with the temperature rise, and the battery pressure rises as the battery pressure rises. Internal temperature rises. Unit cell 1 located in the central portion of this module battery
When the battery case temperature of 8 reaches 45 ° C., the battery temperature is detected by the detector 17, and even if the other unit cells do not reach the temperature of 45 ° C., the automatic opening / closing switch 15 of the charging circuit 14 is controlled by the controller 1
I cut it with 6 so that the charging current would not flow. On the other hand, when the charging voltage reaches the set voltage, the charging voltage detector 19 detects the charging voltage, and the controller 16 cuts the automatic open / close switch 15 of the charging circuit 14 so that the charging current does not flow (Fig. 5). Either of the battery temperature and the charging voltage, the controller 16 cuts off the automatic open / close switch 15 of the charging circuit 14 when the set temperature and the set voltage are reached earlier so that the charging current is suppressed. (Embodiment 3) As shown in FIG. 7, in the structure of the module battery of FIG. 6, the temperature detector 23 is located in the central portion of the module battery, and the alloy negative electrode in which the temperature of the battery case of the unit cell 24 easily rises. The structure is the same as that of the second embodiment except that it is connected to the side pole 25. This module battery is designated as C.

The charging method is the same as that of the second embodiment except that the mounting position of the temperature detector of the second embodiment is different. (Example 4) 6V in which the unit cells of FIG.
16 module batteries are installed for this
Modules were connected in series and a group battery system 26 as shown in FIG. 8 was constructed to obtain a required high voltage. In the group battery system 26, the unit cells located at the central portions of the module batteries that are close to each other (in FIG. 6, symbol a,
b, c, d, e, f, g, h, i, j each 10 cells) 2
Each of the temperature detectors (sensors) 28 is mounted on the outer surface of the battery case 7 and the temperature detectors 2 are installed at 10 positions of the group battery system 26.
8 was attached. In the figure, the unit cells (symbols k and m) to which the temperature detector 28 is attached are comparative examples when they are attached to the outsides of the module batteries that are not close to each other. It is considered that the temperature rises during charging in the areas where the module batteries are close to each other.
This is a configuration including a controller 16 that opens and closes the automatic open / close switch 15 of the charging circuit in conjunction with 8 (10 places). Let this group battery system be D. As a charging method, the temperature detectors 28 (10 places) were set to a predetermined temperature of 45 ° C., and a charging current was supplied to the group battery system consisting of 16 modules by the charger 13. When charging is completed and the battery is near the overcharge region, the temperature of each battery rises, and the hydrogen gas generated from the negative electrode also starts to raise the internal pressure of each battery. In the group battery system 26 including a plurality of modules, the temperature of the unit cells indicated by the symbols a, b, c, d, e, f, g, h, i, j of the module batteries is detected by each temperature detector 28 (10 places). However, among the detected temperatures, at least 1 cell or more is the earliest
When the temperature reached the temperature, the battery temperature was detected and the automatic open / close switch 15 of the charging circuit was cut by the controller 16 so that the discharge current from the charger 13 did not flow. When the charging is completed, the load is taken from the discharging circuit and the discharging is completed. Otherwise, the method is the same as in Example 1. (Embodiment 5) 6V in which the unit cells of FIG.
A group battery system as shown in FIG. 9 was constructed in order to arrange a total of 16 module batteries for wiring and to connect all the modules in series to obtain a high voltage. Battery group A group 2 divided into 4 module batteries in this battery group system
9, the battery group B group 30, the battery group C group 31, and the battery group D group 32 are configured to detect the charging voltage. A charging current is supplied to each of the battery groups A, B, C, and D groups by the charger 13, and the charging voltage of each of the battery groups A, B, C, and D is linked with the charging voltage detector 19 to charge the charging circuit. This is a configuration including a controller 16 for opening and closing the automatic opening / closing switch 15. Let E be a group battery system including the divided battery groups.

As a charging method, the group battery system is divided into four groups of battery groups A, B, C and D for every four module batteries, and each charging voltage is set to a predetermined voltage.
In 3, the charging current was passed through the battery consisting of 16 modules.
When charging is completed and the battery is near the overcharge region, the charging voltage of the battery group increases, and the hydrogen gas generated from the negative electrode also starts increasing the internal pressure of the battery. At this time, the charging voltages of the batteries in each of the battery groups A, B, C, D consisting of four module batteries are detected, and when at least one or more of the battery group groups reaches the set voltage earliest, the charging is performed. The voltage is detected by the charging voltage detector 19, and the automatic open / close switch 15 of the charging circuit is cut by the controller 16 so that the charging current does not flow from the charger 13. When the charging is completed, the load is taken from the charging circuit and the discharging is completed. (Example 6) 6V in which the unit cells of FIG.
16 module batteries were connected in series and a group battery system was constructed to obtain a required high voltage. The temperature detection method during charging was the same as that of Example 4, and the charging voltage detection method was the same as that of Example 5, and were used together so that temperature detection and charging voltage detection could be performed simultaneously. This group battery system is designated as F.

As a charging method, the temperature detector was set to a predetermined temperature of 45 ° C., and the charging voltage was also set to a predetermined voltage at the same time.
When any one of the charging voltages of the group batteries A, B, C, and D divided into groups reaches the set temperature or the set charging voltage quickly, the automatic opening / closing switch of the charging circuit is cut by the controller, and the charger So that the charging current does not flow. (Embodiment 7) In Embodiments 1, 2, 3, 4, 5, 6, as shown in FIG. 10, the temperature detector 16 or the charging voltage detector 19 is interlocked with the automatic open / close switch 15 and the timer. The configuration is provided with the current attenuation control device 33 that reduces the charging current i from the charger 13. When the battery temperature or the charging battery voltage reaches the set temperature or the set voltage, the control device 33 that increases or decreases the charging current i functions to make the charging current 10
It was attenuated to A (0.1C) or less, and after a certain set time elapsed, the timer was operated, the charging current was completely cut off, and the charging current did not flow. Otherwise, Examples 1, 2,
It has the same configuration as 3, 4, 5, 6, and the charging method is also the same. The module battery of Example 1 was selected as an example of this module battery, and this module battery was designated as G. In addition, the group battery system of the fourth embodiment is selected as an example of the group battery system in which a plurality of module batteries are combined, and this group battery system is set to H. (Embodiment 8) 6V in which the unit cells of FIG.
The module battery m for use in the module battery m is configured, and the side surface in the stacking direction of the module battery m is tightened with the reinforcing body 20, and as shown in FIG. 11, cooling is possible from the battery bottom surface other than the top surface and the side surface of the module battery m. The structure is the same as that of the first and fourth embodiments except that the structure is fixed to the frame 36 provided with the cooling air supply window 34, and the charging method is also the same. Further, the reinforcing body 20 on the side surface of the battery from the stacking direction
Is a metallic material with excellent thermal conductivity, such as Cu, Al, F
e, Ni, Al alloy, brass, Fe Ni plated plate,
Alternatively, it is configured by a U-shaped angle or an L-shaped angle. This module battery is referred to as I, and a group battery system including a plurality of module batteries is referred to as J. 12A and 12B are a top view and a bb cross-sectional view of a pedestal 36 of the module battery when two module batteries are arranged. A highly insulating buffer member 37 is attached to the battery fixing portion, and a space portion 38 for air supply is provided at the bottom portion. (Example 9) 1 in which 10 unit cells of FIG.
A 2V module battery m is constructed, and the battery side surface in the stacking direction of the battery is made of a metal material having excellent thermal conductivity such as Cu, Al, Fe, Ni, Al alloy, brass, for example, a metal plate, a U-shape,
A structure in which a reinforcing body 20 such as an L-shaped plate is reinforced, and as shown in FIG. 13, the module battery m is fixed to a pedestal 36 provided with an air supply port 35 for air cooling so that the bottom surface of the module battery m can also be cooled and radiated. Except for the above, the configuration is the same as that of the second embodiment. The charging method is the same. This module battery is designated as K. (Example 10) A separator is placed between the positive electrode and the negative electrode, and a hydrophilic material such as polyethylene particles is interposed between the positive electrode and the negative electrode, and the positive electrode and the negative electrode are placed in a bag-shaped separator. The module battery was composed of the above electrode group, and the other structures were the same as those of the example 1. The charging method is the same. Let this module battery be L. (Embodiment 11) In the charging method according to Embodiment 4, the temperature detector for detecting the battery temperature is replaced with a rising temperature range from the start of charging, and the rising temperature range of the battery having the largest rising temperature range is detected. The width is further detected by the temperature detector, and in conjunction with the temperature detector, the charging current that flows from the charger by opening the charging circuit when the rising temperature width that rises fastest reaches the set temperature width of 15 to 20 ° C The charging is stopped or the charging current is reduced, and when the predetermined charging completion time is reached, the charging is stopped by the timer. Except for this charging method, the procedure is the same as in Example 4. Let M be a battery module system using this charging method. (Embodiment 12) In the charging method according to Embodiment 6, whether the highest battery temperature among the plurality of temperature detectors is detected,
Alternatively, a charging method that cuts charging or reduces charging current by detecting the highest charging voltage among the charging voltages of the batteries that divide the group battery system, and further detecting multiple rising temperature ranges from the start of charging In addition to the method of detecting the largest temperature range in the above, other than the charging method of cutting the charging or reducing the charging current when the set value is reached by at least one of these three types of detectors. Are all the same as in Example 6. Let this group battery system be N. (Embodiment 13) In the charging method of Embodiment 4, the charging and the charging pause are alternately performed by natural cooling or forced air cooling, and when the charging reaches the set time, the charging is completely stopped by the timer. At this time, charging current 10A
It was charged for about 2 hours, then rested for 2 hours, and charged for about 14 to 15 hours, which corresponds to about 125% charge. The group battery system charged by this charging method is set to O.

FIG. 14 shows the temperature rise of a specific module battery when the battery is charged with a charging current of 10 A, a charging time of 2 hours, and a rest time of 2 hours in an ambient temperature of 25 ° C. and forced air supply. With a battery capacity of 115 Ah, 125% charge corresponds to 14.3 hours, so the battery of this embodiment has 1
The temperature rises to about 38 ° C even after charging for 4.3 hours (equivalent to 125% charge), while it rises to 45 ° C when continuously charged. Heat generation during charging is alleviated due to charging suspension.
When the battery temperature rises, charging efficiency decreases, which is not preferable from the viewpoint of energy saving. The lower the battery temperature was, the larger the discharge capacity was, and the cooling and heat dissipation of the battery was also added, so that the battery temperature of the group battery system could be lowered to 7 ° C when the battery capacity was 125% charged. However, until charging is complete, 2
It takes 8.3 hours, and it is conceivable to increase the charging current in order to shorten the charging time. (Embodiment 14) In the intermittent charging method according to Embodiment 13, in the process of intermittently charging by alternating between charging and charging suspension, the battery temperature in the group battery system, the temperature rise width of the battery, the divided groups. Detects the charging voltage of each battery (4 module battery) and reaches each set value at least 1
With one detector, open the charging circuit and stop charging completely. Except for this charging method, the procedure is the same as in Example 13. The group battery system according to this charging method is P.
At this time, the set temperature is 45 ° C, the temperature rise width at the start of charging the battery is 20 ° C, the set charging voltage of the divided group batteries (4 modules) is 1.47V (25 ° C), the charging time is 2 hours, and the rest time is 2 hours. And (Fifteenth Embodiment) The charging method in the fourth embodiment is a charging method in which the charging and the charging pause are mutually intermittently performed by natural cooling or air blowing cooling. When charging, the battery temperature rises and this rises. Battery temperature up to 30
The temperature is set to ˜45 ° C., and when any of the temperature detectors reaches this set temperature, the charging circuit is opened and charging is temporarily stopped. Since the battery temperature drops when charging is stopped, the battery temperature that drops is set to at least 20 to 35 ° C. When the set temperature is reached, the charging circuit is restored and charging is restarted. This operation is alternately performed at least once. When the charging is completed, the timer cuts the charging at the set time. Except for this charging method, the same procedure as in Example 4 is performed.
Let this group battery system be Q. Charging was performed within the amplitude range of the maximum temperature of 40 ° C and the minimum temperature of 35 ° C and 5 ° C as set values. The charging time was 7 hours with 20 A charging, but it took 3 times or more even though the down time was air cooling.
As described above, in the present embodiment, the battery temperature decreased slowly during the rest, so that the rest time became longer. It is an effective means from the viewpoint of energy saving for applications that can be charged for a long time. (Embodiment 16) The module battery in Embodiments 1, 2, 3, 4, 5, 6 and the laminated sealed storage battery composed of a plurality of independent cells in the group battery system are used, and a space (air cooling) is provided between the cells. For example, a plurality of cells are stacked and combined, a temperature sensor is installed in the space of the central cell to form an aggregate battery, and reinforcements made of metal members from both end sides of the aggregate battery. The procedure is the same as in Examples 1, 2, 3, 4, 5, and 6 except that the body is squeezed and integrated. This charging method is also the same. As an example at this time, the module battery of Example 2 is selected and designated as R. The group battery system of the fourth embodiment including a plurality of module batteries is selected and designated as S. FIG. 15 shows a module battery of one example carried out here. The enlarged part of the temperature detecting portion is shown in FIGS.
A space 40 having a width of 2 to 5 mm is formed between the independent cells 39 constituting the module battery via a spacer 41 also serving as a reinforcement of the battery, and a temperature is provided on a side surface of the battery corresponding to a central portion of the module battery. A detector 42 is attached. The battery spacing 41 between the unit cells 39 also serves to reinforce the curvature of the unit cells 39, and is made vertical by the air flow as shown in FIG. 16 (a) or horizontal as shown in FIG. 16 (b). Can be placed. The width of the space 40 of the unit cell 39 can be adjusted by the height of the battery spacing body 41. It is also possible to form a group battery by combining a plurality of these module batteries.

Next, a comparative example will be described. (Comparative Example 1) This module battery is referred to as T, which is a module battery compared with Examples 1, 2, and 3. In this case, 125% charging is repeated without using the temperature detector. Alternatively, a case where the temperature detector is not arranged in the central portion of the module battery and the temperature detector is used in the battery case located at the outermost side of the battery is also added as a comparative example. (Comparative Example 2) This group battery system in which a plurality of module batteries are combined is referred to as a group battery system compared with Examples 4, 5, 6, and 7 and is referred to as U. In this case, only one type of detection method is used, and multiple detectors are not used.
This is the case when charging is repeated.

As a comparative example of Example 4, the detector is arranged in the outermost battery case of the group battery system. Since the temperature rise of the battery during charging is smaller than that of the module battery approaching the center, the temperature of the battery group system is controlled by the temperature of the battery, so the temperature of the battery group system rises relatively and the battery internal pressure increases. As a result, part of the electrolyte and gas (such as hydrogen gas) will be discharged from the safety valve.
Therefore, a battery with a reduced discharge capacity is generated, and the cycle life of the group battery system is shortened.

As a comparative example of the fifth embodiment, there is a configuration in which the charging voltage of the entire group battery system is detected. Since the charging voltage of the module batteries that make up the group battery system is not always the same, when controlling the charging by the entire charging voltage alone, a battery with a high charging voltage occurs and the temperature of the battery rises. At the same time, the battery becomes overcharged, the internal pressure of the battery rises, and the electrolyte and gas (hydrogen gas, etc.) are discharged from the safety valve. Therefore, a battery with a reduced discharge capacity is generated, and the cycle life of the group battery system is shortened.

The comparative example of Example 6 was the same as the case of only one of Examples 4 and 5. The total charging voltage and temperature were also detected at one location. Since the battery temperature is different for each module battery, if there is only one type of charge control means, a battery in an overcharged state will be generated depending on the set conditions, the internal pressure of the battery will rise, and electrolyte or gas (hydrogen gas, etc.) will be discharged. ,
A battery having a reduced discharge capacity is generated, and the cycle life of the group battery system is shortened.

The comparative example of Example 7 was the same as that of Comparative Example 2. In Comparative Example 2, only one type of detection method is used, and multiple detectors are not used. Therefore, charging is not cut, the charging current is reduced, and when the set charging time is reached, the timer stops the charging. However, due to the same phenomenon as in Comparative Example 2, the cycle life is shortened. (Comparative Example 3) A group battery system including a module battery and a plurality of module batteries is referred to as V, which is a module battery and a group battery system in comparison with Examples 8, 9, and 10. The comparative examples of Examples 8, 9 and 10 were the same as those of Comparative Examples 1 and 2.

When air cooling means and heat radiating means were added to Comparative Examples 1 and 2, there was an effect of controlling the temperature rise during charging, but basically the charging method was not improved and the temperature rise of the battery was made non-uniform. I can't avoid it. It becomes an effective method only when it is applied to the constitution of the laminated sealed storage battery (module battery) and the group battery system of the present invention and the charging method thereof. (Comparative Example 4) A group battery system including a plurality of module batteries is referred to as a group battery system in comparison with Example 11 as W.

As a comparative example of Example 11, a temperature detector for detecting the temperature rise width is arranged in the outermost battery case of the group battery system. When the detector for detecting the temperature rise range is being charged, if the battery rise temperature range is detected at a place where the battery rise temperature range is relatively small, there is a risk that the temperature rise range of the entire group battery system becomes too large. When the battery temperature rises unevenly, a cell with a high battery pressure is also generated, electrolyte and gas are discharged from the safety valve, and a battery with reduced discharge capacity is generated, which shortens the cycle life of the entire group battery system and is safe. There is also a problem in terms of sex. (Comparative Example 5) The group battery system compared with Example 12 is referred to as X.

As a comparative example of the twelfth embodiment, only one kind of charge control means is used, and the entire charge voltage is detected, or the battery temperature and the temperature rise range are detected only at one measurement point. This is the case when configured in. Since the temperature distribution of the group battery system is different during charging, it is not possible to completely reduce the battery temperature distribution with only a single detection method. Therefore, in each module battery, a battery whose temperature rises or becomes overcharged occurs, and the cycle life of the group battery system is shortened in the same manner. (Comparative Example 6) The group battery system in comparison with Examples 13, 14 and 15 is referred to as Y.

A comparative example of Examples 13, 14, and 15 is the case where the charging is intermittently operated in Comparative Examples 2 and 5. Although it is effective to provide air cooling / heat dissipation means to Comparative Examples 2 and 5 and to complete predetermined charging while alternately performing charging and rest, the charging control method is one type and the detection place is also as usual. Since it is performed at one place, it is unavoidable that the temperature rise of the battery is non-uniform. The charging start temperature and the charging resting temperature are not constant, and simple intermittent charging is not effective for the charging time. It becomes an effective method only when it is applied to the constitution of the laminated sealed type storage battery and the group battery system of the present invention and the charging method thereof. (Comparative Example 7) The module battery and group battery system in comparison with Example 16 will be referred to as Z. As a comparative example of this Example 16, the module battery and group battery system in Comparative Example 1 and Comparative Example 2 will be described. The same comparative example is used.

First, the purpose of the present invention for mounting the temperature detector on the central cell (or unit cell) of the module battery will be described.

The temperature of the battery case surface corresponding to the unit cell side surface of the module battery m shown in FIG. 17 was measured by each temperature detector 43 at 10 locations (symbols (1) to (10)) for each cell. FIG. 18 shows the temperature distribution when the battery is charged at 125% or more of the battery capacity at a charging current of about 10A. The number was entered on each cell from the + pole. It is a temperature distribution when the maximum temperature is 45 ° C. The temperature of the central portion corresponding to the unit cell numbers (5) and (6) indicates 45 ° C, whereas the unit cell numbers (1) and (10) on both ends of the cell are 38 ° C and 39.5 ° C. And about 5-7 ℃
You can see that it is low. Therefore, when the temperature of the unit cells on both ends of the module battery is detected, the temperature of the central unit cell is 5
The temperature rises above 0 ° C., and the internal pressure of the battery rises significantly. Also, the measured temperature differs depending on the mounting position of the temperature detector. The temperature inside the battery is about 5 ° C. higher than the side surface temperature of the battery case, and the temperature of the poles is in the middle. Therefore, it is necessary to adjust the set temperature according to the measurement position. Therefore, the temperature inside the battery can be detected as accurately as possible, and the rise in battery temperature can be suppressed to extend the cycle life. Therefore, it is important to detect the temperature by using the unit cell at the center of the module battery as a pilot battery. Next, this group of batteries is combined to form a group battery system. As shown in FIG. 18, the temperature distribution according to the temperature detection position at that time is shown in FIG. However, 12 at current 10A
This is the case when 5% charge and the set temperature is 45 ° C. From FIG. 18, the position of the temperature detector is indicated by symbol numbers (1) to (10). The symbol numbers (11) and (12) are added as comparative examples. It can be seen from the symbols (1) to (10) that the locations where the module batteries approach each other indicate a relatively high temperature. In addition to the position in the unit cell, the battery temperature varies depending on the location of the module battery itself. Therefore, in order to accurately detect the battery temperature, the place where the temperature detector is mounted is important.

The temperature detection place of the present invention is about 45 ± 1 ° C.
Although it is within the range, in order to further improve the accuracy of the set temperature, the symbols (3), (4), (6), (7), (9),
The position (10) is more preferable. Symbol of comparative example (1
1) and (12) are 40, 41 ℃ and about 5 ℃ low. Therefore, if the battery temperature is detected at the positions of the symbols (11) and (12), the temperature of the group system exceeds 50 ° C. and the cycle life is shortened. For this reason, it can be understood that it is appropriate to detect the temperature between the module batteries in which the module batteries are close to each other in the group battery system, and also by the central unit cell. Also, the charging current is 0.1
A charging rate equivalent to 0.5 C and a charging amount of about 125% of the battery capacity are optimal in terms of charging efficiency. This is because, as shown in FIG. 20, the relationship between the charging rate and the battery utilization rate is difficult even if the charging rate is 125% or more when the battery temperature is high. When the battery temperature is low, the battery utilization rate rises to about 95% as shown in FIG. Table 1 shows the cycle life test results of these various batteries which were tested by mounting the temperature detectors.

[0057]

[Table 1] From Table 1, the module battery and group battery system A, B, C, D, E, F, G, H, I, J according to the embodiment of the present invention,
The initial capacity of K, L, M, N, O, P, Q, R, S is 96.
~ 115Ah, 200th cycle in cycle life test,
The battery capacity at the 400th cycle is 95 to 114 Ah, 93
.About.112 Ah. Battery capacity reduction is about 1
%, About 3 to 4%, which is very small. This is because the amount of charge is limited by the temperature inside the battery during overcharging, it will not be overcharged more than necessary, and due to the rise in the temperature inside the battery, most of the oxygen gas generated from the positive electrode is efficiently absorbed by the negative electrode,
It is considered that the generation of hydrogen gas from the negative electrode is also small.
Therefore, there is almost no discharge of the electrolytic solution from the safety valve due to overcharge. Dispersion of discharge capacity (equivalent to 0.2C, 20
A discharge, 25 ° C.) was about 1 to 3 Ah for the module battery and about 2 to 4 Ah for the group battery system. The temperature distribution of the battery is set to the maximum temperature of 45 ° C, so 3 ~
It remains at a temperature difference of 6 ° C. Therefore, in the setting, the battery temperature does not rise to 45 ° C. or higher, but there is a delay in the transmission of the temperature inside the battery depending on the position of the temperature detector, and therefore the temperature tends to rise slightly thereafter. The cycle life test results in Table 1 are summarized in FIG. FIG. 21 compares the module battery and the group battery system of the present invention type and the conventional type. Among these, the module battery has less capacity reduction than the group battery system. It is considered that this is because the group battery system has a larger capacity variation due to the module battery, and the variation gradually spreads with the cycle life.

For the batteries A, B, and C, the measurement positions of the temperature detectors in the module batteries are different, and the detected temperatures are lowered by about 5 ° C. in the order of the temperature inside the battery, the poles, and the outer surface of the battery case. , It is necessary to adjust the set temperature according to the measurement position. A battery D, which constitutes a group battery system of an assembly by combining a plurality of module batteries of batteries A, B, and C, selects 10 modules in the central battery cell case where the module batteries approach each other, and attaches a temperature detector. However, in the case where the charging is completed when the set temperature reaches 45 ° C. earliest, there is no abnormal temperature rise in the module battery, which is effective for extending the cycle life. The battery temperature may be low depending on the ambient temperature, and it is possible that it will go deep into the overcharge region, so divide the charging voltage into four,
The battery E has a configuration in which the charging voltage of the divided battery group is detected and charging is cut off if there is a battery that reaches the set voltage earlier. When all the voltages of the group battery system are detected, even if an overcharged battery occurs in the module batteries, it cannot be identified.Therefore, the method of detecting the charging voltage of multiple modules at least by dividing it into groups It will increase the reliability of the system.

The battery F has both the batteries D and E, and one of the detectors operates in accordance with the ambient temperature to cut off the charge. In this way, since both the battery temperature and the charging voltage detector can suppress the battery temperature rise, it is considered that the charging method is also very useful for extending the cycle life.

For the batteries G and H, in the module battery and the group battery system, the method of completely cutting the charging circuit by the battery temperature and the battery voltage may be used, but the method of reducing the current is also effective and the utilization rate of the positive electrode is high. , Effective to prevent the memory effect from decreasing.

Batteries I, J and K are module batteries and group battery systems in the case where the cycle life and the discharge capacity are further extended, and not only the battery internal pressure but also the expansion of the electrode itself, etc. Since the bending and deformation of the electrolyte cause the electrolyte leakage phenomenon, the method of tightening with the reinforcing body from both side surfaces of the battery is an effective means. This reinforcing member is a heat conductive metal member (for example, Cu, Al, Fe, Ni, Al).
Alloy, brass, Fe-Ni plated plate or U-shape, L
The reinforcing member is also effective in releasing the heat generated during charging. Moreover, the module battery is mounted on a stand having an air supply window so that the heat can be dissipated from the bottom of the battery case. When the battery is charged, it is cooled from the surface of the battery by air to suppress an increase in the temperature inside the battery, and after the battery is charged to 125% or more, it is possible to suppress an increase in the battery temperature, which is very effective in extending the cycle life. Here, the battery is charged until the temperature rises to 45 ° C, and the charge amount is 12
It became possible to carry out 5% or more, and the discharge capacity increased. The battery capacity is 115A for the module battery.
h, a discharge capacity as large as 105 Ah could be obtained even in the group battery system. In addition, the rate of decrease in battery capacity over the cycle life is also decreasing. Dissipating heat from the bottom of the battery case is also an effective way to cool the battery. Since the air is supplied from the bottom surface to be cooled, the structure in which the air is forcibly supplied is more effective in extending the life of the battery. The battery capacity variation is small and the temperature rise rate is small. Even if the battery temperature is lowered, the pressure inside the battery rises when it enters the overcharge region, and the safety valve operating pressure is 1 to 2 kg / c.
When the pressure exceeds m ² , the electrolyte and gas are discharged from the safety valve, so it is necessary to set the temperature so as to adjust the pressure to less than this. The battery pressure in this case is about 1.3 kg.
/ cm ² . In the group battery system, the air cooling effect is not yet sufficient, and the discharge capacity is smaller than that of the module battery. However, when air cooling and heat radiation means are used, there is a difference in capacity of 10 to 15 Ah compared to the case where it is not. When heat is radiated well and forced air cooling is performed, the charge acceptance is obviously improved and the discharge capacity is improved.

With respect to the battery L, since the granular member holds the electrolytic solution in the separator, the amount of the electrolytic solution in the separator does not decrease, the capacity decreases little, and the discharge capacity increases a little.

The battery M has a structure in which the temperature rise width in the group battery system is detected from the temperature at the time of charging, and when the set temperature width is reached, the charging circuit is cut off or the charging current is reduced. 20 ° C is desirable. Ambient temperature 2
If charging is started at 5 ° C and the temperature rise width is set to 20 ° C, the battery temperature rarely exceeds 45 ° C. Therefore, the battery temperature can be suppressed within 45 ° C. and the charging efficiency can be improved.

When the temperature at the time of charging is low, for example, if the charging is started at 15 ° C., the charging is completed at 35 ° C.
If the battery is charged more than this, overcharging may be deeply promoted and the internal pressure of the battery may be increased.

For the battery N, in the group battery system, a structure for detecting the charging voltage of a battery group obtained by dividing the group battery system into a plurality of module batteries and a structure for detecting the battery temperature and the battery rise temperature range are used together. The charging circuit is cut off or the charging current is reduced when at least one kind of the detector reaches the set value quickly. By using this detector together, the rise in temperature inside the battery can be detected as accurately as possible depending on the ambient conditions, and the rise in pressure inside the battery during overcharging is suppressed, ensuring battery cycle life, safety, and reliability. Is effective to do.

The batteries O, P and Q are a method of charging in the group battery system by intermittently performing charging and charging pause in the air-cooled state.
A, charging time 2 hours, rest time 2 hours when charging Figure 1
As shown in 4, the rise in battery temperature is suppressed and the discharge capacity is improved.

The battery P has a set temperature of 45 ° C., the temperature rise width from the start of charging the battery is 20 ° C., and the set charging voltage of the divided group batteries (4 module batteries) is 7.35 V × 4 (29.
4V, 25 ° C.). When the charging time was 2 hours and the charging time was 2 hours, the discharge capacity was significantly improved. However, it is practically problematic because the time required for charging is significantly extended, but it is effective from the viewpoint of extending the cycle life of the battery. In this case as well, the cycle life is 4
A relatively high battery capacity is also shown at the 00th cycle.

In the group battery system, the battery Q is set to have a maximum battery temperature of 30 to 45 ° C. during charging and a minimum temperature of 20 to 35 ° C. at rest, and to be intermittently charged. The temperature rise does not rise above the set temperature, leading to a longer life, but the temperature during the rest time decreases for a long time, and even if air cooling is performed, the temperature once rises does not immediately fall and much time is required for the fall time. In short, this is an effective charging method for applications that can be charged for a long time, which is a little problematic in practical use.

As shown in FIGS. 15 and 16, the batteries R and S are a module battery and a group battery system. Independent battery cells are assembled and combined through a space for cooling. With the configuration tightened with
A space plate (reinforcement body) for preventing expansion of the battery case is installed in this space. The larger the width of this space portion is, the larger the entire volume is. Therefore, the width is preferably about 2 to 5 mm.
Moreover, the temperature detector is mounted on the surface of the battery case that forms the central space of the module battery. This space also works effectively for cooling the battery. Therefore, since the battery temperature does not rise significantly, the charging efficiency is good and the discharge capacity is large.
It has a long life. In this case, the battery temperature is 36 to 41 ° C., which is a relatively low value, even though the charging rate is 125%. Although the size of the group battery system is slightly increased, it exhibits excellent characteristics and is effective in improving reliability.
Further, there is an effect that a cell in which trouble occurs in the battery pack system can be easily replaced, which is also useful for cost reduction.

In the battery according to the embodiment of the present invention, the temperature of the battery may rise due to the failure of the temperature detector, but by using it together with other detectors, the abnormal temperature rise in the battery is prevented by the action of the safety valve. It also eliminates battery damage and enhances safety. Since the temperature inside the battery is detected, it is possible to prevent excessive overcharging even by charging. Therefore, rapid charging / discharging is also possible. Further, there is no need to maintain the electrolytic solution, and the handling becomes easy. Particularly, in the battery configuration, a battery capable of air cooling and heat dissipation is preferable. Furthermore, even higher performance batteries are possible by combining the cells. In short, it was possible to suppress the rise in battery temperature, improve safety, and extend the service life.

Comparative example battery T is a module battery,
This is the case when charging is repeated at 125% or more without using a temperature detector, or when the temperature is detected at a place other than the central portion. In this case, the battery temperature rises to 45 to 55 ° C., and the cycle life is greatly reduced. The average is 16% (13 to 19%) at the 200th cycle, and is 38% (32 to 48%) at the 400th cycle. A major cause of deterioration is the decrease in the amount of electrolyte due to the temperature rise in the battery.
Further, when the temperature becomes high, the charge acceptance is poor and the battery cannot be charged.
On the other hand, when the temperature rises, the hydrogen storage alloy that constitutes the negative electrode is oxidized, and this may cause a slight short circuit due to partial elution. This phenomenon is also considered to shorten the cycle life.

Comparative battery U is a battery pack system
The initial capacity is not so different, but the cycle life is short. Depending on whether a high battery temperature or an overcharged battery is generated in the cluster battery system, the internal pressure of the battery rises, and electrolyte or gas (hydrogen gas) is discharged, resulting in a battery with a reduced discharge capacity. Battery system cycle life is reduced.

Since the comparative battery V is a module battery and a battery group system which is provided with the air cooling and heat radiating means in the comparative examples 1 and 2, the initial capacity showed a slightly high value, but in the case of the comparative examples 1 and 2, Since the conditions are the same, the battery voltage cannot be detected and the battery temperature cannot be controlled, which causes a unit cell with a high battery temperature to occur, which is a cause of shortening the cycle life.

Comparative battery W is a battery pack system
When the temperature detector for detecting the temperature rise width is attached to the outermost battery cell of the group battery system, the maximum temperature of the group battery system becomes too high and the cycle life is shortened.

The comparative example battery X has a short life due to the same reason even in the group battery system. The comparative example battery Y has higher discharge capacity than the comparative examples 2 and 5 because it is provided with air cooling and heat radiating means in the group battery system, but it is still a unit cell (or unit cell) having a high battery temperature during charging. Occurs,
The cycle life of the battery pack system is shortened.

Comparative battery Z is a group battery system,
In the case where the batteries in Comparative Examples 1 and 2 are single batteries, the heat dissipation effect is provided, but the detection control of the battery temperature is incomplete, so that some batteries also increase in the battery internal temperature and the cycle life is shortened. Is causing The cause of the decrease in cycle life may include a minute short circuit phenomenon due to high temperature, and charging at high temperature is not preferable from the viewpoint of extending the cycle life.

In any case, the battery of the comparative example has an incomplete control of the battery temperature regardless of the presence or absence of air cooling and heat dissipation means, and the battery temperature is always abnormal during the cycle life test in the module battery or the group battery system. The rising battery has appeared, and this abnormal battery reduces the capacity of the entire group battery system. When the battery temperature becomes too high, disassembly takes precedence over charging and battery capacity decreases. This is why the decrease in battery capacity increases with cycle life. As the battery capacity decreases, the depth of overcharging further increases, which accelerates the decrease in discharge capacity. If the capacity further decreases, hydrogen gas is generated by entering the overdischarge region, which is not preferable from the viewpoint of safety. As described above, temperature control of each battery in the group battery system is important for extending the life.

The charging current is 0.1 to 0.5C,
Set the charging time with a timer so that the battery will not be charged more than 125% of its capacity. When the battery temperature is relatively low, the battery temperature may not reach 45 ° C, but even if the charge rate becomes 125% or more of the discharge capacity, the battery utilization efficiency does not improve, and 1
Charging 25% or more is not desirable from the viewpoint of energy saving.

Further, when an overcurrent flows during charging or when a current leaks inside and outside the group battery system, the current and voltage are detected and charging is stopped. Furthermore, when the charging is started again after the battery discharge is completed, the charging is not started when the temperature of the module battery and the group battery system is 35 ° C. or higher, and the charging is started when the battery temperature becomes 30 ° C. or lower, I made it possible to charge with good charging efficiency. To the end, it is effective in preventing charging at high temperatures and enhancing safety. It is also a desirable charging method from the viewpoint of extending the cycle life.

[0080]

As is apparent from the above description of the embodiments, according to the laminated sealed metal oxide-hydrogen storage battery (module battery) of the present invention, the group battery system including a plurality of modules, and their charging methods. Laminated sealed metal oxide-hydrogen storage battery (module battery) and multiple batteries with no abnormal battery temperature rise, long charge / discharge cycle life, quick charge / discharge, low maintenance, easy handling, and high safety The present invention provides a group battery system composed of the above module batteries and a charging method thereof.

[Brief description of drawings]

FIG. 1 is a characteristic diagram of a charging method using a −ΔV method.

FIG. 2 is a characteristic diagram showing charge / discharge characteristics of a battery.

FIG. 3 is a sectional view showing a basic configuration of a unit cell.

FIG. 4 is an explanatory diagram of a module battery connected to a charging circuit.

FIG. 5 is a characteristic diagram showing the relationship between the charging voltage and the battery temperature with respect to the charging rate.

FIG. 6 is an explanatory diagram of a module battery connected to a charging circuit.

FIG. 7 is an explanatory diagram of a module battery connected to a charging circuit.

FIG. 8 is an explanatory diagram of a group battery system connected to a charging circuit.

FIG. 9 is an explanatory diagram of a group battery system connected to a charging circuit.

FIG. 10 is a circuit diagram of a charging circuit (current decay)

FIG. 11 is a front view of a module battery fixed to a frame having an air supply window.

FIG. 12 (a) is a plan view of a pedestal of a module battery, and FIG. 12 (b) is a cross-sectional view taken along line bb thereof.

FIG. 13 is a front view of a module battery fixed to a frame having an air supply port.

FIG. 14 is a characteristic diagram showing a temperature rise change depending on charging conditions.

FIG. 15 is a front view of a module battery.

FIG. 16 is an enlarged view of the mounting portion of the temperature detector, and FIG.
6 (a) shows a vertical type, and FIG. 16 (b) shows a horizontal type.

FIG. 17 is a front view showing a temperature measurement state of a 10-cell laminated battery.

FIG. 18 is a characteristic diagram showing a temperature distribution of a laminated battery.

FIG. 19 is a characteristic diagram showing a temperature distribution of the battery pack system.

FIG. 20 is a characteristic diagram showing the relationship between the charging rate and the battery utilization rate.

FIG. 21 is a characteristic diagram showing cycle life of a metal oxide-hydrogen storage battery.

[Explanation of symbols]

 1 Positive Electrode 2 Negative Electrode 3 Separator 4 Electrode Group 5 Battery Case 6 Safety Valve (Liquid Stopper) 7 Lid 8 Electrolyte 9 Battery Case 10 Electrode Terminal (Polar Pole) 11 Electrode Terminal (Polar Pole) 12 Temperature Detector 13 Charger 14 Charging Circuit 15 Automatic opening / closing switch 16 Controller 17 Temperature detector 18 Unit cell at the center 19 Charging voltage detector 20 Reinforcement body 21 Bolt 22 Nut 23 Temperature detector 24 Unit cell at the center 25 Pole 26 Module battery group 27 Center Unit battery 28 Temperature detector 29 A battery group 30 B battery group 31 C battery group 32 D battery group 33 Current attenuation control device 34 Air supply window 35 Air supply port 36 Battery mount 37 Buffer member 38 Space portion 39 Single battery 40 Space Part 41 Battery interval body (reinforcement body) 42 Temperature detector 43 Temperature detector m Module battery

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Isao Matsumoto 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (19)

[Claims] 1. A plurality of unit cells or a unit cell comprising a positive electrode mainly composed of a metal oxide, a negative electrode mainly composed of a hydrogen storage alloy or its hydride that electrochemically stores and releases hydrogen, and an alkaline electrolyte. In a laminated sealed metal oxide-hydrogen storage battery (hereinafter also referred to as "module battery") that is composed of a battery and is provided with a safety valve on the lid portion of the exterior body, the internal pressure of the module battery is the operating pressure of the safety valve. In order to control the battery temperature so as not to exceed the temperature of the module battery, the temperature of the module battery becomes the highest, the inside of the battery case of the unit cell or the single battery at or near the center, and a part of the outer surface of this battery or its A temperature detector is arranged at at least one of the pole columns, and the charging circuit is opened by the temperature detector alone or in conjunction with the charging voltage detector and / or the timer.
A laminated sealed metal oxide-hydrogen storage battery comprising a control device for closing or increasing / decreasing a charging current. 2. A group battery system in which a plurality of stacked hermetically sealed metal oxide-hydrogen storage batteries (module batteries) are connected in series so as to have a high voltage, and are close to each other in the group battery system. Of the module batteries,
At least one of at least one of the inside of the battery case of the unit cell or the single battery at which the temperature of at least one module battery becomes the highest or the vicinity of the center and the inside of the battery case or a part of the outer surface of the battery case or the pole part thereof. A temperature detector is arranged in the temperature sensor, and a controller for opening / closing the charging circuit or increasing / decreasing the charging current by the temperature detector alone or in conjunction with the charging voltage detector and / or the timer is provided. Characteristic group battery system. 3. A laminated sealed metal oxide-hydrogen storage battery (module battery) is mounted and fixed on a pedestal capable of supplying air to the bottom surface thereof, and is naturally cooled or blown with air from the bottom surface of the module battery during charging. Claim 1 having a configuration capable of
Or the laminated hermetically sealed metal oxide-hydrogen storage battery or group battery system according to 2. 4. A reinforcing body made of a metal plate having good thermal conductivity, such as copper, aluminum, or an alloy thereof, is arranged on both side surfaces of the laminated hermetically sealed metal oxide-hydrogen storage battery (module battery) in the stacking direction, The laminated sealed metal oxide-hydrogen storage battery or group battery system according to any one of claims 1 to 3, wherein the module battery is clamped and fixed via the reinforcing body. 5. The laminated hermetically sealed structure according to claim 1, wherein a separator is arranged between the positive electrode and the negative electrode, and the electrode group has a hydrophilic material interposed between the positive electrode and the negative electrode. Type metal oxide-hydrogen storage battery or group battery system. 6. An electrode group in which a separator is interposed between a positive electrode and a negative electrode is arranged in a plurality of battery cases, and in addition to the amount of the electrolyte solution contained in the electrode group, an electrolyte solution is provided at the bottom of the plurality of battery cases. Is stored, and a part of the separator in the electrode group is soaked in this storage electrolyte solution. The laminated sealed metal oxide-hydrogen storage battery or group battery system according to claim 1. 7. A plurality of unit cells or a unit cell comprising a positive electrode mainly composed of a metal oxide, a negative electrode mainly composed of a hydrogen storage alloy or a hydride thereof which stores and releases hydrogen electrochemically, and an alkaline electrolyte. A method of charging a group battery system in which a plurality of stacked hermetically sealed metal oxide-hydrogen storage batteries (module batteries) each composed of a battery and provided with a safety valve on a lid portion of an exterior body are connected in series to have a high voltage In order to prevent the occurrence of a module battery in which the battery internal temperature and the battery internal pressure during charging become abnormally high, the temperatures of a plurality of module batteries that are close to each other in the group battery system are detected and In addition, the temperature of the highest module battery is detected by the temperature detector, and in conjunction with the temperature detector, when the highest temperature reaches the set temperature, the charging circuit is opened and charging is stopped. Or reduce the charging current,
When the predetermined charge capacity is reached, charging is stopped with a timer to suppress the rise in battery internal pressure and battery internal temperature,
A charging method for a group battery system, characterized in that a difference in temperature distribution and pressure distribution in the group battery system is reduced to enable charging with a uniform battery capacity. 8. A charging method for a group battery system, wherein a plurality of stacked hermetically sealed metal oxide-hydrogen storage batteries (module batteries) are connected in series so as to have a high voltage,
To prevent the occurrence of module batteries in which the battery internal temperature and battery pressure during charging become abnormally high, the temperature rise range from the start of charging of multiple module batteries that are close to each other in the group battery system is set. Detected, the temperature rising range of the battery with the largest temperature rising range is further detected by the temperature detector, and in conjunction with the temperature detector, the rising temperature range becomes the earliest and reaches the set temperature range. Then, the charging circuit is opened to stop the charging or reduce the charging current, and when a predetermined charging completion time is reached, the charging is stopped by a timer. 9. A charging method for a group battery system, wherein a plurality of stacked hermetically sealed metal oxide-hydrogen storage batteries (module batteries) are connected in series so as to have a high voltage.
In addition to the total charging voltage of the group battery system, the entire group battery system is a small group of several groups (several module batteries)
The charging voltage of the divided battery group is detected independently, and the charging voltage detector detects the charging voltage of the specific battery group that becomes the fastest during charging and opens the charging circuit to charge. Or a charging current is reduced to reach a predetermined charging completion time, and the charging is stopped by a timer. 10. A charging method for a group battery system, wherein a plurality of stacked hermetically sealed metal oxide-hydrogen storage batteries (module batteries) are connected in series to obtain a high voltage, and a plurality of temperature detectors are mounted. It detects the temperature when the temperature rises fastest in a certain group battery system, detects the time until it reaches the set temperature and the largest rise temperature range in the group battery system, and reaches the set temperature range. The time and the group battery system are divided into group batteries of several module batteries, and the charging voltage of each group battery is detected independently, and the charging voltage of the specific battery group that becomes the fastest during charging is the charging voltage. When at least one of these detectors reaches the set value at the earliest in the time it takes for the detector to reach the set voltage, the detector opens the charging circuit and stops charging. Or reduce the charging current,
A method of charging a battery group system, wherein charging is stopped by a timer when the set time for completion of charging is reached. 11. A charging method for a group battery system, wherein a plurality of stacked hermetically sealed metal oxide-hydrogen storage batteries (module batteries) are connected in series so as to have a high voltage, and are charged by natural cooling or air blowing cooling. A group battery characterized by alternating charging pauses and intermittent charging to suppress abnormal increases in battery temperature and battery pressure, and to completely stop charging with a timer when the charging completion time is reached. How to charge the system. 12. A charging method for a group battery system comprising a plurality of stacked hermetically sealed metal oxide-hydrogen storage batteries (module batteries) connected in series so as to have a high voltage. Temperature rise range of
The charging voltage of a battery group consisting of several divided modules is detected, and at least one detector that has reached each set value quickly opens the charging circuit to completely stop charging. A method of charging a battery pack system that features. 13. A charging method for a group battery system, wherein a plurality of stacked hermetically sealed metal oxide-hydrogen storage batteries (module batteries) are connected in series so as to have a high voltage, and are charged by natural cooling or air blowing cooling. The battery temperature in the group battery system, the temperature rise range of the battery, and the charging voltage of the battery group consisting of several divided module batteries are detected during charging. A method of charging a battery group system, wherein a charging circuit is opened to completely stop charging with at least one detector that has reached a set value quickly. 14. A method for intermittently charging a stacked sealed metal oxide-hydrogen storage battery (module battery) or a group battery system, wherein a maximum value of the battery temperature that rises due to charging is set, and this set battery temperature is set. When it reaches, open the charging circuit,
Charging is temporarily stopped, the minimum value of the temperature drop due to the stop of charging is set, and when the battery temperature drops to this set battery temperature, the charging circuit is restored and charging is restarted alternately at least once to complete the charging. A charging method for a laminated sealed metal oxide-hydrogen storage battery or a group battery system, wherein a timer is operated at a set time to completely stop charging. 15. The battery according to claim 14, wherein the maximum value of the battery temperature increased by the charging is set to 30 to 45 ° C., and the minimum value of the decreased temperature due to the stop of the charging is set to 20 to 35 ° C. 2. A method for charging a laminated hermetically sealed metal oxide-hydrogen storage battery or group battery system according to claim 1. 16. A charging rate of 0.1 to 0.
The stacked sealed metal oxide-hydrogen storage battery or group battery according to any one of claims 1 to 11 and 14 to 15, wherein the charging time is set by a timer so as not to charge 125% or more of the battery capacity at 5C. How to charge the system. 17. A module battery or a module battery in a group battery system composed of a plurality of module batteries is an independent single cell, and a space is formed between the single cells in the stacking direction to form a plurality of single cells. A combined battery (module battery) is formed by combining the batteries in a stacked form, and the structure is squeezed from both end side surfaces of the assembled battery with metal fixing and fixing tools, and a temperature detector is attached to the space portion, 16. The laminated sealed metal oxide-hydrogen storage battery or group battery system according to any one of claims 1 to 8 and 10 and 12 to 15, or a charging method thereof, which is connected to a charging circuit. 18. A stacked cell type metal oxide-hydrogen storage battery (module battery) or a group battery system comprising a plurality of modules, wherein when the charging operation is started again after the discharge of the battery is completed, the module battery or group battery system. When there is a battery with a temperature of 35 ° C or higher as the temperature detected by the detector, charging does not start, and charging can be resumed after the battery temperature drops below approximately 30 ° C or below approximately 30 ° C. 16. The laminated hermetically sealed metal oxide-hydrogen according to any one of claims 1 to 8 and 10 and 12 to 15, which has a charge control function and cannot be charged at a high temperature. Storage battery or group battery system and their charging method. 19. In a group battery system composed of a plurality of module batteries, when an overcurrent other than a charging current flows in the group battery system, or when a leakage current occurs inside / outside the group battery system, an abnormality thereof occurs. The group battery system or the charging method thereof according to any one of claims 2 to 18, which is configured to detect a current or a voltage and stop the charging operation.