JP2000348781A - Nonaqueous electrolyte battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a battery capable of preventing danger due to heat generation of a terminal even if an external short circuit or the like occurs by circulating a liquid coolant such as water or oil to positive and negative electrode terminals projecting from a battery case and thereby cooling the terminals. SOLUTION: Each cell 1 is provided with two positive electrode cell terminals 2 projecting from the front side end face of a battery case 8 and similarly provided with negative electrodes projected from the opposite side end face. The positive electrode cell terminals 2 are connected to a long Al set battery terminal 4 through an L-shaped Al connection fitting 3, the positive electrode side cell terminals 2 are connected to a long Cu set battery terminal 4 through a L-shaped Cu connection fitting 3, and their upper end faces are connected to an external apparatus. Water-cooled jackets 5 are provided on both side faces of this battery, the cells 1 are cooled by feeding cold water from a water- cooling circulation device 6 to a pipe 5a. The terminal parts are cooled as well by installing terminal water-cooling jackets 7 covering the cell terminals 2 and the set battery terminals 4. Thereby, even if a large current flows due to a short circuit or the like, heat is rapidly radiated so that the temperature rise of the battery can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a non-aqueous electrolyte battery such as a large-sized and large-capacity lithium ion secondary battery.

[0002]

2. Description of the Related Art A configuration example of a large-sized large-capacity lithium ion secondary battery will be described. If a large-sized, large-capacity lithium-ion secondary battery is composed of a single cell 1, manufacturing and maintenance are troublesome. Therefore, usually, a large-capacity lithium-ion secondary battery is usually composed of a plurality of unit cells 1 connected in parallel. As shown in FIG. 2, the unit cell 1 of such a lithium ion secondary battery is configured by housing a power generation element (not shown) in a rectangular battery case 8. In this configuration example, a stack-type power generating element in which a large number of positive and negative electrodes are stacked via a separator is used, and two such power generating elements are housed in the battery case 8 in a vertically stacked manner. In addition, since each of the power generating elements has the positive and negative unit cell terminals 2 protruding from both front and rear ends thereof, the two positive and negative unit cell terminals 2 are sealed up and down from the front and rear end surfaces of the battery case 8 respectively. It is designed to protrude. In addition, the lithium ion secondary battery of this configuration example is a single cell 1
However, since it reaches a weight of several tens of kg to about 100 kg, hooks 9 are provided on both sides of the cell terminals 2 at the front and rear end faces of the battery case 8, respectively, and the hooks 9 are transported by a crane or the like. ing.

A single cell 1 of the above lithium ion secondary battery
As shown in FIG. 3, a plurality of (10 in the figure) are vertically stacked and used as an assembled battery. At this time, each cell 1
L-shaped connection fittings 3 are respectively connected and fixed to the positive and negative electrode cell terminals 2 protruding from the front and rear end surfaces of the battery cell terminals. Each of the connection fittings 3 is a long plate-shaped positive and negative battery pack terminal. 4
Connected and fixed. In addition, battery water cooling jackets 5 are attached to both sides of the lithium ion secondary battery that has been assembled as described above, and water is circulated through pipes 5a arranged in these battery water cooling jackets 5,
Each unit cell 1 is cooled.

[0004]

Since large-sized and large-capacity secondary batteries are often used after being installed for a long period of time, correct rechargeable batteries due to water leaks from the installation facility or seawater intrusion when used on ships. It is necessary to consider the possibility that the battery terminals 4 of the negative electrode are short-circuited to each other to cause an external short circuit. However, for example, in the case of a lead-acid battery that has been conventionally used in large-sized and large-capacity secondary batteries, even if such an external short circuit occurs, the electrolyte solution, which is an aqueous solution of sulfuric acid, boils and evaporates, and There is no danger because the power generation is stopped by being released to the air.

However, in the case of a lithium ion secondary battery, since the non-aqueous electrolyte having a relatively high boiling point is hermetically sealed in the battery case 8, the temperature of the cell 1 becomes extremely high. Since the inside of the chamber 8 also has a high pressure, there is a danger of rupture or the like. However, in a lithium ion secondary battery,
In order to avoid such a danger, in addition to providing the above-mentioned battery water cooling jacket 5 to cool each of the cells 1, when the separator becomes high temperature, a shutdown occurs and the non-aqueous electrolyte is interrupted to stop power generation, A measure is taken to provide a safety valve in the battery case 8 to prevent rupture due to internal pressure.

However, since the lithium ion secondary battery uses the aluminum cell terminal 2 and the battery terminal 4 for the positive electrode, the lithium ion secondary battery has a higher electric resistance than the copper cell terminal 2 and the battery terminal 4 for the negative electrode. Become. For this reason, when a very large current flows as in the case of an external short circuit, heat generation at the positive electrode unit cell terminal 2 and the assembled battery terminal 4 becomes particularly large,
The temperature inside the cell 1 near the cell terminal 2 becomes extremely high.
In addition, when such a local abnormal high temperature occurs, the separator also melts and does not perform the shutdown function. For this reason, in the conventional particularly large-sized lithium ion secondary battery, there is a problem that the measures for heat generation of the unit cell terminal 2 and the assembled battery terminal 4 are not sufficient.

[0007] The above problem is the same in the case of the unit cell terminal 2 and the assembled battery terminal 4 of the negative electrode made of copper. Similar problems may occur with non-aqueous electrolyte batteries.

The present invention has been made in order to cope with such a situation. By cooling the terminals of the positive and negative electrodes with water, oil, or the like, even if an external short circuit or the like occurs, the danger due to the heat generation of the terminals can be reduced. It is an object of the present invention to provide a non-aqueous electrolyte battery which can be prevented.

[0009]

The non-aqueous electrolyte battery according to the present invention is characterized in that a cooling device for cooling the terminals by circulating a liquid refrigerant is attached to the positive and negative terminals protruding from the battery case. And

According to the first aspect of the present invention, since the terminals are cooled by circulating the liquid refrigerant, even if a large current flows through the terminals due to an external short circuit or the like, the heat generation at the terminals is quickly caused. Since the discharge and the rise in temperature inside the battery can be suppressed, danger due to heat generation of the nonaqueous electrolyte battery can be prevented.

According to a second aspect of the present invention, in the non-aqueous electrolyte battery, the cooling device has a jacket surrounding the terminals mounted on the exterior of the battery case, and a refrigerant circulation device for circulating a liquid refrigerant in the jacket. It is characterized by the following.

According to the second aspect of the present invention, since the liquid refrigerant circulates in the jacket surrounding the terminals, the terminals can be directly and effectively cooled.

According to a third aspect of the present invention, there is provided the non-aqueous electrolyte battery, wherein the cooling device forms a flow path of a liquid refrigerant in the terminal and a refrigerant circulation device for circulating the refrigerant in the flow path in the terminal. It is characterized by being.

According to the third aspect of the present invention, since the liquid refrigerant circulates in the flow path formed inside the terminal, the terminal can be efficiently cooled directly from the inside.

[0015]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an embodiment of the present invention, and FIG. 1 is a perspective view showing the structure of a large-sized and large-capacity lithium-ion secondary battery pack. Components having the same functions as those of the conventional example shown in FIGS. 2 and 3 are denoted by the same reference numerals.

The lithium ion secondary battery of the present embodiment is
A case where ten unit cells 1 having the same configuration as that shown in FIG. 2 are vertically stacked to form an assembled battery will be described. Each cell 1
In the battery case 8, two positive cell terminals 2 protrude from the front end face of the battery case 8, and two negative cell terminals 2 protrude from the other end face of the battery case 8. The single cell terminal 2 of the positive electrode is an aluminum male screw, and an L-shaped aluminum connection fitting 3 is attached to each of the two single cell terminals 2 of each single cell 1 and connected and fixed with a nut. . The cell terminal 2 of the negative electrode is a male screw made of copper and is hidden on the back surface in the figure.
An L-shaped copper connection fitting 3 is attached to each of the unit cell terminals 2 and connected and fixed with a nut. Further, each connection fitting 3 on the positive electrode side is fixedly connected to one long plate-shaped aluminum battery terminal 4 by caulking or the like,
Each connection fitting 3 on the negative electrode side is connected and fixed to one long plate-shaped copper battery terminal 4 by caulking or the like. These assembled battery terminals 4 are respectively drawn out to the upper end surfaces of the lithium ion secondary batteries which are assembled batteries, and are connected to external devices here.

Battery water cooling jackets 5 are attached to both sides of the lithium ion secondary battery as the assembled battery. Then, the cold water supplied from the water cooling circulating device 6 is supplied to the pipes 5 a arranged in these battery water cooling jackets 5.
By circulating the cells, the individual cells 1 are cooled. The water cooling circulation device 6 is a device for cooling and discharging the water discharged through the pipe 5a of the battery water cooling jacket 5 again.

On the front and rear surfaces of the lithium ion secondary battery as the assembled battery, terminal water cooling jackets 7 covering the unit cell terminal 2 and the connection fitting 3 and the assembled battery terminal 4 of each unit cell 1 are respectively attached. I have. The terminal water-cooling jacket 7 also covers the battery pack terminal 4 on the upper end surface, but exposes a connection portion with an external device. These terminal water cooling jackets 7 are provided with pipes inside similarly to the battery water cooling jacket 5, and circulate cold water supplied from the water cooling circulating device 6 also into the pipes. The terminal water cooling jacket 7 covers the cell terminals 2, the connection fittings 3, and the assembled battery terminals 4, and also seals the end faces of the cells 1, thereby allowing water to flow directly into the terminal water cooling jacket 7. You can also do so. In this case, for example, as shown by an arrow in FIG. 1, the cold water of the water-cooled circulation device 6 may be supplied to the inside of the terminal water-cooled jacket 7 from above and discharged from below. Further, instead of such a terminal water cooling jacket 7, for example, a flow path may be formed inside the battery pack terminal 4 and cold water may be supplied into this flow path. Further, a flow path may be formed inside the cell terminal 2 of each cell 1 and cold water may be supplied into the flow path.

According to the lithium ion secondary battery having the above-described structure, the cell terminals 2 and the assembled battery terminals 4 are cooled by the circulation of water. The heat generated in the battery terminals 2 and the assembled battery terminals 4 is quickly released, and the temperature rise inside the unit cell 1 can be suppressed. In particular, it is possible to prevent an abnormally high temperature in the vicinity of the unit cell terminal 2 and the assembled battery terminal 4 on the positive electrode side, which tends to generate a large amount of heat due to aluminum having higher electric resistance than copper, so A safe lithium ion secondary battery even with a large capacity can be provided.

In the above embodiment, the case where the water-cooled circulation device 6 using water cooling is used has been described. However, other liquid refrigerants such as oil and organic solvents can be used. In particular, it is preferable to use an electric insulating oil which is less likely to corrode and has excellent insulation properties for the refrigerant which is cooled by directly contacting the cell terminals 2 and the battery terminals 4. As the electric insulating oil, mineral oil, alkylbenzene, polybutene, alkylnaphthalene, alkyldiphenylethane, silicone oil or the like is used.

Further, in the above embodiment, the case where the unit cell terminal 2 has a male screw shape has been described, but the structure of the unit cell terminal 2 is arbitrary. Further, the structure of the assembled battery terminal 4 is also arbitrary, and it is possible to avoid using the connection fitting 3 or to integrate the assembled battery terminal 4 with the unit cell terminal 2.

Further, in the above embodiment, the lithium ion secondary battery used as the assembled battery has been described, but only the single battery 1 may be used. In the above embodiment,
Although the lithium ion secondary battery has been described, the present invention can be similarly applied to other batteries using a non-aqueous electrolyte.

[0024]

As is apparent from the above description, according to the nonaqueous electrolyte battery of the present invention, since the terminals are cooled by water, oil or the like, a large current flows through the terminals due to an external short circuit or the like. Also, danger due to heat generation at this terminal can be prevented.

[Brief description of the drawings]

FIG. 1, showing one embodiment of the present invention, is a perspective view illustrating a configuration of an assembled battery of a large-sized and large-capacity lithium-ion secondary battery.

FIG. 2 is a perspective view showing a configuration of a large-sized large-capacity lithium ion secondary battery unit cell used as an assembled battery.

FIG. 3 is a perspective view showing a conventional example and showing a configuration of an assembled battery of a large-sized large-capacity lithium ion secondary battery.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Single battery 2 Single battery terminal 3 Connection metal fitting 4 Assembled battery terminal 6 Water cooling circulation device 7 Terminal water cooling jacket 8 Battery case

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5E322 AA07 AA11 AB11 DA01 DA03 FA01 5H022 AA09 BB06 CC01 EE04 5H029 AJ12 BJ06 BJ22 CJ02 DJ02 DJ05 EJ03 EJ11 5H031 AA09 CC05 HH06 KK06

Claims (3)

[Claims] 1. A non-aqueous electrolyte battery characterized in that a cooling device for cooling a terminal by circulating a liquid refrigerant is attached to positive and negative terminals protruding from a battery case. 2. The cooling device according to claim 1, wherein a jacket surrounding the terminals is attached to an exterior of the battery case, and a refrigerant circulating device for circulating a liquid refrigerant is provided in the jacket. 3. The non-aqueous electrolyte battery according to 1. 3. The cooling device according to claim 1, wherein the cooling device is provided with a liquid refrigerant flow path in the terminal and a refrigerant circulation device for circulating the refrigerant in the flow path in the terminal. Item 2. The non-aqueous electrolyte battery according to Item 1.