WO1998042039A1

WO1998042039A1 - Sodium-sulfur cell

Info

Publication number: WO1998042039A1
Application number: PCT/JP1997/000839
Authority: WO
Inventors: Yoshimi Sato; Saburo Usami; Tadahiko Miyoshi; Hisamitsu Hato
Original assignee: Hitachi, Ltd.
Priority date: 1997-03-17
Filing date: 1997-03-17
Publication date: 1998-09-24

Abstract

The reliability of a sodium-sulfur cell system is improved by always monitoring the damage of the junction between the cathode cap of a sodium-sulfur cell and the α-alumina of the insulating ring of the cell by sodium and evaluating the remaining life of the cell.

Description

Specification

Technical field of sulfur batteries

The present invention relates to a method for monitoring damage to a power storage system for a natural sulfur battery. In particular, the present invention relates to a natural sulfur suitable for monitoring operation of a joint between an anode cover and an insulating ring due to a sodium of an anode active material and controlling operation thereof. Background art on battery systems

The structure of a conventional sodium-sulfur battery is disclosed in, for example, JP-A-63-26947, JP-A-2-121272 and JP-A-2-126572. The structure uses α-alumina as an insulating ring, and when this insulating ring is hot-pressed to the steel positive and negative electrode container flanges, an oxygen-free copper layer is provided on the α-alumina surface, and nickel After the brazing is applied, heat-welding is performed.The use of corrosion-resistant nickel material improves the corrosion resistance of the heat-welded part, and is used to combine the insulating material with the solid electrolyte tube and the positive electrode with the negative electrode. The positive electrode active material is improved by improving the thermal cycle and corrosion resistance in view of the generation of thermal stress in consideration of the coefficient of thermal expansion, and by forming the concave groove by bending the positive electrode container inward at the entire lower part of the heat-pressed part. It has been devised to prevent the movement of rust and improve the corrosion resistance.

As a method of improving the corrosion resistance by the negative electrode and the positive electrode active material at the interface between the insulating ring and the negative and positive electrode container flange joints, a method of using the material itself as a corrosion-resistant material and a method disclosed in Japanese Patent Application Laid-Open No. 8-45543 are disclosed. A method for improving the corrosion resistance by structurally preventing the liquids of the negative and positive electrode active materials and the mist condensate from adhering to the joint, and a method disclosed in Japanese Patent Application No. 8-5023. As mentioned above, some measures have been taken to improve the corrosion resistance by improving the residual stress at the joint to compressive stress. However, no consideration was given to improving the reliability of the sulfur battery system by monitoring the damage caused by sodium and evaluating the remaining life. Disclosure of the invention

In order to improve the strength reliability of a natural sulfur battery, it is necessary to constantly monitor the joint between the negative electrode cover and α-alumina of the insulating ring due to sodium and evaluate the remaining life. It is effective. It is an object of the present invention to provide a sulfur sulfur battery system in which damage due to the sodium is monitored to improve the strength reliability. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 shows a cross section of a sodium sulfur battery according to the present invention. FIG. 2 shows an outline of a damage crack initiation part by sodium monitored by the present invention and a monitoring method. FIG. 3 shows a damage monitoring battery block operated at a high temperature. Figure 4 shows a damage monitoring battery block operating at high speed. Fig. 5 and Fig. 6 show the location of damage monitoring cells that are hot in one block. FIG. 7 shows a battery system capable of operating at low temperature or at low speed. Fig. 8 shows a battery system that can shut off and switch modules. Fig. 9 shows a battery system with a spare module. FIG. 10 shows a battery system with interchangeable modules. Figure 11 shows the case where a strain gauge is used as a damage detection sensor. Figure 12 shows the relationship between the measured strain range and the length of the damaged crack. Fig. 13 shows a case where a displacement meter is used as a damage detection sensor. Fig. 14 shows a deformation application example where a displacement meter is used as a damage detection sensor. Fig. 15 shows the relationship between the compliance obtained from the deformation behavior and the length of the damaged crack. Figures 16, 17, and 18 show the case where the potential difference method is applied as a damage detection sensor. Fig. 19 and Fig. 20 show the case where AE is applied as a damage detection sensor. Figure 21 shows the relationship between the AE wave and the crack length. Fig. 22 shows an eddy ammeter as a damage detection sensor, and Fig. 23 shows a case of extracting an ultrasonic sensor. Fig. 24 is a diagram showing the installation of a short-circuit detection circuit for a satellite installed on α-alumina. BEST MODE FOR CARRYING OUT THE INVENTION

In order to achieve the present invention, the first invention of the present application is a nutrient sulfur battery characterized by comprising means for monitoring damage of the negative electrode cover and the α-alumina junction by sodium.

The second invention also provides a storage system for a sulfur battery with a plurality of modules, which operates at least one block of the smallest block constituting the module at a higher temperature than the others to prevent damage. A sodium-sulfur battery which is larger than a block battery and has a means for evaluating remaining life by monitoring damage to the battery operated at the high temperature.

Further, in the third invention, the charge or discharge operation of one or more of the minimum blocks constituting the module is performed at a higher speed than another at a different system, so that the damage is greater than that of the other block batteries, A sodium-sulfur battery characterized by comprising means for evaluating remaining life by monitoring damage to the battery.

In addition, the fourth invention provides that, in one or more of the minimum blocks constituting a module, a battery exposed to a higher temperature than other batteries in the block And a means for monitoring damage.

Further, the fifth invention has a means for monitoring the batteries exposed to a higher temperature than the other batteries in the blocks of the blocks of the second and third inventions operated at a high temperature and at a high speed. This is a natural sulfur battery with the following characteristics.

A sixth aspect of the present invention is a sodium-sulfur battery characterized by being able to perform a control operation for suppressing an increase in damage by operating a module having a large damage at a lower temperature than other modules.

A seventh aspect of the present invention is a storage battery system for a sulfur battery, comprising a circuit and a device capable of manually and / or automatically shutting down a circuit for a module having a large damage and performing a switching operation.

According to an eighth aspect of the present invention, in the case of a module having a large damage, the seventh aspect of the present invention installs a switching module battery in advance from the beginning, thereby eliminating time loss required for replacement and enabling efficient operation. This is a power storage system for a sodium-sulfur battery.

The ninth invention is also directed to a means for removing a module having a large damage, introducing a new module and storing a removed battery when manually and / or automatically switching and switching the module according to the seventh invention for a module having a large damage. This is a storage battery for a storage battery that has a space and a spare battery and has the space.

A tenth aspect of the present invention is the sodium sulfur battery according to any one of the first to ninth aspects, wherein a strain gauge installed on the negative electrode lid is used as a sensor for detecting damage.

Further, the eleventh invention is characterized in that, in any of the first to ninth inventions, This is a sodium-sulfur battery that is installed on the negative electrode lid and uses a displacement meter as a sensor for detection.

A twenty-second invention is the sodium-sulfur according to any one of the first to ninth inventions, wherein an electric potential sensor installed between the negative electrode lid or the intermediate material is used for detecting damage. Battery.

According to a thirteenth aspect, in any one of the first to ninth aspects, the damage is detected by using a negative electrode lid or an A-sensor mounted on an α-alumina insulating ring. It is a re-sulfur battery.

A fourteenth invention is the sodium-sulfur battery according to any one of the first to ninth inventions, wherein a vortex battery sensor installed on a negative electrode lid is used to detect damage.

A fifteenth aspect of the present invention is the sodium ion sensor according to any one of the first to ninth aspects, wherein an ultrasonic sensor installed on the negative electrode lid is installed to monitor the damage during operation in order to detect damage. It is a sulfur battery.

A sixteenth aspect of the present invention is the NAT according to the first to ninth aspects, wherein a damage short-circuit detecting circuit is provided inside the insulating ring to detect damage during operation, and the damage during operation is monitored. It is a re-sulfur battery. Also, a seventeenth invention is the sodium-sulfur battery according to the fourth and fifth inventions, wherein a thermocouple is provided on a negative electrode cover for measuring a temperature of a junction.

FIG. 11 shows a strain gauge 12 installed on the negative electrode lid 3 in order to detect a damage crack 11 caused by sodium 5 in claim 10. When the length a of the crack 11 grows, the larger the crack length a becomes at the time of raising or lowering the temperature or charging / discharging, the smaller the rigidity of the negative electrode lid becomes, so that the generated strain range is changed and output. Figure 12 shows the relationship between the change in the strain range △ ε and the crack length a. Behavior. By constantly measuring the strain range εε during operation, it is possible to determine the size a of the crack a damaged by sodium 5, so that the remaining life can be evaluated and the reliability of the battery can be improved.

FIG. 15 shows a construction in which a displacement gauge 13 is provided on the negative electrode lid 3 in order to detect a damage crack 11 caused by sodium 5 in claim 11. When the length a of the crack 11 grows in the same way as when using the strain gauge 12 above, it occurs because the rigidity of the negative electrode lid decreases as the crack length a increases during heating and cooling or discharge. displacement δ and for relationship between the temperature T is smaller rigidity E of unloading process enough _{to t} crack length a which is shown in the first 5 diagram (a) is increased, the crack length a moment opposite the number 1 ZE compliance The relationship shown in Fig. 15 (b) shows the behavior. By constantly measuring the above displacement behavior during operation, it is possible to determine the size of the damage crack a due to sodium 5, so that the remaining life can be evaluated and the reliability of the battery improves.

Similar to the above, in claim 12 the electric differential method is used for the parameters for crack detection, in claim 13 the AE method is used, and in claim 14 the eddy current method is used and the sodium The relationship between the length a of the damaged crack 11 and the length a was clarified by experiments, etc., and a calibration force curve was created. Since the length a can be ascertained, the remaining life of the battery can be evaluated, and the reliability of the battery can be improved. Implementing this for batteries with large damage will improve the strength reliability by conservatively evaluating the remaining life with a smaller number of batteries.

One embodiment of the present invention is shown in FIG. 1 and FIG. The sodium-sulfur battery targeted by the present invention is connected to a solid electrolyte bag tube 1 as shown in FIG. Then, using sodium for the negative electrode active material 5 and sulfur for the positive electrode active material 6, an insulating ring 2 made of α-alumina is installed at the upper opening of the solid electrolyte bag tube 1 to separate the negative electrode and the positive electrode. The structure is such that a negative electrode lid 3 is joined to the insulating ring 2. There is a possibility that a damage crack 11 may be generated in the bonding portion due to the sodium of the negative electrode active material 5. Detecting the damaged crack 11 and constantly monitoring it during operation is an effective means for improving the strength reliability. An object of the present invention is to monitor the damaged crack 11. As a means for detecting the damage crack 11 of the present invention, a damage crack detection sensor 27 is provided on the negative electrode lid 3, and changes depending on the crack length when the temperature of the battery rises or falls, or when discharging or charging. This is a sodium sulfur battery that uses the crack detector 25 to determine the length a of the damaged crack 11 based on the output parameters of the sensor 27 and displays the damaged crack 11 on a monitoring device 26 to constantly monitor it.

Fig. 3 shows an example of applying and applying the damage monitoring means of the present invention to a sodium-sulfur battery power storage system composed of a plurality of modules. One or more blocks among the smallest blocks 30 constituting the module 40 are operated at a higher temperature than the others, and the batteries in the blocks 31 operated at the higher temperature are subjected to the damage cracks 1 1 It is equipped with a means for monitoring damage and constantly monitors for damage cracks. The advantage in this case is that the damage 11 of the battery operated at high temperature is greater than the damage 11 of the other blocks 30. There are benefits that can be secured.

Fig. 4 shows an application or modification of Fig. 3. One or more blocks of the minimum block 30 constituting the module 40 are operated by high-speed discharge or high-speed charge by another system and another system by another system, and the battery in the high-speed block 32 is operated. For monitoring sodium 5 damage 1 1 at said joint It is. The advantage in this case is the damage of the battery operated at high speed 1 1 Force Damage of other blocks 30 1 Larger than that of 1 1 _t Figure 5 there is a main ripple Bok as possible is an embodiment for monitoring efficiently detect damage crack. In a sodium-sulfur battery system composed of a plurality of modules 40, one or more of the minimum blocks 30 constituting the module 40 include one or more other batteries 2 in the block 30 shown in FIG. A case is shown in which, for a battery 21 exposed to a high temperature closer to the heater 23 than 0, means 25 and 26 for monitoring the damage 11 caused by the sodium 5 at the junction are installed. When dry sand 35 is placed between the batteries, the battery 21 at the center becomes hotter than the other batteries 20 as shown in Fig. 6, so the sodium 21 at the junction is attached to the battery 21 at the center. Figure 5 shows the case where means 25 and 26 for monitoring damage 1 caused by 5 are installed.

FIG. 5 is a schematic diagram of a storage battery power storage system composed of a plurality of modules 40, in which a module 45 having a large damage by the damage monitoring means has a lower temperature than other modules 40. This is a natural sulfur battery with a structure that enables low-speed operation in a separate system from operation or other modules 40, and suppresses the progress of battery damage in the module 45 with large damage 11 The advantage is that it can be adjusted to the same level as the damage 11 of other modules 40. There is an advantage that can ensure battery reliability.

FIG. 8 shows an example of a storage battery system for a sulfur battery having a circuit and a device capable of manually or manually disconnecting the highly damaged module 44 from the system circuit and switching and operating the circuit.

Fig. 9 is an application and a modification of Fig. 8. When the circuit of a module with large damage is cut off and the circuit is switched, it is installed as a spare module 43 in advance. Here is an example of a sodium-sulfur battery that can be performed on the module 43. There is a merit that can be switched without lowering the output.

Fig. 10 shows the means for removing the damaged module 41 and introducing a new module 42, the storage space for the removal module 41, and the space for storing the spare module 42. 1 shows an embodiment of a thorium-sulfur battery power storage system. When leading a new module 42, there is an advantage that high temperature can be prepared in advance and high-temperature operation can be performed at the same time as circuit switching, so that operating efficiency does not decrease.

Fig. 11 shows a method for monitoring damage 11 caused by sodium 5 in the joint by installing a strain gauge on the crack detection sensor and calculating the change in strain during operation and during temperature rise and fall △ ε. Shown below is a sodium-sulfur battery that detects and monitors 26 damage caused by sodium 5 in the cell. As shown in Fig. 12, the strain range △ ε shows a behavior in which the rigidity of the negative electrode lid 3 decreases with an increase in the crack length a, so that the deformation becomes large and the strain range becomes large. Pre strain range delta epsilon,, △ a relationship epsilon ₂ when crack length a previously created calibration curve obtained in experiments or the like, can be from the calibration curve to determine the crack from the value output by the strain gauge .

FIGS. 13 and 14 show an embodiment in which a displacement meter is used as the damage detection sensor 13. As shown in Fig. 15, the displacement δ and temperature Τ during temperature rise and fall or during charging and discharging are detected by a thermocouple 37, and as shown in Fig. 15 (a), the rigidity is determined by the relationship between temperature T and displacement δ. Ε is calculated, and the length a of the damaged crack 11 is determined from the calibration curve of the crack length and the reciprocal 1 of the rigidity as shown in Fig. 15 (b). The calibration curve is created in advance by a curve obtained by experiments.

Figures 16 to 18 show examples of applying the potential difference method to damage detection sensors Is shown. Fig. 16 shows the case where the potential of the battery is measured, Fig. 17 shows the embodiment where the potential difference is measured by an external DC power supply, and Fig. 18 shows the embodiment where the potential difference is detected using an AC power supply. Show.

FIG. 19 and FIG. 20 show an embodiment in which AE is used for the damage detection sensor. Crack detection is determined from the characteristics of the AE wave generated during battery temperature rise or fall and charge / discharge as shown in Fig. 21. As shown in Fig. 21 (a), the characteristics of the sound wave are different between 100 ° C or lower where sulfur or sodium solidifies and 100 ° C or higher of liquid. In this embodiment, characteristics at a high temperature of 100 ° C. or more are used. Figure 21 (b) shows the relationship between the crack length a and the number of peak waves, and Figure 21 (c) shows the relationship between the peak wave level and the crack length a. In the present invention, a method was adopted in which both crack lengths a were calculated and displayed on the monitoring device 26. When the second Fig. 2 using eddy current sensor 1 8 for the detection of damage crack, the second 3 figure shows an example of using the ultrasonic sensor 1 9 for the detection of damage Crack _(The second 4 The figure shows a method of monitoring damage 1 caused by sodium 5 at the joint 1 1 by installing an electrical short circuit when sodium 5 intrudes into the α-alumina of the insulating ring 2 and the crack length a during operation. Is a sodium-sulfur battery that can detect more than one point.

According to the present invention, the damage due to the sodium can be quantitatively monitored, and thus there is an effect that the reliability of the joint can be secured. Industrial applicability

ADVANTAGE OF THE INVENTION According to the present invention, it is possible to quantitatively constantly monitor the damage at the joint between the negative electrode cover and the α-alumina of the insulating ring due to the sodium of the negative electrode active material, thereby ensuring the reliability of the joint. In addition, battery operation methods to control damage, battery replacement, and circuit switching timing can be performed more efficiently. Can be applied.

Claims

The scope of the claims

1. Using a solid electrolyte bag tube, sodium is used as the negative electrode active material and sulfur is used as the positive electrode active material. An insulator ring for separating the negative electrode and the positive electrode is installed at the upper opening of the solid electrolyte bag tube. A nutrium-sulfur battery having a structure in which a negative electrode lid is joined to a ring, comprising a means for monitoring damage caused by a nut in a joint between the insulating ring and the negative electrode lid. Mu sulfur battery.

2. One or more of the smallest blocks that make up the module in a natural sulfur battery power storage system composed of multiple modules are operated at a higher temperature than others, and the batteries in the blocks operated at this high temperature for,

2. The sulfur battery as claimed in claim 1, further comprising means for monitoring damage to the joint of the at least one battery by the nursery.

3. One or more of the smallest blocks that make up the module in a natural sulfur battery power storage system composed of multiple modules are operated by another system at a higher rate of discharge or charge than others, and 2. The battery according to claim 1, further comprising means for monitoring, for the batteries in the operated block, at least one battery for damage caused by sodium at the junction. Sulfur battery. ,

4. In one or more of the smallest blocks that make up a module in a storage battery system that is composed of multiple modules, a battery that is exposed to higher temperatures than other batteries in the block 2. The sulfur battery according to claim 1, further comprising means for monitoring at least one of the batteries in the block for damage caused by a stream of the joint.

5. Claims for one or more of the sodium-sulfur batteries according to Claims 2 or 3, wherein the batteries are at a higher temperature or at a higher speed than other batteries. Item 2. A sulfur battery according to Item 1, which is provided with a means for monitoring damage by a joint at a joint.

6. In a natural sulfur battery power storage system composed of a plurality of modules, damage detected by providing a means for monitoring damage by a satellite is greater than damage to other modules. A low-temperature control operation and / or a low-speed discharge and / or low-speed charge control operation can be performed by a separate system for a module having a power storage system.

7. In a natural sulfur battery power storage system composed of multiple modules, by providing a means for monitoring damage caused by sodium, of the detected damage, damage larger than that of other modules can be prevented. A power storage system for a sulfur battery, comprising a circuit and a device capable of manually and / or automatically shutting down and switching operation of a module circuit.

8. In a natural sulfur battery power storage system composed of a plurality of modules, by providing a means for monitoring damage by the nursery, the detected damage is larger than that of other modules. This is a battery system that switches the circuit of a damaged module manually or automatically and switches the module to a module that has been installed as a spare from the beginning, and has the spare module battery. 8. The power storage system according to claim 7, wherein the power storage system is a sulfur battery.

9. In a natural-sulfur battery power storage system composed of a plurality of modules, by providing a means for monitoring damage caused by sodium, a module that is larger than the damage of other modules among the detected damage is provided. When the manual or automatic switching is performed, there is provided a means for removing a module having a large damage and introducing a new module, and a storage space for a removed battery and a space for storing a spare battery. 8. The power storage system for a sodium-sulfur battery according to claim 7.

1. In the sodium-sulfur battery according to any one of claims 1 to 9, a strain gauge is provided on a negative electrode lid as a means for monitoring damage to the joint by the sodium. And a sodium-sulfur battery characterized by monitoring the damage of the joint by sodium during operation or a change in strain during temperature rise and fall.

11. The sodium-sulfur battery according to any one of claims 1 to 9, wherein displacement of the inside and outside of the negative electrode lid is measured as a means for monitoring damage of the junction by sodium. A sodium-sulfur battery characterized by installing a displacement meter capable of monitoring the damage of the joint by sodium from a change in displacement behavior during operation or during temperature rise and fall.

12. The sodium-sulfur battery according to any one of claims 1 to 9, wherein the means for monitoring the joint for damage caused by the sodium is provided on the inside of the negative electrode lid or the joint intermediate material. A sodium-sulfur battery characterized by installing a stop capable of measuring a potential difference between the outside and the outside, and monitoring damage caused by sodium at the connection portion from a change in the potential difference during operation or during temperature rise and fall.

13. The nutrient according to any one of claims 1 to 9. In the Mu sulfur battery, an acoustic emission (AE) sensor is installed on the negative electrode lid or insulating ring as a step to monitor the damage of the junction by sodium, and the AE characteristics during operation and during temperature rise and fall A sodium sulfur battery characterized in that the joint is monitored for damage caused by sodium at a change in the temperature.

14. In the sodium-sulfur battery according to any one of claims 1 to 9, a sensor for detecting eddy current is provided as a means for monitoring damage by the sodium at the junction. The battery is characterized by monitoring the damage caused by sodium at the junction from changes in eddy current during operation.

15. In the sodium-sulfur battery according to any one of claims 1 to 9, an ultrasonic flaw detection sensor is provided on the negative electrode cover as a means for monitoring damage to the junction by sodium. A sodium-sulfur battery characterized by monitoring damage during operation.

16. The sodium-sulfur battery according to any one of claims 1 to 9, wherein sodium is added to the inside of the insulating ring as a means for monitoring the joint for damage caused by sodium. A sodium-sulfur battery characterized by being able to monitor the location of damage cracks during operation at one or more locations by installing a short-circuit detection circuit.

17. The sodium-sulfur battery according to claim 4 or 5, wherein a thermocouple is provided on a negative electrode lid for measuring a temperature of the junction.