Energy storage device

Abstract

The system detects the generation of gas within the battery pack without requiring a sensor to detect the gas concentration. [Solution] The single cell 10 consists of a sulfide-based all-solid-state battery. The busbars 51, 52, and 53 of the battery module 50, in which the single cells 10 are electrically connected in series, are connected to a voltage detection circuit via a printed circuit board 60 equipped with wiring La and wiring Lb. A portion of the wiring Lb is exposed from the insulating coating by a notch (missing portion) 60n of the insulating coating. When the difference between the voltage of the single cell 10 between the wirings La and the single cell voltage between the wirings La and Lb is greater than or equal to a predetermined value, it is determined that the exposed portion of the wiring Lb is corroded by gas generated from the single cell 10, and that gas is being generated from the single cell 10.

Description

Technical Field

[0001] The present disclosure relates to a power storage device.

Background Art

[0002] Japanese Unexamined Patent Application Publication No. 2022 - 12308 (Patent Document 1) discloses a battery system provided with a diagnostic device that diagnoses that a high - concentration abnormality of hydrogen sulfide has occurred when the concentration of a gas containing hydrogen sulfide detected by a gas sensor provided in a battery pack is higher than a threshold concentration.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In Patent Document 1, in order to detect a high - concentration abnormality of hydrogen sulfide, it is necessary to provide a sensor for detecting the concentration of a gas in the battery pack.

[0005] An object of the present disclosure is to enable detection of gas generation in a power storage device without providing a sensor for detecting the concentration of a gas.

Means for Solving the Problems

[0006] The power storage device of the present disclosure includes a battery module and a case that houses the battery module. The battery module includes a single cell having a sulfur component inside, and a wiring electrically connected to the single cell. The wiring includes a first portion whose surface is covered with an insulating member and a second portion whose surface is exposed. The wiring is made of a material that is corroded by hydrogen sulfide in the second portion.

[0007] The energy storage device of this disclosure comprises a battery module and a case housing the battery module. The battery module includes a single cell having a sulfur component inside and wiring electrically connected to the single cell. The wiring comprises a first portion whose surface is covered with an insulating material and a second portion whose surface is exposed. The wiring is made of copper in the second portion. [Effects of the Invention]

[0008] According to this disclosure, it becomes possible to detect the generation of gas in an energy storage device without installing a sensor to detect the gas concentration. [Brief explanation of the drawing]

[0009] [Figure 1] This diagram schematically shows the overall configuration of a vehicle equipped with the battery pack according to this embodiment. [Figure 2] (A) and (B) are schematic diagrams of the battery module configuration. [Figure 3] (A) and (B) are diagrams illustrating the general configuration of a single cell. [Figure 4] This diagram illustrates the schematic configuration of the voltage detection circuit included in the monitoring module. [Figure 5] This figure shows an example flowchart of the gas generation detection process performed by the ECU. [Modes for carrying out the invention]

[0010] The embodiments of this disclosure will be described in detail below with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals, and their descriptions will not be repeated.

[0011] Figure 1 is a schematic diagram showing the overall configuration of a vehicle 100 equipped with a battery pack 200 according to an embodiment of the present disclosure. The vehicle 100 includes a battery pack 200 for storing power for driving. The vehicle 100 is configured to be able to drive using the power stored in the battery pack 200. In this embodiment, the vehicle 100 is an electric vehicle (BEV) without an engine (internal combustion engine), but it may also be a hybrid vehicle (HEV) equipped with an engine, or a plug-in hybrid vehicle (PHEV).

[0012] Vehicle 100 is equipped with an Electronic Control Unit (ECU) 150. The ECU 150 is configured to control the charging and discharging of the battery pack 200. The ECU 150 consists of a processor 151, a Random Access Memory (RAM) 152, and a storage device 153. The RAM 152 functions as working memory to temporarily store data processed by the processor 151. The storage device 153 stores programs as well as information used by the programs (for example, maps, formulas, and various parameters). The processor 151 executes the programs stored in the storage device 153, thereby executing various controls in the ECU 150.

[0013] The monitoring module 130 includes various sensors to detect the status of the battery pack 200 (battery module 50) (for example, voltage, current, and temperature), and outputs the detection results to the ECU 150. The monitoring module 130 is also connected to the printed circuit board 60, which will be described later, and is capable of detecting the voltage of the battery module 50 (single cell 10).

[0014] Vehicle 100 further comprises a drive unit 110, an HMI (Human Machine Interface) device 120, a MIL (Malfunction Indicator Lamp) 125, a hazard lamp 140, an external display 160, and drive wheels W. The drive unit 110 includes a PCU (Power Control Unit) and an MG (Motor Generator) (not shown), and is configured to drive the MG using power stored in the battery pack 200 to propel vehicle 100. The MG is also configured to perform regenerative power generation and supply the generated power to the battery pack 200. The battery pack 200 is rechargeable (externally charged) using power supplied from a charging facility.

[0015] The HMI device 120 includes an input device and a display device. The HMI device 120 may also include a touch panel display. MIL 125 is a warning light located on the instrument panel. The hazard lamps 140 are lamps located on the front, rear, left, and right sides of the vehicle 100, and are the same lamps as turn signals (direction indicators), and function as emergency flashing indicator lights. The external display 160 is, for example, an LED display, and is installed on the rear window, making it possible to view the display content from outside the vehicle 100.

[0016] The battery pack 200 includes a battery case 90 and battery modules 50 housed in the battery case 90. The battery case 90 consists of a lower case 91 and an upper case 92. In this embodiment, two battery modules 50 are housed in the space formed by the lower case 91 and the upper case 92. A desulfurization unit (not shown) equipped with a breathing membrane is attached to the opening 70 of the upper case 92, and the inside and outside of the battery case 90 are in communication via the desulfurization unit. When the internal pressure of the battery case 90 increases, the desulfurization unit discharges air from inside the battery case 90 to the outside. At this time, the desulfurization unit adsorbs hydrogen sulfide from the air. When the internal pressure of the battery case 90 decreases, it takes in outside air. The battery pack 200 is mounted on the floor of the vehicle 100, and may be mounted on the interior side of the vehicle 100 or on the exterior side of the vehicle 100.

[0017] Figure 2 shows the schematic configuration of the battery module 50. Figure 2(A) is a top view of the battery module 50, and Figure 2(B) is an enlarged view of section F in Figure 2(A). The battery module 50 is a battery pack in which multiple individual cells 10 are electrically connected in series. The multiple individual cells 10 are stacked between a pair of end plates 30.

[0018] Figure 3 is a diagram illustrating the schematic configuration of the single cell 10 in this embodiment. Figure 3(A) is a top view of the single cell 10. The single cell 10 is a laminated all-solid-state battery using a laminate film as the outer casing member 20, and a negative electrode terminal (negative electrode tab) 1a and a positive electrode terminal (positive electrode tab) 5a extend from the outer casing member 20. One of the negative electrode terminal 1a and the positive electrode terminal 5a corresponds to the "first electrode terminal" of this disclosure, and the other corresponds to the "second electrode terminal" of this disclosure. The laminate film may be, for example, a pouch made of aluminum laminate film, or a three-layer film with aluminum foil sandwiched between resin films.

[0019] FIG. 3(B) shows the all-solid-state battery laminate 15 housed in the exterior member 20, and shows the B-B cross section of FIG. 3(A). The all-solid-state battery laminate 15 includes an all-solid-state battery element 8 in which a negative electrode current collector layer 1, a negative electrode active material layer 2, a solid electrolyte layer 3, a positive electrode active material layer 4, and a positive electrode current collector layer 5 are laminated in this order. The all-solid-state battery element 8 shares the negative electrode current collector layer 1 and the positive electrode current collector layer 5, and three of them are laminated with the lamination order reversed. The negative electrode current collector layer 1 is connected to the negative electrode terminal 1a, and the positive electrode current collector layer 5 is connected to the positive electrode terminal 5a. Note that the number of all-solid-state battery elements 8 included in the all-solid-state battery laminate 15 may be one or four or more. The insulating film 7 insulates between the all-solid-state battery laminate 15 and the exterior member (laminate film) 20. The all-solid-state battery laminate 15 or the all-solid-state battery element 8 corresponds to an example of the "power generation element" of the present disclosure. After housing the all-solid-state battery laminate 15 in the exterior member (laminate film) 20, the outer periphery (peripheral portion) of the exterior member 20 is joined by heat welding (heat fusion) to seal the all-solid-state battery laminate 15. Thereby, a seal portion is formed on the outer periphery of the exterior member.

[0020] The single cell 10 is a sulfide-based all-solid-state battery. In the present disclosure, the sulfide-based all-solid-state battery contains a sulfur component in at least one of the materials of the positive electrode active material layer 4 or the solid electrolyte layer 3. In the present embodiment, the solid electrolyte layer 3 contains a sulfide-based solid electrolyte. For example, the sulfide-based solid electrolyte may be made from phosphorus pentasulfide (P2S5) and lithium sulfide (Li2S) as starting materials. In this case, the positive electrode active material layer 4 may contain, for example, lithium cobaltate, lithium nickelate, lithium iron phosphate, or the like. When the solid electrolyte layer 3 is composed of an oxide-based solid electrolyte, a sulfur-based positive electrode active material is used for the positive electrode active material layer 4. The sulfur-based positive electrode active material may be an organic sulfur compound or an inorganic sulfur compound. Note that both the solid electrolyte layer 3 and the positive electrode active material layer 4 may contain a sulfur component.

[0021] Referring to FIG. 2, a plurality (n) of single cells 10 are arranged and stacked between a pair of end plates 30. The single cells 10 are sandwiched between the pair of end plates 30 in a stacked state, and a predetermined restraint load is applied by a restraint band or the like (not shown). Adjacent single cells 10 are electrically connected in series by a bus bar 51 such that the negative electrode terminals 1a and the positive electrode terminals 5a are connected. In FIG. 2, 12 single cells 10 are connected in series, but the number of single cells 10 may be any number. In FIG. 2(A), a bus bar 52 is connected to the positive electrode terminal 5a of the single cell 10 located on the leftmost side, and a bus bar 53 is connected to the negative electrode terminal 1a of the single cell 10 located on the rightmost side. When connecting two battery modules 50 in series, one of the bus bar 52 and the bus bar 53 is connected to the other battery module 50, and the other is connected to the output terminal. When connecting two battery modules 50 in parallel, the bus bar 52 and the bus bar 53 are connected to the output terminals.

[0022] The battery module 50 is provided with a printed circuit board 60 including wirings connected to the bus bars 51, 52, and 53. The printed circuit board 60 is, for example, a flexible printed circuit (FPC), in which a wiring made of a conductor foil (for example, a copper foil) is provided on the surface of a base film via an adhesive layer, and the wiring is covered with an insulating film (cover layer). As shown in FIG. 2(B), a plurality of wirings La and a plurality of wirings Lb are provided on the printed circuit board 60. The wiring La is a wiring in which all of the wirings (for example, copper foils) are covered with an insulating film, and is indicated by a broken line. The wiring Lb is a wiring in which a part of the wiring is exposed from the insulating film. The exposed part of the wiring (hereinafter also referred to as an exposed portion) is indicated by a solid line, and the wiring covered with the insulating film is indicated by a broken line. The exposed portion of the wiring Lb may be thinner than the portion of the wiring La and the wiring Lb covered with the insulating film. The exposed portion of the wiring Lb may be formed by providing a notch (missing portion) 60n in the insulating film.

[0023] Referring to Figure 2(B), the busbar 52 is connected to the wiring La(La-1) of the printed circuit board 60 via the connector 61. This wiring La(La-1) is connected to the positive terminal 5a of the rightmost cell 10(10-1) via the busbar 52. This wiring La(La-1) corresponds to the "first wiring" in this disclosure. The busbar 51(51-1) connecting the negative terminal 1a of cell 10(10-1) and the positive terminal 5a of cell 10(10-2) adjacent to cell 10(10-1) is connected to the wiring La(La-2) and wiring Lb(Lb-1) via the connector 62. These wires La (La-2) and Lb (Lb-1) are connected via busbar 51 (51-1) to the negative terminal 1a of cell 10 (10-1) and the positive terminal 5a of cell 10 (10-2). Wire La (La-2) corresponds to the "second wire" of this disclosure, and wire Lb (Lb-1) corresponds to the "third wire" of this disclosure.

[0024] A busbar 51(51-2) connecting the negative terminal 1a of cell 10(10-2) and the positive terminal 5a of cell 10(10-3) adjacent to cell 10(10-2) has a wiring La(La-3) connected to it via a connector 61. This wiring La(La-3) is connected to the negative terminal 1a of cell 10(10-2) and the positive terminal 5a of cell 10(10-3) via the busbar 51(51-2). This wiring La(La-3) corresponds to the "first wiring" in this disclosure.

[0025] A busbar 51 (51-3) connects the negative terminal 1a of cell 10 (10-3) to the positive terminal 5a of cell 10 (10-4) adjacent to cell 10 (10-3). A connector 62 connects the busbar 51 (51-3) to the wiring La (La-4) and the wiring Lb (Lb-2). These wirings La (La-4) and Lb (Lb-2) are connected to the negative terminal 1a of cell 10 (10-3) and the positive terminal 5a of cell 10 (10-4) via the busbar 51 (51-3). This wiring La (La-4) corresponds to the "second wiring" in this disclosure, and the wiring Lb (Lb-2) corresponds to the "third wiring" in this disclosure. Hereafter, the busbars 51 and 53 are connected to the wirings La and Lb in a similar configuration, and the printed circuit board 60 is connected to the monitoring module 130.

[0026] Figure 4 is a diagram illustrating the schematic configuration of the voltage detection circuit 131 provided in the monitoring module 130. This voltage detection circuit 131 also functions as an equalization unit that equalizes the voltage of the single cell 10. The monitoring module 130 or the voltage detection circuit 131 corresponds to an example of a "detection device" in this disclosure. The voltage detection circuit 131 is connected to wiring La and wiring Lb of the printed circuit board 60.

[0027] The voltage detection circuit 131 detects the voltage of the cell 10 via multiple voltage detection lines L1, branch line L11, and branch line L12. Voltage detection line L1 is connected to the positive terminal of cell 10 (10-1) and the negative terminal of cell 10 (10-n) (more specifically, bus bars 52, 53) via wiring La of the printed circuit board 60. In addition, voltage detection line L1 is connected between cell 10 (10-1) and cell 10 (10-n) to the negative terminal of one cell and the positive terminal of the other cell (more specifically, bus bar 51) via wiring La or wiring Lb of the printed circuit board 60.

[0028] Between the single cell 10(10-1) and the single cell 10(10-n), a busbar 51(51-1, 51-3, ...) to which wiring La and wiring Lb are connected, and a voltage detection line L1 is connected to a switch S1, which is configured to selectively switch between the connection between the voltage detection line L1 and wiring La, and the connection between the voltage detection line L1 and wiring Lb.

[0029] The voltage detection line L1 is equipped with a fuse F and a chip bead Cb. The fuse F blows when an overcurrent occurs, protecting the circuit. The chip bead Cb reduces applied stress when a surge voltage is applied instantaneously.

[0030] A Zener diode D is connected in parallel to the single cell 10 via a voltage detection line L1. The cathode of the Zener diode D is connected to the positive terminal of the corresponding single cell, and the anode is connected to the negative terminal of the corresponding single cell. When an overvoltage is applied from the battery module 50 (single cell 10) to the voltage detection circuit 131, current flows through the Zener diode D, protecting the voltage detection circuit 131 from the overvoltage.

[0031] The voltage detection line L1 branches into branch line L11 and branch line L12 on the monitoring module 130 side from the Zener diode D. Branch line L11 is connected to comparator 131a via switch So, and branch line L12 is connected to comparator 131a via switch Sh. Switches So and Sh can be, for example, photoMOS (Metal Oxide Semiconductor) relays. Note that branch line L11, which branches off from the voltage detection line L1 connected to the positive terminal (busbar 52) of the single cell 10 (10-1) located on the positive output terminal side of the battery module 50, is not connected to comparator 131a. Also, the voltage detection line L1 connected to the negative terminal of the single cell 10 (10-n) located on the negative output terminal side of the battery module 50 does not have branch line L12.

[0032] A resistor R1 is provided in the branch line L12. A capacitor (flying capacitor) C is provided between the branch line L12, which is connected to the positive terminal of each cell 10, and the branch line L11, which is connected to the negative terminal. In the branch line L12, the capacitor C is connected between the resistor R1 and the switch Sh, and the resistor R1 and the capacitor C form an RC low-pass filter. The capacitor C is connected in parallel with the corresponding cell 10, and the charge of the corresponding cell 10 charges the capacitor C, so that the voltage value of the capacitor C becomes equal to the voltage value of the corresponding cell 10. By turning ON (closing) the switches Sh and So corresponding to a specific cell 10, the comparator 131a outputs the voltage of that specific cell 10. As a result, the monitoring module 130 can detect the voltage of each cell 10 using the voltage detection circuit 131 by sequentially turning ON the switches Sh and So corresponding to each cell 10.

[0033] The voltage detection circuit 131 includes a discharge resistor Rd provided on the branch line L11 and a switch S1 that conducts (closes) / interrupts (opens) the connection between adjacent branch lines L11, thus performing the function of an equalization unit. For example, by closing the switch S1 corresponding to a single cell 10 with a higher voltage than the reference voltage, the current discharged from that single cell 10 is consumed by the discharge resistor Rd, thereby equalizing the voltage of the single cell 10.

[0034] In the single cell 10, for example, there is a concern that air may enter from the sealing area of ​​the outer casing member 20 (laminate film). In particular, the negative electrode terminal 1a and positive electrode terminal 5a (electrode tab) extend from the sealing area of ​​the outer casing member 20, and the outer casing member (laminate film) 20 is joined and sealed so as to sandwich the negative electrode terminal 1a and the positive electrode terminal 5a, making it easy for air to enter from the sealing area of ​​the sealing part. If the entered air contains moisture, the sulfur component contained in the solid electrolyte layer 3 or the positive electrode active material layer 4 will react with the moisture to generate hydrogen sulfide, which may be released into the battery case 90. In this embodiment, the generation of hydrogen sulfide is detected by utilizing the fact that the exposed portion of the wiring Lb corrodes due to hydrogen sulfide, and its conductivity changes.

[0035] Figure 5 shows an example of a flowchart of the gas generation detection process performed by the ECU 150. This flowchart may be processed at predetermined intervals. For example, it may be processed when the power switch of the vehicle 100 is turned ON, at predetermined intervals while the vehicle 100 is running, or when external charging of the battery pack 200 (battery module 50) begins. In step 10 (hereinafter, steps are abbreviated as "S"), the switch S2 of the voltage detection circuit 131 is switched to wiring Lb. This connects wiring Lb and voltage detection line L1. Subsequently, in S11, after switching switch S2 to wiring Lb, after a set time has elapsed, switches Sh and So corresponding to each cell 10 are sequentially turned ON to detect the voltage VBb of each cell 10.

[0036] In S12, switch S2 of the voltage detection circuit 131 is switched to wiring La. This connects wiring La to the voltage detection line L1. Subsequently, in S13, after switching switch S2 to wiring La, after a set time has elapsed, switches Sh and So corresponding to each cell 10 are sequentially turned ON to detect the voltage VBa of each cell 10.

[0037] In the subsequent S14, after calculating the maximum value (maximum value) MAXΔVB of the difference (|VBa - VBb|) between the voltages VBa and VBb of each single battery 10, the process proceeds to S15. In S15, it is determined whether the maximum value MAXΔVB is equal to or greater than a predetermined value A. If the maximum value MAXΔVB is less than the predetermined value A (MAXΔVB < A), a negative determination is made and the current routine ends.

[0038] If the maximum value MAXΔVB is equal to or greater than the predetermined value A (MAXΔVB ≥ A), an affirmative determination is made and the process proceeds to S16. In S16, it is determined that hydrogen sulfide (gas) is generated from the single battery 10. Also, to notify the generation of hydrogen sulfide, MIL125 is lit, a message indicating "Battery abnormality" is displayed on the display device of the HMI device 120, the hazard lamp 140 is blinked, and a message indicating "Attention (hydrogen sulfide)" is displayed on the external display 160.

[0039] When hydrogen sulfide is generated and released in the single battery 10, the exposed portion of the wiring Lb is corroded by hydrogen sulfide, its conductivity changes, for example, the resistance value of the wiring Lb increases. Therefore, when the exposed portion of the wiring Lb is corroded by hydrogen sulfide, the difference in the time constant of the RC circuit including the capacitor C between the voltage detection line L1 connected to the wiring La and the voltage detection line L1 connected to the wiring Lb increases. Thus, when the difference between the voltage VBa detected using the wiring La and the voltage VBb detected using the wiring Lb increases and the maximum value MAXΔVB is equal to or greater than the predetermined value A, it can be determined that hydrogen sulfide is generated from the single battery 10, and the generation of hydrogen sulfide can be detected.

[0040] When the above gas generation detection process is not being executed, the ECU150 selects the switching of the switch S2 so as to always connect the wiring La and the voltage detection line L1. Thereby, the voltage detected using the wiring La is adopted as the voltage value of each single battery 10, and various controls such as battery control can be executed.

[0041] According to the above embodiment, the battery module 50 comprises a single cell 10 made of a sulfide-based solid battery including a negative electrode terminal 1a and a positive electrode terminal 5a, and a printed circuit board 60 including wiring connected to the negative electrode terminal 1a and the positive electrode terminal 5a. The printed circuit board 60 has wiring La connected to one of the negative electrode terminal 1a and the positive electrode terminal 5a, and wiring La and wiring Lb connected to the other of the negative electrode terminal 1a and the positive electrode terminal 5a. Wiring La and wiring Lb are covered with an insulating film, and the portion of wiring Lb adjacent to the negative electrode terminal 1a or the positive electrode terminal 5a is exposed from the insulating film. The exposed portion of wiring Lb is exposed to hydrogen sulfide (gas) generated from the single cell 10. Therefore, when hydrogen sulfide is generated from the single cell 10, the exposed portion of wiring Lb is corroded by the hydrogen sulfide. As a result, the conductivity of wiring Lb changes, and by detecting this change, it becomes possible to detect hydrogen sulfide generated from the single cell 10 without providing a sensor to detect the gas concentration. Furthermore, if the exposed portion of wiring Lb is thinner than the portion covered by the insulating coating of wiring La and wiring Lb, the corrosion effect of hydrogen sulfide on the exposed portion will be greater. This will result in a greater change in the conductivity of the exposed portion due to corrosion, making it easier to detect the gas generated from the single cell 10.

[0042] According to the above embodiment, the single cell 10 is a laminate-type all-solid-state battery in which the outer casing member 20 is made of laminate film, and a negative electrode terminal (negative electrode tab) 1a and a positive electrode terminal (positive electrode tab) 5a extend from the outer casing member 20. Hydrogen sulfide generated in the single cell 10 is likely to leak out from the seal portion between the negative electrode terminal 1a and the positive electrode terminal 5a and the outer casing member (laminated film) 20. The exposed portion of the wiring Lb adjacent to the negative electrode terminal 1a or the positive electrode terminal 5a is exposed to the gas leaked from the seal portion, so the change in conductivity of the exposed portion due to corrosion becomes large, and the gas generated from the single cell 10 can be detected well.

[0043] According to the above embodiment, the ECU 150 uses the voltage detection circuit 131 of the monitoring module 130 connected to the printed circuit board 60 to detect corrosion of the exposed portion of the wiring Lb, and determines that hydrogen sulfide is being generated from the single cell 10. This makes it possible to detect hydrogen sulfide generated from the single cell 10 using the voltage detection circuit 131 of the monitoring module 130 without providing a sensor to detect the gas concentration.

[0044] According to the above embodiment, the ECU 150 determines that hydrogen sulfide is being generated when the difference between the voltage VBa, which is the voltage of a single cell 10 detected using wiring La, and the voltage VBb detected using wiring La and wiring Lb is greater than or equal to a predetermined value A. As a result, the voltage detection circuit 131 can detect hydrogen sulfide being generated from the single cell 10, and the voltage detection circuit 131 can adopt the voltage detected using wiring La as the voltage value of each single cell 10 and perform various controls such as battery control.

[0045] In the above embodiment, the voltages VBa and VBb of each individual cell 10 were detected to detect the generation of hydrogen sulfide. Alternatively, the voltages of multiple (for example, 2 to 6) individual cells 10 connected in series may be detected in the same manner as in the above embodiment to detect the generation of hydrogen sulfide. Furthermore, the voltage of the battery module 50 (the voltage between busbars 52 and 53) may be detected in the same manner as in the above embodiment to detect the generation of hydrogen sulfide.

[0046] In the above embodiment, the voltage detection circuit 131 used a capacitor (flying capacitor) C to detect the voltage of the single cell 10. However, the voltage of the single cell 10 may be detected without using capacitor C. In this case, the exposed portion of the wiring Lb may corrode, increasing its resistance, for example, so it is sufficient to detect a voltage difference corresponding to that resistance. Alternatively, instead of providing a switch S2, two voltage detection circuits may be provided, and each voltage detection circuit may detect the voltage VBa and the voltage VBb of the single cell 10.

[0047] In the above embodiment, an example was described in which the battery pack 200 (battery module 50) is mounted on a vehicle 100. The battery pack 200 may also be a stationary energy storage device.

[0048] The embodiments disclosed herein should be considered in all respects to be illustrative and not restrictive. The scope of this disclosure is indicated by the claims rather than by the description of the embodiments above, and all modifications within the meaning and scope equivalent to the claims are intended to be included. [Explanation of Symbols]

[0049] 1 Negative electrode current collector layer, 1a Negative electrode terminal, 2 Negative electrode active material layer, 3 Solid electrolyte layer, 4 Positive electrode active material layer, 5 Positive electrode current collector layer, 5a Positive electrode terminal, 7 Insulating film, 8 All-solid-state battery element, 10 Single cell, 15 All-solid-state battery laminate, 20 Outer casing, 30 End plate, 50 Battery module, 51, 52, 53 Busbars, 60 Printed circuit board, 90 Battery case, 100 Vehicle, 110 Driving unit, 120 HMI device, 125 MIL, 130 Monitoring module, 131 Voltage detection circuit, 140 Hazard lamp, 150 Control unit (ECU), L1 Voltage detection line, La, Lb Wiring, S1, S2, So, Sh Switches.

Claims

1. A power storage device comprising a battery module and a case for housing the battery module, The aforementioned battery module is A single cell containing sulfur components inside, The single cell and the wiring electrically connected thereto, The aforementioned wiring comprises a first portion whose surface is covered with an insulating material and a second portion whose surface is exposed. The aforementioned wiring is made of a material that corrodes with hydrogen sulfide in the second part of the energy storage device.

2. A power storage device comprising a battery module and a case for housing the battery module, The aforementioned battery module is A single cell containing sulfur components inside, The single cell and the wiring electrically connected thereto, The aforementioned wiring comprises a first portion whose surface is covered with an insulating material and a second portion whose surface is exposed. The aforementioned wiring is made of copper in the second portion, in the energy storage device.

3. The energy storage device according to claim 1 or claim 2, wherein the thickness of the second portion of the wiring is thinner than the thickness of the first portion.

4. The case has an opening that connects the inside and outside of the case, The energy storage device according to claim 1 or claim 2, wherein a desulfurization unit for adsorbing hydrogen sulfide is provided in the opening.

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