Power storage cell

Abstract

To suppress an increase of space occupied by power storage cells equipped with detection units that perform wireless communication.SOLUTION: A power storage cell 100 includes an outer body 90, a main body 50, and a detection unit 500. The main body 50 is located inside the outer body 90. The detection unit 500 is located at least partially inside the outer body 90, detects the state of the power storage cell, and communicates wirelessly.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present technology relates to an electricity storage cell. [Background technology]

[0002] A prior art document disclosing the configuration of a battery monitoring device is JP 2020-27767 A (Patent Document 1). The battery monitoring device described in Patent Document 1 includes a detection board mounted on a battery module. The detection board has a detection circuit that detects status information of the battery module, a wireless circuit, and an antenna that wirelessly transmits status information of the battery module. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-27767 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the battery monitoring device described in Patent Document 1, a detection board is mounted on the battery module, which increases the space occupied by the device. In addition, space is required to place a power source to supply power to the detection board, which increases the space occupied by the device.

[0005] An object of the present technology is to provide an electricity storage cell including a detection unit that wirelessly communicates while suppressing an increase in the space it occupies. [Means for solving the problem]

[0006] According to a first aspect of the present technology, there is provided an energy storage cell including an exterior body, a main body, and a detection unit. The main body is disposed inside the exterior body. The detection unit is at least partially disposed inside the exterior body, and detects a state of the energy storage cell and communicates wirelessly.

[0007] A storage cell according to a second aspect of the present technology includes a main body, a current collector, and a detection unit. The current collector is connected to the main body. The detection unit is electrically connected to the current collector to receive power, detects a state of the storage cell, and communicates wirelessly. Effect of the Invention

[0008] According to the present technology, it is possible to suppress an increase in the space occupied by a power storage cell including a detection unit that wirelessly communicates. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a diagram showing a basic configuration of a battery pack. [Diagram 2] FIG. 2 is a diagram showing battery cells and end plates included in a battery pack. [Diagram 3] FIG. 2 is a diagram showing a battery cell in a battery pack. [Figure 4] 4 is a cross-sectional view taken along the line IV-IV in FIG. 3. [Diagram 5] 2 is a schematic diagram showing an example of the configuration of an electrode body in the present embodiment. FIG. [Figure 6] FIG. 4 is a circuit diagram showing the electrical connection between the battery cell and the detection unit. [Figure 7] FIG. 4 is a functional block diagram showing a specific example of a detection unit. [Figure 8] 13 is a partial cross-sectional view showing the periphery of an antenna portion of a battery cell according to a first modified example of the first embodiment. [Figure 9] 13 is an exploded perspective view showing the configuration of a detection unit and an exterior body of a battery cell according to a second modified example of the first embodiment. FIG. [Figure 10] 13 is a partial cross-sectional view showing the configuration of a detection unit for a battery cell according to a first modified example of the first embodiment. FIG. [Figure 11] 11 is a plan view showing the external appearance of a battery cell according to embodiment 2. FIG. [Figure 12] FIG. 11 is an exploded perspective view showing the configuration of a battery cell according to a second embodiment. [Figure 13]13 is a plan view showing the appearance of a battery cell according to a modified example of the second embodiment. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, embodiments of the present technology will be described. Note that the same or corresponding parts are denoted by the same reference characters, and description thereof will not be repeated.

[0011] In the embodiments described below, when numbers, amounts, etc. are mentioned, unless otherwise specified, the scope of the present technology is not necessarily limited to the numbers, amounts, etc. In addition, in the embodiments described below, each component is not necessarily essential to the present technology, unless otherwise specified.

[0012] In this specification, the words "comprise", "include", and "have" are open-ended. In other words, when a certain configuration is included, other configurations may or may not be included. In addition, the present technology is not limited to those that necessarily achieve all of the effects and advantages mentioned in the present embodiment.

[0013] In this specification, the term "battery" is not limited to a lithium ion battery, but may include other batteries such as nickel-metal hydride batteries. In this specification, the term "electrode" may collectively refer to positive and negative electrodes. Furthermore, the term "electrode plate" may collectively refer to positive and negative plates. The term "current collector" may collectively refer to positive and negative current collectors.

[0014] In this specification, the terms "energy storage cell" and "energy storage module" are not limited to battery cells and battery modules, but may include capacitor cells and capacitor modules.

[0015] (Embodiment 1) Fig. 1 is a diagram showing the basic configuration of a battery pack 1. Fig. 2 is a diagram showing battery cells 100 and end plates 200 included in the battery pack 1.

[0016] As shown in FIGS. 1 and 2, a battery pack 1, which is an example of a “power storage module”, includes battery cells 100, end plates 200, binding members 300, and resin plates 400.

[0017] The multiple battery cells 100 are arranged so as to be aligned in the Y-axis direction (arrangement direction). This forms a stack of the battery cells 100. Separators (not shown) are interposed between the multiple battery cells 100. The multiple battery cells 100 sandwiched between the two end plates 200 are pressed by the end plates 200 and are restrained between the two end plates 200.

[0018] The end plates 200 are disposed on both ends of the battery pack 1 in the Y-axis direction. The end plates 200 are fixed to a base such as a case that houses the battery pack 1. Step portions 210 are formed on both ends of the end plates 200 in the X-axis direction (width direction).

[0019] The restraining member 300 connects the two end plates 200 to each other. The restraining member 300 is attached to a step portion 210 formed on each of the two end plates 200.

[0020] When a compressive force in the Y-axis direction is applied to the stack of multiple battery cells 100 and end plates 200, the restraining member 300 is engaged with the end plates 200, and the compressive force is then released, causing a tensile force to act on the restraining member 300 connecting the two end plates 200. In reaction to this, the restraining member 300 presses the two end plates 200 in a direction that brings them closer to each other.

[0021] The restraining member 300 includes a first member 310 and a second member 320. The first member 310 and the second member 320 are joined to each other by, for example, butt welding. A tip surface formed by folding back the second member 320 abuts against the step portion 210 of the end plate 200 from the Y-axis direction.

[0022] Fig. 3 is a diagram showing a battery cell 100 in the battery pack 1. Fig. 4 is a cross-sectional view seen from the direction of the arrows IV-IV in Fig. 3. As shown in Fig. 3 and Fig. 4, the battery cell 100 includes an exterior body 90, an electrode body 50, a positive terminal 81, a negative terminal 82, a positive current collecting member 71, and a negative current collecting member 72.

[0023] The exterior body 90 is rectangular (flattened rectangular parallelepiped). However, the rectangular shape is just one example. The exterior body 90 may have any shape. The exterior body 90 may be cylindrical or pouch-shaped, for example. The exterior body 90 may be made of an Al alloy, for example. The exterior body 90 houses the electrode body 50 and an electrolyte (not shown). The exterior body 90 may include, for example, a sealing plate 91 and an exterior can 92. The exterior can 92 has an opening. The sealing plate 91 seals the opening of the exterior can 92. The sealing plate 91 and the exterior can 92 may be joined by, for example, laser welding.

[0024] A positive electrode terminal 81 and a negative electrode terminal 82 are provided on a sealing plate 91. The positive electrode terminal 81 is fixed to the sealing plate 91 via a resin insulating member 61. The negative electrode terminal 82 is fixed to the sealing plate 91 via a resin insulating member 62.

[0025] The positive electrode terminal 81 is preferably made of a metal, more preferably made of aluminum or an aluminum alloy. The negative electrode terminal 82 is preferably made of a metal, more preferably made of copper or a copper alloy. The negative electrode terminal 82 may be configured to have a region made of copper or a copper alloy located on the inside side of the exterior body 90 and a region made of aluminum or an aluminum alloy located on the outside side of the exterior body 90.

[0026] The sealing plate 91 may further include an injection port 41 and a gas exhaust valve 42. An electrolyte may be injected into the exterior body 90 from the injection port 41. The gas exhaust valve 42 breaks when the pressure inside the exterior body 90 reaches or exceeds a threshold value. This allows the flammable gas inside the exterior body 90 to be exhausted to the outside of the exterior body 90. A current collector is connected to the electrode body 50. Specifically, the electrode body 50 is connected to a positive terminal 81 by a positive current collector 71. The positive current collector 71 may be, for example, an Al plate. The electrode body 50 is connected to a negative terminal 82 by a negative current collector 72. The negative current collector 72 may be, for example, a Cu plate.

[0027] FIG. 5 is a schematic diagram showing an example of the configuration of the electrode body in this embodiment. The electrode body 50, which is the main body of the battery cell 100, is disposed inside the exterior body 90. The electrode body 50 is a wound type. The electrode body 50 includes a positive electrode 10, a separator 30, and a negative electrode 20. That is, the battery cell 100 includes a positive electrode 10, a negative electrode 20, and an electrolyte. The positive electrode 10, the separator 30, and the negative electrode 20 are all strip-shaped sheets. The electrode body 50 may include a plurality of separators 30. The electrode body 50 is formed by stacking the positive electrode 10, the separator 30, and the negative electrode 20 in this order and winding them in a spiral shape. Either the positive electrode 10 or the negative electrode 20 may be sandwiched between the separators 30. Both the positive electrode 10 and the negative electrode 20 may be sandwiched between the separators 30. The electrode body 50 may be formed into a flat shape after winding. The wound type is an example. The electrode body 50 may be, for example, a stack type.

[0028] The positive electrode 10 includes a positive electrode substrate 11 and a positive electrode active material layer 12. The positive electrode substrate 11 is a conductive sheet. The positive electrode substrate 11 may be, for example, an Al alloy foil. The positive electrode substrate 11 may have a thickness of, for example, 10 μm to 30 μm. The positive electrode active material layer 12 is disposed on a surface of the positive electrode substrate 11. The positive electrode active material layer 12 may be disposed on only one surface of the positive electrode substrate 11. The positive electrode active material layer 12 may be disposed on both the front and rear surfaces of the positive electrode substrate 11. The positive electrode substrate 11 may be exposed at one end in the width direction of the positive electrode 10 (the X-axis direction in FIG. 5). A positive electrode current collecting member 71 may be joined to the exposed portion of the positive electrode substrate 11.

[0029] For example, an intermediate layer (not shown) may be formed between the positive electrode active material layer 12 and the positive electrode substrate 11. In the present embodiment, even when an intermediate layer is present, the positive electrode active material layer 12 is considered to be disposed on the surface of the positive electrode substrate 11. The intermediate layer may be thinner than the positive electrode active material layer 12. The intermediate layer may have a thickness of, for example, 0.1 μm to 10 μm. The intermediate layer may include, for example, a conductive material, an insulating material, or the like.

[0030] The positive electrode active material layer 12 may have a thickness of, for example, 10 μm to 200 μm. The positive electrode active material layer 12 may have a thickness of, for example, 50 μm to 150 μm. The positive electrode active material layer 12 may have a thickness of, for example, 50 μm to 100 μm.

[0031] The positive electrode active material layer 12 includes a positive electrode active material. The positive electrode active material is a particle group. The positive electrode active material layer 12 may further include additional components as long as it includes a positive electrode active material. The positive electrode active material layer 12 may include, in addition to the positive electrode active material, for example, a conductive material and a binder. The conductive material may include any component. The conductive material may include, for example, at least one selected from the group consisting of carbon black, graphite, vapor grown carbon fiber (VGCF), carbon nanotubes (CNT), and graphene flakes. The blending amount of the conductive material may be, for example, 0.1 parts by mass to 10 parts by mass with respect to 100 parts by mass of the positive electrode active material. The binder may include any component. The binder may include, for example, at least one selected from the group consisting of polyvinylidene fluoride (PVdF), poly(vinylidene fluoride-co-hexafluoropropylene (PVdF-HFP), polytetrafluoroethylene (PTFE), and polyacrylic acid (PAA). The amount of the binder may be, for example, 0.1 to 10 parts by mass with respect to 100 parts by mass of the positive electrode active material.

[0032] The positive electrode active material layer 12 may have a high density. For example, the positive electrode active material layer 12 may have a density of 3.6 g / cm 3 from 3.9 g / cm 3 The positive electrode active material layer 12 may have a density of, for example, 3.65 g / cm 3 from 3.81 g / cm 3 The positive electrode active material layer 12 may have a density of, for example, 3.70 g / cm 3 from 3.81 g / cm 3 In this specification, the density of the active material layer refers to the apparent density.

[0033] The negative electrode 20 may include, for example, a negative electrode substrate 21 and a negative electrode active material layer 22. The negative electrode substrate 21 is a conductive sheet. The negative electrode substrate 21 may be, for example, a Cu alloy foil. The negative electrode substrate 21 may have a thickness of, for example, 5 μm to 30 μm. The negative electrode active material layer 22 may be disposed on the surface of the negative electrode substrate 21. The negative electrode active material layer 22 may be disposed on only one surface of the negative electrode substrate 21. The negative electrode active material layer 22 may be disposed on both the front and rear surfaces of the negative electrode substrate 21. The negative electrode substrate 21 may be exposed at one end in the width direction (X-axis direction in FIG. 5) of the negative electrode 20. A negative electrode current collecting member 72 may be joined to the exposed portion of the negative electrode substrate 21.

[0034] The negative electrode active material layer 22 may have a thickness of, for example, 10 μm to 200 μm. The negative electrode active material layer 22 includes a negative electrode active material. The negative electrode active material may include any component. The negative electrode active material may include at least one selected from the group consisting of, for example, graphite, soft carbon, hard carbon, silicon, silicon oxide, a silicon-based alloy, tin, tin oxide, a tin-based alloy, and a lithium titanium composite oxide.

[0035] The negative electrode active material layer 22 may further contain, for example, a binder in addition to the negative electrode active material. The negative electrode active material layer 22 may contain, for example, 95% to 99.5% by mass of the negative electrode active material, with the remainder being a binder. The binder may contain any component. The binder may contain, for example, at least one selected from the group consisting of carboxymethyl cellulose (CMC) and styrene butadiene rubber (SBR).

[0036] At least a portion of the separator 30 is interposed between the positive electrode 10 and the negative electrode 20. The separator 30 separates the positive electrode 10 and the negative electrode 20. The separator 30 may have a thickness of, for example, 10 μm to 30 μm.

[0037] The separator 30 is a porous sheet. The electrolyte permeates the separator 30. The separator 30 may have an air permeability of, for example, 200s / 100mL to 400s / 100mL. In this specification, the term "air permeability" refers to the "air resistance" defined in "JIS P 8117:2009." The air permeability is measured by the Gurley test method.

[0038] The separator 30 is electrically insulating. The separator 30 may contain, for example, a polyolefin resin. The separator 30 may be substantially made of a polyolefin resin. The polyolefin resin may contain, for example, at least one selected from the group consisting of polyethylene (PE) and polypropylene (PP). The separator 30 may have, for example, a single-layer structure. The separator 30 may be substantially made of a PE layer. The separator 30 may have, for example, a multi-layer structure. The separator 30 may be formed by laminating, for example, a PP layer, a PE layer, and a PP layer in this order. For example, a heat-resistant layer may be formed on the surface of the separator 30.

[0039] The electrolyte includes a solvent and a supporting electrolyte. The solvent is aprotic. The solvent may include any component. The solvent may include at least one selected from the group consisting of ethylene carbonate (EC), propylene carbonate (PC), butylene carbonate (BC), dimethyl carbonate (DMC), ethyl methyl carbonate (EMC), diethyl carbonate (DEC), 1,2-dimethoxyethane (DME), methyl formate (MF), methyl acetate (MA), methyl propionate (MP), and γ-butyrolactone (GBL).

[0040] The supporting electrolyte is dissolved in the solvent. The supporting electrolyte may include, for example, at least one selected from the group consisting of LiPF6, LiBF4, and LiN(FSO2)2. The supporting electrolyte may have, for example, a molar concentration of 0.5 mol / L to 2.0 mol / L. The supporting electrolyte may have, for example, a molar concentration of 0.8 mol / L to 1.2 mol / L.

[0041] The electrolyte may further contain any additive in addition to the solvent and the supporting electrolyte. For example, the electrolyte may contain 0.01% to 5% of the additive by mass fraction. The additive may include, for example, at least one selected from the group consisting of vinylene carbonate (VC), lithium difluorophosphate (LiPO2F2), lithium fluorosulfonate (FSO3Li), and lithium bis(oxalato)borate (LiBOB).

[0042] 4, the battery cell 100 further includes a detection unit 500. At least a portion of the detection unit 500 is disposed inside the exterior body 90. The detection unit 500 includes a circuit board 93 and an antenna portion 510.

[0043] As shown in Fig. 4, the circuit board 93 is located on the inner surface side of the sealing plate 91. Specifically, the circuit board 93 is attached to the inner surface of the sealing plate 91. The circuit board 93 has a circuit that detects the state of the battery cells 100. In the circuit board 93, an integrated circuit and electronic components formed on a semiconductor such as Si are mounted on a printed board having an insulating function. In this embodiment, an antenna pattern is formed on the printed board.

[0044] The state of the battery cell 100 includes at least one of the states of the voltage, the internal temperature, and the internal pressure of the battery cell 100. That is, the detection unit 500 detects the voltage of the battery cell 100, and at least one of the states of the internal temperature and the internal pressure of the battery cell 100.

[0045] The antenna unit 510 is provided on the circuit board 93. The antenna unit 510 performs wireless communication. In the present embodiment, the antenna unit 510 is disposed inside the exterior body 90. Even when the antenna unit 510 is disposed inside the exterior body 90, the antenna unit 510 can transmit and receive radio waves through the insulating members 61 and 62 disposed around the positive terminal 81 and the negative terminal 82. The antenna unit 510 may transmit and receive electromagnetic waves when performing short-range wireless communication conforming to, for example, ISO / IEC18092 or ISO / IEC14443. The antenna unit 510 may be drawn to the outside of the exterior body 90 through the injection port 41 or another hole formed in the exterior body.

[0046] In this embodiment, the short-distance wireless communication employs Bluetooth, which transmits signals contactlessly, but is not limited to Bluetooth and may employ communication based on the Near Field Communication (NFC) standard. Communication devices that comply with the NFC standard are, for example, contactless IC cards such as transportation cards and electronic money, or devices that are incorporated into small mobile devices such as mobile phones and smartphones, and transmit signals contactlessly.

[0047] The antenna unit 510 of each of the multiple battery cells 100 included in the battery pack 1 is configured to be capable of wireless communication with a wireless communication unit electrically connected to a battery management system (BMS) that is a monitoring unit arranged outside the battery cells 100. The battery management system (BMS) includes a cell management controller (CMC) and a battery management controller (BMC). The battery management system (BMS) is mounted in a battery system or on a vehicle. The battery management system (BMS) transmits and receives various signals to and from a battery ECU (Electronic Control Unit) by communication conforming to the CAN (Controller Area Network) protocol. The detection unit 500 may be connected to an available cloud through a network by bidirectional communication of the antenna unit 510.

[0048] 6 is a circuit diagram showing the electrical connection between the battery cell and the detection unit 500. As shown in FIG 6, the detection unit 500 is connected to a power supply line L1.

[0049] The power supply line L1 is connected to each of the positive current collecting member 71 and the negative current collecting member 72. However, the power supply line L1 may be connected to only one of the positive current collecting member 71 and the negative current collecting member 72. In this manner, the detection unit 500 is electrically connected to the current collecting parts and is supplied with power.

[0050] Fig. 7 is a functional block diagram showing a specific example of a detection unit. As shown in Fig. 7, the detection unit 500 includes a microcomputer 590. The microcomputer 590 is mounted on a circuit board 93. The microcomputer 590 includes a power supply control unit 591, a CPU 520, a clock control unit 592, a voltage sensor 540, an analog-to-digital converter 593, a temperature sensor 594, a peripheral function unit 595, a wireless communication function unit 596, a program memory 597, a RAM (Random access memory) 598, a non-volatile memory 599, and a program rewrite control unit 580.

[0051] The microcomputer 590 further includes two power supply terminals T1, an antenna terminal T2, and two sensor terminals T3. One of the power supply terminals T1 is electrically connected to a positive terminal 81 by a power supply line L1. The power supply line L1 connected to the positive terminal 81 is provided with a fuse 571 for overcurrent protection. The other power supply terminal T1 is electrically connected to a negative terminal 82 by the power supply line L1. A power supply input protection component 570 for overvoltage and noise protection is connected between the power supply line L1 connected to the positive terminal 81 and the power supply line L1 connected to the negative terminal 82.

[0052] Antenna terminal T2 is connected to antenna section 510. Antenna section 510 is, for example, a pattern antenna formed in a meandering shape on circuit board 93. The shape and type of antenna section 510 are set appropriately.

[0053] One of the sensor terminals T3 is connected to a pressure sensor 550. The pressure sensor 550 is disposed inside the battery cell 100 and measures the internal pressure of the battery cell 100. The other sensor terminal T3 is connected to a voltage sensor 560. The voltage sensor 560 is disposed inside the battery cell 100 and is electrically connected to the outer can 92 and measures the electric potential of the outer can 92.

[0054] The power supply control unit 591 generates operating power for the microcomputer 590 from the power supplied from the battery cell 100. The power supply control unit 591 also controls the operation mode of the microcomputer 590. Furthermore, the power supply control unit 591 can generate a reset signal.

[0055] The CPU 520 performs various controls and calculations. The clock control unit 592 generates an operation clock and a communication clock using an internal oscillator, and controls the operation clock and the communication clock.

[0056] The voltage sensor 540 detects the potential difference between one power supply terminal T1 and the other power supply terminal T1 to measure the voltage of the battery cell 100. The voltage sensor 540 converts the detected value of the potential difference, which is an analog signal, into a voltage parameter value, which is a digital signal, and outputs it.

[0057] The analog-to-digital converter 593 converts the detection values ​​of the analog signals input from the pressure sensor 550 and the voltage sensor 560 into parameter values ​​that are digital signals, and outputs the digital signals.

[0058] Temperature sensor 594 is built into microcomputer 590 and measures the internal temperature of battery cell 100. Peripheral function unit 595 manages peripheral functions of microcomputer 590 such as a timer that are necessary for program operation.

[0059] The wireless communication function unit 596 has an RF (Radio Frequency) transceiver circuit capable of transmitting and receiving. The program memory 597, which is a storage unit, is a rewritable non-volatile memory that stores programs for operating the microcomputer 590. The RAM 598 is a work memory that temporarily stores programs and data.

[0060] Non-volatile memory 599 stores data specific to battery cell 100, measurement history data, etc. Program rewrite control unit 580 rewrites or debugs the program stored in program memory 597 via wireless communication.

[0061] The microcomputer 590 is capable of detecting the state of the battery cell 100 and controlling the built-in functions based on a command signal transmitted from a wireless communication unit electrically connected to a battery management system (BMS).

[0062] The conditions of the battery cell 100 that are to be detected include the voltage of the battery cell 100 detected by the voltage sensor 540, the potential of the outer can 92 detected by the voltage sensor 560, the internal temperature of the battery cell 100 detected by the temperature sensor 594, and the internal pressure of the battery cell 100 detected by the pressure sensor 550.

[0063] The microcomputer 590 executes various processes, whereby the status information of the battery cell 100 is A / D converted and various signal processes are executed, and the information is transmitted to a battery management system (BMS). In addition, various measurement values ​​and measurement history are stored in a non-volatile memory 599.

[0064] When there is variation in the detected voltages received from the multiple battery cells 100 in the assembled battery 1, the battery management system (BMS) transmits a command signal to perform cell balancing to equalize the voltages of the battery cells 100. Specifically, a command signal is transmitted to the battery cell 100 with a higher voltage value to operate the microcomputer 590 or to communicate wirelessly. The microcomputer 590 of the battery cell 100 that received the command signal operates or communicates wirelessly, consuming power, thereby equalizing the voltages of the multiple battery cells 100 in the assembled battery 1. In this embodiment, the microcomputer 590 itself or the wireless communication function unit 596 serves as a cell balance unit that equalizes the voltages of the storage cells.

[0065] In the battery cell 100 according to this embodiment, the detection unit 500 is disposed inside the exterior body 90, thereby preventing the space occupied by the battery cell 100 equipped with the detection unit 500 that communicates wirelessly from increasing in size.

[0066] In the battery cell 100 of this embodiment, the detection unit 500 is electrically connected to the power collecting section and supplied with power, so there is no need to provide a separate power source to supply power to the detection unit 500. This makes it possible to prevent the space occupied by the battery cell 100 equipped with the detection unit 500 that communicates wirelessly from increasing in size.

[0067] By measuring the voltage of the battery cell 100 using the voltage sensor 540 connected between the positive collector 71 and the negative collector 72, the voltage of the battery cell 100 can be measured with high accuracy compared to measuring the voltage of the battery cell 100 via a bus bar connecting the battery cells 100 to each other.

[0068] By measuring the internal pressure of the battery cell 100 with the pressure sensor 550 disposed inside the battery cell 100, the internal pressure of the battery cell 100 can be measured with high accuracy.

[0069] By measuring the internal temperature of the battery cell 100 with the temperature sensor 594 arranged inside the battery cell 100, it is possible to measure the temperature at a position closer to the electrode body 50 than in conventional battery cells, and therefore it is possible to measure the internal temperature of the battery cell 100 with high accuracy. Note that the circuit board 94 may be subjected to an insulating treatment such as coating or potting with resin. This insulating treatment can prevent an internal short circuit in the battery cell 100 due to metal pieces or the like.

[0070] Modifications of the battery cell according to the present embodiment will be described below. In the following description of the modifications, the same configurations as those of the battery cell 100 according to the first embodiment will not be described repeatedly.

[0071] Fig. 8 is a partial cross-sectional view showing the periphery of an antenna portion of a battery cell according to a first modified example of embodiment 1. As shown in Fig. 8, in the battery cell according to the first modified example of embodiment 1, antenna portion 510a penetrates sealing plate 91 and extends to the outside of exterior body 90. The space between antenna portion 510a and sealing plate 91 is sealed with an insulating seal member (not shown).

[0072] According to this modified example, by arranging the circuit board 93 inside the exterior body 90 and arranging only the tip of the antenna portion 510a outside the exterior body 90, it is possible to improve the wireless communication characteristics of the detection unit 500A while preventing the space occupied by the battery cell from increasing in size.

[0073] Fig. 9 is an exploded perspective view showing the configuration of a battery cell detection unit and an exterior body according to a second modified example of embodiment 1. Fig. 10 is a partial cross-sectional view showing the configuration of a battery cell detection unit according to a first modified example of embodiment 1.

[0074] 9 and 10, in a battery cell according to a second modified example of the first embodiment, a detection unit 500B includes an insulating circuit board 93B having a circuit for detecting the state of the battery cell, and an antenna section 510 provided on the insulating circuit board 93B. The insulating circuit board 93B seals the opening of the exterior can 92. The antenna section 510 is located outside the exterior body.

[0075] Insulating circuit board 93B is made of insulating resin such as glass epoxy resin. In this modification, positive electrode terminal 81 and negative electrode terminal 82 are directly fixed to a sealing plate made of insulating circuit board 93B. Insulating circuit board 93B and exterior can 92 are airtightly joined to each other with a bonding material (not shown).

[0076] According to this modification, by arranging the insulating circuit board 93B inside the exterior body and arranging the antenna part 510 outside the exterior body, it is possible to improve the wireless communication characteristics of the detection unit 500B while suppressing an increase in the space occupied by the battery cell. Furthermore, the insulating members 61 and 62 are not necessary, and the number of parts can be reduced.

[0077] (Embodiment 2) A battery cell according to embodiment 2 will be described below with reference to the drawings. The battery cell according to embodiment 2 differs from battery cell 100 according to embodiment 1 in that the exterior body is a pouch type and the electrode body, which is the main body, is a laminated type, and therefore description of the same configuration as battery cell 100 according to embodiment 1 will not be repeated.

[0078] Fig. 11 is a plan view showing the appearance of a battery cell according to embodiment 2. Fig. 12 is an exploded perspective view showing the configuration of a battery cell according to embodiment 2. As shown in Figs. 11 and 12, a battery cell 100A according to embodiment 2 includes an exterior body 600, an electrode body 50A, and a detection unit 500.

[0079] The exterior body 600 is formed by bonding two sheets of shrink film together. The shrink film is, for example, an aluminum laminate film formed by laminating an aluminum foil and a resin film. The electrode body 50A is disposed inside the exterior body 600. The inside of the exterior body 600 is filled with an electrolyte (not shown).

[0080] The electrode body 50A is configured by laminating, in this order, a positive electrode 700, a separator 900, and a negative electrode 800. A positive electrode current collector 710, which is a part of the positive electrode 700, and a negative electrode current collector 810, which is a part of the negative electrode 800, are each extended to the outside of the exterior body 600.

[0081] At least a portion of the separator 900 is interposed between the positive electrode 700 and the negative electrode 800. The separator 900 separates the positive electrode 700 and the negative electrode 800. The separator 900 is a porous sheet. The electrolyte permeates the separator 900. The separator 900 is electrically insulating.

[0082] The detection unit 500 is disposed on the negative electrode 800 inside the exterior body 600. The detection unit 500 is electrically connected to the negative electrode 800 and is supplied with power. In order to enable wireless communication of the antenna unit, an opening may be provided in the aluminum foil located in the exterior body 600 at a portion covering the antenna unit, or only the tip of the antenna unit may be located outside the exterior body 600. The antenna unit may be drawn to the outside of the exterior body 600 through a hole formed in the exterior body 600.

[0083] In the battery cell 100A according to this embodiment, the detection unit 500 is disposed inside the exterior body 600, which makes it possible to prevent an increase in the space occupied by the battery cell 100A that includes the detection unit 500 that wirelessly communicates. Furthermore, since the pouch-type exterior body 600 is smaller than an exterior body having an exterior can, an increase in the space occupied by the battery cell 100A can be effectively prevented.

[0084] Modifications of the battery cell according to the present embodiment will be described below. In the following description of the modifications, the same configuration as that of the battery cell 100A according to the second embodiment will not be described repeatedly.

[0085] Fig. 13 is a plan view showing the appearance of a battery cell according to a modification of embodiment 2. As shown in Fig. 13, the detection unit 500 of the battery cell 100B according to the modification of embodiment 2 is disposed on the negative electrode current collector 810. The detection unit 500 is electrically connected to the negative electrode current collector 810 and receives power.

[0086] In the battery cell 100B according to this modification, the detection unit 500 is electrically connected to the power collecting section and is supplied with power, so there is no need to provide a separate power source to supply power to the detection unit 500, and this makes it possible to prevent the space occupied by the battery cell 100B including the detection unit 500 that communicates wirelessly from becoming large. By arranging the antenna section outside the exterior body 600, the wireless communication characteristics of the detection unit 500 can be improved.

[0087] Although the embodiment of the present technology has been described above, the embodiment disclosed herein should be considered as illustrative and not restrictive in all respects. The scope of the present technology is defined by the claims, and it is intended to include all modifications within the scope and meaning equivalent to the claims. [Explanation of symbols]

[0088] 1 battery pack, 10,700 positive electrode, 11 positive electrode substrate, 12 positive electrode active material layer, 20,800 negative electrode, 21 negative electrode substrate, 22 negative electrode active material layer, 30,900 separator, 41 inlet, 42 gas exhaust valve, 50,50A electrode body, 61,62 insulating member, 71 positive electrode current collector, 72 negative electrode current collector, 81 positive electrode terminal, 82 negative electrode terminal, 90,600 exterior body, 91 sealing plate, 92 exterior can, 93 circuit board, 93B insulating circuit board, 100,100A,100B battery cell, 200 end plate, 210 step portion, 300 restraining member, 310 first member, 320 second member, 400 resin plate, 500,500A,500B Detection unit, 510, 510a antenna section, 540, 560 voltage sensor, 550 pressure sensor, 570 power input protection component, 571 fuse, 580 program rewrite control section, 590 microcomputer, 591 power supply control section, 592 clock control section, 593 analog-to-digital converter, 594 temperature sensor, 595 peripheral function section, 596 wireless communication function section, 597 program memory, 598 RAM, 599 non-volatile memory, 710 positive electrode current collecting section, 810 negative electrode current collecting section, L1 power supply line, T1 power supply terminal, T2 antenna terminal, T3 sensor terminal.

Claims

1. A storage cell for use in a battery pack including a plurality of storage cells, the battery management system being configured to transmit a command signal for performing cell balancing to equalize the voltages of the storage cells, An exterior body; A main body portion disposed inside the exterior body; a detection unit that is at least partially disposed inside the exterior body, detects a state of the power storage cell, and wirelessly communicates with the power storage cell; the detection unit includes a cell balance unit that equalizes the voltages of the storage cells, the cell balance unit operates using power from the power storage cell, The detection unit includes a microcomputer. The microcomputer includes a wireless communication function unit, A storage cell in which the microcontroller (excluding the wireless communication function unit) becomes the cell balance unit, and the voltages of the storage cells are equalized by consuming power as the microcontroller operates (excluding the microcontroller operating in order for the wireless communication function unit to communicate wirelessly).

2. Further comprising a current collecting portion connected to the main body portion, The storage cell according to claim 1 , wherein the detection unit is electrically connected to the current collecting portion to receive power therefrom.

3. the detection unit includes a substrate having a circuit for detecting a state of the power storage cell, and an antenna portion provided on the substrate; the exterior body includes an exterior can having an opening and a sealing plate that seals the opening of the exterior can, the substrate is located on the inner surface side of the sealing plate, The energy storage cell according to claim 1 , wherein the antenna portion extends to the outside of the exterior body by penetrating the sealing plate or the exterior body.

4. the detection unit includes an insulating substrate having a circuit for detecting a state of the power storage cell, and an antenna portion provided on the insulating substrate; The exterior body includes an exterior can having an opening, the insulating substrate seals the opening of the exterior can, The energy storage cell according to claim 1 or 2, wherein the antenna portion is located outside the exterior body.

5. The storage cell according to claim 1 or 4, wherein the detection unit detects at least one of a voltage of the storage cell, an internal temperature of the storage cell, and an internal pressure of the storage cell.

6. The detection unit includes a memory unit, The storage cell according to claim 5 , wherein the storage unit stores data obtained by detecting a state of the storage cell.

7. The storage cell according to claim 5 , wherein the microcomputer further includes a power supply terminal, an antenna terminal, and a sensor terminal.

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