Battery pack, power supply device having the battery pack, electric vehicle having the power supply device, and power storage device

Abstract

The battery assembly includes: a battery stack (2) formed by stacking a plurality of battery cells (1); a pair of end plates (3) arranged at both ends of the battery stack (2) in the stacking direction; a tightening strip (4) connecting the pair of end plates (3); and an electronic circuit block (6) formed by installing a voltage detection circuit (22) for detecting the voltage of the battery cell (1), wherein the electronic circuit block (6) is arranged on the outer surfaces of two end plates (3) arranged at both ends of the battery stack (2), and each electronic circuit block (6) is connected to the battery cell (1) by means of a voltage detection line (19).

Description

Technical Field

[0001] The present invention relates to a battery assembly formed by connecting a plurality of battery cells, a power supply device composed of a plurality of battery assemblies, an electric vehicle and a power storage device having the power supply device, and in particular to a battery assembly and a power supply device for supplying electric power to an electric motor installed in an electric vehicle such as a hybrid vehicle, an electric vehicle, a fuel cell vehicle, an electric motorcycle, etc. to drive the vehicle, or a battery assembly and a power supply device for large currents used for power storage purposes such as household and factory use, and an electric vehicle and a power storage device having the power supply device.

[0002] In this specification, the term "battery assembly" is used in a broad sense, including a complete battery assembly that includes end plates arranged at both end faces of a plurality of battery cells, a pair of end plates connected by tightening strips, and a voltage detection circuit for detecting the voltage of the battery cells, for example, a "battery pack" that does not have a built-in control circuit such as a charge and discharge control circuit for regulating the charge and discharge current. Background Art

[0003] A battery module including a plurality of battery cells is used as a power source for vehicles such as hybrid vehicles and electric vehicles, and as a power source for power storage systems for factories and homes (see, for example, Patent Document 1).

[0004] An example of such a battery module is shown in Fig.15 Exploded perspective view. In the battery assembly 900 shown in the figure, a plurality of battery cells 901 are stacked to form a battery stack 902, end plates 903 are arranged on both end surfaces of the battery stack 902, and a pair of end plates 903 are fastened by tightening bars 904 to fix the battery cells 901. In each battery cell 901, a pair of positive and negative electrode terminals 911 are arranged on the terminal surface 910 of the upper surface. The positive and negative electrode terminals 911 are electrically connected by means of bus bars 914, and the battery cells 901 are connected in series and in parallel.

[0005] Furthermore, a circuit board 906 connected to each battery cell 901 is disposed on the upper surface of the battery stack 902. The circuit board 906 is mounted with a voltage detection circuit for detecting information such as the voltage of the battery cell 901 so that the battery cell 901 can be charged and discharged while being protected.

[0006] Prior art literature

[0007] Patent Literature

[0008] Patent Document 1: International Publication No. 2014 / 024452 Summary of the invention

[0009] Problem that the invention aims to solve

[0010] In the above battery assembly, the circuit substrate becomes an obstacle that causes the overall height to increase. In addition, a gas channel is also arranged on the upper surface of the battery stack, but since the gas channel is used for the high-temperature, high-pressure gas ejected from the exhaust valve of the battery cell to flow in, the high-temperature, high-pressure exhaust gas leaking from the gas channel becomes the cause of the circuit substrate failure.

[0011] The present invention is developed for the purpose of preventing the above disadvantages. The purpose of the present invention is to provide a technology that reduces the height of the battery module while preventing the high-temperature, high-pressure exhaust gas ejected from the battery cells from damaging the circuit substrate and achieving higher safety.

[0012] Solutions for solving problems

[0013] A battery assembly of one embodiment of the present invention includes: a battery stack formed by stacking a plurality of battery cells; a pair of end plates arranged at both ends of the battery stack in the stacking direction; a tightening strip connecting the pair of end plates; and an electronic circuit block formed by installing a voltage detection circuit for detecting the voltage of the battery cells, wherein the electronic circuit blocks are arranged on the outer surfaces of two end plates arranged at both ends of the battery stack, and each electronic circuit block is connected to the battery cells by means of a voltage detection line.

[0014] A power supply device according to one embodiment of the present invention is a power supply device having a plurality of the above-mentioned battery assemblies, wherein the power supply device includes a power line and an external communication line connecting adjacent battery assemblies, connecting the power line to the output terminal of the battery assembly, connecting the external communication line to the communication terminal, connecting the external communication line to the communication terminal located at the end of the battery assembly connected to the power line, and connecting both the power line and the external communication line to the ends on the same side of the battery assembly.

[0015] An electric vehicle according to one embodiment of the present invention includes: the power supply device described above; a motor for traveling, which is supplied with electric power from the power supply device; a vehicle body, which carries the power supply device and the motor; and wheels, which are driven by the motor to cause the vehicle body to travel.

[0016] A power storage device according to one embodiment of the present invention includes: the power supply device described above; and a power supply controller that controls charging and discharging of the power supply device, wherein the power supply controller controls so that a battery cell can be charged with power from an external source, and the battery cell is charged.

[0017] Effects of the Invention

[0018] The above battery module can protect the electronic circuit block having a voltage detection circuit from the influence of high-temperature and high-pressure exhaust gas while reducing the height, thereby achieving high safety and being able to efficiently dissipate heat from the electronic circuit block. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a perspective view of a battery pack according to Embodiment 1 of the present invention.

[0020] Figure 2 yes Figure 1 An exploded perspective view of the battery assembly is shown.

[0021] Figure 3 yes Figure 1 A cross-sectional view of the battery assembly taken along line III-III is shown.

[0022] Figure 4 This is a schematic perspective view of a battery module according to Embodiment 1 of the present invention.

[0023] Figure 5 This is a circuit diagram showing an example of an electronic circuit block.

[0024] Figure 6 It is a schematic perspective view of a battery module of a reference example.

[0025] Figure 7 Yes means Figure 1 A top view of the end of a battery assembly is shown.

[0026] Figure 8 yes Figure 7 A cross-sectional view of the battery assembly taken along line VIII-VIII is shown.

[0027] Fig. 9 This is an enlarged plan view showing another example of the connection structure between the end plate and the electronic circuit block.

[0028] Fig.10 This is a schematic top view of a power supply device including a plurality of battery modules.

[0029] Fig.11 yes Fig.10 The schematic circuit diagram of the power supply device shown.

[0030] Fig.12 This is a block diagram showing an example in which a battery pack is mounted on a hybrid vehicle that runs using an engine and an electric motor.

[0031] Fig.13 This is a block diagram showing an example in which a battery pack is mounted on an electric vehicle that runs only with an electric motor.

[0032] Fig.14 This is a block diagram showing an example in which a battery pack is used in a power storage device.

[0033] Fig.15 This is an exploded perspective view of a conventional battery assembly. DETAILED DESCRIPTION

[0034] First, a focus of the present invention is explained. In a conventional power supply assembly, a gas channel is arranged on the upper surface of the battery stack in order to discharge the exhaust gas ejected from the exhaust valve of the battery cell to the outside. The gas channel is provided to discharge the high-temperature, high-pressure exhaust gas ejected from the exhaust valve of the battery cell to the outside. The exhaust valve of the battery cell opens when the internal pressure rises to a set value to prevent the battery shell from rupturing. The exhaust valve detects the abnormal increase in the internal pressure of the battery and opens the valve, but due to overcharging, overdischarging, and internal short circuits, combustion occurs inside the battery cell, and the internal pressure of the battery cell increases abnormally, so the exhaust gas becomes high temperature and high pressure. The high-temperature, high-pressure exhaust gas ejected from the battery cell causes adverse effects such as burning surrounding components, so it is discharged to the outside through the gas channel. The gas channel is arranged on the battery stack in order to guide the exhaust gas from the exhaust valve of the battery cell to the outside. The gas channel is provided with an inflow hole for the exhaust gas ejected from the exhaust valve of each battery cell to flow into the inside.

[0035] Furthermore, the power supply assembly includes a circuit substrate on which a voltage detection circuit for detecting the voltage of a battery cell is installed to prevent overcharging and overdischarging of each battery cell. The voltage detection circuit provided on the circuit substrate is connected to the electrode terminal of the battery cell via a voltage detection line to detect the voltage of each battery cell. The circuit substrate is arranged on the upper surface of the battery stack, and the voltage detection line can be shortened. The impedance of the short voltage detection line is small, and the cell voltage can be accurately detected.

[0036] As described above, in a power supply assembly including a gas channel and a circuit substrate, the gas channel is arranged on the electrode surface of the battery stack and connected to the exhaust valve of the battery cell, and the circuit substrate is arranged on the gas channel. The voltage detection circuit of the circuit substrate can be connected to the battery cell by means of a voltage detection line.

[0037] Here, in the power supply assembly, a gas channel extending along the stacking direction of the battery cells is arranged on the upper surface of the battery stack, so that the exhaust gas ejected from the battery cells can be smoothly discharged to the outside, and a circuit substrate extending along the stacking direction of the battery cells is arranged on the gas channel, so that the voltage detection circuit of the circuit substrate can be connected to the electrode terminals of the battery cells using a shorter voltage detection line. However, in the power supply assembly of this structure, the high-temperature and high-pressure exhaust gas ejected from the battery cells causes adverse effects such as burning the circuit substrate. In particular, the electronic components of the voltage detection circuit of the circuit substrate are adversely affected by the high-temperature and high-pressure exhaust gas, and the safety is reduced. In addition, connectors and leads of the voltage detection line are also arranged on the upper surface of the battery stack, but the high-temperature and high-pressure exhaust gas burns the connectors and leads, and the heat of these combustions causes the battery cells to smoke and catch fire in a chain reaction, which becomes a cause of reduced safety.

[0038] Since the exhaust gas is abnormally high in temperature and high in pressure, it is difficult for the gas channel to completely exhaust the gas to the outside. The circuit substrate is separated from the terminal surface of the battery cell due to the gas channel, but the exhaust gas leaking from the gas channel may cause the circuit substrate to burn and further increase thermal damage. In addition, the exhaust gas contains foreign matter such as metal pieces inside the battery cell, which may also cause short circuit failures in the electronic circuit of the circuit substrate.

[0039] Moreover, the battery assembly is almost without exception required to be miniaturized in all uses. The purpose is to increase the capacity of charge and discharge relative to the unit volume and achieve high performance. However, a plurality of components are arranged on the upper surface of the battery stack, so it is difficult to make the whole lower. Specifically, as a component arranged on the upper surface of the battery stack, it includes a gas channel for discharging exhaust gas, an electrode terminal protruding from the terminal surface, a bus bar of a metal plate for connecting adjacent electrode terminals to each other, a circuit substrate for mounting electronic components, a lead connecting the circuit substrate and the battery cell, and an insulating material for insulating the components from the high-voltage battery stack. Most of these components need to be arranged in a non-interfering manner.

[0040] For a battery assembly in which multiple components such as a gas channel, a circuit substrate, and a lead are arranged on the upper surface of a battery stack, it is difficult to reduce the height of the battery assembly and achieve miniaturization only by improving the component arrangement, and the circuit substrate actually becomes a disadvantage of increasing the volume of the battery assembly, especially increasing the height. On the other hand, if the circuit substrate is made thinner and miniaturized, the disadvantage of not being able to efficiently dissipate the heat energy of the heat-generating components mounted on the circuit substrate becomes significant. Since heat-generating components such as semiconductor elements and discharge resistors are mounted on the circuit substrate, it is extremely important to efficiently dissipate heat energy so that the temperature rise of the heat-generating components is lower than the set temperature. The power supply assembly described in the following embodiments can eliminate the above disadvantages by utilizing a unique structure.

[0041] The present invention is described in detail below based on the accompanying drawings. In addition, in the following description, terms indicating specific directions and positions (for example, "upper", "lower" and other terms including these terms) are used as needed, but the purpose of using these terms is to facilitate understanding of the invention with reference to the accompanying drawings, and the protection scope of the present invention is not limited to the meaning of these terms. In addition, the parts with the same reference numerals shown in multiple drawings represent the same or equivalent parts or components.

[0042] Moreover, the embodiments shown below represent specific examples of the technical ideas of the present invention, and the present invention is not limited to the following embodiments. In addition, as for the size, material, shape, relative configuration, etc. of the components described below, as long as there is no specific description, it is not intended to limit the scope of the present invention to only this, but to illustrate. In addition, the content described in one embodiment and the embodiment can also be applied to other embodiments and embodiments. In addition, the size, positional relationship, etc. of the components shown in the drawings are sometimes exaggerated in order to make the description clear.

[0043] The battery assembly of the first embodiment of the present invention includes: a battery stack formed by stacking a plurality of battery cells; a pair of end plates disposed at both ends of the battery stack in the stacking direction; a tie bar connecting the pair of end plates; and an electronic circuit block formed by installing a voltage detection circuit for detecting the voltage of the battery cell. The electronic circuit blocks are arranged on the outer surfaces of the two end plates disposed at both ends of the battery stack, and each electronic circuit block is connected to the battery cell via a voltage detection line.

[0044] The above battery assembly has the following advantages: while protecting the circuit substrate from the high-temperature, high-pressure exhaust gas ejected from the exhaust valve of the battery cell, the battery assembly can be miniaturized and the charge and discharge capacity relative to the unit volume can be increased. Moreover, the heat energy of the electronic circuit block installed with the voltage detection circuit can be efficiently dissipated to the end plate and the outside, which can reduce the temperature rise of the electronic circuit block. In particular, the above structure has the following advantages: the electronic circuit block can be arranged on the surface of the end plate in a vertical posture, so that the air can convect smoothly on the surface of the electronic circuit block and dissipate heat efficiently. In addition, for the electronic circuit block that is isolated from the high-temperature, high-pressure exhaust gas by the end plate, even in the abnormal use state of the battery cell with the exhaust valve open, it can be in a normal working state and ensure higher safety. The characteristic of being able to efficiently dissipate the heat energy of the electronic circuit block also achieves the advantage of being able to reduce the temperature rise while miniaturizing the electronic circuit block. It also achieves the advantage that the temperature rise of the electronic components installed in the electronic circuit block is also reduced, which can ensure the stable operation of the electronic components.

[0045] Moreover, in the above battery assembly, electronic circuit blocks are arranged on two end plates arranged at both ends of the battery stack, that is, the electronic circuit blocks are divided into two groups and arranged on the end plates, so that the voltage detection line connecting the battery cell and the electronic circuit block can be shortened. The reason is that each battery cell can be connected to the electronic circuit block arranged nearby by using the voltage detection line. Being able to shorten the voltage detection line is extremely important for detecting the voltage of the battery cell with higher accuracy. The reason is that the impedance of a longer voltage detection line becomes higher and is easily affected by noise, and then the voltage drop also becomes larger, and the noise and voltage drop become the cause of the detection error of the single cell voltage. The detection accuracy of the single cell voltage affects the deterioration and life of the battery assembly, so it is extremely important to be able to detect it with high accuracy.

[0046] In the above battery assembly, the electronic circuit block is not arranged on the electrode surface of the battery stack but on the outer surface of the end plate, so the overall design can be lower, and the electronic circuit block can be protected from the high temperature and high pressure exhaust gas ejected from the battery cell. In addition, since the end plate is arranged between the battery stack and the electronic circuit block, the end plate isolates the electronic circuit block from the exhaust gas of the battery cell, and can protect the electronic circuit block from the exhaust gas of the high temperature and high pressure, so that even in an abnormal state, the normal operation of the electronic circuit block can be guaranteed to ensure higher safety. In addition, the following advantages are also achieved: the electronic circuit block is set as two groups and arranged at the end plates at both ends of the battery stack, so the voltage detection line connecting the battery cell and the electronic circuit block is shortened to reduce the impedance of the line, especially the resistance is reduced to detect the voltage of each battery cell with high precision. In addition, the heat generated by the electronic circuit block can be efficiently dissipated to the end plate, so the temperature rise of the electronic circuit block can be reduced. In addition, the electronic circuit block can be arranged on the surface of the end plate in a vertical posture, so that air can be convected smoothly on the surface of the electronic circuit block to improve the cooling efficiency. For the structure that can efficiently dissipate heat from the electronic circuit block, even if the electronic circuit block is miniaturized and the heat is concentrated in a narrow area, the temperature rise can be locally reduced, and the temperature rise of the electronic components of the electronic circuit block can be reduced, and more stable operation can be ensured.

[0047] In the battery module of the second embodiment of the present invention, a battery stack composed of a plurality of battery cells is divided into a plurality of battery units in the middle of the stacking direction of the battery cells, and each battery unit is connected to each electronic circuit block via a voltage detection line.

[0048] In the battery assembly of the third embodiment of the present invention, the battery stack includes a gas channel connected to the opening of the exhaust valve provided in the battery cell, the gas channel is arranged in the central part of the electrode surface of the battery stack in a posture extending along the stacking direction of the battery cell, and the voltage detection line is arranged along the side edge of the gas channel.

[0049] The above battery assembly has the following advantages: it is possible to reduce the wiring space of the voltage detection line, thereby expanding the lateral width of the gas channel arranged on the electrode surface, and smoothly discharge the exhaust gas to prevent gas leakage. The reason why gas leakage can be prevented and safety can be ensured is that the internal pressure rise of the gas channel is reduced. The reason why the wiring space of the voltage detection line can be reduced is that the voltage detection line is branched into two groups of electronic circuit blocks, and the number of voltage detection lines connected to each electronic circuit block can be reduced.

[0050] In the battery module according to the fourth embodiment of the present invention, the voltage detection lines are arranged on both sides of the gas channel.

[0051] The above battery module has the advantage that the voltage detection lines connected to the respective electronic circuit blocks can be separately arranged on both sides of the gas channel, so that the wiring space on both sides of the gas channel can be further reduced.

[0052] In the battery pack according to the fifth embodiment of the present invention, the electronic circuit block includes a cell balance adjustment circuit for adjusting the cell balance of each battery cell, and the cell balance adjustment circuit adjusts the cell balance of each battery cell by energizing the voltage detection line.

[0053] The above battery assembly has the following advantages: by using the voltage detection line for adjusting the cell balance, each battery cell can be quickly balanced. The reason is that by connecting the voltage detection line for cell balancing to a relatively close electronic circuit block, the voltage detection line can be shortened and the resistance can be reduced. By shortening the voltage detection line and reducing the resistance, the voltage drop of the wiring is reduced during cell balancing, and the voltage detection accuracy is improved.

[0054] In the battery pack according to the sixth embodiment of the present invention, the voltage detection line is provided as a wiring harness or a printed circuit board.

[0055] In the battery pack according to the seventh embodiment of the present invention, the printed circuit board of the voltage detection line is a flexible printed circuit board (FPC).

[0056] The above battery pack has the advantage that the voltage detection line can be divided into two and connected to an electronic circuit block arranged nearby, so that the voltage detection line can be shortened, and the flexible printed circuit board can be shortened and mass-produced at low cost.

[0057] In the battery pack of the eighth embodiment of the present invention, the electronic circuit block includes a communication terminal capable of transmitting signals by cascading a plurality of electronic circuit blocks, and the communication terminal is internally connected via a coupling element that blocks direct current and passes alternating current signals.

[0058] The above battery assembly has the following advantages: the communication terminal is connected internally by means of a coupling element, so it can be connected to other communication terminals and transmit signals without adjusting to a DC level. This is particularly effective in a device in which multiple battery assemblies are connected in series. In a device in which multiple battery assemblies are connected in series, a potential difference is generated in the ground wire of each battery assembly. The communication terminal of the electronic circuit block uses the ground wire as a reference potential to transmit signals, so a bias voltage needs to be applied to the communication terminal with a potential difference in the ground wire to change the DC level of the ground wire and set the potential difference of the ground wire of the connected communication terminal to zero level, but the circuit structure is quite complicated. In particular, in a device in which multiple battery assemblies are connected in series, the ground wire changes in a step-like manner, so using multiple bias voltages to make the ground wire equal leads to an extremely complex circuit structure. Moreover, the bias voltage that makes the ground wire equal varies according to the temperature, so it is necessary to control the temperature characteristics extremely accurately, and the circuit structure becomes complicated. The above battery assembly has the following advantages: there is no need to use a bias voltage to balance the DC level of the ground wire, and multiple battery assemblies can be connected in series and the communication terminals of the battery assemblies with a potential difference in the ground wire can be simply connected to transmit signals.

[0059] In the battery pack according to the ninth aspect of the present invention, the coupling element is any one of a coupling capacitor, a transformer, and a photoelectric transmission element.

[0060] The power supply device of the 10th embodiment of the present invention is a power supply device having a plurality of the above-mentioned battery assemblies, wherein adjacent battery assemblies are connected by a power line and an external communication line, the power line is connected to the output terminal of the battery assembly, the external communication line is connected to the communication terminal, the external communication line is connected to the communication terminal located at the end of the battery assembly connected to the power line, and both the power line and the external communication line are connected to the ends on the same side of the battery assembly.

[0061] In the power supply device according to the eleventh embodiment of the present invention, the battery modules disposed adjacent to each other are connected to the external communication line at a pair of communication terminals disposed closest to each other.

[0062] (Implementation Method 1)

[0063] The battery packs shown in the following embodiments are mainly most suitable as power sources for electric vehicles such as hybrid vehicles that use both an engine and an electric motor, plug-in hybrid vehicles, electric vehicles that use only an electric motor, and electric motorcycles that use an electric motor to drive. However, the battery pack of the present invention is also suitable as a power source for power storage devices for applications other than electric vehicles that require high output.

[0064] Figure 1 to Figure 4 The battery assembly 10 shown includes: a battery stack 2, which is formed by stacking a plurality of battery cells 1 in the thickness direction; a pair of end plates 3, which are arranged at both ends of the battery stack 2 in the stacking direction of the battery cells 1; a tightening bar 4, which connects the end plates 3 at both ends of the battery stack 2; and an electronic circuit block 6, which is formed by installing a voltage detection circuit for detecting the voltage of the battery cells 1 of the battery stack 2. In addition, the battery assembly 10 shown in the figure includes: a gas channel 5, which is connected to the opening of the exhaust valve 1a provided in each battery cell 1; a cover 8, which is arranged above the battery stack 2 and above the gas channel 5; and a bottom plate 9, which is arranged below the battery stack and fixes the end plates 3.

[0065] (Battery cell 1)

[0066] like Figure 2 As shown, the battery cell 1 is a square secondary battery with a width larger than thickness, in other words, a thickness smaller than width, and is stacked in the thickness direction to form a battery stack 2. The battery cell 1 is a lithium-ion secondary battery. However, the battery cell can also be set as any other rechargeable secondary battery such as a nickel-hydrogen battery, a nickel-cadmium battery, etc. In the battery cell 1, the positive and negative electrode plates and the electrolyte are stored together in an outer can with a sealed structure. For the outer can, a metal plate such as aluminum or an aluminum alloy is pressed into a square shape, and the opening is sealed airtightly with a sealing plate. The sealing plate is the same aluminum or aluminum alloy as the outer can, and the positive and negative electrode terminals 11 are fixed, and an exhaust valve is provided between the electrode terminals 11. In addition, the positive and negative electrode terminals 11 are set in a state where at least one electrode terminal 11 is insulated from the sealing plate. In the battery cell 1, the sealing plate is used as the terminal surface 1X and the positive and negative electrode terminals 11 are provided. Moreover, in the battery cell 1, the bottom and side surfaces of the outer can are covered with an insulating film.

[0067] Multiple battery cells 1 are stacked in a stacking direction with their thicknesses forming a battery stack 2. Multiple battery cells 1 are stacked in a stacking direction with their terminal surfaces 1X having positive and negative electrode terminals 11 arranged on the same plane to form electrode surfaces 2X.

[0068] (Battery stack 2)

[0069] In the battery stack 2, as Figure 2As shown, an insulating spacer 12 is sandwiched between the stacked battery cells 1. The insulating spacer 12 in the figure is made of an insulating material such as resin and is formed into a thin plate or sheet. The insulating spacer 12 shown in the figure is set to a plate shape that is roughly equal in size to the opposite surface of the battery cell 1. The insulating spacer 12 is stacked between the battery cells 1 adjacent to each other to insulate the adjacent battery cells 1 from each other. In addition, as a spacer arranged between adjacent battery cells 1, a spacer of a shape that forms a flow path for cooling gas between the battery cell and the spacer can also be used.

[0070] In the battery stack 2, a metal bus bar 14 is connected to the positive and negative electrode terminals 11 of adjacent battery cells 1, and the bus bar 14 is used to connect multiple battery cells 1 in series or in parallel or in series and in parallel. In the battery stack 2, the output voltage and the charge and discharge capacity are set to set values ​​by the number of stacked battery cells 1. In the battery stack 2, the output voltage can be increased by the number of battery cells 1 connected in series, and the charge and discharge capacity can be increased by the number of battery cells 1. For the battery assembly 10, the output voltage and capacity are set to set values ​​by the number of battery cells 1 constituting the battery stack 2 and their connection states of parallel and series connection, so the number and connection state of the battery cells 1 are set to the optimal state in consideration of the purpose.

[0071] The busbar 14 is provided with a connection portion (not shown) for connecting to the electrode terminal 11. The busbar 14 is connected to the electrode terminal 11 by welding by irradiating a laser beam to the boundary connecting the connection portion and the electrode terminal 11. However, for the busbar, it is possible to connect to the electrode terminal by providing an external thread on the electrode terminal, opening a through hole for the electrode terminal to pass through, and screwing a nut into the external thread of the electrode terminal passing through the through hole, or it is possible to connect to the electrode terminal by providing an internal thread hole on the electrode terminal and screwing a stop screw passing through the busbar into the internal thread hole. In the battery assembly 10, a resin insulating cover (not shown) can be provided on the upper surface of the battery stack 2. For the insulating cover, it is possible to provide an opening portion so that the electrode terminal 11 is exposed from the opening portion, and on the upper surface side of the insulating cover, the busbar 14 of the metal plate is connected to the electrode terminal 11 exposed from the opening portion of the insulating cover, so that a plurality of battery cells 1 are connected in a predetermined arrangement.

[0072] (End surface spacer 13)

[0073] In the battery stack 2, in order to insulate the end plates 3 made of metal, the end plates 3 can be arranged at both end faces with end face spacers 13 between them. The end face spacers 13 are arranged between the battery stack 2 and the end plates 3 to insulate the end plates 3 from the battery stack 2. The end face spacers 13 are made of insulating materials such as resin and are formed into a relatively thin plate or sheet. The end face spacers 13 are provided with a plate portion of a size that can cover the entire opposite surface of the battery cell 1, and the plate portion is stacked between the battery cells 1 and the end plates 3 arranged at the two ends of the battery stack 2.

[0074] (End plate 3)

[0075] The end plates 3 are located at the two end surfaces of the battery stack 2 in the stacking direction of the battery cells 1 and fix the battery stack 2. The end plates 3 are metal plates, and are rectangular plates with an outer shape that is roughly equal to the outer shape of the battery cell 1 or slightly larger than the battery cell 1. The end plates 3 can be made of high-tensile steel into a strong structure. The end plates 3 can be set as a single metal plate or a structure of stacking multiple metal plates, or as a stack of metal plates and plastics. The end plate 3 composed of a single metal plate has a large specific heat capacity and can efficiently absorb the thermal energy of the electronic circuit block 6. In addition, for the end plate 3 with multiple stacked plates, at least the surface side on which the electronic circuit block 6 is fixed is set to a metal plate. The purpose is to fix the electronic circuit block 6 in a thermally coupled state to improve the heat dissipation characteristics. In addition, the end plate 3 can be set as a stacked structure of an aluminum plate and a high-tensile steel plate. The end plate can also be configured as follows: the surface side is an aluminum plate to fix the electronic circuit block, and the aluminum plate and the high-tensile steel plate are stacked in a surface contact state, so that heat can be efficiently transferred from the aluminum plate to the high-tensile steel plate. However, the end plate does not necessarily have to be made of metal, and can also be made of plastic with excellent strength, such as engineering plastic.

[0076] (Tightening strip 4)

[0077] The tie bars 4 extend along the stacking direction of the battery cells 1 and have both ends fixed to the end plates 3 , so that the battery stack 2 is fixed by the pair of end plates 3 . Figure 1 and Figure 2 The tie bar 4 shown is a metal plate having a predetermined upper and lower width and a predetermined thickness along the side of the battery stack 2, and is arranged opposite to the two side surfaces of the battery stack 2. The tie bar 4 applies a strong pressure to the two end surfaces of the battery stack 2, and arranges the battery cell 1 that is to be expanded by charging and discharging in a fixed position. The metal plate of the tie bar 4 is preferably made of high-tensile steel. The tie bar 4 of the metal plate is formed into a predetermined shape by press forming.

[0078] For the tightening strip 4, if Figure 2As shown in the exploded perspective view of FIG, in order to fix the two ends to a pair of end plates 3, at both ends of the battery stack 2 in the stacking direction, the two ends are bent along the outer side surfaces of the end plates 3 to provide fixing portions 4A. The tightening strip 4 fastens the pair of end plates 3 by screwing the fixing portions 4A to the end plates 3, etc.

[0079] Moreover, for the tightening strip 4, if Figure 2 and Figure 3 As shown, the lower end is bent into an L shape to form a lower connecting piece 4B. The lower connecting piece 4B is stacked on the lower surface side of the two side portions of the bottom plate 9 and connected to the bottom plate 9. Moreover, for the tightening strip 4, the upper end is bent to form a pressing piece 4C that presses the end of the upper surface of the battery stack 2. The pressing piece 4C is separated for each battery cell 1 so as to be able to press the upper surface of the battery cell 1 of the battery stack 2 individually. Thus, each pressing piece 4C can press the battery cell 1 toward the bottom plate 9 side independently of the adjacent pressing piece 4C. In this way, each battery cell 1 can be prevented from floating from the bottom plate 9 and maintained in the height direction, and even if vibration, impact, etc. are applied to the battery stack 2, each battery cell 1 can be maintained in the upper and lower directions. In this way, the tightening strip 4 covers and holds the corners of the upper and lower surfaces of the battery stack 2 at the left and right side portions of the battery stack 2.

[0080] In addition, the shape of the tightening strip 4 and the fastening structure with the end plate 3 can appropriately utilize known structures. For example, it is also possible to configure the tightening strip to be flat instead of being bent into an L-shape, and to be screwed to the side surface of the end plate. Alternatively, it is also possible to configure the tightening strip to be a step-shaped engaging structure at the portion of the tightening strip facing the side surface of the end plate, and then to screw it to the side surface of the end plate using the locking structure.

[0081] In addition, an insulating sheet may be interposed between the tie bar 4 and the battery stack 2. The insulating sheet is made of a material having insulating properties, such as resin, and insulates the metal tie bar 4 from the battery cell 1.

[0082] (Bottom plate 9)

[0083] like Figure 1 to Figure 3 As shown, the bottom plate 9 is arranged on the bottom surface of the battery stack 2 and the end plate 3. The bottom plate 9 is used to fix the end plate 3, and more preferably, the lower end of the tightening bar 4 is also fixed. The end plate 3 and the tightening bar 4 are fixed to the bottom plate 9 by means of fixing screws 15 and 16. The fixing screws 15 for fixing the end plate 3 penetrate the end plate 3 in the up-down direction and fix the end plate 3 to the bottom plate 9. In addition, the fixing screws 16 for fixing the tightening bar 4 also penetrate the lower side connecting piece 4B which is the lower end of the tightening bar 4 and are fixed to the bottom plate 9.

[0084] In the battery stack 2, each battery cell 1 is brought into contact with the base plate 9 and configured in a thermal coupling state with the base plate 9. In the battery cell 1 thermally coupled with the base plate 9, the heat energy is dissipated to the base plate 9. Moreover, the base plate 9 can also be forced to cool to dissipate the heat energy of the battery cell 1 more efficiently. Although not shown in the figure, a refrigerant or a coolant can be circulated inside the base plate 9 that is forced to cool to perform forced cooling. In addition, for the base plate, a heat sink can be provided on the lower surface to perform forced cooling. Moreover, a cooling plate can be stacked on the lower surface of the base plate in a surface contact state, and forced cooling can be performed using the cooling plate. For the cooling plate, a refrigerant or a coolant can be circulated inside to perform forced cooling.

[0085] (Gas channel 5)

[0086] like Figure 3 and Figure 4 As shown, the gas passage 5 is disposed at a position facing the upper surface of the battery cell 1 , that is, the terminal surface 1X of the battery cell 1 , and discharges the exhaust gas ejected from the exhaust valve 1 a to the outside. Figure 4 The gas channel 5 shown is arranged at the center of the electrode surface 2X of the battery stack 2 in a posture extending along the stacking direction of the battery cells 1. The gas channel 5 is cylindrical in shape with an internal volume for smoothly discharging the exhaust discharged from the opening of the exhaust valve 1a, is open at the lower surface, and is connected to the opening of the exhaust valve 1a of each battery cell 1. Figure 4 The gas channel is configured to be a rectangular quadrangular tube with a cross-sectional shape having a wide horizontal width. The gas channel 5 is arranged on the upper surface of the battery stack 2 in a manner that does not form a gap between the upper surface of the battery stack 2 and the terminal surface 1X of the battery cell 1, and the opening 5a opened on the lower surface is connected to the exhaust valve 1a of each battery cell 1, so that the exhaust gas discharged from the exhaust valve 1a is discharged to the outside. The gas channel 5 can also be configured to be provided with a gasket, a sealing material, etc. between the terminal surface 1X to prevent the exhaust gas from leaking.

[0087] Furthermore, although not shown, the gas channel can also be composed of a collection channel and a branch channel, wherein the collection channel is arranged on the upper surface of the battery stack in a posture extending along the stacking direction of the battery cells, and the branch channel is connected to the collection channel and the top end is connected to the exhaust valve. In this gas channel, the collection channel can be arranged separately from the terminal surface, and the top end of the branch channel can be connected to the opening of the exhaust valve.

[0088] (Electronic circuit block 6)

[0089] Figure 2 and Figure 4 The battery assembly 10 includes two sets of electronic circuit blocks 6. The two sets of electronic circuit blocks 6 are fixed to the outer surfaces of two end plates 3 that press and fix the battery stack 2 from both ends. Figure 5 As shown, the two groups of electronic circuit blocks 6 include a voltage detection circuit 22 for detecting the voltage of the battery cell 1. Figure 5 As shown in FIG. 1 , the voltage detection circuit 22 of each electronic circuit block 6 is connected to each battery cell 1 via a voltage detection line 19 to detect the voltage of the battery cell 1. In the battery assembly 10 in which the electronic circuit blocks 6 are divided into two groups and arranged on the end plate 3, the voltage detection line 19 can be connected to the battery cell 1 and the electronic circuit block 6 that is closer, so it is different from the reference example shown in FIG. Figure 6 Compared with the battery assembly 70 including a set of electronic circuit blocks 6, the voltage detection line 19 can be shortened. Figure 4 In the battery assembly 10, the battery cells 1 are divided into two groups of battery cells 2A in the middle of the stacking direction, and the battery cells 1 of each battery cell 2A are connected to each electronic circuit block 6 by means of the voltage detection line 19. In the battery assembly 10 in which the battery stack 2 is divided into two in the middle, the longest voltage detection line 19 can be connected relative to Figure 6 The battery assembly including a set of electronic circuit blocks 6 is shown shortened to 1 / 2 the length.

[0090] exist Figure 4 In the battery assembly 10, the voltage detection line 19 is arranged on both sides of the gas channel 5 along the side edge of the gas channel 5. In the battery assembly 10, the number of voltage detection lines 19 arranged on both sides of the gas channel 5 is reduced, and the wiring space of the voltage detection line 19 can be reduced. For the voltage detection line 19 with a smaller wiring space, the horizontal width of the gas channel 5 arranged in the central part thereof can be expanded, and the exhaust gas can be smoothly discharged to prevent gas leakage. A plurality of voltage detection lines 19 are arranged on the upper surface of the battery stack 2 as a wiring harness or a printed substrate 39. In particular, the battery assembly 10 in which the printed substrate 39 of the voltage detection line 19 is set as a flexible printed substrate 39A (FPC) has the advantage of being able to make the wiring space of the voltage detection line 19 extremely thin.

[0091] Figure 2 , Figure 4 as well as Figure 7The electronic circuit block 6 shown includes a connection terminal 37 for connecting the voltage detection line 19 as a flexible printed substrate 39A. The flexible printed substrate 39A in the figure has a connector 38 for connecting to the electronic circuit block 6 at one end, and the connector 38 can be connected simply and reliably by connecting it to the connection terminal 37 provided on the electronic circuit block 6. For the electronic circuit block 6 shown in the figure, the overall outer shape is set to a relatively thin box shape so that it can be arranged along the outer surface of the end plate, and the connection terminals 37 for connecting the connector 38 are provided at both ends of its upper surface. This structure can easily arrange the flexible printed substrate 39A connected to the connection terminal 37 at a position that does not interfere with the gas channel 5. However, the connection terminal can also be arranged at the center of the upper surface of the box-shaped electronic circuit block. In this case, by bending the top end of the voltage detection line (flexible printed substrate) connected to the connection terminal in a crank shape, the connector can be connected to the connection terminal, and the main body of the voltage detection line (flexible printed substrate) is arranged on both sides of the gas channel.

[0092] In the electronic circuit block 6, electronic components for realizing the voltage detection circuit 22 are mounted on the circuit board 20 (see Figure 5 and Figure 8 However, the electronic circuit block 6 can also be configured as follows: all electronic circuits including the voltage detection circuit 22 are configured as integrated circuits, and the integrated circuits are embedded in a package of insulating material. Figure 5 and Figure 8 As shown, the electronic circuit block 6 can be a block of a metal plate with a heat sink 21 disposed on the surface. The heat sink 21 is thermally coupled to the heat generating components built into the electronic circuit block 6, such as the discharge resistor of the cell balance adjustment circuit, the semiconductor elements such as the FET for regulating the current, etc., and dissipates the heat energy of these heat generating components to the outside. The electronic circuit block 6 is formed into a plate shape by mounting electronic components on the circuit substrate 20, or is formed into a plate shape by embedding the integrated circuit in the package.

[0093] The electronic circuit block 6 including the voltage detection circuit 22 detects the voltage of the battery cell 1 whose voltage fluctuates during charging and discharging, and keeps the battery voltage within a set range to prevent overcharging and overdischarging of each battery cell 1. In the battery assembly 10, the electronic circuit block 6 may also be provided with a control circuit 30 for regulating the charging and discharging current of the battery stack 2. The control circuit 30 regulates the charging and discharging current to prevent overcharging and overdischarging of the battery cell 1. The voltage detection circuit 22 transmits the voltage data of the battery cell 1 to the control circuit 30. The electronic circuit block may also transmit battery information to an external control circuit instead of providing a control circuit, and use the external control circuit to regulate the charging and discharging current of the battery assembly 10.

[0094] The voltage detection circuit 22 preferably detects the voltage of all battery cells 1. However, the voltage detection circuit 22 does not necessarily detect the voltage of all battery cells 1. For example, the battery cells 1 constituting the battery stack 2 can be divided into a plurality of battery cells and the voltage of each battery cell can be detected. In a battery cell in which a plurality of battery cells 1 are connected in parallel, the voltage of the battery cell is detected to detect the voltage of all battery cells. In a battery cell in which a plurality of battery cells are connected in series, the voltage of the battery cell is detected to detect the total voltage of the battery cells connected in series. A battery cell in which a plurality of battery cells are connected in series is composed of 2 to 5 battery cells. In this battery cell, the voltage of the battery cell is detected to detect the total voltage of 2 to 5 battery cells 1, so the voltage of the battery cell becomes 1 / 2 to 1 / 5 of the total voltage detected. The voltage of the battery cell 1 changes according to the remaining capacity. The voltage of the battery cell 1 is higher than the preset maximum voltage when overcharged, and lower than the minimum voltage when overdischarged. The electrical characteristics of the battery cell 1 are reduced and degraded when overcharged or overdischarged, and the safety is also reduced. The voltage detection circuit 22 detects the voltage of the battery cell 1 and transmits it to the control circuit 30 . The control circuit 30 regulates the charge and discharge current so that the voltage of the battery cell 1 is within a set range.

[0095] In the battery assembly 10, as charging and discharging are repeated, the remaining capacity and voltage of each battery cell 1 become unbalanced. The battery cells 1 connected in series are charged and discharged with the same current. Although charged and discharged with the same current, the electrical characteristics of each battery cell 1 are not exactly the same. Therefore, in the battery assembly 10 in which a plurality of battery cells 1 are connected in series, as charging and discharging are repeated, the voltage and remaining capacity of each battery cell 1 become unbalanced. The imbalance of the battery cells 1 causes overcharging or overdischarging of a specific battery cell 1. In the battery assembly 10, all the battery cells 1 are charged and discharged at the same time, so the imbalance of the battery cells 1 causes overcharging or overdischarging of a specific battery cell 1. Overcharging and overdischarging of the battery cells 1 cause the electrical characteristics of the battery cells 1 to be reduced and deteriorated, and reduce the safety of the battery assembly 10. The cell balance adjustment circuit 23 eliminates the imbalance of the voltage of the battery cells 1.

[0096] The electronic circuit block 6 is also equipped with a cell balance adjustment circuit 23 for equalizing the voltage of the battery cells 1. The cell balance adjustment circuit 23 uses the voltage detection line 19 to discharge the battery cells 1 with higher voltage and charge the battery cells 1 with lower voltage, thereby equalizing the voltage of the battery cells 1 and eliminating the imbalance. An example of a circuit diagram of the cell balance adjustment circuit 23 is shown in Figure 5. Since the voltage of the battery cell 1 with a larger remaining capacity becomes higher, the remaining capacity can be balanced by discharging the battery cell 1 with a higher voltage. The single cell balance adjustment circuit 23 shown in the figure uses the discharge resistor 25 to discharge the battery cell 1 with a higher voltage to eliminate the imbalance. However, the single cell balance adjustment circuit 23 is not specific to a circuit that uses the discharge resistor 25 to discharge the battery cell 1. For example, the single cell balance adjustment circuit can also eliminate the voltage difference of the battery cell by discharging the battery cell with a higher voltage to a storage device such as a capacitor or a storage battery, thereby storing electricity in the storage device and discharging the charge of the storage device to the battery cell with a lower voltage. In addition, the single cell balance adjustment circuit can also use a DC / DC converter to convert the voltage of the battery cell with a higher voltage and charge the battery cell with a lower voltage while regulating the current to balance the voltage.

[0097] Figure 5 The cell balance adjustment circuit 23 includes a discharge circuit 24 formed by connecting a switch element 26 in series with a discharge resistor 25, and connects a control circuit 27 and a voltage detection circuit 22. The control circuit 27 detects the cell voltage of each cell and controls the switch element 26 to be turned on / off. The voltage detection circuit 22 detects the cell voltage of each battery cell 1. The discharge circuit 24 including the discharge resistor 25 and the switch element 26 is connected in parallel to each battery cell 1. In the cell balance adjustment circuit 23, when the cell voltage of the battery cell 1 becomes high, the switch element 26 is switched on by the control circuit 27, and the battery cell 1 is discharged by the discharge resistor 25 to reduce the voltage of the battery cell 1 and balance it.

[0098] The cell balance adjustment circuit 23 is driven by receiving power from the battery stack 2. The cell balance adjustment circuit 23 in the figure operates by the output voltage (Vcc) of the power supply circuit 28 which receives power from the battery stack 2. The voltage of the battery stack 2 can be reduced by, for example, a DC / DC converter as the power supply circuit 28 and supplied to the cell balance adjustment circuit 23. According to this circuit structure, even if the voltage of the battery stack 2 is high, it can be supplied to the cell balance adjustment circuit 23 as an optimal voltage.

[0099] In the control circuit 27, the cell voltages of the individual battery cells 1 are compared, and the switch element 26 is controlled to balance the cell voltages of all the battery cells 1. The control circuit 27 switches the switch element 26 of the discharge circuit 24 connected to the battery cell 1 with excessive voltage to on, so that the excessive battery cell 1 is discharged. The voltage of the battery cell 1 decreases as it discharges. When the voltage of the battery cell 1 decreases to balance with the other battery cells 1, the switch element 26 switches from on to off. When the switch element 26 becomes off, the discharge of the battery cell 1 stops. In this way, the control circuit 27 discharges the battery cell 1 with a higher cell voltage and balances the cell voltages of all the battery cells 1.

[0100] The above-mentioned single-cell balancing adjustment circuit 23 balances the voltages of all battery cells 1, but in the battery assembly, all battery cells can also be divided into a plurality of battery units, and after the voltages of the battery cells constituting the battery units are balanced by the single-cell balancing adjustment circuit, the voltage of the entire battery unit is balanced by the unit-cell balancing adjustment circuit. The unit-cell balancing adjustment circuit detects the cell voltage of each battery cell, discharges the battery cell with a higher cell voltage, and balances the voltages of each battery cell.

[0101] The electronic circuit block 6 is fixed to the end plate 3 and dissipates heat to the end plate 3. The electronic circuit block 6 includes semiconductor elements such as FETs that control current, and heat generating elements such as discharge resistors. The electronic circuit block 6 can reduce the temperature rise by dissipating the heat energy of the heat generating elements to the end plate 3. The temperature rise of the electronic circuit block 6 has an adverse effect on the built-in heat generating elements and the like. In particular, for the single-cell balancing adjustment circuit 23, the discharge resistor 25 is used to discharge the battery cell 1 to reduce the voltage, but the discharge resistor 25 is heated by the Joule heat of the discharge current. The discharge resistor 25 can increase the current to quickly reduce the voltage of the battery cell 1 in a short time, but the Joule heat generated by the discharge resistor 25 increases in proportion to the square of the discharge current, so the heat energy generated by the single-cell balancing adjustment circuit 23 that can quickly reduce the voltage of the battery cell 1 and shorten the equalization time increases. The single-cell balancing adjustment circuit 23 balances the battery cell 1 when the battery cell 1 is not charged or discharged, so it is required to further shorten the equalization time. The equalization time can be shortened by increasing the current of the discharge resistor 25 . Therefore, how to efficiently dissipate the heat energy generated by the discharge resistor 25 becomes an important factor in determining the equalization time.

[0102] The temperature rise caused by the heat energy of the heat-generating components leads to the failure of the components. Therefore, in order to avoid the abnormal temperature rise of the heat-generating components, the design is made to enlarge the whole or reduce the heat generation per unit time of the discharge resistor, etc. If the electronic circuit block 6 is miniaturized so that it can be configured in a small space, the heat dissipation area is reduced, the heat dissipation energy is reduced, and the temperature rise becomes larger. Therefore, like the previous battery assembly, the heat dissipation area of ​​the electronic circuit block that is miniaturized to be configured in the tiny space of the gas channel and the bus bar becomes smaller, so it is necessary to reduce the heat dissipation energy. Therefore, the electronic circuit block configured in a small space needs to reduce the heat dissipation energy, which prolongs the time for balancing the battery cells. The battery assembly of stacked multiple battery cells is used as a battery assembly for driving the electric motor of the vehicle for large-capacity purposes, the power supply of the storage device, etc., so the capacity of the battery cell is also quite large. In a large-capacity battery assembly, as the capacity of the battery cell increases, the imbalance of the capacity caused by the imbalance of the battery cell voltage is relatively enlarged. Therefore, this battery assembly shortens the equalization time of the battery cells as much as possible and equalizes quickly, so that the discharge current can be increased. However, the heat energy generated due to the increase in discharge resistance increases, so it is required to increase the heat dissipation area. Therefore, the electronic circuit block is required to be miniaturized in order to be arranged in a small space, and the heat dissipation area needs to be increased and enlarged in order to discharge with a large current to shorten the equalization time. Therefore, in the electronic circuit block, miniaturization and shortening of the equalization time are mutually contradictory characteristics, and it is impossible to satisfy both characteristics, and it is required to have contradictory issues such as miniaturization required for arrangement in a limited space and enlargement for having a higher discharge capacity.

[0103] In the battery assembly 10 in which the electronic circuit block 6 is fixed to the end plate 3 in a thermally coupled state and the end plate 3 is used for heat dissipation of the electronic circuit block 6, the end plate 3 can be used to efficiently dissipate the heat energy generated by the electronic circuit block 6. In particular, the specific heat capacity of the end plate 3 is extremely large, and the temperature rise relative to the absorbed heat energy is small, which can shorten the equalization time of the battery cell 1. In addition, the surface area of ​​the end plate 3 is also large, and the heat energy dissipated from the surface is also large, which also leads to a smaller temperature rise. Moreover, in the structure in which the end plate 3 is fixed to the bottom plate 9, the temperature rise is further reduced by conducting heat energy from the end plate 3 to the bottom plate 9. In addition, in the structure in which the bottom plate 9 is forced to cool or a cooling plate is stacked on the bottom plate 9, the temperature rise is further reduced by forcibly cooling the end plate 3 using the bottom plate 9, the cooling effect of the electronic circuit block 6 is further increased, and the temperature rise of the electronic circuit block 6 is reduced to an ideal state.

[0104] exist Figure 7 and Figure 8In the battery assembly 10, the electronic circuit block 6 is fixed to the outer surface of the end plate 3. The battery assembly 10 has the following advantages: it can conduct and dissipate the heat energy of the electronic circuit block 6 to the fixed end plate 3, and it can also dissipate the heat from the exposed surface to the outside air to dissipate the heat more efficiently. For the electronic circuit block 6 fixed to the surface of the end plate 3, its outer shape is smaller than that of the end plate 3 and does not protrude from the outer periphery of the end plate 3. In the battery assembly 10, the electronic circuit block 6 is arranged on the end plate 3, and the electronic circuit block 6 does not increase the outer shape of the battery assembly 10, and it is possible to efficiently dissipate the heat of the electronic circuit block 6 while miniaturizing it.

[0105] Moreover, in Figure 7 In the battery assembly 10, the thickness of the electronic circuit block 6 is set to a dimension that does not protrude from the top edge of the bottom plate 9 to the outer side surface when viewed from above. In the battery assembly 10, the electronic circuit block 6 is fixed to the end plate 3, and the outer shape when viewed from above is not larger than the bottom plate 9, so that the electronic circuit block 6 can be arranged in an ideal position while miniaturizing the entirety.

[0106] The end plate 3 is pressed from the inside with a strong pressure by the battery cell 1, which has the physical property of expanding during charge and discharge. The end plate 3, which is pressed against the battery stack 2 and fixed on both sides by the tightening strips 4, bends under the pressure of the battery stack 2. If the electronic circuit block 6 is deformed by the bent end plate 3, it will have an adverse effect on the components of the electronic circuit block 6. For example, in the electronic circuit block 6 where the electronic components are fixed to the circuit substrate, the circuit substrate bends and the conductive part is damaged. Figure 8 For the electronic circuit block 6, a part of the upper edge, preferably the central part, is locally fixed to the end plate 3, and the lower part is fixed to the top end of the bottom plate 9. In this battery assembly 10, even if the battery cell 1 expands and the end plate 3 is deformed, the deformation will not have an adverse effect on the electronic circuit block 6. In the above battery assembly 10, a part of the upper edge of the electronic circuit block 6 is locally fixed to the end plate 3, so even if the end plate 3 is bent, it will not deform together. In addition, for the electronic circuit block 6, the lower part is fixed to the top end of the bottom plate 9, so it is reliably fixed at the upper and lower parts. That is, the electronic circuit block 6 is firmly fixed to the end plate 3 and the bottom plate 9 without being adversely affected by the deformation of the end plate 3.

[0107] The battery assembly 10 in which the electronic circuit block 6 is fixed to the bottom plate 9 has the following advantages: by arranging the electronic circuit block 6 at a position different from the fixing hole 17 when viewed from above, the electronic circuit block 6 can be fixed to the end plate 3, and the bottom plate 9 can be simply and reliably fixed to the chassis of the vehicle or other equipment. Figure 7 In the battery assembly 10, fixing holes 17 are provided on both sides of the bottom plate 9, and the interval between the fixing holes 17 is set to a lateral width that allows the electronic circuit block 6 to be arranged therebetween.

[0108] The electronic circuit block 6 is preferably fixed to the end plate 3 in an insulated manner. The electronic circuit block 6 is fixed by configuring an insulating sheet 18 between the end plate 3. The insulating sheet 18, as an elastic sheet composed of a rubber-like elastic body, can always keep the bent end plate 3 and the electronic circuit block 6 in a thermally coupled state. For the electronic circuit block 6 fixed to the end plate 3 in an insulated manner, a structure is set to expose a metal heat sink 21 or the like to the surface so that heat can be efficiently dissipated, and the insulation characteristics can be improved relative to the battery stack 2 configured on the inner side of the end plate 3 to improve reliability. For the battery assembly 10 in which the end plate 3 is configured on both end surfaces of the battery stack 2, electric shock and leakage can be prevented by insulating the end plate 3 from the ground. The end plate 3 insulated from the ground is configured with a high-voltage battery stack 2 on the inside. For the end plate 3 insulated from the battery stack 2, the leakage resistance with the battery stack 2 is kept high, but sometimes the leakage resistance is reduced due to various reasons. For example, condensed water between the end plate 3 and the battery stack 2 becomes a cause of reducing leakage resistance. Even if the contact resistance between the end plate 3 and the battery stack 2 is reduced, the electronic circuit block 6 insulated from the end plate 3 is also insulated from the end plate 3, preventing the disadvantages of leakage, electric shock, etc. and ensuring high safety and reliability. However, since the end plate is insulated from the battery stack, it is also possible to connect the end plate to the ground wire.

[0109] The above battery assembly 10 has the following advantages: the heat generated by the heat generating components of the cell balance adjustment circuit 23 of the electronic circuit block 6 can be efficiently dissipated by the end plate 3, so that the battery cells 1 can be quickly balanced by the cell balance adjustment circuit 23. The reason is that by increasing the power consumption of the cell balance adjustment circuit 23 and discharging the battery cells 1 with a large current, the voltage of the high-voltage battery cells 1 can be quickly reduced. The cell balance adjustment circuit 23 eliminates the voltage imbalance by discharging the high-voltage battery cells 1, or charges the low-voltage battery cells 1 with the high-voltage battery cells 1 to balance. In the circuit that balances by discharging the high-voltage battery cells 1, the high-voltage battery cells 1 are discharged by the discharge resistor 25, and in the cell balance adjustment circuit 23 that charges the low-voltage battery cells 1 with the high-voltage battery cells 1, power is supplied from the high-voltage battery cells 1 to the low-voltage battery cells 1 to balance. In a circuit that uses a discharge resistor 25 to discharge a battery cell 1 for equalization, the discharge resistor 25 that discharges the battery cell 1 and the switch element 26, that is, the semiconductor element that regulates the discharge current of the discharge resistor 25 generate heat. For this circuit, a structure that efficiently dissipates the heat energy of the discharge resistor 25 and the semiconductor element can increase the discharge current of the discharge resistor 25 and the semiconductor element and shorten the equalization time. If the discharge current is increased, the heat generated also increases, so it is possible to discharge efficiently and increase the discharge current. In addition, in a cell balancing adjustment circuit that uses a high-voltage battery cell to charge a low-voltage battery cell, the semiconductor element that regulates the current from the high-voltage battery cell to the low-voltage battery cell generates heat, so the current of the semiconductor element can be increased and the equalization time can be shortened.

[0110] like Figure 5 As shown by the dotted line, the electronic circuit block 6 fixed to the end plate 3 is provided with a wireless communication circuit 31, which can wirelessly transmit information such as the battery voltage detected by the voltage detection circuit 22 to the central control circuit 33. The electronic circuit block 6 has the following advantages: it does not need to be connected to the central control circuit 33 using external connection wires, and can be simply wired. In particular, in a battery assembly mounted on a vehicle, the electronic circuit block 6 can wirelessly transmit information to the central control circuit 33 that controls the vehicle's driving motor. In a battery assembly of this structure, the vehicle's unique and complex wiring harness is simplified, and the disadvantages such as poor contact that are unavoidable in the wiring harness are prevented, and high reliability can be achieved over a long period of time.

[0111] The electronic circuit block 6 including the wireless communication circuit 31 requires a characteristic that can eliminate transmission errors caused by external noise. The metal end plate 3 can shield the surface of the electronic circuit block 6 and reduce the influence of external noise. In particular, Fig. 9As shown, the end plate 3 integrally provided with the shielding protrusion 32 shielding the outer periphery of the electronic circuit block 6 enables the wireless communication circuit 31 to stably and accurately transmit information wirelessly. Moreover, by connecting the end plate to the ground line, the shielding effect can be improved and the influence of external noise can be further reduced.

[0112] Furthermore, the electronic circuit block 6 includes a communication circuit (not shown) for transmitting signals by cascading a plurality of electronic circuit blocks 6. The communication circuit is connected to the communication terminal 43 by means of a coupling element 46. The communication circuit transmits the signal alternately transmitted between the mutually connected detection circuit blocks 6 to the coupling element 46. The communication terminal 43 is used as a terminal for connecting the electronic circuit blocks 6 arranged on both sides of the battery assembly 10 to each other, or is used as a terminal for connecting the electronic circuit blocks 6 of a plurality of battery assemblies 10. The electronic circuit blocks 6 arranged on both sides of one battery assembly 10 are connected to each other by means of an internal communication line 45. In addition, the electronic circuit blocks 6 of different battery assemblies 10 are connected to each other by means of an external communication line 44. The illustrated electronic circuit block 6 includes a plurality of communication terminals 43, and these communication terminals 43 are provided as a common terminal structure that can be connected to both the internal communication line 45 and the external communication line 44.

[0113] like Figure 2 , Figure 4 as well as Figure 7 As shown, the electronic circuit block 6 can have a pair of communication terminals 43 on the left and right. In a pair of communication terminals 43, one is connected to the electronic circuit block with the upper potential, and the other is connected to the lower electronic circuit block. However, in the case of an insulating communication circuit such as the communication method using the coupling capacitor described above, the potential can be ignored, so each communication terminal 43 becomes a structure that can communicate with either the upper electronic circuit block or the lower electronic circuit block. Therefore, the electronic circuit block 6 of this structure has the following characteristics: in a state where it is arranged on both sides of the battery assembly, it is possible to select any one of the communication terminals 43 on the left and right and connect the internal communication line 45 and the external communication line 44, so that the communication line can be efficiently wired. That is, the electronic circuit blocks 6 arranged on both sides of the battery assembly 10 use the same structure, and select the connection positions of the internal communication line 45 and the external communication line 44, so that ideal wiring can be achieved. The illustrated electronic circuit block 6 is provided with a pair of communication terminals 43 on the left and right of the upper surface. As shown in the figure, a pair of communication terminals 43 formed on the upper surface of the electronic circuit block 6 can be provided on the inner side of the connection terminals 37 formed at both ends, or, although not shown, can also be provided on the outer side of the connection terminals. Furthermore, although not shown, in the electronic circuit block, a pair of communication terminals can also be provided on the left and right side surfaces instead of the upper surface, or a pair of communication terminals can be provided on the left and right side surfaces in addition to the upper surface.

[0114] (Power supply device 100)

[0115] like Fig.10 and Fig.11 As shown, by connecting a plurality of battery assemblies 10 in series and in parallel using a power line 42, a large-capacity power supply device 100 can be realized. The large-capacity power supply device 100 can be effectively used as a power supply for electric vehicles such as hybrid vehicles and electric vehicles, and can also be effectively used as a power storage device. The power supply device 100 connects adjacent battery assemblies 10 using a power line 42 and an external communication line 44. The power line 42 is connected to the output terminal 41 of the battery assembly 10, and the battery assembly 10 is connected in series and in parallel. The external communication line 44 is connected to the communication terminal 43, which is provided in the electronic circuit block 6 and is located at the end of the battery assembly 10 connected by the power line 42. In the power supply device 100, both the power line 42 and the external communication line 44 are connected to the ends on the same side of the battery assembly 10, and the external communication line 44 is connected to the adjacent battery assembly 10 at the shortest distance. Here, the ends on the same side of the battery assembly 10 refer to the ends on the side close to each other.

[0116] The power supply device 100 includes a plurality of battery modules 10, each of which includes two sets of electronic circuit blocks 6. In the power supply device 100, all the electronic circuit blocks 6 are connected in cascade. In the power supply device 100, by connecting all the electronic circuit blocks 6 in cascade, that is, in series, signals from all the battery modules 10 are transmitted to the outside using a single line. It is also possible to transmit signals to the outside independently from each electronic circuit block 6, but in this circuit structure, the same number of lines as the number of electronic circuit blocks is required, so the signal transmission line for transmitting signals to an external control circuit or the like arranged outside becomes complicated.

[0117] In a power supply device 100 in which a plurality of battery assemblies 10 are connected in series, a cascade connection cannot be performed because a potential difference is generated in the ground line of each battery assembly 10. The communication terminal 43 of each electronic circuit block 6 uses the ground line as a reference potential to transmit a signal, so it is impossible to connect a plurality of communication terminals 43 in series where there is a potential difference in the ground line. This disadvantage can be eliminated in the following manner: a bias voltage is applied to the ground line of the electronic circuit block 6 where there is a potential difference, the DC level of the ground line is changed, and the potential difference of the ground line of the connected communication terminal 43 is set to zero level. However, in this circuit structure, the circuit for applying the bias voltage becomes complicated, and it is also necessary to prevent the temperature change of the bias voltage, and the circuit structure becomes further complicated.

[0118] In order to prevent the above disadvantages, the communication terminals 43 of all the electronic circuit blocks 6 are connected in cascade, and the electronic circuit block 6 has a communication terminal 43 that transmits a signal by connecting a plurality of electronic circuit blocks 6 in cascade. Fig.11As shown, the communication terminal 43 is internally connected by means of a coupling element 46 that blocks direct current and passes alternating current signals. The coupling element 46 can be any one of a coupling capacitor, a transformer for signal transmission, and a photoelectric transmission element. This electronic circuit block 6 has the following advantages: since the direct current component is cut off by the coupling element 46 and only the alternating current signal is transmitted to the communication terminal 43, the communication terminals 43 of multiple electronic circuit blocks 6 can be cascade-connected to transmit signals at the direct current level of the ground line of the communication terminal 43 without adjustment. This is particularly effective in a device in which multiple battery modules 10 are connected in series.

[0119] The battery assembly 10 includes two groups of electronic circuit blocks 6, and each electronic circuit block 6 is arranged on an end plate 3 provided at both ends of the battery stack 2. The two groups of electronic circuit blocks 6 provided in the battery assembly 10 are connected by an internal communication line 45, and the adjacent battery assemblies 10 are connected by an external communication line 44, so that all the electronic circuit blocks 6 are cascade-connected, and signals are transmitted to the outside using a single line. The electronic circuit block 6 includes two groups of communication terminals 43, one communication terminal 43 is connected to the internal communication line 45, and the electronic circuit blocks 6 on both sides of the battery stack 2 are connected by means of the internal communication line 45, and the other communication terminal 43 is connected to the external communication line 44, and the electronic circuit blocks of adjacent battery assemblies 10 are connected using the external communication line 44, so that all the electronic circuit blocks are cascade-connected. Moreover, in Figure 7 In the battery pack 10, the pair of communication terminals 43 provided in each electronic circuit block 6 is set as a common communication terminal 43 that can be connected to both the internal communication line 45 and the external communication line 44. In the battery pack 10, as Fig.10 As shown, two battery modules 10 disposed closest to each other can be connected by the power line 42 , and the communication terminals 43 provided on the two battery modules 10 connected by the power line 42 can be connected by the external communication line 44 .

[0120] The above battery assembly 10 can be used as a power source for a vehicle that supplies power to an electric motor that drives an electric vehicle. The battery assembly 10 can be used as a power source for hybrid vehicles that use both an engine and an electric motor, plug-in hybrid vehicles, or electric vehicles that use only an electric motor to drive an electric vehicle, and can be used as a power source for these vehicles. In addition, in order to obtain power to drive the vehicle, a large-capacity, high-output power supply device 100 can be constructed and mounted by connecting a plurality of the above battery assemblies 10 in series or in parallel and adding necessary control circuits.

[0121] (Power supply device for hybrid electric vehicles)

[0122] Fig.12An example of a hybrid vehicle that runs using both an engine and an electric motor is shown, in which a power supply device 100 is mounted. The vehicle HV equipped with the power supply device 100 shown in the figure includes a vehicle body 91, an engine 96 that drives the vehicle body 91 and an electric motor 93 for running, wheels 97 driven by the engine 96 and the electric motor 93 for running, a power supply device 100 that supplies power to the electric motor 93, and a generator 94 that charges the battery of the power supply device 100. The power supply device 100 is connected to the electric motor 93 and the generator 94 via a DC / AC inverter 95. The vehicle HV runs using both the electric motor 93 and the engine 96 while charging and discharging the battery of the power supply device 100. The electric motor 93 is driven in an area where the engine efficiency is poor, such as when accelerating or running at a low speed, to drive the vehicle. The electric motor 93 is driven by the power supply device 100 to supply power. The generator 94 is driven by the engine 96 or by regenerative braking when braking the vehicle, and charges the battery of the power supply device 100. Furthermore, as shown in the figure, the vehicle HV may include a charging plug 98 for charging the power supply device 100. The power supply device 100 can be charged by connecting the charging plug 98 to an external power supply.

[0123] (Power supply device for electric vehicles)

[0124] in addition, Fig.13 An example of an electric vehicle that runs only with an electric motor is shown in which a power supply device is mounted. The vehicle EV equipped with a power supply device 100 shown in the figure includes a vehicle body 91, a motor 93 for driving the vehicle body 91, wheels 97 driven by the motor 93, a power supply device 100 that supplies power to the motor 93, and a generator 94 that charges the battery of the power supply device 100. The power supply device 100 is connected to the motor 93 and the generator 94 via a DC / AC inverter 95. The motor 93 is driven by the power supply device 100 supplying power. The generator 94 is driven by the energy when the vehicle EV is regeneratively braked, and charges the battery of the power supply device 100. In addition, the vehicle EV is equipped with a charging plug 98, and the charging plug 98 can be connected to an external power source to charge the power supply device 100.

[0125] (Power supply device for power storage device)

[0126] The present invention does not limit the use of the power supply device to the power supply of the motor for driving the vehicle. The power supply device of the embodiment can also be used as a power supply of a power storage device that charges and stores electricity in a battery using electricity generated by solar power generation, wind power generation, etc. Fig.14 The power storage device that charges and stores electricity in the battery of the power supply device 100 using the solar cell 82 is shown.

[0127] Fig.14The power storage device shown in the figure charges the battery of the power supply device 100 using the power generated by the solar cell 82 arranged on the ridge, roof, etc. of the building 81 such as a house or a factory. In the power storage device, after the battery of the power supply device 100 is charged by the charging circuit 83 using the solar cell 82 as a charging power source, the power is supplied to the load 86 via the DC / AC inverter 85. Therefore, the power storage device has a charging mode and a discharging mode. In the power storage device shown in the figure, the DC / AC inverter 85 and the charging circuit 83 are connected to the power supply device 100 via the discharging switch 87 and the charging switch 84, respectively. The on / off of the discharging switch 87 and the charging switch 84 are switched by the power supply controller 88 of the power storage device. In the charging mode, the power supply controller 88 switches the charging switch 84 to on and switches the discharging switch 87 to off, allowing the charging of the power supply device 100 from the charging circuit 83. In addition, when charging is completed and the battery is fully charged, or when the battery is charged to a capacity greater than a predetermined value, the power controller 88 turns off the charging switch 84 and turns on the discharging switch 87 to switch to the discharging mode, allowing the power supply device 100 to discharge to the load 86. In addition, the charging switch 84 can be turned on and the discharging switch 87 can be turned on as needed, and power can be supplied to the load 86 and charged to the power supply device 100 at the same time.

[0128] Furthermore, although not shown in the figure, the power supply device can also use a power supply for a power storage device that uses the late night power to charge and store electricity in the battery. The power supply device charged by the late night power can use the late night power as the surplus power of the power station to charge, output power during the daytime when the power load is large, and limit the peak power during the daytime to a small value. Furthermore, the power supply device can also use a power supply that uses both the output of the solar cell and the late night power to charge. This power supply device effectively uses both the power generated by the solar cell and the late night power, and can store electricity efficiently while taking into account the weather and power consumption.

[0129] The power storage device as described above can be appropriately used as a backup power supply device that can be mounted on a rack of a computer server, a backup power supply device for a wireless base station for a mobile phone, etc., a power supply for power storage at home or in a factory, a power supply for street lights, a power storage device combined with a solar cell, and a backup power supply for a signal light, a traffic display for a road, etc.

[0130] Industrial Applicability

[0131] The battery pack and power supply device of the present invention can be appropriately used as a power supply for a plug-in hybrid electric vehicle, a hybrid electric vehicle, an electric vehicle, etc. that can switch between an EV driving mode and an HEV driving mode. In addition, it can also be appropriately used as a backup power supply that can be mounted on a rack of a computer server, a backup power supply for a wireless base station such as a mobile phone, a power supply for power storage for home use and factory use, a power supply for street lights, a power storage device combined with a solar cell, a backup power supply for a signal light, etc.

[0132] Description of Reference Numerals

[0133] 100. Power supply device; 1. Battery cell; 1a. Exhaust valve; 1X. Terminal surface; 2. Battery stack; 2A. Battery unit; 2X. Electrode surface; 3. End plate; 4. Tightening strip; 4A. Fixing portion; 4B. Lower connecting piece; 4C. Pressing piece; 5. Gas passage; 5a. Opening; 6. Electronic circuit block; 8. Cover; 9. Bottom plate; 10. Battery assembly; 11. Electrode terminal; 12. Insulating spacer; 13. End surface spacer; 14 , bus bar; 15, fixing screw; 16, fixing screw; 17, fixing hole; 18, insulating sheet; 19, voltage detection line; 20, circuit substrate; 21, heat sink; 22, voltage detection circuit; 23, single cell balance adjustment circuit; 24, discharge circuit; 25, discharge resistor; 26, switch element; 27, regulation circuit; 28, power supply circuit; 30, control circuit; 31, wireless communication circuit; 32, shielding convex part; 33, central control circuit 37. Connecting terminal; 38. Connector; 39. Printed circuit board; 39A. Flexible printed circuit board; 41. Output terminal; 42. Power line; 43. Communication terminal; 44. External communication line; 45. Internal communication line; 46. Coupling element; 70. Battery pack; 81. Building; 82. Solar cell; 83. Charging circuit; 84. Charging switch; 85. DC / AC inverter; 86. Load; 87. Discharge switch; 88. Power controller; 91. Vehicle body; 93. Motor; 94. Generator; 95. DC / AC inverter; 96. Engine; 97. Wheel; 98. Charging plug; 900. Battery pack; 901. Battery cell; 902. Battery stack; 903. End plate; 904. Tightening strip; 905. Gas channel; 906. Circuit board; 910. Terminal surface; 911. Electrode terminal; 914. Bus bar; HV, EV, vehicle.

Claims

1. A battery assembly, characterized in that: The battery assembly includes: a battery stack formed by stacking a plurality of battery cells; a pair of end plates disposed at both ends of the battery stack in a stacking direction; a tie bar connecting the pair of end plates; and an electronic circuit block formed by installing a voltage detection circuit for detecting the voltage of the battery cells. The two electronic circuit blocks are respectively disposed on the outer surfaces of the two end plates disposed at the two ends of the battery stack. Each electronic circuit block is connected to the battery cell via a voltage detection line. The battery stack includes a gas passage connected to an opening of a gas exhaust valve provided in the battery cell. The gas channel is arranged at the center of the electrode surface of the battery stack so as to extend along the stacking direction of the battery cells. The voltage detection line is arranged along the side edge of the gas channel, The voltage detection lines located on the same side of the gas channel include a first voltage detection line and a second voltage detection line. The first voltage detection line and the second voltage detection line are independent of each other, the first voltage detection line is closer to one of the two electronic circuit blocks, and the second voltage detection line is closer to the other of the two electronic circuit blocks, The first voltage detection line is connected to one of the two electronic circuit blocks. The second voltage detection line is connected to the other of the two electronic circuit blocks.

2. The battery assembly according to claim 1, characterized in that: The battery stack composed of a plurality of the battery cells is divided into a plurality of battery units in the middle of the stacking direction of the battery cells. Each of the battery cells is connected to each of the electronic circuit blocks via the voltage detection line.

3. The battery assembly according to claim 1, characterized in that: The voltage detection lines are arranged on both sides of the gas channel.

4. The battery assembly according to claim 1 or 2, characterized in that: The electronic circuit block includes a cell balance adjustment circuit for adjusting the cell balance of each of the battery cells. The cell balance adjustment circuit energizes the voltage detection line to adjust the cell balance of each of the battery cells.

5. The battery assembly according to claim 1 or 2, characterized in that: The voltage detection line is a wiring harness or a printed circuit board.

6. The battery assembly according to claim 5, characterized in that: The printed substrate of the voltage detection line is a flexible printed substrate (FPC).

7. The battery assembly according to claim 1 or 2, characterized in that: The electronic circuit block includes a communication terminal that can transmit signals by cascading a plurality of the electronic circuit blocks. The communication terminals are internally connected via a coupling element that blocks direct current and passes alternating current signals.

8. The battery assembly according to claim 7, characterized in that: The coupling element is any one of a coupling capacitor, a transformer, and an optoelectronic transmission element.

9. A power supply device comprising a plurality of battery modules according to claim 7, characterized in that: The power supply device includes a power line and an external communication line connecting adjacent battery assemblies. The power line is connected to the output terminal of the battery assembly, The external communication line is connected to the communication terminal, The external communication line is connected to the communication terminal located at the end of the battery pack connected to the power line, The power line and the external communication line are both connected to ends on the same side of the battery pack.

10. The power supply device according to claim 9, characterized in that: The battery modules disposed adjacent to each other are connected to the external communication line at a pair of the communication terminals disposed closest to each other.

11. An electric vehicle comprising the power supply device according to claim 9 or 10, characterized in that: The electric vehicle comprises: the power supply device; an electric motor for driving, which is supplied with electric power by the power supply device; a vehicle body on which the power supply device and the electric motor are mounted; and The wheels are driven by the electric motor to cause the vehicle body to travel.

12. A power storage device comprising the power supply device according to claim 9 or 10, characterized in that: The power storage device comprises: the power supply device; and a power controller that controls charging and discharging of the power supply device, The power controller controls so that the battery cell can be charged with power from the outside, and the battery cell is charged.

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