Acquisition board and energy storage device

Abstract

An acquisition board and an energy storage device, the energy storage device comprises a plurality of cells and an acquisition board, the acquisition board comprises a conductive circuit layer and a balancing resistor which are stacked along the thickness direction of the acquisition board, and the conductive circuit layer is used for being electrically connected with each of the plurality of cells. And the balancing resistor is used for discharging the battery cell when one of the plurality of battery cells, the conductive circuit layer and the balancing resistor form an access. The acquisition board is used for acquiring state parameters of a battery cell in the energy storage device, such as the temperature or the voltage of the battery cell. According to the scheme, the acquisition board is integrated with the equalization resistor, and when the equalization resistor, the battery cell and the conductive circuit layer form a path, the equalization resistor can discharge the battery cell, so that the voltage of the battery cell is equalized, and the overcharge condition of the battery cell is prevented. As the equalization resistor is integrated in the acquisition board, the space of the energy storage device can be saved, and the energy density of the energy storage device is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of circuit boards, in particular to a collection board and an energy storage device. Background Art

[0002] The energy storage device has multiple battery cells. During the charging process of the energy storage device, some battery cells of the energy storage device may be fully charged, while some battery cells are not yet fully charged.

[0003] At present, in order to continue charging the energy storage device more safely, the battery cell can be connected to an external balancing resistor, which can convert the excess energy in the fully charged battery cell into heat energy for consumption. However, the existing balancing resistor occupies a large space, which affects the energy density of the energy storage device. Utility Model Content

[0004] The technical problem to be solved by the utility model is to provide a collection board and an energy storage device capable of balancing voltage.

[0005] In the first aspect, the present application provides an energy storage device with a collection board, the energy storage device includes a plurality of battery cells and a collection board, the collection board includes a conductive circuit layer and a balancing resistor stacked along the thickness direction of the collection board, the conductive circuit layer is used to be electrically connected to each of the plurality of battery cells, and the balancing resistor is used to discharge the battery cell when a battery cell in the plurality of battery cells, the conductive circuit layer and the balancing resistor form a path. The collection board is used to collect state parameters of the battery cells in the energy storage device, such as the temperature of the battery cells or the voltage of the battery cells. In this solution, the collection board is integrated with a balancing resistor, and when the balancing resistor, the battery cells and the conductive circuit layer form a path, the balancing resistor can discharge the battery cells, balance the voltage of the battery cells, and prevent the battery cells from being overcharged. Since the balancing resistor is integrated in the collection board, the space of the energy storage device can be saved and the energy density of the energy storage device can be improved.

[0006] In combination with the first aspect, in a feasible implementation, the conductive circuit layer includes two equalizing conductive parts spaced apart along the width direction of the acquisition board, one end of the equalizing resistor is stacked on one of the two equalizing conductive parts, and the other end of the equalizing resistor is stacked on the other of the two equalizing conductive parts, and any one of the two equalizing conductive parts is electrically connected to a battery cell. Since the two equalizing conductive parts are spaced apart, the two ends of the equalizing resistor are respectively connected to the two equalizing conductive parts, so that the two equalizing conductive parts are connected in series through the equalizing resistor, and one of the two equalizing conductive parts is electrically connected to a battery cell. When a battery cell in a plurality of battery cells, the conductive circuit layer and the equalizing resistor form a path, the equalizing resistor can discharge the battery cell. It should be noted that the equalizing resistor can achieve the purpose of equalizing the voltage of the battery cells in the energy storage device by consuming the electric energy of the battery cell by generating heat. Exemplarily, if multiple battery cells are connected in series in the energy storage device, one of the battery cells is fully charged, and the remaining battery cells are not yet fully charged. In order to fully charge the remaining cells, the energy storage device needs to be charged. The fully charged cells can consume the electric energy of the fully charged cells through the balancing resistor to prevent the fully charged cells from being overcharged.

[0007] In combination with the first aspect, in a feasible implementation, the number of the balancing resistors is multiple, and every two adjacent balancing resistors have a spacing along the length direction of the acquisition board, one end of the multiple balancing resistors is commonly connected to one of the two balancing conductive parts, and the other end of the multiple balancing resistors is commonly connected to the other balancing conductive part of the two balancing conductive parts. There is a spacing between every two adjacent balancing resistors, which is beneficial to the heat dissipation of each balancing resistor. Multiple balancing resistors are arranged in parallel to reduce the resistance value of the balancing resistor and increase the heat dissipation surface of the balancing resistor, which is beneficial to improving the heat dissipation capacity of the balancing resistor.

[0008] In combination with the first aspect, in a feasible implementation, the balancing resistor is bent in the area between the two balancing conductive parts. The bending of the balancing resistor can increase the heat dissipation area of ​​the balancing resistor, which is conducive to improving the heat dissipation performance of the balancing resistor. When the resistance value of the balancing resistor is controlled to remain unchanged, the bending of the balancing resistor can reduce the space occupied by the balancing resistor on the acquisition board.

[0009] In combination with the first aspect, in a feasible implementation, the balancing resistor is a film-like structure, and the thickness of the balancing resistor is 1μm-100μm. By controlling the thickness of the balancing resistor, the resistance of the balancing resistor can be controlled, which is convenient for controlling the power consumption of the battery cell by the acquisition board. The thickness of the balancing resistor is 1μm-100μm, and it has a high heat dissipation area, which is conducive to the rapid heat dissipation of the acquisition board. Among them, if the balancing resistor is too thick, it is not convenient for the balancing resistor to dissipate heat when the power is turned on, and if the balancing resistor is too thin, it is difficult to form the balancing resistor. Since the thickness of the balancing resistor is 1μm-100μm, the balancing resistor can be printed on the conductive circuit layer through a printing process, which simplifies the manufacturing process of the acquisition board and can reduce the space occupied by the balancing resistor on the acquisition board.

[0010] In combination with the first aspect, in a feasible implementation, the acquisition board further includes two insulating protective layers, the two insulating protective layers are arranged at intervals along the thickness direction of the acquisition board, and the balancing resistor and the conductive circuit layer are arranged between the two insulating protective layers. The two insulating protective layers can play an insulating protective role to protect the circuit in the guide circuit layer, and the two insulating protective layers also play an anti-corrosion role to improve the anti-corrosion performance of the acquisition board.

[0011] In combination with the first aspect, in a feasible implementation, the multiple battery cells are arranged in sequence along the length direction of the collection board, the collection board is arranged on the end faces of the multiple battery cells, and the end face of each battery cell facing the collection board is provided with a positive electrode and a negative electrode, and the positive electrode and the negative electrode are electrically connected to the conductive layer circuit layer of the collection board. The collection board is arranged on the end faces where the positive electrode and the negative electrode of each battery cell are located, which can facilitate the electrical connection between the conductive circuit layer in the collection board and each battery cell, without the need to electrically connect the collection board and each battery cell through an intermediate electrical connection device, saving the space occupied by the intermediate electrical connection device and improving the energy density of the energy storage device.

[0012] In a second aspect, the present application provides an acquisition board, the acquisition board includes a conductive circuit layer and a balancing resistor, the balancing resistor is stacked on the conductive circuit layer along the thickness direction of the acquisition board. The balancing resistor is integrated in the acquisition board, and the acquisition board can play a role in balancing the cell voltage.

[0013] In combination with the second aspect, in a feasible implementation, the conductive circuit layer has two balancing conductive parts, the two balancing conductive parts are arranged at intervals along the width direction of the acquisition board, one end of the balancing resistor is stacked on one of the two balancing conductive parts along the thickness direction of the acquisition board, and the other end of the balancing resistor is stacked on the other of the two balancing conductive parts along the thickness direction of the acquisition board.

[0014] In combination with the second aspect, in a feasible implementation, there are multiple balancing resistors, and every two adjacent balancing resistors are spaced apart along the length direction of the acquisition board. One ends of the multiple balancing resistors are commonly connected to one of the two balancing conductive parts, and the other ends of the multiple balancing resistors are commonly connected to the other of the two balancing conductive parts.

[0015] In combination with the second aspect, in a feasible implementation manner, the balancing resistor is disposed in a bent region between the two balancing conductive portions.

[0016] In combination with the second aspect, in a feasible implementation manner, the balancing resistor is a film structure, and the thickness of the balancing resistor is 1 μm-100 μm.

[0017] In combination with the second aspect, in a feasible implementation, the acquisition board further includes two insulating protective layers, the two insulating protective layers are arranged at intervals along the thickness direction of the acquisition board, and the balancing resistor and the conductive circuit layer are arranged between the two insulating protective layers. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the background technology, the drawings required for use in the embodiments of the present application or the background technology will be described below.

[0019] Figure 1 A schematic diagram of the structure of an energy storage device provided by the utility model;

[0020] Figure 2 A schematic diagram of the structure of a collection board provided by the utility model;

[0021] Figure 3 A top view of a collection board provided by the utility model with the insulating protective layer omitted;

[0022] Figure 4 A structural block diagram of an energy storage device provided by the utility model;

[0023] Figure 5 A schematic diagram of a structure in which a balancing resistor provided by the utility model is connected to two balancing conductive parts;

[0024] Figure 6 A schematic diagram of another structure of a balancing resistor connected to two balancing conductive parts provided by the utility model;

[0025] Figure 7 This is a structural block diagram of another energy storage device provided by the utility model.

[0026] Description of reference numerals:

[0027] 1100, energy storage device; 1110, battery cell; 1111, positive electrode; 1112, negative electrode; 1120, acquisition board; 1120a, conductive circuit layer; 1121, pressure sampling conductive part; 1122, temperature sampling conductive part; 1123, balancing circuit; 1123a, balancing resistor; 1123b, balancing conductive part; 1124, insulating protective layer; 1130, controller; 1140, pressure sampling processor; 1150, temperature sensing element; 1160, temperature collector; 1170, aluminum bar; 1180, nickel sheet. DETAILED DESCRIPTION

[0028] Energy storage devices play an important role in the process of renewable energy power generation (such as wind power generation, photovoltaic power generation, etc.). By storing and releasing energy, energy storage devices can stabilize the power generation system, provide energy backup, and improve the quality of electricity. They have good application prospects.

[0029] With the development of energy storage devices, the energy density of energy storage devices has received more and more attention. During the charging process of energy storage devices, due to the possible difference in the internal resistance of each battery cell in the energy storage device, some batteries are fully charged while others are not. If charging continues, it is easy to overcharge the fully charged battery cells and damage the energy storage device.

[0030] An equalizing element and a control circuit of the equalizing element are provided in the energy storage device, so that when the energy storage device continues to charge, the fully charged cells will consume electric energy by the equalizing element, and overcharging is not likely to occur. The equalizing element and the control circuit of the equalizing element will occupy a large space of the energy storage device, reducing the energy density of the energy storage device.

[0031] In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings.

[0032] For the convenience of description, the length direction of the acquisition board is defined as the X-axis direction, the width direction of the acquisition board is defined as the Y-axis direction, and the height direction of the acquisition board is defined as the Z-axis direction.

[0033] See also Figure 1 and Figure 2The energy storage device 1100 may be, but is not limited to, a battery or a battery pack. The energy storage device 1100 includes a plurality of battery cells 1110, a collection board 1120, a controller 1130, a pressure collection processor 1140, a temperature sensing element 1150, and a temperature collector 1160. The plurality of battery cells 1110 are connected in series or in parallel. The plurality of battery cells 1110 are arranged in sequence along the length direction of the collection board 1120. The collection board 1120 is disposed on the end faces of the plurality of battery cells 1110. The end face of each battery cell 1110 facing the collection board 1120 is provided with a positive electrode and a negative electrode, and the positive electrode and the negative electrode are electrically connected to the conductive layer circuit layer of the collection board 1120. The collection board 1120 is arranged on the end surface where the positive and negative electrodes of each battery cell 1110 are located, which can facilitate the electrical connection between the conductive circuit layer in the collection board 1120 and each battery cell 1110. There is no need to electrically connect the collection board 1120 and each battery cell 1110 through an intermediate electrical connection device, which saves the space occupied by the intermediate electrical connection device and improves the energy density of the energy storage device.

[0034] The acquisition board 1120 may be a flexible printed circuit (FPC). The acquisition board 1120 includes a conductive circuit layer 1120a and a balancing resistor 1123a stacked along the thickness direction of the acquisition board. The conductive circuit layer is used to electrically connect to each of the multiple battery cells 1110. The balancing resistor is used to discharge the battery cell 1110 when a path is formed between one of the multiple battery cells 1110, the conductive circuit layer 1120a and the balancing resistor 1123a.

[0035] See also Figure 3The conductive circuit layer can be etched to form a pressure-collecting conductive part 1121, and the pressure-collecting processor 1140 can collect the voltage of each battery cell 1110 in the energy storage device 1100 through the pressure-collecting conductive part. Specifically, each battery cell 1110 of the energy storage device 1100 corresponds to two pressure-collecting conductive parts 1121 of the collection board 1120, and the interface of the pressure-collecting processor 1140 is respectively connected to the two pressure-collecting conductive parts 1121, and the two pressure-collecting conductive parts 1121 are respectively connected to the positive electrode 1111 of the battery cell 1110 and the negative electrode 1112 of the battery cell 1110. In this way, the pressure-collecting processor 1140 can collect the voltage of the battery cell 1110. It should be noted that the energy storage device 1100 has a plurality of battery cells 1110. Generally speaking, the voltage of a single battery cell 1110 is relatively low. In order to increase the voltage of the energy storage device 1100, the voltage of the energy storage device 1100 can be increased by connecting a plurality of battery cells 1110 in series. In the present application, at least some of the battery cells 1110 of the energy storage device 1100 are electrically connected in series. If the energy storage device 1100 has battery cells A and B connected in series, and the negative electrode 1112 of battery cell A is connected to the positive electrode 1111 of battery cell B, then the voltage of the positive electrode 1111 of battery cell A and the negative electrode 1112 of battery cell A is equal to the voltage of the positive electrode 1111 of battery cell A and the positive electrode 1111 of battery cell B. The negative electrode 1112 of battery cell A and the positive electrode 1111 of battery cell B can be connected together to a voltage collection conductive portion 1121 of the collection board 1120, so that Optimize the circuit structure of the acquisition board 1120. At this time, the acquisition board 1120 only needs to be provided with three voltage collection conductive parts 1121. The three voltage collection conductive parts 1121 can be marked as the first voltage collection conductive part, the second voltage collection conductive part and the third voltage collection conductive part. The first voltage collection conductive part is connected to the positive electrode 1111 of the A battery cell, the second voltage collection conductive part is connected to the negative electrode 1112 of the A battery cell or the positive electrode 1111 of the B battery cell, and the third voltage collection conductive part is connected to the negative electrode 1112 of the B battery cell. The interface of the voltage collection processor 1140 is connected to the three voltage collection conductive parts 1121, and the voltage of the A battery cell can be collected, and the voltage of the B battery cell can also be collected. If the energy storage device 1100 has three battery cells 1110 connected in series, the acquisition board 1120 uses four corresponding voltage collection conductive parts 1121, which are connected to the interface of the voltage collection processor 1140 to collect the voltages of the three battery cells 1110 connected in series respectively. If the energy storage device 1100 has n battery cells 1110 connected in series, the acquisition board 1120 uses n+1 voltage sampling conductive parts 1121 to connect to the interface of the voltage sampling processor 1140 to respectively collect the voltages of the n battery cells 1110 connected in series, where n≥3.

[0036] In the embodiment provided in the present application, the conductive circuit layer of the collection board 1120 is also etched to form a temperature collecting conductive part 1122, and the temperature collecting conductive part 1122 is connected between the temperature sensing element and the temperature collector 1160. The temperature collecting conductive part 1122 is formed by etching the conductive circuit layer. The temperature collector 1160 can apply voltage and current to the temperature sensing element 1150 through the temperature collecting conductive part 1122. The resistance of the temperature sensing element 1150 will change with the change of temperature. The temperature collector 1160 can obtain the temperature of the temperature sensing element 1150 by calculating the resistance of the temperature sensing element 1150. The temperature sensing element 1150 can be set on the battery cell 1110. The temperature collector 1160 can obtain the temperature of the battery cell 1110 in the energy storage device 1100 in real time by collecting the temperature of the temperature sensing element 1150.

[0037] When the energy storage device 1100 is charged, the battery cells 1110 connected in series in the energy storage device 1100 start charging at the same time and end charging at the same time. Since the internal resistance of the battery cells 1110 connected in series in the energy storage device 1100 is different, the electric energy lost by the heat generated by the battery cells 1110 connected in series is different. This makes some battery cells 1110 fully charged while some battery cells 1110 are not fully charged when charging the battery cells 1110 connected in series. If the fully charged battery cells 1110 are not charged, the fully charged battery cells 1110 are easily overcharged, causing damage to the fully charged battery cells 1110.

[0038] In this application, see Figure 3 The conductive circuit layer of the collection board 1120 also includes a balancing circuit 1123. Each battery cell 1110 of the energy storage device 1100 corresponds to two balancing circuits 1123 of the collection board 1120 that are spaced apart along the length direction of the collection board 1120. The interfaces of the controller 1130 are respectively connected to the two balancing circuits 1123, and the two balancing circuits 1123 are respectively connected to the positive electrode 1111 of the battery cell 1110 and the negative electrode 1112 of the battery cell 1110. The controller 1130 can control the two balancing circuits 1123 to be connected in series.

[0039] The balancing circuit 1123 includes two balancing conductive parts 1123b spaced apart along the width direction of the acquisition board 1120, and the two balancing conductive parts 1123b are connected in series through a balancing resistor 1123a. When the positive electrode 1111 of the battery cell 1110, the negative electrode 1112 of the battery cell 1110 and the two balancing circuits 1123 form a loop, the balancing resistor 1123a can generate heat to consume the electric energy of the battery cell 1110. It should be noted that the balancing resistor 1123a can be a film-mounted structure, and the balancing resistor 1123a includes but is not limited to a carbon film. The material of the balancing resistor 1123a includes one of carbon crystal, carbon fiber or graphene. The carbon film can be composed of materials such as carbon crystal, carbon fiber or graphene. The carbon film has good heating uniformity. When converting electrical energy into thermal energy, the carbon film can generate a large amount of infrared radiation, which is beneficial to the heat dissipation of the balancing resistor. By controlling the thickness and shape of the carbon film, the resistance of the carbon film can also be easily controlled. The thickness of the balancing resistor is 1μm-100μm, which has a large heat dissipation area and good heat dissipation performance. If the balancing resistor exceeds 100μm, the thickness is too large and it is not convenient for the balancing resistor to dissipate heat when powered on. If the balancing resistor is less than 1μm, the thickness is too small and it is difficult to form the balancing resistor.

[0040] Continue to see Figure 2 The acquisition board 1120 also includes two insulating protective layers, and the conductive circuit layer 1120a is enclosed between the two insulating protective layers 1124. Among them, the balancing circuit 1123, the temperature collecting conductive part and the pressure collecting conductive part 1121 are all enclosed between the two insulating protective layers 1124. The upper insulating protective layer 1124 has an insulating protective function and an anti-corrosion protective function. The insulating protective layer is polyimide (PI) or polyethylene terephthalate (PET).

[0041] See also Figure 4In the embodiment provided in the present application, if the energy storage device 1100 has a battery cell A and a battery cell B connected in series, for example, the negative electrode 1112 of the battery cell A is connected to the positive electrode 1111 of the battery cell B, and the negative electrode 1112 of the battery cell A and the positive electrode 1111 of the battery cell B can be connected to a balancing circuit 1123 of the acquisition board 1120. At this time, the acquisition board 1120 only needs to set three balancing circuits 1123, and the three balancing circuits 1123 are respectively marked as balancing circuit No. 1, balancing circuit No. 2, and balancing circuit No. 3. Exemplarily, one end of the balancing circuit No. 1 is connected to the positive electrode 1111 of the battery cell A, and the other end of the balancing circuit No. 1 is connected to the interface of the controller 1130. One end of the balancing circuit No. 2 is connected to the negative electrode 1112 of the battery cell A or the positive electrode 1111 of the battery cell B, and the other end of the balancing circuit No. 2 is connected to the interface of the controller 1130. One end of the No. 3 balancing circuit is connected to the negative electrode 1112 of the B battery cell, and the other end of the No. 3 balancing circuit is connected to the interface of the controller 1130. Assuming that the A battery cell is fully charged during the charging process of the energy storage device 1100, but the B battery cell is not yet fully charged, at this time, in order to fully charge the B battery cell, the energy storage device 1100 needs to continue to be charged. The controller 1130 controls the No. 1 balancing circuit and the No. 2 balancing circuit to be connected in series. The balancing resistor connecting the two balancing conductive parts in the No. 1 balancing circuit can consume the electric energy of the A battery cell, and the balancing resistor connecting the two balancing conductive parts 1123b in the No. 2 balancing circuit can consume the electric energy of the A battery cell, thereby reducing the risk of overcharging of the A battery cell.

[0042] Assume that during the charging process of the energy storage device 1100, the B cell is fully charged, while the A cell is not yet fully charged. At this time, in order to fully charge the A cell, the energy storage device 1100 needs to continue to be charged. The controller 1130 controls the No. 2 balancing circuit and the No. 3 balancing circuit to be connected in series. The balancing resistor 1123a connected to the two balancing conductive parts 1123b in the No. 2 balancing circuit can consume the electric energy of the B cell, or the balancing resistor connected to the two balancing conductive parts in the No. 3 balancing circuit can consume the electric energy of the B cell and release heat energy to reduce the risk of overcharging of the B cell. If the energy storage device 1100 has three cells 1110 connected in series, the acquisition board 1120 uses four balancing circuits 1123 correspondingly, and the four balancing circuits 1123 are connected to the interface of the controller 1130. If the energy storage device 1100 has n cells 1110 connected in series, the acquisition board 1120 uses n+1 balancing circuits 1123 correspondingly to be connected to the interface of the balancing control, and n≥3. When the energy storage device 1100 is being charged, some of the cells 1110 are fully charged, while some of the cells 1110 are not fully charged. The controller 1130 controls the positive and negative poles of the fully charged cells 1110 to form a loop with the balancing resistor to consume the electric energy of the fully charged cells 1110, thereby reducing the risk of overcharging of the fully charged cells 1110 in the energy storage device 1100. The balancing resistor is integrated in the acquisition board 1120, and the acquisition board 1120 can balance the excess electric energy of the cells 1110 in the energy storage device 1100, saving the space occupied by the balancing components in the energy storage device 1100 and reducing the cost of the energy storage device 1100.

[0043] In the embodiment provided in the present application, an aluminum bar 1170 is led out from the positive electrode 1111 of each battery cell 1110 of the energy storage device 1100, and the positive electrode 1111 of the battery cell 1110 is conveniently connected to the balancing circuit 1123 or the voltage-collecting conductive part 1121 through the aluminum bar 1170. An aluminum bar 1170 is led out from the negative electrode 1112 of each battery cell 1110 of the energy storage device 1100, and the negative electrode 1112 of the battery cell 1110 is conveniently connected to the balancing conductive part or the voltage-collecting conductive part 1121 in the balancing circuit 1123 through the aluminum bar 1170.

[0044] In the embodiment provided in the present application, after the aluminum bar 1170 is led out from the positive electrode 1111 of each battery cell 1110 of the energy storage device 1100, a nickel sheet 1180 is connected in series on the aluminum bar 1170, and then connected to the balancing conductive part or the pressure-collecting conductive part 1121 in the balancing circuit 1123 through the nickel sheet 1180. After the aluminum bar 1170 is led out from the negative electrode 1112 of each battery cell 1110 of the energy storage device 1100, a nickel sheet 1180 is connected in series on the aluminum bar 1170, and then connected to the balancing conductive part or the pressure-collecting conductive part 1121 in the balancing circuit 1123 through the nickel sheet 1180. The nickel sheet 1180 has high corrosion resistance, strong plasticity and is easy to tin. The nickel sheet 1180 is used as the positive electrode 1111 connecting sheet of the battery cell 1110 or the negative electrode 1112 connecting sheet of the battery cell 1110, which can improve the service life of the energy storage device 1100 and facilitate the installation and molding of the energy storage device 1100.

[0045] In the examples provided in this application, see Figure 5 The conductive circuit layer is composed of materials such as copper or aluminum. When etching is performed on the conductive circuit layer to form a balancing circuit, at least two spaced balancing conductive parts 1123b are etched on the conductive circuit layer. The balancing resistor is directly printed on the at least two balancing conductive parts 1123b through a printing process, and the two ends of the balancing resistor along the width direction of the acquisition board are respectively stacked on the two balancing conductive parts 1123b. The balancing resistor can also be printed on the inner surface of the insulating protective layer. When the insulating protective layer is in contact with the conductive circuit layer, the two ends of the balancing resistor along the width direction of the acquisition board are respectively in contact with the two balancing conductive parts, and the balancing resistor connects at least two balancing conductive parts 1123b in series. In this way, the balancing resistor can be easily integrated into the acquisition board, which simplifies the manufacturing process of the acquisition board and can also reduce the space occupied by the balancing resistor. It should be noted that, please refer to Figure 4When the acquisition board 1120 is applied to the energy storage device 1100, if the pressure sampling processor 1140 collects through the acquisition board 1120 that the A battery cell of the energy storage device 1100 is full, the pressure sampling processor 1140 can send a balancing signal to the controller 1130, and the controller 1130 can control the balancing line 1123 connected to the positive electrode 1111 of the A battery cell and the balancing line 1123 connected to the negative electrode 1112 of the A battery cell to be turned on. At this time, the balancing resistor in the acquisition board can consume the electric energy of the A battery cell, wherein the balancing resistor of the balancing line 1123 can convert the electric energy of the A battery cell into heat energy. The balancing resistor is a film-like structure with a large heat dissipation area. After converting the electric energy of the A battery cell into heat energy, it can quickly dissipate heat. It should be noted that the controller 1130 may include but is not limited to a field effect transistor (MOS tube). Taking the controller 1130 including a field effect transistor as an example, the interface of the controller 1130 is connected to the balancing circuit 1123 connected to the positive electrode 1111 of the A battery cell and the balancing circuit 1123 connected to the negative electrode 1112 of the A battery cell in the acquisition board 1120. When the field effect transistor is turned on, the balancing circuit 1123 connected to the positive electrode 1111 of the A battery cell and the balancing circuit 1123 connected to the negative electrode 1112 of the A battery cell are turned on, so that the balancing resistor consumes the electric energy of the A battery cell. When the field effect transistor is turned off, the balancing circuit 1123 connected to the positive electrode 1111 of the A battery cell and the balancing circuit 1123 connected to the negative electrode 1112 of the A battery cell are disconnected electrically.

[0046] In the embodiment provided in the present application, the cross section of the balancing resistor 1123a along the thickness direction may be, but is not limited to, a rectangle.

[0047] In one possible implementation, see Figure 5 The balancing resistor can be bent, one end of the balancing resistor is connected to a balancing conductive part 1123b in the balancing line 1123, the other end of the balancing resistor is connected to another balancing conductive part 1123b in the balancing line 1123, and the balancing resistor is bent in the area between the two balancing conductive parts 1123b. Specifically, the balancing resistor is roughly S-shaped, and when the balancing resistor is controlled to have a larger resistance value, the heat dissipation area of ​​the balancing resistor is increased, and the heat dissipation efficiency of the acquisition board 1120 is improved.

[0048] In one possible implementation, see Figure 6, two balancing conductive parts in the balancing circuit can be connected through multiple balancing resistors, and there is a spacing between every two adjacent balancing resistors along the length direction of the acquisition board, one end of the multiple balancing resistors is commonly connected to a balancing conductive part 1123b of the balancing circuit 1123, and the other end of the multiple balancing resistors is commonly connected to another balancing conductive part 1123b of the balancing circuit 1123. Multiple balancing resistors are arranged in parallel, so that the total resistance of the multiple balancing resistors 1123a connected in series with the two balancing conductive parts 1123b remains small, and the heat dissipation surface of the multiple balancing resistors 1123a in the balancing circuit 1123 is increased, which is conducive to improving the heat dissipation capacity of the balancing resistors.

[0049] The following is a technical solution for connecting each equalizing line with the corresponding voltage collecting and conducting part in series. Figure 7 ,and Figure 3 The difference between the energy storage device 1100 and the energy storage device 1100 is that the energy storage device 1100 no longer has a voltage sampling processor to collect the voltage of the battery cells in the energy storage device. The voltage of each battery cell 1110 in the energy storage device 1100 is collected through the controller 1130. The controller 1130 can also balance the excess electrical energy for each battery cell 1110 of the energy storage device 1100.

[0050] For ease of understanding, the present application takes the energy storage device 1100 having a battery cell A and a battery cell B connected in series as an example, and the negative electrode 1112 of the battery cell A is connected to the positive electrode 1111 of the battery cell B. The acquisition board 1120 has a No. 1 balancing resistor 1123a, a No. 2 balancing resistor 1123a, a No. 3 balancing resistor 1123a, a No. 1 voltage collecting conductive part 1121, a No. 2 voltage collecting conductive part 1121, and a No. 3 voltage collecting conductive part 1121. One end of the No. 1 balancing resistor 1123a is connected to the positive electrode 1111 of the battery cell A, and the other end of the No. 1 balancing resistor 1123a is connected in series with the No. 1 voltage collecting conductive part. One end of the No. 2 balancing resistor 1123a is connected to the negative electrode 1112 of the battery cell A or the positive electrode 1111 of the battery cell B, and the other end of the No. 2 balancing resistor 1123a is connected in series with the No. 2 voltage collecting conductive part. One end of the No. 3 balancing resistor 1123a is connected to the negative electrode 1112 of the B battery cell, and the other end of the No. 3 balancing resistor 1123a is connected in series with the No. 3 voltage collecting conductive part. The No. 1 voltage collecting conductive part, the No. 2 voltage collecting conductive part and the No. 3 voltage collecting conductive part 1121 are connected to the interface of the controller 1130. The controller 1130 forms a loop with the positive electrode 1111 of the A battery cell and the negative electrode 1112 of the A battery cell (the positive electrode 1111 of the B battery cell) to collect the voltage of the A battery cell, wherein the positive electrode 1111 of the A battery cell is connected to the interface of the controller 1130 through the No. 1 balancing resistor 1123a and the No. 1 voltage collecting conductive part 1121, and the negative electrode 1112 of the A battery cell is connected to the interface of the controller 1130 through the No. 2 balancing resistor 1123a and the No. 2 voltage collecting conductive part. The controller 1130 can form a loop with the positive electrode 1111 of the B battery cell (the negative electrode 1112 of the A battery cell) and the negative electrode 1112 of the B battery cell to collect the voltage of the B battery cell, wherein the positive electrode 1111 of the B battery cell is connected to the interface of the controller 1130 through the No. 2 balancing resistor 1123a and the No. 2 voltage-collecting conductive part, and the negative electrode 1112 of the B battery cell is connected to the interface of the controller 1130 through the No. 3 balancing resistor 1123a and the No. 3 voltage-collecting conductive part.

[0051] If the voltage of cell A collected by controller 1130 has reached the rated voltage value, while the voltage of cell B has not yet reached the rated voltage value, cell B still needs to continue charging. In order to prevent cell A from being overcharged, controller 1130 can control the No. 1 voltage collecting conductive part 1121 and the No. 2 voltage collecting conductive part 1121 to be turned on, and the No. 1 balancing resistor 1123a and the No. 2 balancing resistor 1123a can generate heat to consume the electric energy of cell A. If the voltage of cell B collected by controller 1130 has reached the rated voltage value, while the voltage of cell A has not yet reached the rated voltage value, cell A still needs to continue charging. In order to prevent cell B from being overcharged, controller 1130 can control the No. 2 voltage collecting conductive part 1121 and the No. 3 voltage collecting conductive part 1121 to be turned on, and the No. 2 balancing resistor 1123a and the No. 3 balancing resistor 1123a can generate heat to consume the electric energy of cell B.

[0052] When each balancing resistor 1123a is connected in series with the corresponding voltage collecting conductive part 1121, the resistance of the balancing resistor 1123a should not be too large. If the resistance of the balancing resistor 1123a is too large, the voltage of each battery cell 1110 in the energy storage device 1100 collected by the controller 1130 will be inaccurate. When each balancing resistor 1123a is connected in series with the corresponding voltage collecting conductive part 1121, each balancing resistor 1123a can be provided with multiple balancing resistors 1123a, and the accuracy of the controller collecting the battery cell voltage is reduced by connecting multiple balancing resistors 1123a in parallel to reduce the resistance of the balancing resistor 1123a. It should be noted that the controller 1130 integrates the function of collecting each battery cell 1110 of the energy storage device 1100, and the controller 1130 can also control the fully charged battery cell 1110 to release electric energy through the balancing resistor to reduce the risk of overcharging of the battery cell 1110 in the energy storage device 1100.

[0053] The first, second, third, fourth and various numerical numbers involved in this document are only distinguished for the convenience of description and are not intended to limit the scope of the present application.

[0054] It should be understood that in the various embodiments of the present application, the size of the serial numbers of the above-mentioned processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0055] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, a person skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application.

Claims

1. An energy storage device, characterized in that: It comprises a plurality of battery cells and a collection board, wherein the collection board comprises a conductive circuit layer and a balancing resistor stacked along the thickness direction of the collection board, the conductive circuit layer is used to be electrically connected to each of the plurality of battery cells, and the balancing resistor is used to discharge a battery cell among the plurality of battery cells when a path is formed between the conductive circuit layer and the balancing resistor.

2. The energy storage device according to claim 1, characterized in that The conductive circuit layer includes two balancing conductive parts spaced apart along the width direction of the acquisition board, one end of the balancing resistor is stacked on one of the two balancing conductive parts, and the other end of the balancing resistor is stacked on the other of the two balancing conductive parts, and any one of the two balancing conductive parts is electrically connected to a battery cell.

3. The energy storage device according to claim 2, characterized in that: There are multiple balancing resistors, and every two adjacent balancing resistors are spaced apart along the length direction of the acquisition board. One ends of the multiple balancing resistors are commonly connected to one of the two balancing conductive parts, and the other ends of the multiple balancing resistors are commonly connected to the other of the two balancing conductive parts.

4. The energy storage device according to claim 2, characterized in that: The balancing resistor is disposed in a bent area between the two balancing conductive parts.

5. The energy storage device according to any one of claims 1 to 4, characterized in that: The balancing resistor is a film structure, and the thickness of the balancing resistor is 1 μm-100 μm.

6. The energy storage device according to any one of claims 1 to 4, characterized in that: The acquisition board also includes two insulating protective layers, which are arranged at intervals along the thickness direction of the acquisition board, and the balancing resistor and the conductive circuit layer are arranged between the two insulating protective layers.

7. The energy storage device according to claim 1, characterized in that: The multiple battery cells are arranged in sequence along the length direction of the collection board, and the collection board is arranged on the end surfaces of the multiple battery cells. The end surface of each battery cell facing the collection board is provided with a positive electrode and a negative electrode, and the positive electrode and the negative electrode are electrically connected to the conductive layer circuit layer of the collection board.

8. The energy storage device according to claim 1, characterized in that: The energy storage device further includes a controller, which is electrically connected to the conductive circuit layer, and is used to control one of the multiple battery cells, the conductive circuit layer, and the balancing resistor to form a path.

9. A collection board, characterized in that: The acquisition board includes a conductive circuit layer and a balancing resistor, and the balancing resistor is stacked on the conductive circuit layer along the thickness direction of the acquisition board.

10. The acquisition board according to claim 9, characterized in that: The conductive circuit layer has two balancing conductive parts, and the two balancing conductive parts are arranged at intervals along the width direction of the acquisition board. One end of the balancing resistor is stacked on one of the two balancing conductive parts along the thickness direction of the acquisition board, and the other end of the balancing resistor is stacked on the other of the two balancing conductive parts along the thickness direction of the acquisition board.

11. The acquisition board according to claim 10, characterized in that: There are multiple balancing resistors, and every two adjacent balancing resistors are spaced apart along the length direction of the acquisition board. One ends of the multiple balancing resistors are commonly connected to one of the two balancing conductive parts, and the other ends of the multiple balancing resistors are commonly connected to the other of the two balancing conductive parts.

12. The acquisition board according to claim 10, characterized in that: The balancing resistor is disposed in a bent area between the two balancing conductive parts.

13. The acquisition board according to any one of claims 9 to 12, characterized in that: The balancing resistor is a film structure, and the thickness of the balancing resistor is 1 μm-100 μm.

14. The acquisition board according to any one of claims 9 to 12, characterized in that: The acquisition board also includes two insulating protective layers, which are arranged at intervals along the thickness direction of the acquisition board, and the balancing resistor and the conductive circuit layer are arranged between the two insulating protective layers.

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