Battery pack

Abstract

The application relates to the battery technical field, in particular to a battery pack, which comprises a battery cell assembly, two end plates, two clamping plates and a heating plate; wherein the battery cell assembly comprises a plurality of battery cells which are sequentially stacked together along a first preset direction, and along the first preset direction, the two end plates are arranged at the two ends of the battery cell assembly respectively; along a second preset direction, the two clamping plates are arranged at the opposite sides of the battery cell assembly respectively, and the clamping plates are connected with the two end plates; and at least one clamping plate is provided with the heating plate between the clamping plate and the battery cell assembly. It can be seen that the heating plate is added on the basis of the existing structure, the heating plate is started in a low-temperature environment, the battery cell is preheated, the battery cell reaches a suitable charging and discharging use temperature, and then the battery cell is used, so that the charging and discharging efficiency of the battery pack is guaranteed, and the service life of the battery pack is prolonged; in addition, the end plates and the clamping plates are arranged for the battery cell assembly in the application, the size of the battery cell assembly is constrained, and a certain pre-tightening force can be pre-applied to the battery cell assembly.

Description

Technical Field

[0001] This application relates to the field of battery technology, and in particular to a battery pack. Background Technology

[0002] In low-temperature environments (especially below -20°C), the performance of traditional lithium-ion batteries degrades significantly, severely restricting the application of related technologies in cold regions and special scenarios. Low temperatures lead to deterioration in electrolyte kinetics, hindered interfacial reactions, and reduced self-heating capacity of cells in low-temperature environments, resulting in a significant decrease in cell or battery pack capacity retention and charge / discharge efficiency. Application environments or regions such as polar workstations, deep-sea probes, and electric logistics vehicles in northern regions face severe winter range reduction issues. Therefore, developing battery packs with excellent low-temperature performance has become a key direction for breaking through the bottlenecks of new energy technologies and expanding application boundaries. Utility Model Content

[0003] The purpose of this application is to provide a battery pack that, to a certain extent, solves the technical problem of the urgent need to develop battery packs with excellent low-temperature performance in the prior art.

[0004] This application provides a battery pack, including: a cell assembly, two end plates, two clamping plates, and a heating plate; wherein, the cell assembly includes a plurality of cells stacked sequentially along a first preset direction, and the two end plates are respectively disposed at both ends of the cell assembly along the first preset direction;

[0005] Along the second preset direction, the two clamping plates are respectively disposed on opposite sides of the battery cell assembly, and each clamping plate is connected to the two end plates respectively; at least one clamping plate is provided with a heating plate between it and the battery cell assembly.

[0006] In the above technical solution, the battery pack further includes a heat insulation layer, which is disposed between the heating plate and the clamping plate.

[0007] In any of the above technical solutions, the heating plate is further connected to the side of the battery cell assembly via thermally conductive adhesive.

[0008] In any of the above technical solutions, the battery pack further includes a sampling circuit board and a conductive component; wherein, along the height direction of the battery cell, the sampling circuit board is disposed on the top of the battery cell assembly, and the conductive component is disposed on the side of the sampling circuit board opposite to the battery cell assembly and connected to the circuit board;

[0009] The sampling circuit board has multiple through holes, and the positive and negative tabs of any two adjacent cells pass through the corresponding through holes, bend, and overlap. The positive tab, the negative tab, and the conductive component are welded together.

[0010] In any of the above technical solutions, the battery pack further includes a total positive lead and a total negative lead disposed on the circuit board. Along the first preset direction, the positive tab of one of the first and last cells passes through the corresponding through hole and bends on the total positive lead, and is connected to the total positive lead by welding. The negative tab of the other cell passes through the corresponding through hole and bends on the total negative lead, and is connected to the total negative lead by welding.

[0011] In any of the above technical solutions, the battery pack further includes a battery management module, which is disposed on the side of one of the end plates opposite to the cell assembly; the total negative lead is electrically connected to the battery management module.

[0012] The battery pack also includes a total positive electrode and a total negative electrode. The total positive electrode is electrically connected to the total positive lead-out; the total negative electrode is electrically connected to the battery management module; and the heating plate is electrically connected to the battery management module.

[0013] In any of the above technical solutions, the battery pack further includes a connector disposed on the circuit board, and the connector is disposed close to the battery management module along the first preset direction; the connector is electrically connected to the battery management module.

[0014] In any of the above technical solutions, the battery pack further includes an insulating sheet, which is disposed on the side of the circuit board away from the cell assembly, and the insulating sheet covers the outside of the positive electrode tab and the negative electrode tab;

[0015] The battery pack also includes tab foam, which covers the outside of the insulating sheet.

[0016] In any of the above technical solutions, the end plate further includes a flat plate portion and a U-shaped reinforcing plate portion; wherein, there are multiple flat plate portions and U-shaped reinforcing plate portions, which are alternately arranged and connected along the height direction of the battery cell, and the flat plate portions are located at the top and bottom positions; the opening of the U-shaped reinforcing plate portion is arranged facing the battery cell assembly side.

[0017] In any of the above technical solutions, the clamping plate further includes a main body and an L-shaped bend portion connected to it; wherein, along the first preset direction, the L-shaped bend portion is disposed at one end of the main body, and the L-shaped bend portion cooperates with the U-shaped reinforcing plate portion, and is detachably connected by a fastening member.

[0018] In any of the above technical solutions, a buffer layer is further provided between any two adjacent battery cells.

[0019] In any of the above technical solutions, a buffer layer is further provided between the battery cell assembly and the end plate.

[0020] In any of the above technical solutions, the battery pack further includes multiple heat insulation layers, and the multiple heat insulation layers are sequentially inserted inside the cell assembly.

[0021] In any of the above technical solutions, further, along the second preset direction, the projection of the heating plate falls into the projection of the battery cell assembly, and there is a gap C between the projection edges of the two, and 0.2t≤C≤0.6t, where t is the thickness of the battery cell along the first preset direction.

[0022] In any of the above technical solutions, the heating plate is further disposed centered on the side of the battery cell assembly.

[0023] In any of the above technical solutions, the battery pack further includes a housing, and the cell assembly, the two end plates, the two clamping plates and the heating plate are all disposed inside the housing, and the interior of the housing is filled with thermally conductive adhesive.

[0024] In any of the above technical solutions, the battery pack further includes a bottom foam, and the bottom foam is adhered to the bottom of the battery cell assembly along the height direction of the cell.

[0025] Compared with the prior art, the beneficial effects of this application are as follows:

[0026] This application provides a low-temperature heated battery pack. Based on the existing structure, a heating plate is added, which activates in low-temperature environments to preheat the battery cells, ensuring they reach suitable charge / discharge operating temperatures before use. This guarantees the battery pack's charge / discharge efficiency and extends its lifespan. Furthermore, this application includes end plates and clamps for the battery cell assembly, constraining its dimensions and applying a pre-tightening force to suppress expansion and extend cycle life. The application also limits the heating plate's dimensions and fixes its position relative to the side of the battery cell assembly, ensuring the heating heat covers all cells and that each cell is heated simultaneously in low-temperature environments.

[0027] In addition, this application eliminates the tab bracket and directly uses a circuit board as the support for the tab. The tab passes through the through hole on the circuit board and bends onto the conductive component. The positive tab, negative tab and conductive component are directly welded together, saving process steps and the investment of parts, which greatly reduces costs. Moreover, the circuit board is connected to the tab, so the sampling circuit board can collect data such as the voltage of the battery cell.

[0028] In addition, a battery management module is provided. Through the reasonable arrangement and connection between the battery management module, the total negative lead on the circuit board, and the heating plate, the external charging device can fully heat the heating plate in the initial stage, thereby quickly heating the battery cell to the charging temperature. In the middle stage, the charging device provides power to the heating plate to heat the battery cell, while the charging device charges the battery cell. This allows the battery cell to charge slowly, thus avoiding the lithium plating effect caused by high current charging. It also helps to reduce the impact of low temperature charging on battery cell degradation, thereby improving the battery pack's lifespan. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the specific embodiments of this application or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0030] Figure 1 An exploded view of the battery pack provided in an embodiment of this application;

[0031] Figure 2 Another exploded view of the battery pack provided in the embodiments of this application;

[0032] Figure 3 This is a schematic diagram of the sampling circuit board provided in an embodiment of this application;

[0033] Figure 4 An assembly diagram of the battery pack provided for an embodiment of this application (the outer casing is not shown in the figure);

[0034] Figure 5 This is a schematic diagram of the end plate provided in an embodiment of this application;

[0035] Figure 6 This is a schematic diagram of the structure of the clamp provided in the embodiment of this application;

[0036] Figure 7 This is a schematic diagram of the battery cell structure provided in an embodiment of this application;

[0037] Figure 8This is a schematic diagram of the structure of the battery cell assembly provided in the embodiments of this application;

[0038] Figure 9 This is a schematic diagram showing the electrical connections between the battery management module, the battery cell assembly, and the heating plate provided in an embodiment of this application.

[0039] Figure label:

[0040] 1-Battery cell assembly, 101-Battery cell, 2-End plate, 21-Flat plate section, 22-U-shaped reinforcing section, 3-Clamping plate, 31-Main body, 32-L-shaped bending section, 4-Heating plate, 5-Insulation layer, 6-Sampling circuit board, 61-Through hole, 7-Conductive component, 8-Total positive lead-out, 9-Total negative lead-out, 10-Battery management module, 11-Total positive electrode, 12-Total negative electrode, 13-Connector, 14-Insulating sheet, 15-Electrode foam, 16-Fastening component, 17-Buffer layer, 18-Heat insulation layer, 19-Bottom foam, 20-Thermal conductive adhesive, a-First preset direction, b-Second preset direction. Detailed Implementation

[0041] The technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of this application, but not all embodiments.

[0042] The components of the embodiments of this application described and shown in the accompanying drawings can typically be arranged and designed in a variety of different configurations. Therefore, the following detailed description of the embodiments of this application provided in the drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application.

[0043] Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0044] In the description of this application, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0045] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0046] The following reference Figures 1 to 9 This application describes a battery pack according to some embodiments.

[0047] See Figures 1 to 6 As shown, an embodiment of this application provides a battery pack, including: a cell assembly 1, two end plates 2, two clamping plates 3, and a heating plate 4; wherein, the cell assembly 1 includes a plurality of cells 101 stacked sequentially along a first preset direction a, and the two end plates 2 are respectively disposed at both ends of the cell assembly 1 along the first preset direction a.

[0048] Along the second preset direction b, two clamping plates 3 are respectively disposed on opposite sides of the battery cell assembly 1, and each clamping plate 3 is connected to two end plates 2 respectively; at least one clamping plate 3 is provided with a heating plate 4 between it and the battery cell assembly 1.

[0049] As can be seen from the structure described above, this application provides a low-temperature heating battery pack. By adding a heating plate 4 to the existing structure, the heating plate 4 can be activated in a low-temperature environment to preheat the battery cell 101, so that the battery cell 101 reaches a suitable charging and discharging operating temperature before use. This ensures the charging and discharging efficiency of the battery pack and extends its service life. In addition, this application provides an end plate 2 and a clamping plate 3 for the battery cell assembly 1 to constrain the size of the battery cell assembly 1. At the same time, a certain pre-tightening force can be applied to the battery cell assembly 1, which can suppress expansion to a certain extent and extend the cycle life.

[0050] Furthermore, preferably, the first preset direction a is the thickness direction of the battery cell 101; the second preset direction b is the length direction of the battery cell 101. Of course, it is not limited to this and can be selected according to actual needs.

[0051] In this embodiment, preferably, as follows: Figure 1 As shown, the battery pack also includes an insulation layer 5, which is disposed between the heating plate 4 and the clamping plate 3.

[0052] As can be seen from the structure described above, in a low-temperature environment, when the heating plate 4 heats the battery cell assembly 1, the insulation layer 5 can play a role in heat preservation, preventing excessive heat loss and helping to improve the charging and discharging efficiency of the battery pack.

[0053] In this embodiment, preferably, as follows: Figure 1 As shown, the heating plate 4 is connected to the side of the battery cell assembly 1 via thermally conductive adhesive 20.

[0054] As can be seen from the structure described above, the thermally conductive adhesive 20 can not only fix the heating plate 4, but also conduct the heat of the heating plate 4 to the battery cell 101.

[0055] In this embodiment, preferably, as follows: Figure 2 and Figure 3 As shown, the battery pack also includes a sampling circuit board 6 and a conductive member 7; wherein, the sampling circuit board 6 is disposed on the top of the cell assembly 1 along its height direction, and the conductive member 7 is disposed on the side of the sampling circuit board 6 opposite to the cell assembly 1 and connected to the circuit board.

[0056] The sampling circuit board 6 has multiple through holes 61, and the positive and negative tabs of any two adjacent cells 101 pass through the corresponding through holes 61, bend and overlap together, and the positive tab, negative tab and conductive component 7 are welded together.

[0057] As can be seen from the structure described above, this application eliminates the tab bracket and directly uses a circuit board as the support for the tab. The tab passes through the through hole 61 on the circuit board and bends onto the conductive component 7, directly welding the positive tab, negative tab, and conductive component 7 together. This saves process steps and component investment, greatly reducing costs. Moreover, the circuit board is connected to the tab, so the sampling circuit board 6 can collect data such as the voltage of the battery cell 101.

[0058] Furthermore, preferably, the conductive component 7 is a rectangular metal sheet, and preferably a nickel sheet or an aluminum sheet. Of course, it is not limited to this, and can be selected according to actual needs.

[0059] In this embodiment, preferably, as follows: Figure 3 As shown, the battery pack also includes a total positive lead-out 8 and a total negative lead-out 9 disposed on the circuit board. Along the first preset direction a, the positive electrode tab of one of the first cell 101 and the last cell 101 passes through the corresponding through hole 61 and bends on the total positive lead-out 8, and is connected to the total positive lead-out 8 by welding. The negative electrode tab of the other cell passes through the corresponding through hole 61 and bends on the total negative lead-out 9, and is connected to the total negative lead-out 9 by welding.

[0060] As can be seen from the structure described above, the positive lead-out bar 8 and the negative lead-out bar 9 are used as the energy output terminals of the battery cell assembly 1.

[0061] Furthermore, preferably, the positive lead-out 8 and the negative lead-out 9 can be connected to the circuit board by soldering, but of course, this is not the only option.

[0062] In this embodiment, preferably, as follows: Figure 1 , Figure 4 and Figure 9 As shown, the battery pack also includes a battery management module 10, which is located on one side of one of the end plates 2 away from the cell assembly 1; the total negative lead-out 9 is electrically connected to the battery management module 10.

[0063] The battery pack also includes a total positive electrode 11 and a total negative electrode 12. The total positive electrode 11 is electrically connected to the total positive lead 8, and the total positive electrode 11 and the total negative electrode 12 are used to connect to an external charging device of the battery pack. The total negative electrode 12 is electrically connected to the battery management module 10. The heating plate 4 is electrically connected to the battery management module 10.

[0064] Based on the structure described above, when the temperature of cell 101 is T≤A℃, the external charging device heats only the heating plate 4 through the battery management module 10; when the temperature of cell 101 is A℃<T≤B℃, a portion of the energy of the charging device, i.e., x%, is provided to the heating plate 4, and another portion, i.e., (1-x%)%, is directly provided to the cell assembly 1 for charging; when the temperature of cell 101 is T>B℃, the energy of the charging device is entirely used for charging cell 101. It is evident that in the entire process, initially the external charging device completely heats the heating plate 4, thereby rapidly heating cell 101 to the charging temperature. In the middle stage, the charging device simultaneously provides power to the heating plate 4 to heat cell 101 and charges cell 101, allowing cell 101 to charge slowly. This avoids the lithium plating effect caused by high-current charging on cell 101, helps reduce the degradation effect of low-temperature charging on cell 101, and thus improves the lifespan of the battery pack.

[0065] Further, preferably, -10≤A≤5; 10≤B≤20; 30≤x≤70.

[0066] In this embodiment, preferably, as follows: Figures 1 to 3 As shown, the battery pack also includes a connector 13 disposed on the circuit board, and along the first preset direction a, the connector 13 is disposed near the end of the circuit board and near the battery management module 10; the connector 13 is electrically connected to the battery management module 10.

[0067] As can be seen from the structure described above, the voltage and other data collected by the sampling circuit board 6 can be transmitted to the battery management module 10 through the connector 13. Moreover, the connector 13 is set close to the battery management module 10, which is a convenient setting, saving cable length, effectively avoiding wire harness mess, and helping to reduce material costs.

[0068] Furthermore, preferably, the battery pack also includes a cable and auxiliary connectors 13 connected to both ends of the cable, wherein one of the auxiliary connectors 13 mates with the connector 13 of the battery management module 10, and the other auxiliary connector 13 mates with the connector 13 on the circuit board. Of course, it is not limited to this.

[0069] In this embodiment, preferably, as follows: Figure 1 As shown, the battery pack also includes an insulating sheet 14, which is disposed on the side of the circuit board away from the cell assembly 1, and covers the outside of the positive and negative tabs.

[0070] As can be seen from the structure described above, the insulating sheet 14 serves to insulate and protect the positive and negative electrodes, preventing short circuits and making the system safer and more reliable.

[0071] Furthermore, preferably, the battery pack also includes tab foam 15, which covers the outside of the insulating sheet 14 and plays a role in buffering and shock absorption, thereby protecting the tab and the insulating sheet 14.

[0072] In this embodiment, preferably, as follows: Figure 5 As shown, the end plate 2 includes a flat plate portion 21 and a U-shaped reinforcing plate portion; wherein, there are multiple flat plate portions 21 and U-shaped reinforcing plate portions, and they are alternately arranged and connected along the height of the cell 101, and the top and bottom positions are both flat plate portions 21, that is, one flat plate portion 21, one U-shaped reinforcing plate portion, one flat plate portion 21, one U-shaped reinforcing plate portion... one flat plate portion 21, one U-shaped reinforcing plate portion; the opening of the U-shaped reinforcing plate portion is arranged facing the cell assembly 1 side.

[0073] As can be seen from the structure described above, this application has redesigned the previously heavy end plate 2. The end plate 2 adopts a thin plate structure, and by setting a U-shaped reinforcing plate between adjacent flat plate portions 21, it can increase the strength. In other words, while reducing the thickness, it can also meet the strength requirements, which helps to reduce costs.

[0074] Furthermore, preferably, in this embodiment there are three flat plate portions 21 and two U-shaped reinforcing plate portions. Of course, it is not limited to this and can be selected according to actual needs.

[0075] Furthermore, preferably, the flat plate portion 21 and the U-shaped reinforcing plate portion are an integral structure, with high overall strength and not easily damaged. Preferably, it can be formed by bending, etc., which makes the operation simple and convenient.

[0076] In this embodiment, preferably, as follows: Figure 4 and Figure 6As shown, the clamp 3 includes a main body 31 connected to the clamp and an L-shaped bend 32; wherein, along the first preset direction a, the L-shaped bend 32 is disposed at one end of the main body 31, and the L-shaped bend 32 cooperates with the U-shaped reinforcing part 22, and is detachably connected by fastening members 16 such as screws or bolts.

[0077] As can be seen from the structure described above, the main board 31 covers the side of the battery cell assembly 1 and serves to fix the battery cell assembly 1; the L-shaped bend 32 on the side of the main board 31 serves to turn and cooperate with the U-shaped reinforcing part 22, thereby fixing the clamping plate 3 and the end plate 2 together, constraining the size of the battery module, and applying a certain pre-tightening force to the battery cell assembly 1. Moreover, the clamping plate 3 and the end plate 2 adopt a detachable connection method, which is convenient for installation, disassembly and maintenance.

[0078] Furthermore, preferably, the main body 31 and the L-shaped bending part 32 are an integral structure with high overall strength and are not easily damaged. Preferably, they can be formed by bending, etc., which makes the operation simple and convenient.

[0079] In this embodiment, preferably, as follows: Figure 2 As shown, a buffer layer 17 is provided between any two adjacent battery cells 101, which can absorb the volume expansion of the battery cell 101 during charging and discharging, and avoid structural damage or internal short circuits and damage to the constraint structure caused by excessive compression of the battery cell 101.

[0080] Furthermore, preferably, the material of the buffer layer 17 is foam.

[0081] In this embodiment, preferably, as follows: Figure 2 As shown, a buffer layer 17 is provided between the battery cell assembly 1 and the end plate 2, which serves to buffer and reduce shock.

[0082] Furthermore, preferably, the material of the buffer layer 17 is foam.

[0083] In this embodiment, preferably, as follows: Figure 2 As shown, the battery pack also includes multiple heat insulation layers 18, which are sequentially inserted inside the cell assembly 1.

[0084] As can be seen from the structure described above, the heat insulation layer 18 is inserted inside the cell assembly 1 mainly to prevent the heat from being transferred to adjacent cells 101 when a cell 101 experiences thermal runaway, which could lead to thermal runaway in other cells 101 as well. In other words, the heat insulation layer 18 between cells 101 can block the energy when thermal runaway occurs, prevent further thermal runaway, and improve the safety of the battery pack.

[0085] Furthermore, preferably, a heat insulation layer 18 is placed between every four battery cells 101. Of course, this is not the only option; other options may be selected as needed.

[0086] Furthermore, preferably, the material of the heat insulation layer 18 can be aerogel. Of course, it is not limited to this and can be selected according to actual needs.

[0087] In this embodiment, preferably, as follows: Figure 7 and Figure 8 As shown, along the second preset direction b, the projection of the heating plate 4 falls into the projection of the battery cell assembly 1, and there is a gap C between the edges of the projections of the two, and 0.2t≤C≤0.6t, where t is the thickness of the battery cell 101 along the first preset direction a.

[0088] As can be seen from the structure described above, if the heating plate 4 is too small, it will not be able to heat the battery cell 101 over a large area, thus failing to improve the low-temperature performance of the battery cell 101. If the heating plate 4 is too large, it will exceed the battery cell 101, affecting the assembly of the battery cell 101 with the casing. Therefore, C is set to a value within the above range, so that the heating heat from the heating plate 4 can cover all the battery cells 101, ensuring that each battery cell 101 can be heated simultaneously in a low-temperature environment.

[0089] Furthermore, preferably, the heating plate 4 is centered relative to the side of the battery cell assembly 1. That is, the installation position of the heating plate 4 is centered vertically and horizontally relative to the corresponding side of the battery cell assembly 1, which not only meets the heating requirements but also makes the arrangement more coordinated and neat. Of course, this is not the only option.

[0090] In this embodiment, preferably, as follows: Figure 2 As shown, the battery pack also includes a bottom foam 19, which is attached to the bottom of the cell assembly 1 along the height direction of the cell 101.

[0091] As can be seen from the structure described above, the bottom foam 19 is bonded to the bottom of the battery cell assembly 1 to protect the battery cell 101.

[0092] In this embodiment, preferably, the battery pack further includes a housing (not shown in the figure), and the cell assembly 1, two end plates 2, two clamping plates 3 and heating plate 4 are all disposed inside the housing, and the interior of the housing is filled with thermally conductive adhesive 20.

[0093] As described above, by injecting adhesive into the casing, the adhesive flows between the bottom of the cell assembly 1 and the bottom of the casing, between the side of the cell assembly 1 and the side of the casing, and between two adjacent cells 101. This allows the heat from the heating plate 4 to be conducted to the top, bottom, and four sides of the cell assembly 1, and also to the interior of the cell assembly 1. This enables the heat to be distributed more quickly and evenly to all cells 101, thus providing all-around heating for the cells 101. This results in a small temperature difference between the cells 101 and high temperature uniformity, greatly improving the low-temperature performance of the battery pack and increasing its lifespan.

[0094] In addition, the circuit board and the top of the battery cell 101 and the outer casing can be bonded together with adhesive, thereby fixing the circuit board without the need for other additional fixing operations. This is simple, convenient, saves process steps, and reduces labor costs.

[0095] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A battery pack, characterized in that, include: The battery cell assembly comprises two end plates, two clamping plates, and a heating plate; wherein the battery cell assembly includes a plurality of battery cells stacked sequentially along a first preset direction, and the two end plates are respectively disposed at both ends of the battery cell assembly along the first preset direction. Along the second preset direction, the two clamping plates are respectively disposed on opposite sides of the battery cell assembly, and each clamping plate is connected to the two end plates respectively; at least one clamping plate is provided with a heating plate between it and the battery cell assembly.

2. The battery pack according to claim 1, characterized in that, The battery pack also includes a heat insulation layer, which is disposed between the heating plate and the clamping plate.

3. The battery pack according to claim 1, characterized in that, The heating plate is connected to the side of the battery cell assembly via thermally conductive adhesive.

4. The battery pack according to claim 1, characterized in that, The battery pack also includes a sampling circuit board and a conductive component; wherein, along the height direction of the battery cell, the sampling circuit board is disposed on the top of the battery cell assembly, and the conductive component is disposed on the side of the sampling circuit board opposite to the battery cell assembly and connected to the circuit board; The sampling circuit board has multiple through holes, and the positive and negative tabs of any two adjacent cells pass through the corresponding through holes, bend, and overlap. The positive tab, the negative tab, and the conductive component are welded together.

5. The battery pack according to claim 4, characterized in that, The battery pack further includes a main positive lead and a main negative lead disposed on the circuit board. Along the first preset direction, the positive tab of one of the first and last cells passes through the corresponding through hole and bends on the main positive lead, and is connected to the main positive lead by welding. The negative tab of the other cell passes through the corresponding through hole and bends on the main negative lead, and is connected to the main negative lead by welding.

6. The battery pack according to claim 5, characterized in that, The battery pack also includes a battery management module, which is disposed on the side of one of the end plates opposite to the cell assembly; the total negative lead is electrically connected to the battery management module; The battery pack also includes a total positive electrode and a total negative electrode. The total positive electrode is electrically connected to the total positive lead-out; the total negative electrode is electrically connected to the battery management module; and the heating plate is electrically connected to the battery management module.

7. The battery pack according to claim 6, characterized in that, The battery pack also includes a connector disposed on the circuit board, and the connector is disposed close to the battery management module along the first preset direction; the connector is electrically connected to the battery management module.

8. The battery pack according to claim 5, characterized in that, The battery pack also includes an insulating sheet disposed on the side of the circuit board opposite to the cell assembly, and the insulating sheet covers the outside of the positive electrode tab and the negative electrode tab; The battery pack also includes tab foam, which covers the outside of the insulating sheet.

9. The battery pack according to claim 1, characterized in that, The end plate includes a flat plate portion and a U-shaped reinforcing plate portion; wherein, there are multiple flat plate portions and U-shaped reinforcing plate portions, which are alternately arranged and connected along the height direction of the battery cell, and the flat plate portions are located at the top and bottom positions; the opening of the U-shaped reinforcing plate portion is arranged facing the battery cell assembly side.

10. The battery pack according to claim 9, characterized in that, The clamping plate includes a main body and an L-shaped bend connected to each other; wherein, along the first preset direction, the L-shaped bend is disposed at one end of the main body, and the L-shaped bend cooperates with the U-shaped reinforcing plate and is detachably connected by a fastening member.

11. The battery pack according to any one of claims 1 to 10, characterized in that, A buffer layer is provided between any two adjacent battery cells; and / or A buffer layer is provided between the battery cell assembly and the end plate; and / or The battery pack also includes multiple heat insulation layers, and the multiple heat insulation layers are sequentially inserted inside the cell assembly; and / or Along the second preset direction, the projection of the heating plate falls within the projection of the battery cell assembly, and a gap C exists between the edges of their projections, where 0.2t ≤ C ≤ 0.6t, and t is the thickness of the battery cell along the first preset direction; and / or The heating plate is centered relative to the side of the battery cell assembly; and / or The battery pack further includes a housing, and the cell assembly, the two end plates, the two clamping plates, and the heating plate are all disposed within the housing, and the interior of the housing is filled with thermally conductive adhesive; and / or The battery pack also includes bottom foam, which is adhered to the bottom of the cell assembly along the height direction of the cell.

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