Liquid-cooled battery pack

Abstract

The utility model provides a liquid-cooled battery pack, and belongs to the field of secondary batteries. The liquid-cooled battery pack comprises a shell, a single-group unit and at least one double-group unit, the single-group unit and the at least one double-group unit are arranged in the shell along a first direction, a first liquid-cooled plate is arranged between two battery cell groups in the double-group unit, and a second liquid-cooled plate is arranged between at least one side of the single-group unit and the battery cell group adjacent to the single-group unit; the side, close to the single-group unit, of the second liquid cooling plate is in heat conduction connection with the single-group unit, and the other side of the second liquid cooling plate is provided with a heat insulation structure used for heat insulation between the second liquid cooling plate and the corresponding adjacent double-group unit. According to the utility model, the second liquid cooling plate is arranged between the battery cell group of the single group unit and the adjacent battery cell group, and the thermal insulation layer is arranged on one side, far away from the single group unit, of the second liquid cooling plate, so that the temperature of each battery cell is uniform, and the second liquid cooling plate is ensured not to be degummed after the battery cells are expanded.

Description

Technical Field

[0001] The utility model belongs to the field of secondary batteries, and in particular relates to a liquid-cooled battery pack. Background Art

[0002] Batteries in new energy vehicles have strict operating temperature requirements. Operating temperatures that are too low or too high can affect the battery's lifespan. To improve battery temperature control, new energy vehicles are gradually adopting liquid-cooled battery packs. The bottom of a liquid-cooled battery pack is equipped with a liquid cooling baseplate that contacts the battery cells to quickly dissipate heat when the cells generate excessive heat.

[0003] However, dissipating heat only from the bottom of the cell is inefficient and affects the cell's lifespan. To address this issue, a liquid cooling plate can be added to one side of the cell to improve the cell's heat dissipation capacity. However, when adding a liquid cooling plate, the temperature uniformity of each cell must be considered. That is, the heat dissipation capacity of each cell must be equal to prevent inconsistent cell lifespans.

[0004] The battery cells are generally arranged in a row along the second direction (perpendicular to the first direction) to form a battery cell module (i.e., a battery cell group) with a single row of battery cells. The battery cell modules are arranged along the first direction in the battery pack. Currently, the liquid cooling plate is usually set on one side of the battery cell module by bonding. When there are multiple battery cell modules, a liquid cooling plate is affixed to each battery cell module, and adjacent battery cell modules are spaced apart. For example, when there are three battery cell modules, the liquid cooling plates of the battery cell modules on both sides are affixed to the outside of the corresponding battery cell modules, and the liquid cooling plate of the battery cell module in the middle can be affixed to any side of the first direction. The battery cell module in the middle is spaced apart from the battery cell modules on both sides to prevent the liquid cooling plate in the middle from affecting the temperature of the battery cell modules on both sides. However, in this solution, only one side of each liquid cooling plate can bear force. After the battery cell expands after long-term use, the side wall of the battery cell will bulge. The side wall of the battery cell will no longer be a flat structure, causing the liquid cooling plate and the battery cell to debond. The liquid cooling plate and the battery cell cannot effectively contact each other, resulting in poor heat dissipation effect.

[0005] The existing Chinese invention patent application with application publication number CN115692932A and application publication date of February 3, 2023 discloses a heavy-duty truck power battery pack, comprising a base and a plurality of dual-group units (i.e., battery modules) arranged along a first direction on the base. Each dual-group unit has two battery cell groups arranged along the first direction, and each battery cell group includes a plurality of battery cells arranged along a second direction. Each dual-group unit is equipped with a liquid cooling plate, which is sandwiched between the two battery cell groups within the same dual-group unit. In this technical solution, the liquid cooling plate sandwiched between the two battery cell groups can dissipate heat from the sides of the battery cells, improving the heat dissipation efficiency of the battery cells. In addition, each battery cell has a side heat dissipation system, and the heat dissipation efficiency and effect of each battery cell are the same, ensuring uniform temperature of each battery cell.

[0006] In the case of limited installation space, the number of cell groups in a battery pack may be an odd number greater than three. When the cell groups are paired to form a double-group unit, one cell group remains and forms a single-group unit. This cell group requires a separate liquid cooling plate. If the liquid cooling plate is sandwiched between the single-group unit and the adjacent cell group, it will also cool the adjacent cell group, thereby enhancing the heat dissipation capacity of the adjacent cell group, causing its temperature to be inconsistent with that of the remaining cell groups, affecting the overall life of the battery pack. If the liquid cooling plate is glued to the outside of the single-group unit, it will easily become debonded after the cell expands, resulting in poor heat dissipation for that part of the cell, and ultimately causing the temperature of the single-group unit to be inconsistent with that of the other cell groups, affecting the overall life of the battery pack. Utility Model Content

[0007] The purpose of the present utility model is to provide a liquid-cooled battery pack to solve the technical problem in the prior art that when there is a single group of units, no matter whether the liquid cooling plate is set between the single group of units and the adjacent battery cell group or set outside the single group of units, it will cause inconsistent battery cell group temperature and affect the overall life of the battery pack.

[0008] To achieve the above objectives, the technical solution of the liquid-cooled battery pack provided by the present invention is:

[0009] A liquid-cooled battery pack includes a shell and a single-group unit and at least one double-group unit arranged along a first direction within the shell, the double-group unit including two battery cell groups arranged along the first direction, the single-group unit including one battery cell group including multiple battery cells arranged along a second direction perpendicular to the first direction, a first liquid-cooling plate is provided between the two battery cell groups in the double-group unit, a second liquid-cooling plate is provided between at least one side of the single-group unit and an adjacent battery cell group, the second liquid-cooling plate is thermally connected to the single-group unit on one side close to the single-group unit, and an insulation structure is provided on the other side of the second liquid-cooling plate for insulating between the second liquid-cooling plate and the corresponding adjacent double-group unit.

[0010] As a further improvement, a thermally conductive structural adhesive is provided between the second liquid cooling plate and the single group of units. The second liquid cooling plate and the single group of units are thermally connected through the thermally conductive structural adhesive. The thermally conductive structural adhesive is preset on the second liquid cooling plate or filled between the second liquid cooling plate and the single group of units.

[0011] As a further improvement, the thermal insulation structure is an insulation layer; or the thermal insulation structure includes an insulation space and a thermal insulation support structure provided in the insulation space for providing pressure support between the second liquid cooling plate and the corresponding adjacent dual group units.

[0012] As a further improvement, the thermal insulation structure is a thermal insulation layer, which is pasted or sprayed on the second liquid cooling plate, or filled and arranged between the second liquid cooling plate and the corresponding dual-group unit.

[0013] As a further improvement, the heat dissipation power of the first liquid cooling plate is equivalent to the heat generation power of the double-group unit, and the sum of the heat dissipation power of each second liquid cooling plate corresponding to the single-group unit is equivalent to the heat generation power of the single-group unit.

[0014] As a further improvement, the heat insulating layer is arranged in close contact with the side walls of the adjacent double-group units.

[0015] As a further improvement, the single-group unit is located outside all the double-group units, and the second liquid cooling plate is only provided inside the single-group unit.

[0016] As a further improvement, there are at least two double-group units, and the single-group unit is located between two adjacent double-group units. The second liquid cooling plate is only provided on one side of the single-group unit or on both sides of the single-group unit.

[0017] As a further improvement, the compression rate of the heat insulation layer is 20%-50%.

[0018] As a further improvement, the heat insulation layer is a silicone foam layer.

[0019] The beneficial effect is that the liquid-cooled battery pack provided by the present invention belongs to an invention of the element-changing type. There is a single-group unit in the liquid-cooled battery pack, and the single-group unit is independently equipped with a second liquid-cooling plate. The second liquid-cooling plate is arranged in the single-group unit and between the adjacent battery cell groups. A heat-conducting structure is provided on one side of the second liquid-cooling plate close to the single-group unit, and a heat-insulating structure is provided on the other side. Thus, the second liquid-cooling plate can be used to cool the single-group unit while preventing the heat of the battery cell group in the adjacent double-group unit from being transferred to the second liquid-cooling plate, which causes uneven temperature of the battery cell group. After long-term use and normal expansion of the battery cell, the single-group unit and the adjacent double-group unit squeeze the second liquid-cooling plate at the same time. Not only will the second liquid-cooling plate and the battery cell group in the single-group unit not debond, but they can also fit more tightly to the single-group unit under squeezing, maintain good heat conduction, and prevent the heat dissipation of the battery cell in the single-group unit from deteriorating and affecting the overall life of the battery pack. In addition, after the battery cells expand, the side of the single unit where the second liquid cooling plate is provided can be squeezed, so that the single unit is constrained, which is also beneficial to extending the service life of the battery cells in the single unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is an exploded view of an embodiment of a liquid-cooled battery pack of the present invention;

[0021] Figure 2This is a schematic diagram of the arrangement structure of each battery cell group in an embodiment of the liquid-cooled battery pack of the present invention;

[0022] Figure 3 This is a schematic structural diagram of the first liquid cooling plate and the second liquid cooling plate in one embodiment of the liquid-cooled battery pack of the present invention;

[0023] Figure 4 This is a schematic structural diagram of the second liquid cooling plate in one embodiment of the liquid-cooled battery pack of the present invention.

[0024] Description of reference numerals:

[0025] 1. Upper shell; 2. Lower shell; 3. End plate; 4. Liquid-cooled base plate; 5. First battery cell group; 6. Second battery cell group; 7. Third battery cell group; 8. First liquid-cooled plate; 9. Second liquid-cooled plate; 10. Cold plate body; 11. First cold plate current collector; 12. Second cold plate current collector; 13. Groove; 14. Liquid inlet interface; 15. Wiring side; 16. Drainage tube; 17. Thermal insulation layer. DETAILED DESCRIPTION

[0026] The present invention is further described in detail below with reference to the embodiments.

[0027] In order to solve the problems in the prior art, the main idea of ​​the present invention is to set a second liquid cooling plate between the battery cell group of a single unit and the adjacent battery cell group, and set an insulation layer on the side of the second liquid cooling plate away from the single unit, so as to ensure that the temperature of each battery cell is uniform and the second liquid cooling plate will not debond after the battery cell expands.

[0028] Specific embodiment 1 of the liquid-cooled battery pack provided by the present utility model:

[0029] A liquid-cooled battery pack, see attached Figure 1 , comprising a shell, the shell comprising a lower shell 2 and an upper shell 1 that can be buckled together. The width direction and the length direction of the shell are respectively a first direction and a second direction.

[0030] See attached Figure 1 and attached Figure 2 The housing contains three battery modules equidistantly arranged along the first direction. In this embodiment, the battery modules are all single-row modules, meaning each module includes multiple cells arranged in a row along the second direction. Therefore, in this embodiment, one battery module constitutes a battery group. End plates 3 are provided in the middle and at both ends of the battery module. Structural adhesive is applied between adjacent cells in the same module and between the end plates 3 and the cells, forming the entire module into a single unit. Cable ties are also provided outside the module to secure the end plates 3 and the cells.

[0031] A liquid-cooling baseplate 4 is fixed to the bottom of the lower housing 2. The bottom of each cell module is bonded to the liquid-cooling baseplate 4 with thermally conductive structural adhesive, securing the position of each cell module. Furthermore, the end plate 3 is provided with through-holes for bolts to pass through along the height direction. Bolts are inserted into the end plate 3 and then connected to the bottom wall of the lower housing 2, thereby securing the end plate 3 to the lower housing 2 and further ensuring the stability of each cell module.

[0032] The three battery cell modules are arranged in the order of a first battery cell module 5 , a second battery cell module 6 , and a third battery cell module 7 . The first battery cell module 5 and the second battery cell module 6 form a double unit, and the third battery cell module 7 forms a single unit.

[0033] See attached Figure 1 and attached Figure 3 A first liquid cooling plate 8 is provided between the first battery cell module 5 and the second battery cell module 6. Thermal conductive structural adhesive is provided on both sides of the first liquid cooling plate 8 so as to bond the first battery cell module 5 and the second battery cell module 6 together. Each battery cell in the first battery cell module 5 and the second battery cell module 6 is also bonded to the first liquid cooling plate 8.

[0034] A second liquid cooling plate 9 is provided between the second cell module 6 and the third cell module 7. The side of the second liquid cooling plate 9 closest to the third cell module 7 is thermally connected to the third cell module 7 to transfer heat from the third cell module 7 to the second liquid cooling plate 9. A heat-insulating structure is provided on the side of the second liquid cooling plate 9 away from the third cell module 7 to insulate between the second cell module 6 and the second liquid cooling plate 9, preventing heat from the second cell module 6 from being transferred to the second liquid cooling plate 9.

[0035] In this embodiment, a thermally conductive structural adhesive is provided between the second liquid cooling plate 9 and the third battery cell module 7. The thermally conductive structural adhesive can be pre-set on the second liquid cooling plate 9 by coating, and then the second liquid cooling plate 9 is adhered to the third battery cell module 7. Alternatively, the second liquid cooling plate 9 can be installed in the lower housing 2, and then the third battery cell module 7 is installed, and finally the thermally conductive structural adhesive is filled between the third battery cell module 7 and the second liquid cooling plate 9. In other embodiments, the second liquid cooling plate 9 can be directly in close contact with the third battery cell module 7, and the second liquid cooling plate 9 and the third battery cell module 7 are thermally connected by close contact, so that heat is directly transferred from the third battery cell module 7 to the second liquid cooling plate 9 without passing through a medium.

[0036] In this embodiment, see the attached Figure 4 The thermal insulation structure is an insulation layer 17, which can be pre-set on the second liquid cooling plate 9 by pasting or spraying; the second liquid cooling plate 9 can also be installed in the lower shell 2, and then the third battery module 7 is installed, and finally the insulation material is filled between the third battery module 7 and the second liquid cooling plate 9 to form the insulation layer 17.

[0037] The heat dissipation power of the first liquid cooling plate 8 is equivalent to the heat generation power of the double-group unit, and the heat dissipation power of the second liquid cooling plate 9 is equivalent to the heat generation power of the single-group unit. Since the first liquid cooling plate 8 needs to cool two battery modules, it needs to have a stronger cooling capacity than the first liquid cooling plate 8 to ensure that the temperature of each battery module is uniform. Specifically, when the flow channel arrangement and flow channel wall thickness of the second liquid cooling plate 9 are the same as those of the first liquid cooling plate 8, the flow channel width of the second liquid cooling plate 9 is made smaller than the flow channel width of the first liquid cooling plate 8, so that the flow rate of the coolant in the second liquid cooling plate 9 matches the heat dissipation power required by it, and the flow rate of the coolant in the first liquid cooling plate 8 matches the heat dissipation power required by it.

[0038] From the appearance, the thickness of the second liquid cooling plate 9 is less than that of the first liquid cooling plate 8. In order to facilitate the equal spacing of the battery modules, in this embodiment, the overall thickness of the second liquid cooling plate 9 plus the insulation layer 17 is equal to the thickness of the first liquid cooling plate 8, and the second battery module 6 is just in contact with the insulation layer 17.

[0039] During use, coolant is passed into the liquid-cooled base plate 4, the first liquid-cooled plate 8, and the second liquid-cooled plate 9. The liquid-cooled base plate 4 can cool the bottom of the battery cell, the first liquid-cooled plate 8 can cool one side of the battery cells in the first battery cell module 5 and the second battery cell module 6, and the second liquid-cooled plate 9 can cool one side of the battery cells in the third battery cell module 7. Each battery cell is cooled at the bottom and one side, so the heat dissipation capacity of each battery cell is the same, ensuring that the temperature of each battery cell is uniform during use, preventing the temperature of some battery cells from being too high or too low, affecting their service life, and thereby reducing the overall service life of the battery pack.

[0040] After extended use, the battery cells undergo normal expansion, and the first and second battery modules 5 and 6 simultaneously apply pressure in opposite directions to both sides of the first liquid cooling plate 8. Due to compression, the corresponding side walls where the battery cells connect to the first liquid cooling plate 8 will not bulge, or the bulging will be minimal. This ensures the effective contact area between the first and second battery modules 5 and 6 and the first liquid cooling plate 8, maintaining a good cooling effect. The second and third battery modules 6 and 7 simultaneously apply pressure in opposite directions to both sides of the second liquid cooling plate 9. Due to compression, the corresponding side walls where the battery cells in the third battery module 7 connect to the second liquid cooling plate 9 will not bulge, or the bulging will be minimal. This ensures the effective contact area between the third battery module 7 and the second liquid cooling plate 9, maintaining a good cooling effect for the third battery module 7.

[0041] Furthermore, since both sides of the thickness direction of the first and second liquid cooling plates 8 and 9 are shielded, condensation can be effectively reduced. To further reduce condensation, foam pads can be attached to both sides of the first and second liquid cooling plates 8 and 9 in the vertical direction and in the second direction to prevent direct contact between the first and second liquid cooling plates 8 and 9 and the air.

[0042] The cells in the second and third cell modules 6 and 7 expand and squeeze the insulation layer 17, which can easily deform. If the insulation layer 17 is compressed significantly, its insulation performance deteriorates, and heat from the second cell module 6 is more easily transferred to the second liquid cooling plate 9. This can cause the temperature of the second cell module 6 to differ from that of the other cell modules after prolonged use. Furthermore, if the insulation layer 17 is compressed significantly, this also indicates significant cell expansion, which can reduce the contact area between the second liquid cooling plate 9 and the third cell module 7. To ensure the thermal insulation effect of the thermal insulation layer 17 after being compressed and to ensure that the second liquid cooling plate 9 and the third battery module 7 maintain good contact, the compression rate of the thermal insulation layer 17 needs to be 20%-50%. In this embodiment, the thermal insulation layer 17 is a silicone foam with a compression rate within the above range. Silicone foam has a low compression rate and good resilience after long-term compression, which can effectively ensure that it can maintain good thermal insulation performance after long-term use. In other embodiments, other materials with a compression rate that meets the requirements can also be used as the thermal insulation layer 17, such as an insulating quartz sheet.

[0043] In other embodiments, the thermal insulation layer 17 may initially only contact the second battery cell module without being pressed against it. As the battery cell expands, the thermal insulation layer 17 and the second battery cell module may be pressed against each other more and more.

[0044] In other embodiments, the number of double-group units can also be two or three, and the single-group unit is arranged on the outside of all double-group units, that is, the single-group unit is located at the edge. At this time, the setting method of the second liquid cooling plate is the same as in the above embodiment and will not be repeated here.

[0045] Specific embodiment 2 of the liquid-cooled battery pack provided by the present utility model:

[0046] This embodiment is based on Example 1, and differs from Example 1 in that, in this embodiment, there are two double-group units, a single-group unit is arranged between the two double-group units, and one second liquid cooling plate is arranged between the single-group unit and one of the double-group units.

[0047] The second liquid cooling plate is thermally connected to the single-group unit on one side, and a thermal insulation structure is provided between the other side of the second liquid cooling plate and the corresponding double-group unit. The specific form of the thermal connection and thermal insulation structure is the same as in Example 1 and will not be repeated here.

[0048] A gap is left between the single-group unit and another double-group unit. In other embodiments, the gap may also be filled with heat-insulating material to reduce the impact of the temperature between the battery cell groups.

[0049] In other embodiments, the number of double-group units can also be three. In this embodiment, the single-group unit is arranged between any two adjacent double-group units. The arrangement of the second liquid cooling plate is the same as that in the above-mentioned embodiment of this embodiment, and will not be repeated here.

[0050] In this embodiment, the heat dissipation power of the first liquid cooling plate is equivalent to the heat generation power of the double-group unit through the design of the flow channel and size, and the heat dissipation power of the second liquid cooling plate is equivalent to the heat generation power of the single-group unit, which will not be elaborated here.

[0051] Specific embodiment 3 of the liquid-cooled battery pack provided by the present utility model:

[0052] This embodiment is based on Example 2, and differs from Example 2 in that two second liquid cooling plates are provided in this embodiment, and the two second liquid cooling plates are respectively provided on both sides of the single-group unit, that is, a second liquid cooling plate is provided between the single-group unit and the two adjacent double-group units.

[0053] The second liquid cooling plate is thermally connected to the single-group unit on one side, and a thermal insulation structure is provided between the other side of the second liquid cooling plate and the corresponding double-group unit. The specific form of the thermal connection and thermal insulation structure is the same as in Example 1 and will not be repeated here.

[0054] In other embodiments, the number of double-group units can also be three. In this embodiment, the single-group unit is arranged between any two adjacent double-group units. The arrangement of the second liquid cooling plate is the same as that in the above-mentioned embodiment of this embodiment, and will not be repeated here.

[0055] In this embodiment, the heat dissipation power of the first liquid cooling plate is equivalent to the heat generation power of the double-group unit through the design of the flow channel and size, and the sum of the heat dissipation power of the two second liquid cooling plates is equivalent to the heat generation power of the single-group unit. Details will not be given here.

[0056] Specific embodiment 4 of the liquid-cooled battery pack provided by the present utility model:

[0057] This embodiment is based on Example 1, and differs from Example 1 in that the thermal insulation structure in this embodiment includes a thermal insulation space, and a thermal insulation support structure for top pressure support between the second liquid cooling plate and the second battery cell module is provided in the thermal insulation space.

[0058] Specifically, the thermal insulation support structure can be a plurality of thermal insulation support pads adhered to the second liquid cooling plate. After the second liquid cooling plate is adhered to the side of the third battery cell module by gluing, the second liquid cooling plate is installed together with the third battery cell module. At this time, a thermal insulation space is reserved between the second liquid cooling plate and the second battery cell module to prevent heat from the second battery cell module from being transferred to the second liquid cooling plate. The thermal insulation support pads can transfer the top pressure of the second battery cell module to the second liquid cooling plate, thereby preventing the second liquid cooling plate and the third battery cell module from becoming debonded after the battery cell expands.

[0059] In other embodiments, the thermal insulation support structure may also be a multi-insulation support frame, which is a frame structure made of insulation material and is used to transmit force between the second battery cell module and the second liquid cooling plate, which will not be elaborated here.

[0060] Specific embodiment 5 of the liquid-cooled battery pack provided by the present utility model:

[0061] This embodiment is based on Example 1 and differs from Example 1 in that a cell module is disposed within the housing in this embodiment. The cell module in this embodiment comprises three columns of cells, each column comprising multiple cells arranged along the second direction. Each column of cells is arranged along the first direction, and in this embodiment, a column of cells constitutes a cell group. This embodiment also includes end plates disposed in the middle and at both ends of the cell module. The width of the end plates in the first direction is equal to the sum of the dimensions of the three columns of cells in the first direction. Ties are disposed on the outside of the cell module for bundling the end plates and the columns of cells.

[0062] In this embodiment, the three columns of battery cells are, in order, the first column of battery cells, the second column of battery cells, and the third column of battery cells, wherein the first column of battery cells and the second column of battery cells constitute a double-group unit, and the third column of battery cells constitutes a single-group unit. A first liquid cooling plate is provided between the first column of battery cells and the second column of battery cells, and a second liquid cooling plate is provided between the second column of battery cells and the third column of battery cells. The first liquid cooling plate is thermally connected to both the first column of battery cells and the second column of battery cells, while the second liquid cooling plate is thermally connected only to the third column of battery cells, but a thermal insulation structure is provided between the second liquid cooling plate and the second column of battery cells. The specific configuration of the thermal connection and the thermal insulation structure is similar to that in Example 1 and will not be described in detail here.

[0063] Specific embodiment 6 of the liquid-cooled battery pack provided by the present utility model:

[0064] This embodiment is based on Example 5, and differs from Example 5 in that two battery cell modules are disposed within the housing in this embodiment. One of the battery cell modules in this embodiment has two columns of battery cells, and the other has a single column of battery cells. Each column of battery cells in the two battery cell modules includes a plurality of battery cells arranged along the second direction, and each column of battery cells is arranged along the first direction. In this embodiment, one column of battery cells constitutes a battery cell group. End plates are also disposed in the middle and at both ends of the battery cell module in this embodiment, which will not be described in detail here.

[0065] In a battery module with two rows of cells, the cells farthest from the other module are the first row, the cells adjacent to the other module are the second row, and the cells in a battery module with a single row of cells are the third row. A battery module with two rows of cells forms a double unit, while a battery module with a single row of cells forms a single unit.

[0066] In this embodiment, a first liquid cooling plate is provided between the first and second rows of cells, and a second liquid cooling plate is provided between the cell module with a single row of cells and the cell module with two rows of cells. The first liquid cooling plate is thermally connected to both the first and second rows of cells, while the second liquid cooling plate is thermally connected only to the third row of cells. However, a thermal insulation structure is provided between the second liquid cooling plate and the second row of cells. The specific configuration of the thermal connection and the thermal insulation structure is not detailed here.

[0067] Finally, it should be noted that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments without inventive effort, or replace some of the technical features therein with equivalents. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A liquid-cooled battery pack, characterized in that: The invention comprises a shell and a single-group unit and at least one double-group unit arranged along a first direction in the shell, the double-group unit comprising two battery cell groups arranged along the first direction, the single-group unit comprising a battery cell group comprising a plurality of battery cells arranged along a second direction perpendicular to the first direction, a first liquid cooling plate being arranged between the two battery cell groups in the double-group unit, a second liquid cooling plate being arranged between at least one side of the single-group unit and the battery cell group adjacent thereto, a side of the second liquid cooling plate close to the single-group unit being thermally connected to the single-group unit, and a heat insulating structure for heat insulating between the second liquid cooling plate and the corresponding adjacent double-group unit being provided on the other side of the second liquid cooling plate.

2. The liquid-cooled battery pack according to claim 1, wherein: A thermally conductive structural adhesive is provided between the second liquid cooling plate and the single group of units. The second liquid cooling plate and the single group of units are thermally connected through the thermally conductive structural adhesive. The thermally conductive structural adhesive is preset on the second liquid cooling plate or filled between the second liquid cooling plate and the single group of units.

3. The liquid-cooled battery pack according to claim 1 or 2, characterized in that the thermal insulation The structure is an insulation layer; or the insulation structure includes an insulation space and an insulation support structure provided in the insulation space for supporting the second liquid cooling plate and the corresponding adjacent double group units with top pressure.

4. The liquid-cooled battery pack according to claim 3, characterized in that the thermal insulation The structure is a heat insulation layer, which is pasted or sprayed on the second liquid cooling plate, or filled and arranged between the second liquid cooling plate and the corresponding dual group unit.

5. The liquid-cooled battery pack according to claim 1 or 2, characterized in that: The heat dissipation power of the first liquid cooling plate is equivalent to the heat generation power of the double-group unit, and the sum of the heat dissipation power of each second liquid cooling plate corresponding to the single-group unit is equivalent to the heat generation power of the single-group unit.

6. The liquid-cooled battery pack according to claim 3, wherein: The heat insulation layer is tightly arranged against the side walls of the adjacent double-group units.

7. The liquid-cooled battery pack according to claim 1 or 2, characterized in that: The single-group unit is located outside all the double-group units, and the second liquid cooling plate is only provided on the inner side of the single-group unit.

8. The liquid-cooled battery pack according to claim 1 or 2, characterized in that: There are at least two double-group units, and the single-group unit is located between two adjacent double-group units. The second liquid cooling plate is only provided on one side of the single-group unit or on both sides of the single-group unit.

9. The liquid-cooled battery pack according to claim 3, wherein: The compression rate of the thermal insulation layer is 20%-50%.

10. The liquid-cooled battery pack according to claim 9, wherein: The thermal insulation layer is a silicone foam layer.

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