Liquid-cooled battery pack

Abstract

The utility model discloses a liquid cooling type battery pack which comprises a middle liquid cooling plate arranged in a box body frame, the upper surface and the lower surface of the middle liquid cooling plate are respectively provided with a layer of battery cell module, each layer of battery cell module comprises a plurality of columns of battery cells, and a large surface of each battery cell is opposite to the upper surface / the lower surface of the middle liquid cooling plate; a battery cell heat-conducting bottom plate is arranged on the bottom surface, far away from the battery cell pole columns, of each column of battery cells; and each layer of battery cell module is connected with the middle liquid cooling plate, the upper cover cooling plate or the bottom cooling plate through a heat conduction layer structure formed by the battery cell heat conduction bottom plate and the heat conduction pad. According to the utility model, the multi-surface cooling of the battery module is realized, the two large surfaces of the battery can be cooled, and the battery cell heat conduction bottom plate and the heat conduction pad form a heat conduction layer to be in contact with the upper cover cold plate, the bottom cold plate and the middle liquid cooling plate, so that the bottom surface of the battery cell can be cooled, and a better cooling effect can be achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of battery packs, in particular to a liquid-cooled battery pack. Background Art

[0002] With the rapid development of the electric vehicle market, the performance and safety of battery systems have received more and more attention. Among them, the battery cooling system is an important part of the battery system, which directly affects the performance and life of the battery. Liquid cooling system is widely used in battery systems due to its advantages such as good cooling effect and uniform cooling.

[0003] In existing liquid-cooled battery packs, the internal cells are mostly placed upright, with a liquid cooling plate placed at the bottom of the cell to cool the bottom of the cell; another cooling method is to place a liquid cooling plate on the side of the cell for large-surface cooling. This liquid cooling system usually requires a large number of liquid cooling pipes, which not only increases the complexity and cost of the system, but also reduces the grouping rate of the battery system. In addition, existing liquid-cooled battery packs only focus on cooling the cell body, and pay little attention to cooling the busbar of the module. Utility Model Content

[0004] The purpose of the utility model is to provide a liquid-cooled battery pack in order to overcome the deficiencies and defects of the prior art.

[0005] A liquid-cooled battery pack comprises a central liquid cooling plate arranged in a box frame, wherein a layer of battery cell modules are arranged on the upper surface and the lower surface of the central liquid cooling plate respectively, and each layer of battery cell modules comprises a plurality of columns of battery cells, and a large surface of each of the battery cells is opposite to the upper surface / lower surface of the central liquid cooling plate; a battery cell heat-conducting bottom plate is arranged on the bottom surface of each column of battery cells away from the battery cell poles; and each layer of the battery cell modules is connected to the central liquid cooling plate, the upper cover cold plate or the bottom cold plate via the battery cell heat-conducting bottom plate.

[0006] The heat-conducting bottom plate of the battery cell is an I-shaped structure, and the length of the heat-conducting bottom plate of the battery cell is adapted to the length of the battery cell in the row.

[0007] Among them, thermal pads are arranged between the battery cell and the middle liquid cooling plate, the cover plate and the bottom plate, and the battery cell thermal bottom plate is connected to the middle liquid cooling plate, the upper cover cold plate or the bottom cold plate through the thermal pads.

[0008] Among them, in two adjacent columns of battery cells, the pole side of one column of battery cells is separated from the bottom surface of the other column of battery cells by the battery cell heat conductive bottom plate.

[0009] Wherein, an insulating heat-resistant sheet is arranged between the battery core heat-conducting bottom plate and the bottom surface of the battery core.

[0010] Wherein, the length of the insulating heat-resistant sheet is adapted to the length of the battery cells in the row.

[0011] Wherein, each column of the battery cells is bonded and fixed to the insulating heat-resistant sheet and the battery cell heat-conductive bottom plate respectively configured therein.

[0012] The pole of the battery cell is placed in a groove on one side of the I-shaped thermal conductive bottom plate of the battery cell, and a heat-insulating coating is arranged on the surface of the groove.

[0013] Among them, the flat surfaces at the upper and lower ends of the I-shaped thermal conductive bottom plate of the battery cell are respectively flush with the thermal conductive pads arranged on both sides of the battery cell module, and are respectively connected to the thermal conductive pads on both sides of the battery cell module to form a thermal conductive layer structure of the battery cell module.

[0014] Among them, one side of the busbar connected to the front end pole of the battery cell is connected to the busbar insulating thermal conductive part, and the busbar insulating thermal conductive part is in contact with the battery cell thermal conductive bottom plate surface for heat conduction to transfer the heat of the busbar to the middle liquid cooling plate.

[0015] Wherein, the middle liquid cooling plate is fixed to the inner wall of the box frame, and the upper cover cooling plate and the bottom cooling plate are fixedly connected to the lower end and the bottom end of the box frame.

[0016] The liquid-cooled battery pack of the utility model can realize multi-sided cooling of the battery module. In addition to cooling the two large surfaces of the battery, the bottom surface of the battery cell can be cooled by forming a heat-conducting layer through the heat-conducting bottom plate of the battery cell and the heat-conducting pad, which contacts the upper cover cold plate, the bottom cold plate and the middle liquid cooling plate, thereby achieving better cooling effect.

[0017] In addition, the liquid-cooled battery pack of the present invention is connected to a busbar insulating thermal conductive part through one side of the busbar connected to the front end pole of the battery cell. The busbar insulating thermal conductive part is contacted and connected with the battery cell thermal conductive bottom plate / the thermal conductive pad surface for heat conduction, which can further enhance the cooling effect of the battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is an exploded view of the liquid-cooled battery pack of the present invention.

[0019] Figure 2 The exploded view is of a row of cells of the connecting busbar insulating heat conductive member of the cell module of the utility model.

[0020] Figure 3 This is a schematic diagram of a layer of battery cell module assembly of the present invention located between the middle liquid cooling plate and the upper cover cooling plate.

[0021] Figure 4 It is a schematic diagram of the two-layer battery cell module of the present invention being located between a middle liquid cooling plate, an upper cover cooling plate and a bottom cooling plate.

[0022] Figure 5It is a schematic diagram of the connection of the liquid cooling pipeline of the battery pack of the present invention.

[0023] Description of reference numerals:

[0024] 10: top cover cold plate; 20, thermal pad; 30, battery cell; 40, middle liquid cold plate; 50, box frame; 60, bottom cold plate; 70, BDU (Battery Disconnect Unit) area;

[0025] 110. busbar; 111. busbar insulating heat-conducting member; 112. insulating heat-resistant sheet; 113. battery core heat-conducting bottom plate; 114. thermal insulation coating;

[0026] 12. Pipelines. DETAILED DESCRIPTION

[0027] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0028] like Figure 1 As shown, a liquid-cooled battery pack of an embodiment of the utility model includes a middle liquid cooling plate 40 arranged in a box frame 50, and a layer of battery cell modules are arranged on the upper surface and the lower surface of the middle liquid cooling plate respectively, and each layer of battery cell modules includes multiple columns of battery cells 30, and a large surface of each of the battery cells is opposite to the upper surface / lower surface of the middle liquid cooling plate; a battery cell thermal conductive bottom plate 113 is arranged on the bottom surface of each column of battery cells away from the battery cell poles; each layer of the battery cell modules is connected to the middle liquid cooling plate 40, the upper cover cold plate 10 or the bottom cold plate 60 through the thermal conductive layer structure formed by the battery cell thermal conductive bottom plate 113 and the thermal conductive pad 20.

[0029] In some embodiments, the battery cell thermally conductive base plate 113 is an I-shaped structure, and its upper plane and lower plane and the thermal conductive pad 20 are arranged between the battery cell and the upper cover cold plate and the bottom cold plate, separating the battery cell from the upper cover cold plate and the bottom cold plate, and its upper plane and lower plane are spliced ​​with the corresponding upper or lower conductive pad 20 to form a thermal conductive layer structure.

[0030] In some embodiments, the middle liquid cooling plate is fixed to the inner wall of the box frame, and the upper cover cold plate and the bottom cold plate are fixedly connected to the upper end and the bottom end of the box frame. The middle liquid cooling plate can be combined with the surrounding inner walls of the box during manufacturing, or can be manufactured separately and then connected and fixed together.

[0031] In the above technical solution, the upper cover cold plate is formed by integrating or combining the liquid cooling plate with the upper cover of the box body, and the bottom cold plate is formed by combining the liquid cooling plate with the bottom plate of the box body. It is a prior art structure and can be implemented by using an upper cover or bottom plate with an integrated liquid cooling plate or liquid cooling function in the prior art. The box body is a rectangular frame, which is fixed to the bottom cold plate and bolted to the upper cover cold plate. The material can be a profile. This is the conventional structure of the box body of the current battery pack.

[0032] In the present application, the thermal conductive bottom plate of the battery cell can be in contact with the liquid cooling plates on the upper and lower sides thereof, so as to achieve the effect of transferring the heat at the bottom of the battery cell to the liquid cooling plate, thereby realizing cooling of the bottom of the battery cell. The thermal conductive pad 20 can be a non-metallic elastic interlayer, and can be a modified polypropylene material MPP.

[0033] In the utility model, the large surfaces on the upper and lower sides of the battery cell are in contact with the middle liquid cooling plate, the upper cover cold plate and the bottom cold plate through the thermal conductive pad, so that the large surfaces on both sides of the battery cell can be cooled. Combined with the heat transfer of the thermal conductive bottom plate of the battery cell, three-side cooling of the large surfaces on both sides and the bottom of a single battery cell can be achieved.

[0034] In some embodiments, the battery cell modules are designed without modules and can be assembled by arranging and stacking them on the bottom cold plate and the middle liquid cold plate of the box. The water inlet and outlet of the middle liquid cold plate, the upper cold plate and the bottom cold plate are connected by pipes 12. The water inlet and outlet can be set on the outside of the upper cold plate, or the pipes can be built inside the box and extend the water inlet and outlet from the front side of the box. Figure 5 As shown, water inlet and outlet pipes are arranged on the outside of the upper cover cold plate. In this application, the pipeline layout is simple and only occupies a small amount of internal space. In practice, the pipeline needs to be designed according to the arrangement of parts inside the battery box.

[0035] Additionally, in some embodiments, inside the front side of the box frame is a BDU area 70 for assembling electrical components of the battery pack, such as electrical components for battery disconnection.

[0036] In the present application, one column of battery cells is provided with one thermally conductive bottom plate, so that in two adjacent columns of battery cells, the pole side of one column of battery cells is separated from the bottom surface of the other column of battery cells by the thermally conductive bottom plate, thereby preventing heat transfer between adjacent columns of battery cells.

[0037] In some embodiments, a thermal pad 20 is arranged between the battery cell and the middle liquid cold plate, the cover plate and the bottom plate. The thermal pad acts as a medium for heat transfer, ensuring the thermal conductivity of the large surface of the battery cell. In addition, the thermal pad itself can also absorb the expansion of the battery cell. In some embodiments, the thermal conductive bottom plate of the battery cell is an I-shaped structure, wherein the upper and lower flat surfaces of the thermal conductive bottom plate of the battery cell of the I-shaped structure are respectively flush with the thermal pads arranged on both sides of the battery cell module, and are respectively connected to the thermal pads on both sides of the battery cell module, and are spliced ​​to form a thermal conductive layer structure of the battery cell module. Through the cooperation of the I-shaped structure and the thermal conductive pad, a thermal conductive layer is formed between the battery cell and the cold plate, which can achieve better thermal conductivity of the large surface of the battery cell.

[0038] In the present application, the thermally conductive base plate of the battery cell is made of sheet metal or profile, and is bonded and fixed to the bottom of the battery cell. In some implementation schemes, an insulating heat-resistant sheet 112 is arranged between the thermally conductive base plate of the battery cell and the bottom surface of the battery cell, such as insulating mica, and is bonded and fixed to the bottom of the battery cell. The use of an insulating heat-resistant sheet can be used to protect the risk of thermal runaway of the battery cell, can effectively prevent the spread of thermal runaway of the battery cell, and improve the safety of the battery system.

[0039] In some embodiments, the length of the insulating heat-resistant sheet is adapted to the length of the battery cells in the column, and the length of the battery cell heat-conducting plate is adapted to the length of the battery cells in the column, and the insulating heat-resistant sheet is a whole or formed by splicing multiple pieces. In some embodiments, the battery cells in each column are bonded and fixed to the insulating heat-resistant sheet and the battery cell heat-conducting bottom plate respectively configured therein. After such pre-fixation, the battery pack is assembled to facilitate assembly.

[0040] The insulating heat-resistant sheet can isolate most of the heat of the battery cell and prevent the heat from being transferred to the battery cells in adjacent layers. The heat overflowing from the insulating heat-resistant sheet can be transferred to the liquid cooling plate through the battery cell thermal conductive bottom plate 113 to achieve cooling of the bottom of the battery cell.

[0041] In some embodiments, the pole of the battery cell is placed in a groove on one side of the I-shaped battery cell thermal conductive base plate, and a thermal insulation coating 114 is arranged on the surface of the groove, which can play a thermal insulation role and prevent the temperature of the bottom of the battery cell of an adjacent battery cell column from being transferred to the pole side of another adjacent battery cell column through the battery cell thermal conductive base plate.

[0042] In some embodiments, one side of the bus 110 connected to the front pole of the battery cell is connected to a bus insulating thermal conductive member 111, and the bus insulating thermal conductive member is in contact with the battery cell thermal conductive bottom plate surface for heat conduction, so as to transfer the heat of the bus to the middle liquid cooling plate, the upper cover cold plate 10 or the bottom cold plate 60. In this way, the heat of the bus can be transferred to the liquid cooling plate through the battery cell thermal conductive bottom plate, so as to achieve the effect of synchronously cooling the bus, so as to achieve the overcurrent requirements of the bus for high-rate charging. The bus insulating thermal conductive member 111 can be a block with a rectangular cross-section, which can be fixed to the bus by bonding or clamping with grooves on the surface, or it can be fixed by other structures, and each bus is connected to one of the bus insulating thermal conductive members 111.

[0043] In short, the liquid-cooled battery pack of the utility model can realize multi-sided cooling of the battery module. In addition to cooling the two large surfaces of the battery, it can also form a thermally conductive layer through the thermally conductive bottom plate of the battery cell and the thermally conductive pad to contact the upper cover cold plate, the bottom cold plate and the middle liquid cooling plate, so as to realize cooling of the bottom surface of the battery cell, thereby achieving a better cooling effect.

[0044] In addition, the liquid-cooled battery pack of the present invention is connected to a busbar insulating thermal conductive part through one side of the busbar connected to the front end pole of the battery cell. The busbar insulating thermal conductive part is contacted and connected with the battery cell thermal conductive bottom plate / the thermal conductive pad surface for heat conduction, which can further enhance the cooling effect of the battery.

[0045] The above shows and describes the basic principle and main features of the utility model and the advantages of the utility model. For those skilled in the art, it is obvious that the utility model is not limited to the details of the above exemplary embodiments, and the utility model can be implemented in other specific forms without departing from the spirit or basic features of the utility model.

[0046] Therefore, no matter from which point of view, the embodiments should be regarded as illustrative and non-restrictive, and the scope of the present invention is limited by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention.

[0047] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. Liquid-cooled battery pack, characterized in that: It includes a middle liquid cooling plate arranged in the box frame, and a layer of battery cell modules are arranged on the upper surface and the lower surface of the middle liquid cooling plate respectively, each layer of battery cell modules includes multiple columns of battery cells, and a large surface of each battery cell is opposite to the upper surface / lower surface of the middle liquid cooling plate; a battery cell heat-conducting bottom plate is arranged on the bottom surface of each column of battery cells away from the battery cell poles; each layer of battery cell modules is connected to the middle liquid cooling plate, the upper cover cold plate or the bottom cold plate through the battery cell heat-conducting bottom plate.

2. The liquid-cooled battery pack according to claim 1, characterized in that: The battery core heat-conducting bottom plate is an I-shaped structure, and the length of the battery core heat-conducting plate is adapted to the length of the battery core in the row.

3. The liquid-cooled battery pack according to claim 1, characterized in that: A thermal pad is arranged between the battery cell and the middle liquid cooling plate, the upper cover cold plate and the bottom cold plate, respectively, and the battery cell thermal conductive bottom plate is connected to the middle liquid cooling plate, the upper cover cold plate or the bottom cold plate through the thermal pad.

4. The liquid-cooled battery pack according to claim 1, characterized in that: In two adjacent columns of battery cells, the pole side of one column of battery cells is separated from the bottom surface of the other column of battery cells by the battery cell heat conductive bottom plate.

5. The liquid-cooled battery pack according to claim 1, characterized in that: An insulating heat-resistant sheet is arranged between the battery core heat-conducting bottom plate and the bottom surface of the battery core.

6. The liquid-cooled battery pack according to claim 5, characterized in that: The length of the insulating heat-resistant sheet is adapted to the length of the battery cells in the row.

7. The liquid-cooled battery pack according to claim 5, characterized in that: The battery cells in each column are bonded and fixed to the insulating heat-resistant sheet and the battery cell heat-conducting bottom plate respectively configured therein.

8. The liquid-cooled battery pack according to claim 1, characterized in that: When the pole side of the battery cell is connected to the battery cell heat conductive bottom plate, the pole of the battery cell is placed in a groove body on one side of the battery cell heat conductive bottom plate of an I-shaped structure, and a heat insulating coating is arranged on the surface of the groove body.

9. The liquid-cooled battery pack according to claim 3, characterized in that: The flat surfaces at the upper and lower ends of the I-shaped thermal conductive bottom plate of the battery cell are respectively flush with the thermal conductive pads arranged on both sides of the battery cell module, and are respectively connected to the thermal conductive pads on both sides of the battery cell module to form a thermal conductive layer structure of the battery cell module.

10. The liquid-cooled battery pack according to claim 1, characterized in that: One side of the busbar connected to the front pole of the battery cell is connected to a busbar insulating heat conductive part, and the busbar insulating heat conductive part is contacted and connected with the battery cell thermal conductive bottom plate surface for heat conduction, so as to transfer the heat of the busbar to the middle liquid cooling plate.

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