Battery pack insulation structure and battery pack

Abstract

This utility model belongs to the field of battery pack technology and discloses a battery pack insulation structure and a battery pack. In the battery pack insulation structure, at least one end cell is provided with a heat source between it and the fixed frame. The heat source can generate heat to heat the adjacent end cell. Thus, during the insulation process when the battery pack is stationary, the temperature of the end cell can be prevented from dropping too quickly, and the temperature difference between the end cell and the cells in other positions can be reduced. Furthermore, during the heating process of the battery pack, the small temperature difference between the end cell and the cells in other positions can prevent the temperature of the end cell from rising too much, thereby increasing the service life of the battery pack. In addition, in low-temperature environments, the heat source can also play an auxiliary heating role, enabling the temperature of the battery pack to rise rapidly and improving the charging and discharging efficiency of the battery pack.

Description

Technical Field

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

[0002] In a CTP (Cell To Pack) battery pack, the cells are directly integrated with the fixed beam, reducing the use of end plates and separators and improving the overall integrity. Specifically, there is only one insulation layer between the fixed beam and the cells. To ensure the heat dissipation of the battery pack, the fixed beam is generally made of aluminum alloy, which has high thermal conductivity. The heat from the cells can be quickly conducted to the fixed beam, which is beneficial for cooling the battery pack.

[0003] However, during the battery's static heat preservation process, the temperature of the cells near the fixed beam drops faster, while the temperature of the cells far from the fixed beam and located in the middle drops slower. This results in a large temperature difference between the cells near and far from the fixed beam. During the heating process, the temperature of the cells near the fixed beam rises rapidly, leading to a large temperature fluctuation in the cells near the fixed beam. All of these factors can reduce the battery pack's lifespan. Utility Model Content

[0004] According to one aspect of the present invention, the present invention provides a battery pack insulation structure to solve the problem in the prior art that the battery pack life is reduced due to the large temperature difference between the battery cells near the fixed beam and the battery cells far from the fixed beam, or the large temperature variation of the battery cells near the fixed beam.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A battery pack insulation structure is used to be installed inside the fixed frame of the battery pack. The fixed frame is also provided with a cell group, which includes multiple cells arranged sequentially along a first direction. Among the multiple cells, the cells located at both ends along the first direction are end cells.

[0007] At least one of the end cells is provided with a heat source between it and the fixed frame, the heat source being capable of generating heat to heat the adjacent end cells.

[0008] As a preferred embodiment of the battery pack insulation structure, it also includes an insulation layer, which is disposed between the heat source and the fixed frame.

[0009] As a preferred embodiment of the battery pack insulation structure, two heat sources are provided, which are respectively located at both ends of the battery cell assembly, and the two heat sources can respectively heat the two end cells located at both ends.

[0010] As a preferred embodiment of the battery pack insulation structure, the heat source is used to be electrically connected to the battery cell assembly, and the battery cell assembly is used to supply power to the heat source.

[0011] As a preferred embodiment of the battery pack insulation structure, the heat source is also equipped with a temperature sensor, which is used to obtain the temperature of the end cell adjacent to it.

[0012] According to another aspect of the present invention, a battery pack is provided, including the above-mentioned battery pack insulation structure, a fixing frame, and a cell assembly. The battery pack insulation structure and the cell assembly are both disposed inside the fixing frame. The cell assembly includes a plurality of cells, which are arranged sequentially along a first direction.

[0013] As a preferred embodiment of the battery pack, the battery cell has two contact surfaces arranged parallel to and opposite to each other along a first direction and four sidewalls located between the two contact surfaces, wherein one of the contact surfaces is directly opposite the heat source, and the area of ​​any of the sidewalls is smaller than the area of ​​the contact surface.

[0014] As a preferred embodiment of the battery pack, along the first direction, the projection of the battery cell falls within the projection range of the heat source.

[0015] As a preferred embodiment of the battery pack, the battery cell group is provided in multiple ways, and the multiple battery cell groups are spaced apart along a second direction, which is perpendicular to the first direction. The heat source can simultaneously heat the end cells of the multiple battery cell groups.

[0016] As a preferred embodiment of the battery pack, along the second direction, the cells of the cell group located at both ends are spaced apart from the fixed frame.

[0017] The beneficial effects of this utility model are:

[0018] This utility model provides a battery pack insulation structure for installation inside a fixed frame of the battery pack. The fixed frame also houses a battery cell assembly, which includes multiple cells arranged sequentially along a first direction. The cells located at both ends along the first direction are designated as end cells. At least one end cell is connected to the fixed frame by a heat source capable of generating heat to heat adjacent end cells. This prevents the end cells from cooling down too quickly during the battery pack's static insulation process, minimizing the temperature difference between the end cells and other cells. Furthermore, during battery pack heating, the smaller temperature difference between the end cells and other cells prevents excessive temperature increases in the end cells, thereby extending the battery pack's lifespan. In addition, in low-temperature environments, the heat source provides auxiliary heating, rapidly increasing the battery pack's temperature and improving its charging and discharging efficiency.

[0019] This utility model also provides a battery pack, including a battery pack insulation structure, a fixing frame, and a cell assembly. Both the insulation structure and the cell assembly are housed inside the fixing frame. The cell assembly includes multiple cells arranged sequentially along a first direction. By incorporating a heat source, the battery pack insulation structure prevents the temperature of the end cells from dropping too quickly during the static insulation process, minimizing the temperature difference between the end cells and cells in other locations. Furthermore, during the heating process, the smaller temperature difference between the end cells and other cells prevents excessive temperature increases in the end cells, thereby increasing the battery pack's lifespan. In addition, in low-temperature environments, the heat source can also provide auxiliary heating, rapidly increasing the battery pack's temperature and improving its charging and discharging efficiency. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the battery pack insulation structure in an embodiment of this utility model;

[0021] Figure 2 yes Figure 1 Enlarged view of point A in the middle;

[0022] Figure 3 This is a top view schematic diagram of the battery pack insulation structure in an embodiment of this utility model;

[0023] Figure 4 yes Figure 3 Enlarged view of point B in the middle.

[0024] In the picture:

[0025] 1. Fixed frame;

[0026] 2. Battery cell assembly; 21. Battery cell;

[0027] 3. Heat source;

[0028] 4. Insulation layer. Detailed Implementation

[0029] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, not the entire structure.

[0030] In the description of this utility model, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; 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; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0031] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0032] In the description of this embodiment, the terms "upper," "lower," "left," and "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, 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 utility model. In addition, the terms "first" and "second" are only used for distinction in description and have no special meaning.

[0033] In CTP (Cell-to-Pack) battery packs, there is typically only one insulation layer between the fixed beam and the battery cells. However, during the battery's static insulation process, the temperature of the cells near the fixed beam drops faster, while the temperature of the cells far from the fixed beam and located in the middle drops slower. This results in a large temperature difference between the cells near and far from the fixed beam. During the heating process, the temperature of the cells near the fixed beam rises rapidly, leading to a large temperature fluctuation in the cells near the fixed beam. All of these factors can reduce the lifespan of the battery pack.

[0034] In response, this embodiment provides a battery pack insulation structure to solve the problem in the prior art where the battery pack life is reduced due to the large temperature difference between the cells near the fixed beam and the cells far from the fixed beam, or the large temperature variation of the cells near the fixed beam. It can be used in the field of battery pack technology, specifically in CTP structure battery packs, and in other embodiments, it can also be used in other types or structures of battery packs.

[0035] Reference Figures 1-4The battery pack insulation structure is installed inside the fixed frame 1 of the battery pack. Inside the fixed frame 1, a cell assembly 2 is also installed. The cell assembly 2 includes multiple cells 21, which are arranged along a first direction (the first direction being...). Figure 1 or Figure 3 The cells 21 are arranged sequentially along the CD direction, and the cells 21 located at both ends along the first direction are the end cells. At least one end cell is provided with a heat source 3 between itself and the fixed frame 1. The heat source 3 can generate heat to heat the adjacent end cells. This prevents the temperature of the end cells from dropping too quickly during the heat preservation process of the battery pack, thus reducing the temperature difference between the end cells and other cells 21. During the heating process of the battery pack, the small temperature difference between the end cells and other cells 21 prevents the temperature of the end cells from rising too much, thereby increasing the service life of the battery pack. In addition, in low-temperature environments, the heat source 3 can also play an auxiliary heating role, allowing the temperature of the battery pack to rise rapidly and improving the charging and discharging efficiency of the battery pack.

[0036] Continue to refer to Figures 1-4 The battery pack insulation structure also includes an insulation layer 4, which is placed between the heat source 3 and the fixed frame 1. It can provide a certain insulation effect, prevent the temperature of the battery cell 21 from dropping too quickly, and also prevent the heat emitted by the heat source 3 from dissipating too quickly during the process of the heat source 3 heating the battery cell 21, thereby improving the heating effect. Optionally, the insulation layer 4 is foam.

[0037] Continue to refer to Figures 1-4 There are two heat sources 3, which are respectively located at both ends of the battery cell assembly 2. The two heat sources 3 can heat the two end cells located at both ends, thereby preventing the temperature of the two end cells located at both ends of the battery cell assembly 2 from dropping too quickly. Optionally, there are also two insulation layers 4, with the two heat sources 3 located between the two insulation layers 4, that is, both insulation layers 4 are located at the end of the heat source 3 away from the battery cell assembly 2.

[0038] Continue to refer to Figures 1-4 Heat source 3 is used to electrically connect with battery cell assembly 2, and battery cell assembly 2 is used to supply power to heat source 3, thereby further simplifying the electrical connection structure of heat source 3.

[0039] As an alternative, the power supply for the heat source 3 can also be built into the heat source 3, so that the heat source 3 does not need to be electrically connected to the cell group 2, which can further simplify the overall structure of the battery pack, but will increase the structural complexity of the heat source 3.

[0040] Optionally, the heat source 3 is also equipped with a temperature sensor. The temperature sensor is used to acquire the temperature of the adjacent end cells, and the on / off state of the heat source 3 can be controlled based on the temperature of the adjacent end cells acquired by the temperature sensor. Specifically, in this embodiment, the temperature acquired by the temperature sensor can be compared with the temperature of other cells 21 acquired by the BMS (Battery Management System), and the difference between the two can be calculated to determine the temperature. If the temperature acquired by the temperature sensor on the heat source 3 is more than 2°C lower than the temperature of other cells 21 acquired by the BMS, heating is activated; if the temperature acquired by the temperature sensor on the heat source 3 is more than 5°C higher than the temperature of other cells 21 acquired by the BMS, heating is deactivated.

[0041] This embodiment also provides a battery pack, specifically adopting a CTP structure. The battery pack includes a battery pack insulation structure, a fixing frame 1, and a cell assembly 2. Both the battery pack insulation structure and the cell assembly 2 are disposed inside the fixing frame 1. The cell assembly 2 includes multiple cells 21 arranged sequentially along a first direction. The battery pack insulation structure, by incorporating a heat source 3, prevents the temperature of the end cells from dropping too quickly during the battery pack's static insulation process, thus minimizing the temperature difference between the end cells and other cells 21. Furthermore, during the battery pack's heating process, the small temperature difference between the end cells and other cells 21 prevents excessive temperature increases in the end cells, thereby increasing the battery pack's lifespan. In addition, in low-temperature environments, the heat source 3 provides auxiliary heating, rapidly increasing the battery pack's temperature and improving its charging and discharging efficiency. The fixing frame 1 is made of aluminum alloy to provide excellent thermal conductivity.

[0042] Continue to refer to Figures 1-4 In this embodiment, the battery cell 21 is a square battery cell. Specifically, the battery cell 21 has two contact surfaces arranged parallel to and opposite to each other along a first direction, and four sidewalls located between the two contact surfaces. One of the contact surfaces is directly opposite the heat source 3. The area of ​​any sidewall is smaller than the area of ​​the contact surface. This arrangement ensures that the side surface of the battery cell 21 with the largest area is directly opposite the heat source 3, facilitating heating of the battery cell 21 by the heat source 3. In other embodiments, the battery cell 21 can also be a cylindrical battery cell. In this case, the heat source 3 can be located at any angle on the outer peripheral wall of the battery cell 21.

[0043] Continue to refer to Figures 1-4 Along the first direction, the projection of the battery cell 21 falls within the projection range of the heat source 3, thereby heating the entire contact surface of the battery cell 21 facing the heat source 3, making the battery cell 21 heated evenly. Optionally, the heat source 3 is in the form of a sheet and is attached to one of the contact surfaces of the battery cell 21.

[0044] Continue to refer to Figures 1-4 Multiple battery cell groups 2 are provided, and the multiple battery cell groups 2 are spaced apart along a second direction, which is perpendicular to the first direction (the second direction is...). Figure 1 or Figure 3 The EF direction in the battery pack allows for the arrangement of more cells 21 to increase the energy density of the battery pack. In addition, the heat source 3 can simultaneously heat the end cells of multiple cell groups 2, thereby ensuring that the temperature of the cells 21 in multiple cell groups 2 remains consistent.

[0045] Continue to refer to Figures 1-4 Along the second direction, the battery cells 21 at both ends of the battery cell group 2 are spaced apart from the fixed frame 1 to provide a certain heat insulation effect between the battery cells 21 and the fixed frame 1, thereby preventing heat from being conducted to the fixed frame 1 along the second direction. Furthermore, it is understood that since the battery cells 21 in the battery cell group 2 are arranged sequentially along the first direction, even if the heat from multiple battery cells 21 is simultaneously conducted to the fixed frame 1 along the second direction, there will be no significant temperature difference between the multiple battery cells 21 in the same battery cell group 2.

[0046] Obviously, the above embodiments of this utility model are merely examples for clearly illustrating the present utility model, and are not intended to limit the implementation of the present utility model. Those skilled in the art can make various obvious changes, readjustments, and substitutions without departing from the protection scope of this utility model. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the protection scope of the claims of this utility model.

Claims

1. A battery pack thermal retention structure, characterized by, Used to be set inside the fixing frame (1) of the battery pack, the fixing frame (1) is also provided with a cell group (2), the cell group (2) includes a plurality of cells (21), the plurality of cells (21) are arranged sequentially along a first direction, and among the plurality of cells (21), the cells (21) located at both ends along the first direction are end cells; At least one of the end cells is provided with a heat source (3) between it and the fixed frame (1), the heat source (3) being able to generate heat to heat the end cell adjacent to it.

2. The battery pack thermal management structure of claim 1, wherein, It also includes a heat insulation layer (4), which is used to be disposed between the heat source (3) and the fixed frame (1).

3. The battery pack thermal management structure of claim 1, wherein, There are two heat sources (3), which are respectively located at both ends of the battery cell assembly (2), and the two heat sources (3) can respectively heat the two end battery cells located at both ends.

4. The battery pack thermal management structure of claim 1, wherein, The heat source (3) is used to be electrically connected to the battery cell assembly (2), and the battery cell assembly (2) is used to supply power to the heat source (3).

5. The battery pack thermal management structure of any one of claims 1-4, wherein, The heat source (3) is also equipped with a temperature sensor, which is used to obtain the temperature of the end cell adjacent to it.

6. A battery pack, characterized in that, The battery pack insulation structure as described in any one of claims 1-5 further includes a fixed frame (1) and a cell assembly (2), wherein the battery pack insulation structure and the cell assembly (2) are both disposed inside the fixed frame (1), and the cell assembly (2) includes a plurality of cells (21), which are arranged sequentially along a first direction.

7. The battery pack according to claim 6, characterized in that, The battery cell (21) has two contact surfaces arranged parallel to each other along a first direction and four sidewalls located between the two contact surfaces, one of the contact surfaces being directly opposite the heat source (3), and the area of ​​any of the sidewalls being smaller than the area of ​​the contact surface.

8. The battery pack according to claim 6, characterized in that, Along the first direction, the projection of the battery cell (21) falls within the projection range of the heat source (3).

9. The battery pack according to claim 6, characterized in that, The battery cell group (2) is provided in multiple ways, and the multiple battery cell groups (2) are spaced apart along a second direction, which is perpendicular to the first direction. The heat source (3) can simultaneously heat the end cells of the multiple battery cell groups (2).

10. The battery pack according to claim 9, characterized in that, Along the second direction, the cells (21) of the cell group (2) located at both ends are spaced apart from the fixed frame (1).

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