Battery cell cooling and thermal insulation sheet and power battery

Abstract

The utility model provides a cell cooling and thermal insulation sheet and a power battery, and relates to the technical field of battery thermal management, and the cell cooling and thermal insulation sheet comprises a thermal insulation layer and a cooling layer, the thermal insulation layer is used for blocking heat transfer on the two sides of the thermal insulation layer; a cooling layer is arranged on one side, close to the battery cell, of the thermal insulation layer, is made of a phase change material, is attached to the battery cell, and is used for absorbing heat emitted by the battery cell and storing the heat in a latent heat form, so that the temperature of the battery cell is reduced, and the cooling layer releases the latent heat when the battery does not work. According to the cell cooling and thermal insulation sheet and the power battery, the cooling layer is used for absorbing heat emitted by the cell and storing the heat in a latent heat form, the cooling layer releases certain latent heat when the battery does not work, and meanwhile, the thermal insulation layer is used for blocking heat transfer on the two sides of the thermal insulation layer, so that the condition that the power battery is charged and discharged for many times is handled; the cooling layer can be recycled to absorb and release heat, so that the battery is kept at a proper working temperature, and the risk of thermal runaway of the battery is reduced.

Description

Technical Field

[0001] This utility model relates to the field of battery thermal management technology, and in particular to a cell cooling insulation sheet and a power battery. Background Technology

[0002] Against the backdrop of growing global concern over issues such as climate change and the energy crisis, new energy vehicles have developed rapidly. With the improvement of energy density and fast charging capabilities of new energy batteries, how to solve the safety issues of new energy batteries is a huge challenge they face.

[0003] Currently, heat insulation sheets are commonly used in new energy batteries to prevent heat diffusion between cells. However, these sheets can only block heat transfer, not release it. Therefore, efficiently absorbing the heat generated by the cells without causing an increase in the temperature of other cells is a current technical challenge in battery thermal management. Utility Model Content

[0004] The purpose of this utility model is to provide a cell cooling and insulation sheet and a power battery to solve at least one of the above-mentioned technical problems in the prior art.

[0005] To solve the above-mentioned technical problems, this utility model provides a battery cell cooling insulation sheet, comprising: an insulation layer and a cooling layer;

[0006] The insulation layer is used to block heat transfer between the two sides of the insulation layer;

[0007] The insulation layer has a cooling layer on the side close to the battery cell. The cooling layer is made of phase change material and is attached to the battery cell to absorb the heat emitted by the battery cell and store it in the form of latent heat, thereby reducing the temperature of the battery cell. When the battery is not working, the cooling layer releases a certain amount of latent heat. The cooling layer can be recycled for absorbing and releasing heat.

[0008] Phase change materials (PCMs) are recyclable energy storage materials with high latent heat of phase change, capable of absorbing or releasing energy during phase change. PCMs can be hydrogels, paraffin wax, fatty acids, etc.

[0009] This application provides a cooling layer made of phase change material on the side of the insulation layer closest to the battery cell. The cooling layer absorbs the heat emitted by the battery cell and stores it as latent heat. When the battery is not in operation, the cooling layer releases a certain amount of latent heat. At the same time, the insulation layer blocks heat transfer between the two sides of the insulation layer. In the case of multiple charge and discharge cycles of the power battery, the cooling layer can be recycled to absorb and release heat, ensuring that the battery maintains a suitable operating temperature and reducing the risk of battery thermal runaway.

[0010] Furthermore, the cooling layer can be provided on both sides of the insulation layer.

[0011] Furthermore, a skeleton structure is provided within the cooling layer, and the skeleton structure is located on the side of the cooling layer near the insulation layer to support the cooling layer.

[0012] Furthermore, the thickness of the skeleton structure is 1 / 2 to 3 / 4 of the thickness of the cooling layer.

[0013] Furthermore, the skeleton structure is made of materials with a porous structure, such as fiber mesh or mica sheets, which can provide support.

[0014] Furthermore, the insulation layer is made of fiber material or fiber-reinforced aerogel-based composite material, with the matrix being aerogel material and the reinforcement being fiber material;

[0015] This fibrous material is a structured material formed from fibrous material with a diameter of 10~100μm through processing techniques such as doping, needle punching, weaving and bonding.

[0016] The fiber material can be one or more of glass fiber mat, ceramic fiber mat, pre-oxidized fiber mat, and alumina fiber mat.

[0017] Furthermore, a high-temperature resistant paper is provided in the middle of the insulation layer to prevent the heat of the runaway cell from spreading to adjacent cells when the cell experiences thermal runaway, thereby slowing down the spread of thermal runaway and extending the escape time for the driver and passengers after the new energy vehicle battery experiences thermal runaway.

[0018] Furthermore, the thickness of the high-temperature resistant paper is 1 / 6 to 1 / 4 of the thickness of the insulation layer.

[0019] Furthermore, the high-temperature resistant paper can be mica paper, ceramic paper, or other high-temperature resistant, fireproof, and insulating materials.

[0020] Furthermore, the battery cell cooling insulation sheet also includes a waterproof and breathable membrane. The insulation layer is encapsulated within the waterproof and breathable membrane. The waterproof and breathable membrane serves to waterproof and allow the insulation layer to breathe. It blocks liquid molecules generated during the phase change of the cooling layer, preventing them from passing through the membrane and entering the insulation layer, thereby improving the performance and service life of the insulation layer.

[0021] Preferably, the waterproof and breathable membrane is made of waterproof and breathable materials such as polytetrafluoroethylene and thermoplastic polyurethane, which typically have good waterproof and breathable properties.

[0022] Furthermore, the cell cooling insulation sheet also includes an outer encapsulation film, which is disposed on the outer surface of the cell cooling insulation sheet for encapsulating the cell cooling insulation sheet.

[0023] Preferably, the outer packaging film can be an aluminum-plastic film, polyester film, polyamide film, or polyolefin film, etc., which are packaging films with good plasticity.

[0024] Preferably, the thickness of the cell cooling insulation sheet is 0.6~5mm.

[0025] Preferably, the total thickness of the two cooling layers is 0.3~3mm.

[0026] Preferably, the thickness of the insulation layer is 0.3~2mm.

[0027] Secondly, based on the same technical concept, this utility model also provides a power battery including the cell cooling and insulation sheet as described above, and also includes several cells;

[0028] A plurality of the aforementioned battery cells and a plurality of the aforementioned battery cell cooling and insulation sheets are arranged alternately;

[0029] The cell cooling and insulation sheet is disposed between two adjacent cells. The two cooling layers of the cell cooling and insulation sheet are respectively attached to the two adjacent cells. The cooling layers are used to absorb the heat of the cells and to block the heat transfer between the two adjacent cells through the insulation layers of the cell cooling and insulation sheet.

[0030] To address the issue of numerous charge-discharge cycles in the power battery, when the power battery is in operation, the cooling layer made of phase change material absorbs the heat emitted by adjacent battery cells and stores it as latent heat, thereby reducing the temperature of the battery cells. When the power battery is not in operation, the cooling layer releases a certain amount of latent heat, thus recycling the heat absorption and release of the cooling layer to ensure that the power battery maintains a suitable operating temperature and reduces the risk of thermal runaway of the power battery.

[0031] By adopting the above technical solution, this utility model has the following beneficial effects:

[0032] This utility model provides a cell cooling insulation sheet and a power battery. The cooling layer absorbs the heat emitted by the cell and stores it in the form of latent heat. When the battery is not working, the cooling layer releases a certain amount of latent heat. At the same time, the insulation layer blocks the heat transfer between the two sides of the insulation layer. In the case of multiple charge and discharge cycles of the power battery, the cooling layer can be recycled to absorb and release heat, ensuring that the battery maintains a suitable operating temperature and reducing the risk of battery thermal runaway. Attached Figure Description

[0033] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in 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 utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0034] Figure 1 This is a schematic diagram of the structure of the battery cell cooling and insulation sheet provided in an embodiment of the present utility model;

[0035] Figure 2 for Figure 1 The diagram shows the structure of the cooling layer.

[0036] Figure 3 for Figure 1 The diagram shows the structure of the insulation layer.

[0037] Figure 4 A graph showing the change of cold surface temperature over time in a simulated thermal runaway environment of a battery cell cooling insulation sheet provided in this embodiment of the utility model.

[0038] Figure 5 A schematic diagram of the cell module structure of the power battery provided in this embodiment of the utility model;

[0039] Figure 6 This is a schematic diagram of the cell module structure of a power battery provided in another embodiment of the present invention.

[0040] Figure label:

[0041] 101-Cooling layer; 102-Skeleton structure; 103-Insulation layer; 104-High temperature resistant paper; 105-Waterproof and breathable membrane; 106-Outer encapsulation film; 201-Cell cooling and insulation sheet; 202-Cell. Detailed Implementation

[0042] The technical solution of this utility model will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0043] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model 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, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0044] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" 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 of 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.

[0045] The present invention will be further explained below with reference to specific embodiments.

[0046] It should also be noted that the specific embodiments or implementation methods described below are a series of optimized settings listed by this utility model to further explain the specific utility model content, and these settings can be combined or used in conjunction with each other.

[0047] Example 1

[0048] like Figure 1-4 As shown, this embodiment provides a battery cell cooling and insulation sheet, including: an insulation layer 103 and a cooling layer 101; the insulation layer 103 is used to block heat transfer between the two sides of the insulation layer 103; the insulation layer 103 has a cooling layer 101 on the side close to the battery cell, the cooling layer 101 is made of phase change material, is attached to the battery cell, and is used to absorb the heat emitted by the battery cell and store it in the form of latent heat, thereby reducing the temperature of the battery cell. When the battery is not working, the cooling layer 101 releases a certain amount of latent heat, and the cooling layer 101 can be recycled for heat absorption and release; wherein, the phase change material is a recyclable energy storage material with high latent heat of phase change, which can absorb or release energy during the phase change process. In this embodiment, the phase change material can be hydrogel, paraffin, fatty acid, etc. When the temperature rises, the phase change material such as hydrogel undergoes a phase change, and some materials will melt into a liquid state, or even further vaporize into a gas state.

[0049] The recyclability of the cooling layer 101 made of phase change material was verified by a thermal shock test. The temperature was lowered to -40°C and held for 0.5 hours, then raised to 85°C within 30 minutes and held for 0.5 hours. This was repeated 1000 times. The test results showed that the cooling layer 101 did not lose water, thus proving the recyclability of the cooling layer 101.

[0050] This application provides a cooling layer 101 made of phase change material on the side of the insulation layer 103 near the battery cell. The cooling layer 101 absorbs the heat emitted by the battery cell and stores it as latent heat. When the battery is not working, the cooling layer 101 releases a certain amount of latent heat. At the same time, the insulation layer 103 blocks the heat transfer between the two sides of the insulation layer 103. In the case of multiple charge and discharge cycles of the power battery, the cooling layer 101 can be recycled to absorb and release heat, ensuring that the battery maintains a suitable operating temperature and reducing the risk of battery thermal runaway.

[0051] Reference Figure 1 As shown, based on the above technical solution, and further preferably, the cooling layer 101 is provided on both sides of the insulation layer 103.

[0052] Furthermore, a skeleton structure 102 is provided inside the cooling layer 101. The skeleton structure 102 is located on the side of the cooling layer 101 near the heat insulation layer 103 and is used to support the cooling layer 101.

[0053] Reference Figure 2 As shown, more preferably, the thickness of the skeleton structure 102 is 1 / 2 to 3 / 4 of the thickness of the cooling layer 101.

[0054] In this embodiment, the skeleton structure 102 is made of a material with a porous structure, such as fiber mesh or mica sheet, which can provide support.

[0055] Furthermore, the insulation layer 103 is made of fiber material or fiber-reinforced aerogel-based composite material, with the matrix being aerogel material and the reinforcement being fiber material; the fiber material is a structured material formed by processing fibrous material with a diameter of 10~100μm through doping, needle punching, weaving and bonding processes; wherein, the fiber material can be one or more of glass fiber felt, ceramic fiber felt, pre-oxidized fiber felt and alumina fiber felt.

[0056] Similarly, the performance of the thermal insulation layer 103 was verified by a thermal shock test; the temperature was lowered to -40°C and held for 0.5 h, and then raised to 85°C within 30 min and held for 0.5 h, which constituted one cycle. This cycle was repeated 1000 times. The test results showed that the performance of the thermal insulation layer 103 did not change.

[0057] Reference Figure 3 As shown, in a further preferred embodiment, a high-temperature resistant paper 104 is disposed in the middle of the thermal insulation layer 103, which is used to prevent the heat of the runaway cell from spreading to adjacent cells when the cell is thermally runaway, thereby slowing down the spread of thermal runaway and extending the escape time for the driver and passengers after the new energy vehicle battery is thermally runaway.

[0058] More preferably, the thickness of the high-temperature resistant paper 104 is 1 / 6 to 1 / 4 of the thickness of the insulation layer 103.

[0059] More preferably, the high-temperature resistant paper 104 can be mica paper, ceramic paper, or other high-temperature resistant, fireproof, and insulating materials.

[0060] Reference Figure 4 As shown, the temperature change of the cold surface of the cell cooling insulation sheet over time was tested by simulating a thermal runaway environment of the battery cell. The cooling and insulation effects of the cell cooling insulation sheet with and without the high-temperature resistant paper 104 were compared. The test results show that the cell cooling insulation sheet with the high-temperature resistant paper 104 has better cooling and insulation effects.

[0061] Furthermore, the cell cooling insulation sheet also includes a waterproof and breathable membrane 105. The insulation layer 103 is encapsulated within the waterproof and breathable membrane 105. The waterproof and breathable membrane 105 is used for waterproofing and breathability of the insulation layer 103. The waterproof and breathable membrane 105 blocks the liquid molecules generated by the phase change of the cooling layer 101, preventing the liquid molecules generated by the phase change of the cooling layer 101 from passing through the waterproof and breathable membrane 105 into the insulation layer 103, thereby improving the performance and service life of the insulation layer 103.

[0062] More preferably, the waterproof and breathable membrane 105 is made of waterproof and breathable materials such as polytetrafluoroethylene and thermoplastic polyurethane, which typically have good waterproof and breathable properties.

[0063] Furthermore, the cell cooling insulation sheet also includes an outer encapsulation film 106, which is disposed on the outer surface of the cell cooling insulation sheet for encapsulating the cell cooling insulation sheet.

[0064] More preferably, the outer packaging film 106 can be an aluminum-plastic film, polyester film, polyamide film or polyolefin film, etc., which are packaging films with good plasticity.

[0065] In this embodiment, the thickness of the cell cooling insulation sheet is 0.6~5mm.

[0066] More preferably, the total thickness of the two cooling layers 101 is 0.3~3mm.

[0067] Furthermore, the thickness of the insulation layer 103 is 0.3~2mm.

[0068] In the event of thermal runaway in a battery cell, the cooling layer 101, made of phase change material, can rapidly absorb heat and then vaporize, while the insulation layer 103 prevents heat from being transferred to adjacent battery cells.

[0069] This invention utilizes a cooling layer 101 to absorb the heat emitted by the battery cell and store it as latent heat. When the battery is not in operation, the cooling layer 101 releases a certain amount of latent heat. At the same time, the insulation layer 103 blocks heat transfer between its two sides. In the case of multiple charge and discharge cycles of the power battery, the cooling layer 101 can be recycled to absorb and release heat, ensuring that the battery maintains a suitable operating temperature and reducing the risk of battery thermal runaway. The insulation layer 103 and the cooling layer 101 are sealed and fixed by an outer encapsulation film 106, which is simple, convenient, safe and reliable.

[0070] Example 2

[0071] like Figure 5-6 As shown, this embodiment provides a power battery including the cell cooling and insulation sheet 201 as described above, and further includes a plurality of cells 202; the plurality of cells 202 and the plurality of cell cooling and insulation sheets 201 are alternately arranged to form a cell 202 module; the cell cooling and insulation sheet 201 is disposed between two adjacent cells 202, and the two cooling layers 101 of the cell cooling and insulation sheet 201 are respectively attached to two adjacent cells 202 for absorbing the heat of the cells 202 through the cooling layers 101 and blocking the heat transfer between two adjacent cells 202 through the insulation layer 103 of the cell cooling and insulation sheet 201;

[0072] To address the issue of numerous charge-discharge cycles in the power battery, when the power battery is in operation, the cooling layer 101, made of phase change material, absorbs the heat emitted by the adjacent battery cells 202 and stores it as latent heat, thereby reducing the temperature of the battery cells 202. When the power battery is not in operation, the cooling layer 101 releases a certain amount of latent heat, thus recycling the heat absorption and release of the cooling layer 101 to ensure that the power battery maintains a suitable operating temperature and reduces the risk of thermal runaway of the power battery.

[0073] Reference Figure 6 As shown, in one feasible embodiment, the battery cell 202 is provided on one side of the battery cell cooling insulation sheet 201, and the battery cell 202 is not provided on the other side. The cooling layer 101 is only provided on the side close to the battery cell 202.

[0074] The cell cooling and insulation sheet 201 described in this application does not require mechanical connection with the adjacent cell 202, making it safe and reliable.

[0075] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although the utility model 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 utility model.

Claims

1. A cell cooling and insulation sheet, characterized in that, include: Insulation layer and cooling layer; The insulation layer is used to block heat transfer between the two sides of the insulation layer; The insulation layer has a cooling layer on the side close to the battery cell. The cooling layer is made of phase change material and is attached to the battery cell to absorb the heat emitted by the battery cell and store it in the form of latent heat, thereby reducing the temperature of the battery cell. When the battery is not working, the cooling layer releases the latent heat.

2. The cell cooling and temperature insulation sheet according to claim 1, wherein The cooling layer is provided on both sides of the insulation layer.

3. The cell cooling and temperature insulation sheet according to claim 1, wherein The cooling layer is provided with a skeleton structure, which is located on the side of the cooling layer near the insulation layer to support the cooling layer.

4. The cell cooling and temperature insulation sheet according to claim 3, characterized by The thickness of the skeleton structure is 1 / 2 to 3 / 4 of the thickness of the cooling layer; The skeletal structure is made of fiber mesh or mica sheets.

5. The cell cooling and temperature insulation sheet according to claim 1, wherein A high-temperature resistant paper is placed in the middle of the insulation layer to prevent the heat from the runaway cell from spreading to adjacent cells in the event of thermal runaway.

6. The cell cooling and temperature insulation sheet according to claim 5, wherein The thickness of the high-temperature resistant paper is 1 / 6 to 1 / 4 of the thickness of the insulation layer; The high-temperature resistant paper is mica paper or ceramic paper.

7. The cell cooling and temperature insulation sheet according to claim 1, wherein The cell cooling insulation sheet also includes a waterproof and breathable membrane, and the insulation layer is encapsulated within the waterproof and breathable membrane. The waterproof and breathable membrane serves to provide waterproofing and breathability for the insulation layer.

8. The cell cooling and temperature insulation sheet according to claim 1, wherein The cell cooling insulation sheet also includes an outer encapsulation film, which is disposed on the outer surface of the cell cooling insulation sheet and is used for encapsulating the cell cooling insulation sheet.

9. A power battery comprising the temperature-reducing and insulation sheet for an electric core according to any one of claims 1 to 8, characterized in that, Also includes: It also includes several battery cells; A plurality of the aforementioned battery cells and a plurality of the aforementioned battery cell cooling and insulation sheets are arranged alternately; The cell cooling insulation sheet is disposed between two adjacent cells. The two cooling layers of the cell cooling insulation sheet are respectively attached to the two adjacent cells. The cooling layers are used to absorb the heat of the cells and to block the heat transfer between the two adjacent cells through the insulation layers of the cell cooling insulation sheet.

Images