A battery thermal management device

Abstract

The utility model provides a kind of battery thermal management device, temperature-sensitive gas production structural member is provided in the battery thermal management device;Temperature-sensitive gas production structural member is solid under the condition that monomer battery normal work and does not contact with monomer battery inner electrolyte, will not produce any influence to the electrochemical performance of monomer battery and battery pack;And when monomer battery is in fault state, battery shell or aluminium plastic film temperature rises to the threshold set, temperature-sensitive gas production structural member changes from solid to gaseous, which can quickly improve the pressure in battery shell or aluminium plastic film, when the pressure in battery shell or aluminium plastic film is greater than the threshold set, high pressure will rush off pressure relief valve, break safety valve or aluminium plastic film, form pressure relief channel, bring out high-temperature material in battery shell or aluminium plastic film from battery shell or aluminium plastic film to reduce the temperature inside battery shell or aluminium plastic film, reach the purpose of battery thermal management.

Description

Technical Field

[0001] This utility model relates to the field of battery energy storage thermal management technology, and in particular to a battery thermal management device. Background Technology

[0002] Thermal runaway is the most significant safety hazard in lithium-ion battery applications, and there is currently no effective solution. The only current solution is to find a suitable structural design that allows a single cell to spontaneously combust when thermal runaway occurs, preventing it from spreading to other cells and thus avoiding an escalation of the fire.

[0003] With the government's encouragement of the use of green electricity, energy storage technology is being applied more and more widely. Under this trend, battery pack capacities are becoming larger and larger. However, thermal management of large-capacity battery packs is crucial and challenging. It is difficult to design a suitable cell placement structure to ensure that thermal runaway combustion of one individual cell will not affect other individual cells. Therefore, how to prevent thermal runaway combustion of individual cells is a pressing problem that needs to be solved. Utility Model Content

[0004] To address the shortcomings of existing technologies, this invention provides a battery thermal management device. This device can dissipate heat from individual cells before they experience thermal runaway combustion, thus preventing the battery pack from burning by releasing heat from the individual cells in advance, achieving the purpose of battery thermal management. The device is highly efficient and safe to use, effectively preventing the battery pack from burning.

[0005] The objective of this utility model is achieved through the following technical solution:

[0006] A battery thermal management device includes: a battery casing, a battery cell, and a temperature-sensitive gas-generating structure; the battery casing is provided with a positive terminal post, a negative terminal post, a pressure relief valve or a safety valve; the battery cell includes a positive electrode plate, a negative electrode plate, a positive electrode tab, a negative electrode tab, and a separator;

[0007] The battery cell is disposed inside the battery casing; the battery casing is filled with electrolyte, which wets the battery cell; the positive electrode is connected to the positive terminal through a positive electrode tab, and the negative electrode is connected to the negative terminal through a negative electrode tab;

[0008] The temperature-sensitive gas-generating structure is located between the positive electrode tab and the negative electrode tab; or, the temperature-sensitive gas-generating structure is located at the bottom inner side of the battery casing.

[0009] A battery thermal management device includes: an aluminum-plastic film, a battery cell, and a temperature-sensitive gas-generating structure; a positive electrode foil and a negative electrode foil are disposed on the aluminum-plastic film; the battery cell includes a positive electrode sheet, a negative electrode sheet, a positive electrode tab, a negative electrode tab, and a separator.

[0010] The battery cell is disposed inside the aluminum-plastic film; the aluminum-plastic film is filled with electrolyte, which wets the battery cell; the positive electrode is connected to the positive electrode foil through a positive electrode tab, and the negative electrode is connected to the negative electrode foil through a negative electrode tab; the aluminum-plastic film includes a top sealing edge, a side sealing edge, a folded edge, and a second sealing edge; the side sealing edge and the top sealing edge are adjacent to the folded edge, and the side sealing edge and the second sealing edge are opposite to each other;

[0011] The temperature-sensitive gas-generating structure is located between the aluminum-plastic film and the battery cell, near the second sealing edge of the aluminum-plastic film.

[0012] According to the embodiment of this utility model, the second sealing edge of the aluminum-plastic film is located near the air bladder of the aluminum-plastic film.

[0013] According to an embodiment of the present invention, the diaphragm is disposed between the positive electrode and the negative electrode.

[0014] According to an embodiment of this utility model, the pressure relief valve or safety valve is disposed between the positive terminal and the negative terminal.

[0015] According to an embodiment of this utility model, the temperature-sensitive gas-generating structure includes a temperature-sensitive gas-generating material and a packaging film, wherein the packaging film is disposed on the outer surface of the temperature-sensitive gas-generating material.

[0016] According to an embodiment of this utility model, the packaging film is selected from at least one of polyethylene heat-sealing film, polypropylene heat-sealing film, polyester heat-sealing film, or aluminum-plastic packaging film.

[0017] According to the embodiments of this utility model, the thickness of the packaging film is 10-100μm, for example, 15μm, 20μm, 25μm, 30μm, 35μm, 40μm, 50μm, 60μm, 70μm, 80μm, 90μm or 100μm.

[0018] According to the embodiments of this utility model, the shape of the temperature-sensitive gas-generating structure is rectangular, square, circular, elliptical, or other shapes.

[0019] According to the embodiments of this utility model, the thickness of the temperature-sensitive gas-generating structure is 0.05-50mm, for example, 0.05mm, 0.1mm, 0.2mm, 0.5mm, 0.8mm, 1mm, 2mm, 5mm, 8mm, 10mm, 15mm, 20mm, 25mm, 30mm, 40mm or 50mm.

[0020] According to the embodiment of this utility model, the mass of the temperature-sensitive gas-generating material in the temperature-sensitive gas-generating structure is 0.1-10g, preferably 0.3-5g, such as 0.5-3g, such as 1g or 2g.

[0021] According to the embodiments of this utility model, the temperature-sensitive gas-generating material is selected from at least one of N,N′-dimethylN,N′-dinitrosylterephthalamide, 4,4′-oxobis(benzenesulfonylhydrazine), 3,3′-disulfonylhydrazine diphenyl sulfone, 1,3-benzenedisulfonylhydrazine, and p-toluenesulfonylhydrazine.

[0022] According to the embodiment of this utility model, the gas generation temperature of the temperature-sensitive gas-generating material is 100-140℃.

[0023] According to an embodiment of this utility model, the temperature-sensitive gas-generating structure can operate at temperatures below 90°C. o At temperature C, the material is stable and does not produce any gas; when heated to above 100°C (e.g., 100-140°C), the temperature-sensitive gas-generating structure generates more than 100 times its own volume of gas; when the temperature-sensitive gas-generating structure is used in lithium-ion batteries, it is packaged separately so that it does not directly contact the electrolyte in the cell, thus not affecting the battery's cycle performance; when the battery's thermal runaway temperature rises, it can rapidly release a large amount of inert gas in the cell, and the resulting pressure causes the pressure relief valve of the battery casing to open, the safety valve to break, or the aluminum-plastic film to break, releasing flammable organic solvent vapors and carrying away heat, reducing the risk of fire and explosion of individual cells and battery packs.

[0024] The inventors of this application, through research, also discovered that the most significant safety issue with lithium-ion batteries is when the temperature rises to 140°C. o After temperature C, the separator will melt, causing a large-area short circuit, which will lead to thermal runaway of the battery, resulting in fire and explosion. The gas generation temperature of the temperature-sensitive gas-generating material in this application is 100-140°C. o C. Within this temperature range, the separator has not yet melted over a large area. That is, before the separator melts over a large area, the temperature-sensitive gas-generating material will generate a large amount of gas. This gas will break through the pressure relief valve, the safety valve, or the aluminum-plastic film, forming a pressure relief channel, releasing high-temperature hot steam and carrying away heat, thus preventing the battery from reaching the flash point of the electrolyte solvent. This fundamentally improves the safety of the individual battery and achieves the purpose of battery thermal management.

[0025] According to the embodiment of this utility model, the temperature-sensitive gas-generating structural component is prepared by the following method: pressing the temperature-sensitive gas-generating material into shape, and then encapsulating the pressed temperature-sensitive gas-generating material with a packaging film to obtain the temperature-sensitive gas-generating structural component.

[0026] For example, 0.1-10g of temperature-sensitive gas-generating material is pressed into a sheet shape using a tablet press, and then the pressed temperature-sensitive gas-generating material is encapsulated with a packaging film to prepare the temperature-sensitive gas-generating structural component.

[0027] According to an embodiment of the present invention, the battery casing can be a hard casing; the hard casing is, for example, a plastic casing or an aluminum casing.

[0028] The beneficial effects of this utility model are:

[0029] This invention proposes a battery thermal management device, which includes a temperature-sensitive gas-generating structure. Under normal operating conditions of a single battery cell, this structure is solid and does not contact the electrolyte within the cell, thus having no impact on the electrochemical performance of the cell or battery pack. However, when a single battery cell is in a faulty state, or when the temperature inside the battery casing or aluminum-plastic film rises to a set threshold, the structure changes from solid to gas. This rapidly increases the pressure inside the battery casing or aluminum-plastic film. When the pressure exceeds the set threshold, the high pressure forces open the pressure relief valve, rupture the safety valve, or break through the aluminum-plastic film, forming a pressure relief channel. This allows the high-temperature material inside the battery casing or aluminum-plastic film to escape, thereby reducing the internal temperature and achieving the purpose of battery thermal management. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the battery thermal management device described in Embodiment 1 of this utility model.

[0031] Figure 2 This is a schematic diagram of the battery thermal management device described in Embodiment 2 of this utility model.

[0032] Figure 3 This is a schematic diagram of the battery thermal management device described in Embodiment 3 of this utility model.

[0033] Figure 4 This is a schematic diagram illustrating the working principle of the battery thermal management device described in Embodiment 1 of this utility model.

[0034] Figure 5 This is a schematic diagram illustrating the working principle of the battery thermal management device described in Embodiment 1 of this utility model.

[0035] Figure 6 This is a schematic diagram illustrating the working principle of the battery thermal management device described in Embodiment 1 of this utility model.

[0036] The attached diagram shows the following symbols: 1 for battery casing, 2 for battery cell 2, 3 for temperature-sensitive gas-generating structure, 4 for positive electrode post, 5 for negative electrode post, 6 for pressure relief valve or safety valve, 7 for positive electrode tab, 8 for negative electrode tab, 11 for aluminum-plastic film, 41 for positive electrode foil, 51 for negative electrode foil, 111 for top sealing edge, 112 for side sealing edge, 113 for folded edge, and 114 for double sealing edge. Detailed Implementation

[0037] The technical solution of this utility model will be further described in detail below with reference to specific embodiments. It should be understood that the following embodiments are only illustrative and explanatory of this utility model, and should not be construed as limiting the scope of protection of this utility model. All technologies implemented based on the above content of this utility model are covered within the scope of protection intended by this utility model.

[0038] Unless otherwise specified, the experimental methods used in the following examples are conventional methods; unless otherwise specified, the reagents and materials used in the following examples are commercially available.

[0039] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings.

[0040] Obviously, the described embodiments are only some, not all, of the embodiments in this application. All other embodiments obtained by those skilled in the art based on the embodiments in this application without inventive effort are within the scope of protection of this application.

[0041] Example 1

[0042] Figure 1 This is a schematic diagram of the battery thermal management device provided in Example 1. Figure 1 As shown, the battery thermal management device includes: a battery casing 1, a battery cell 2, and a temperature-sensitive gas-generating structure 3; the battery casing 1 is provided with a positive electrode post 4, a negative electrode post 5, and a pressure relief valve or safety valve 6; the battery cell includes a positive electrode plate, a negative electrode plate, a positive electrode tab 7, a negative electrode tab 8, and a separator;

[0043] The battery cell 2 is disposed inside the battery casing 1; the battery casing 1 is filled with electrolyte, which wets the battery cell 2; the positive electrode is connected to the positive electrode post 4 through the positive electrode tab 7, and the negative electrode is connected to the negative electrode post 5 through the negative electrode tab 8.

[0044] The temperature-sensitive gas-generating structure 3 is positioned between the positive electrode tab 7 and the negative electrode tab 8.

[0045] When the temperature inside the battery casing 1 exceeds the set threshold, the temperature-sensitive gas-generating structure 3 generates a large amount of gas. The gas increases the pressure inside the battery casing 1. When the pressure inside the battery casing 1 exceeds the set pressure of the pressure relief valve or safety valve 6, the pressure relief valve is opened or the safety valve is ruptured, and the high-temperature material (such as electrolyte) inside the battery casing 1 is carried out of the battery casing 1, thereby rapidly reducing the temperature inside the battery casing 1.

[0046] Specifically, Figure 4 This is a schematic diagram illustrating the working principle of the battery thermal management device described in Embodiment 1 of this utility model. Figure 4 The image in the middle left represents a solid temperature-sensitive gas-generating material. Figure 4 The image on the right represents a gaseous, temperature-sensitive gas-generating material. (Reference) Figure 4 The temperature-sensitive gas-generating structure 3 is solid and small in size at normal temperatures. When the temperature rises to a given threshold (e.g., 100-140°C), it... o After C), the temperature-sensitive gas-generating structure 3 changes from a solid state to a gaseous state, and its volume increases rapidly.

[0047] Figure 5 This is a schematic diagram illustrating the working principle of the battery thermal management device described in Embodiment 1 of this utility model. Figure 5 The middle left figure represents the following: At room temperature, the temperature-sensitive gas-generating material inside the temperature-sensitive gas-generating structure is solid, has a small volume, and low pressure inside the shell. Figure 5 The middle right diagram illustrates that when the temperature exceeds a given threshold, the temperature-sensitive gas-generating material within the temperature-sensitive gas-generating structure releases a large amount of gas, resulting in high pressure inside the casing. Referring to Figure 5, the temperature-sensitive gas-generating material within the temperature-sensitive gas-generating structure 3 is solid and small in volume at normal temperatures, and therefore does not exert any pressure on the battery casing 1. When the temperature rises to a given threshold (e.g., 100-140°C), the pressure increases. o After C), the temperature-sensitive gas-generating material in the temperature-sensitive gas-generating structure 3 changes from solid to gaseous, and its volume increases rapidly. Under the constraint of the battery casing 1 (the volume of the battery casing 1 cannot increase), the pressure inside the battery casing 1 increases rapidly.

[0048] Figure 6 This is a schematic diagram illustrating the working principle of the battery thermal management device described in Embodiment 1 of this utility model. Figure 6 The middle left diagram represents the following: At room temperature, the temperature-sensitive gas-generating material inside the temperature-sensitive gas-generating structure is solid, has a small volume, and low pressure inside the shell; at this time, under low pressure, the pressure relief valve is closed. Figure 6 The diagram on the right illustrates that when the temperature exceeds a given threshold, the temperature-sensitive gas-generating material releases a large amount of gas, resulting in high pressure inside the casing. Under this high-pressure condition, the pressure relief valve opens, and high-temperature electrolyte is ejected, carrying away the heat. (Reference) Figure 6The temperature-sensitive gas-generating structure 3 is solid and small in size at normal temperatures, so it does not exert any pressure on the battery casing 1, and the pressure relief valve or safety valve 6 is in the closed state. When a single cell is in a faulty state and the temperature inside the battery casing 1 rises to a given threshold (e.g., 100-140°C), the pressure relief valve or safety valve 6 will remain closed. o After C), the temperature-sensitive gas-generating material in the temperature-sensitive gas-generating structure 3 changes from a solid to a gaseous state, and its volume increases rapidly. Under the constraint of the battery casing 1 (the volume of the battery casing 1 cannot increase), the pressure inside the battery casing 1 increases rapidly. The pressure relief valve is opened or the safety valve is ruptured, forming a pressure relief channel. This allows the high-temperature material (such as electrolyte) inside the battery casing 1 to be discharged, rapidly reducing the temperature inside the battery casing 1 and thus preventing the single battery from burning due to excessive temperature. (100-140) o Within the temperature range of C, the separator has not yet melted over a large area. That is, before the separator melts over a large area, the temperature-sensitive gas-generating material will generate a large amount of gas. This gas will open the pressure relief valve, form a pressure relief channel, release high-temperature hot steam and carry away the heat, preventing the battery from reaching the flash point of the electrolyte solvent. Before the individual battery cells experience thermal runaway combustion, the heat inside the individual battery cells will be discharged. By releasing the heat inside the individual battery cells in advance, the battery pack is prevented from burning, thus achieving the purpose of battery thermal management.

[0049] Example 2

[0050] Figure 2 This is a schematic diagram of the battery thermal management device provided in Example 2. Figure 2 As shown, the battery thermal management device includes: a battery casing 1, a battery cell 2, and a temperature-sensitive gas-generating structure 3; the battery casing 1 is provided with a positive electrode post 4, a negative electrode post 5, and a pressure relief valve or safety valve 6; the battery cell includes a positive electrode plate, a negative electrode plate, a positive electrode tab 7, a negative electrode tab 8, and a separator;

[0051] The battery cell 2 is disposed inside the battery casing 1; the battery casing 1 is filled with electrolyte, which wets the battery cell 2; the positive electrode is connected to the positive electrode post 4 through the positive electrode tab 7, and the negative electrode is connected to the negative electrode post 5 through the negative electrode tab 8.

[0052] The temperature-sensitive gas-generating structure 3 is located on the inner bottom of the battery casing 1.

[0053] The working principle of the battery thermal management device provided in Example 2 is the same as that in Example 1. The temperature-sensitive gas-generating structure 3, which is set at the bottom inner side of the battery casing 1, operates when a single cell is in a fault state and the temperature inside the battery casing 1 rises to a given threshold (e.g., 100-140°C). oAfter C), the temperature-sensitive gas-generating material in the temperature-sensitive gas-generating structure 3 changes from solid to gas, and its volume increases rapidly. The pressure relief valve is opened or the safety valve is broken, forming a pressure relief channel. The high-temperature material (such as electrolyte) inside the battery case 1 is discharged from the battery case 1, and the temperature inside the battery case 1 is rapidly reduced, thereby preventing the single battery from burning due to excessive temperature and achieving the purpose of battery thermal management.

[0054] Example 3

[0055] The battery thermal management device provided in this embodiment includes: an aluminum-plastic film 11, a battery cell 2, and a temperature-sensitive gas-generating structure 3; a positive electrode foil 41 and a negative electrode foil 51 are disposed on the aluminum-plastic film 11; the battery cell includes a positive electrode sheet, a negative electrode sheet, a positive electrode tab 7, a negative electrode tab 8, and a separator;

[0056] The battery cell 2 is disposed inside the aluminum-plastic film 11; the aluminum-plastic film 11 is filled with electrolyte, which wets the battery cell 2; the positive electrode is connected to the positive electrode foil 41 through the positive electrode tab 7, and the negative electrode is connected to the negative electrode foil 51 through the negative electrode tab 8; the aluminum-plastic film 11 includes a top sealing edge 111, a side sealing edge 112, a folded edge 113, and a second sealing edge 114; the side sealing edge 112 and the top sealing edge 111 are adjacent to the folded edge 113, and the side sealing edge 112 and the second sealing edge 114 are opposite to each other;

[0057] The temperature-sensitive gas-generating structure 3 is located between the aluminum-plastic film 11 and the battery cell 2, near the second sealing edge 114 of the aluminum-plastic film 11.

[0058] The working principle of the battery thermal management device provided in Example 3 is the same as that in Example 1. The temperature-sensitive gas-generating structure 3, located near the second sealing edge 114 of the aluminum-plastic film 11 between the aluminum-plastic film 11 and the battery cell 2, operates when the single battery cell is in a fault state and the temperature inside the aluminum-plastic film rises to a given threshold (e.g., 100-140°C). o After C), the temperature-sensitive gas-generating material in the temperature-sensitive gas-generating structure 3 changes from solid to gas, and its volume increases rapidly. The aluminum-plastic film is broken, forming a pressure relief channel, which discharges the high-temperature material (such as electrolyte) inside the aluminum-plastic film 11. The temperature inside the aluminum-plastic film 11 is rapidly reduced, thereby preventing the single battery from burning due to excessive temperature and achieving the purpose of battery thermal management.

[0059] The embodiments of this utility model have been described above. However, this utility model is not limited to the above embodiments. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A battery thermal management device, characterized in that, The battery thermal management device includes: a battery casing, a battery cell, and a temperature-sensitive gas-generating structure; the battery casing is provided with a positive electrode post, a negative electrode post, a pressure relief valve or a safety valve; the battery cell includes a positive electrode plate, a negative electrode plate, a positive electrode tab, a negative electrode tab, and a separator; The battery cell is disposed inside the battery casing; the battery casing is filled with electrolyte, which wets the battery cell; the positive electrode is connected to the positive terminal through a positive electrode tab, and the negative electrode is connected to the negative terminal through a negative electrode tab; The temperature-sensitive gas-generating structure is located between the positive electrode tab and the negative electrode tab; or, the temperature-sensitive gas-generating structure is located at the bottom inner side of the battery casing.

2. The battery thermal management device according to claim 1, characterized in that, The pressure relief valve or safety valve is located between the positive and negative terminals.

3. A battery thermal management device, characterized in that, The battery thermal management device includes: an aluminum-plastic film, a battery cell, and a temperature-sensitive gas-generating structure; a positive electrode foil and a negative electrode foil are disposed on the aluminum-plastic film; the battery cell includes a positive electrode sheet, a negative electrode sheet, a positive electrode tab, a negative electrode tab, and a separator; The battery cell is disposed inside the aluminum-plastic film; the aluminum-plastic film is filled with electrolyte, which wets the battery cell; the positive electrode is connected to the positive electrode foil through a positive electrode tab, and the negative electrode is connected to the negative electrode foil through a negative electrode tab; the aluminum-plastic film includes a top sealing edge, a side sealing edge, a folded edge, and a second sealing edge; the side sealing edge and the top sealing edge are adjacent to the folded edge, and the side sealing edge and the second sealing edge are opposite to each other; The temperature-sensitive gas-generating structure is located between the aluminum-plastic film and the battery cell, near the second sealing edge of the aluminum-plastic film.

4. The battery thermal management device according to claim 1 or 3, characterized in that, The diaphragm is disposed between the positive electrode and the negative electrode.

5. The battery thermal management device according to claim 1 or 3, characterized in that, The temperature-sensitive gas-generating structure includes a temperature-sensitive gas-generating material and a packaging film, wherein the packaging film is disposed on the outer surface of the temperature-sensitive gas-generating material.

6. The battery thermal management device according to claim 5, characterized in that, The thickness of the packaging film is 10-100 μm.

7. The battery thermal management device according to claim 1 or 3, characterized in that, The shape of the temperature-sensitive gas-generating structure is rectangular, square, circular, or elliptical.

8. The battery thermal management device according to claim 1 or 3, characterized in that, The thickness of the temperature-sensitive gas-generating structure is 0.05-50mm.

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