Structural member, preparation method thereof and battery

Abstract

The invention belongs to the technical field of batteries, and particularly relates to a structural member and a preparation method thereof.The structural member is of a porous structure, a fireproof flame retardant is contained in the structural member, and the structural member is provided with a sealing structure used for isolating the fireproof flame retardant from the outside; wherein the sealing structure is configured to be damaged at a preset temperature, so that the fireproof flame retardant is in contact with an external substance; the structural member is provided with at least one mounting groove, and the mounting groove is used for accommodating the corner area of the winding type battery cell. Through the supporting effect of the structural member on the corner area of the battery cell, the deformation of the pole piece in the corner area caused by stress can be inhibited, and the performance of the battery cell is improved; the fireproof flame retardant is sealed in the porous structural member, the electrolyte is isolated from the fireproof flame retardant in normal, and low viscosity and good conductivity of the electrolyte are kept; and when the temperature of the battery cell rises to a preset temperature, the sealing structure is damaged by heat, and the fireproof flame retardant in the sealing structure is quickly released to block a chain reaction, so that thermal runaway caused by continuous temperature rise is avoided.

Description

Technical Field

[0001] The present invention belongs to the technical field of batteries, and in particular relates to a structural component, a preparation method thereof, and a battery. Background Art

[0002] Secondary batteries are widely used in consumer electronics, energy storage and power batteries due to their high specific energy, long cycle life and low self-discharge. With the widespread application of secondary batteries, the requirements for battery charging rate, cycle performance and storage performance are becoming higher and higher. Currently, the electrolytes of secondary batteries are mostly organic liquid electrolytes, and their solvents have very low flash points and are extremely flammable. Under abuse, the batteries are very likely to cause thermal runaway and lead to safety problems. The current flame retardant scheme for secondary batteries usually directly introduces fire retardants into the electrolyte. Although the flame retardant effect is achieved, it also increases the viscosity of the electrolyte and reduces the conductivity of the electrolyte, thereby reducing the electrical performance and cycle performance of the battery cell. Moreover, there is a certain amount of residual space left after assembly at the corner area of ​​the winding process battery cell. The corner area is also a stress concentration area during the charging and discharging process, and is most prone to interface failures such as wrinkles, lithium or sodium precipitation. Summary of the invention

[0003] The purpose of the present invention is to provide a structural component and a preparation method thereof in view of the deficiencies in the prior art, wherein a fire retardant is sealed in the pores of the structural component, and when the battery cell is operating normally, the electrolyte is isolated from the flame retardant, thereby maintaining the low viscosity and good conductivity of the electrolyte. When the battery cell is abused and the temperature rises sharply, the fire retardant is triggered to be released to improve the safety of the battery cell under abuse, thereby enabling the battery to have both excellent electrical performance and safety performance.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions:

[0005] A structural component, the structural component has a porous structure, the structural component contains a fire retardant, and the structural component is provided with a sealing structure for isolating the fire retardant from the outside world; wherein the sealing structure is configured to be damaged at a preset temperature so that the fire retardant comes into contact with external substances; the structural component is provided with at least one mounting groove, and the mounting groove is used to accommodate a corner area of ​​a wound battery cell.

[0006] Preferably, the melting point of the material of the structural member is higher than the preset temperature.

[0007] Preferably, the material of the structural member is insulating material; and / or, the material of the structural member is ceramic or plastic; and / or, the preset temperature is 80-140°C.

[0008] Preferably, the porosity of the structural member is 15±5%, and the pore diameter is 800-1000 μm.

[0009] Preferably, the porosity of the structural member is 30±5%, and the pore diameter is 600-800 μm.

[0010] Preferably, the porosity of the structural member is 45±5%, and the pore diameter is 400-600 μm.

[0011] Preferably, the fire retardant is one or more phosphorus-based flame retardants such as triphenyl phosphate (TPP), trifluoroethyl phosphite (TTFP), ammonium polyphosphate (APP), ammonium phosphate salt, etc.; and / or, the sealing structure is a sealing film, the sealing structure is coated on the outer surface of the structural member to seal the fire retardant in the structural member, and the material of the sealing film is PE.

[0012] A method for preparing a structural part comprises the following steps:

[0013] Step 1, dissolving the fire retardant in a volatile solvent;

[0014] Step 2, immersing the structural component into the above solvent;

[0015] Step 3, heating and volatilizing the soaked structural parts;

[0016] Step 4: providing a sealing structure on the structural member.

[0017] A battery comprises: a shell; at least one battery cell accommodated in the shell; and at least one structural member mentioned above accommodated in the shell.

[0018] Preferably, the battery core is a wound structure, the battery core comprises a straight area and corner areas located at both ends of the straight area, the structural member is provided with at least one mounting groove, and the corner area is mounted in the mounting groove.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention provides a structural component and a preparation method thereof, which can suppress the deformation of the electrode in the corner area due to stress and improve the performance of the battery cell through the support of the structural component to the battery cell corner area, and the fire retardant is sealed in the porous structural component. When the battery cell is operating normally, that is, the battery cell has not yet experienced thermal runaway and the temperature of the battery cell has not yet reached the preset temperature, the external substances, that is, the electrolyte, are isolated from the fire retardant due to the sealing structure, thereby maintaining the low viscosity and good conductivity of the electrolyte; when the battery cell is abused, the temperature of the battery cell rises, and once the temperature of the battery cell reaches the preset temperature, the sealing structure will be damaged by heat. At this time, the fire retardant in the structural component can contact with the electrolyte, thereby quickly blocking the chain reaction and avoiding thermal runaway caused by the continuous rise in temperature. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1It is a schematic diagram of the battery assembly structure of the present invention.

[0021] Figure 2 It is a schematic diagram of the structure of the structural member of the present invention.

[0022] Reference numerals:

[0023] 1. Structural parts, 11. Sealing structure, 12. Mounting groove;

[0024] 2. Battery cell, 21. Straight area, 22. Corner area. DETAILED DESCRIPTION

[0025] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] Embodiment 1:

[0027] like Figure 1-2 As shown, a structural component 1 is provided in this embodiment. The structural component 1 has a porous structure, specifically, it is composed of a porous insulating material with good adsorption properties. The structural component 1 contains a fire retardant, the fire retardant is placed in the pores and is firmly adsorbed. When the battery cell 2 is operating normally, the electrolyte is isolated from the fire retardant, so that the low viscosity and good conductivity of the electrolyte are maintained. When the battery cell 2 is abused and the temperature rises sharply, the fire retardant is triggered to release to improve the safety of the battery cell 2 under abuse conditions, so that the battery has both excellent electrical performance and safety performance.

[0028] The structural member 1 is provided with a sealing structure 11 for isolating the fire retardant from the outside; wherein the sealing structure 11 is configured to break at a preset temperature so that the fire retardant comes into contact with external substances;

[0029] In the case of abuse of the battery cell 2, once the temperature of the battery cell 2 exceeds the preset temperature, the sealing structure 11 coated on the surface of the porous structural member 1 is damaged to release the fire retardant, which can quickly block the chain reaction and prevent the continuous rise of heat from causing thermal runaway.

[0030] The structural member 1 is provided with at least one mounting groove 12, and the mounting groove 12 is used to accommodate the corner area 22 of the wound battery cell 2. The battery cell 2 can be tightly protected and securely fixed in the housing, and the corner area of ​​the battery cell 2 can be supported, so that the deformation of the pole piece in the corner area caused by stress can be suppressed, and the performance of the battery cell 2 can be improved.

[0031] Furthermore, the melting point of the material of the structural member 1 is higher than the preset temperature. When the temperature inside the battery cell 2 rises and reaches the preset temperature, the sealing structure 11 is damaged, while the structural member 1 itself remains unchanged.

[0032] Furthermore, the material of the structural member 1 is an insulating material; the material of the structural member 1 is ceramic, and the preset temperature of the sealing structure 11 is 140°C.

[0033] Furthermore, the porosity of the structural member 1 is 15±5%, and the pore size is 800-1000μm. The porosity of the structural member 1 is low, but its pore size is relatively large. When the temperature of the battery cell 2 reaches 140°C, the sealing structure 11 on the surface of the fire retardant contained therein is quickly damaged, and the fire retardant can also immediately overflow from the large pores, quickly playing a blocking effect to prevent the continuous rise of heat from causing thermal runaway.

[0034] Furthermore, the fire retardant is TTFP; the sealing structure 11 is a sealing film, which is coated on the outer surface of the structural member 1 to seal the fire retardant in the structural member 1. The material of the sealing film is PE, and the melting temperature of the PE material used is 140°C.

[0035] A battery comprises a housing, at least one battery cell 2 accommodated in the housing, and at least one structural member 1 as described above accommodated in the housing. In this embodiment, two battery cells 2 stacked on each other are arranged in the battery housing.

[0036] Furthermore, the battery cell 2 is a winding structure, and the battery cell 2 includes a straight area 21 and corner areas 22 located at both ends of the straight area 21. The structural member 1 is provided with at least one mounting groove 12, and the corner area 22 is installed in the mounting groove 12. Specifically, a structural member 1 is provided at each of the corner areas 22 at both ends of the battery cell 2, and the structural member 1 is provided with a C-shaped mounting groove 12, and the opening of the mounting groove 12 faces the corner area 22 and fits closely therewith. The other surfaces of the structural member 1 are straight planes, which are distributed and fit with the inner wall of the shell, so as to support and stabilize the corner area of ​​the battery cell 2, suppress the deformation of the pole piece in the corner area due to stress, and improve the performance of the battery cell 2.

[0037] Embodiment 2:

[0038] like Figure 1-2As shown, a structural component 1 is provided in this embodiment. The structural component 1 has a porous structure, specifically, it is composed of a porous insulating material with good adsorption properties. The structural component 1 contains a fire retardant, the fire retardant is placed in the pores and is firmly adsorbed. When the battery cell 2 is operating normally, the electrolyte is isolated from the fire retardant, so that the low viscosity and good conductivity of the electrolyte are maintained. When the battery cell 2 is abused and the temperature rises sharply, the fire retardant is triggered to release to improve the safety of the battery cell 2 under abuse conditions, so that the battery has both excellent electrical performance and safety performance.

[0039] The structural member 1 is provided with a sealing structure 11 for isolating the fire retardant from the outside; wherein the sealing structure 11 is configured to break at a preset temperature so that the fire retardant comes into contact with external substances;

[0040] In the case of abuse of the battery cell 2, once the temperature of the battery cell 2 exceeds the preset temperature, the sealing structure 11 coated on the surface of the porous structural member 1 is damaged to release the fire retardant, which can quickly block the chain reaction and prevent the continuous rise of heat from causing thermal runaway.

[0041] The structural member 1 is provided with at least one mounting groove 12, and the mounting groove 12 is used to accommodate the corner area 22 of the wound battery cell 2. The battery cell 2 can be tightly protected and securely fixed in the housing, and the corner area of ​​the battery cell 2 can be supported, so that the deformation of the pole piece in the corner area caused by stress can be suppressed, and the performance of the battery cell 2 can be improved.

[0042] Furthermore, the melting point of the material of the structural member 1 is higher than the preset temperature. When the temperature inside the battery cell 2 rises and reaches the preset temperature, the sealing structure 11 is damaged, while the structural member 1 itself remains unchanged.

[0043] Furthermore, the material of the structural member 1 is insulating material; the material of the structural member 1 is ceramic, and the preset temperature of the sealing structure 11 is 130°C.

[0044] Furthermore, the porosity of the structural member 1 is 30±5%, and the pore size is 600-800μm. The porosity of the structural member 1 is moderate, and its pore size is moderate. When the temperature of the battery cell 2 reaches 130°C, the sealing structure 11 on the surface of the fire retardant contained therein is quickly damaged, and the fire retardant can also immediately overflow from the large pores, quickly playing a blocking effect to prevent the continuous rise of heat from causing thermal runaway.

[0045] Furthermore, the fire retardant is TTFP; the sealing structure 11 is a sealing film, which is coated on the outer surface of the structural member 1 to seal the fire retardant in the structural member 1. The material of the sealing film is PE, and the melting temperature of the PE material used is 130°C.

[0046] A battery comprises a housing, at least one battery cell 2 accommodated in the housing, and at least one structural member 1 as described above accommodated in the housing. In this embodiment, two battery cells 2 stacked on each other are arranged in the battery housing.

[0047] Furthermore, the battery cell 2 is a winding structure, and the battery cell 2 includes a straight area 21 and corner areas 22 located at both ends of the straight area 21. The structural member 1 is provided with at least one mounting groove 12, and the corner area 22 is installed in the mounting groove 12. Specifically, a structural member 1 is provided at each of the corner areas 22 at both ends of the battery cell 2, and the structural member 1 is provided with a C-shaped mounting groove 12, and the opening of the mounting groove 12 faces the corner area 22 and fits closely therewith. The other surfaces of the structural member 1 are straight planes, which are distributed and fit with the inner wall of the shell, so as to support and stabilize the corner area of ​​the battery cell 2, suppress the deformation of the pole piece in the corner area due to stress, and improve the performance of the battery cell 2.

[0048] Embodiment 3:

[0049] like Figure 1-2 As shown, a structural component 1 is provided in this embodiment. The structural component 1 has a porous structure, specifically, it is composed of a porous insulating material with good adsorption properties. The structural component 1 contains a fire retardant, the fire retardant is placed in the pores and is firmly adsorbed. When the battery cell 2 is operating normally, the electrolyte is isolated from the fire retardant, so that the low viscosity and good conductivity of the electrolyte are maintained. When the battery cell 2 is abused and the temperature rises sharply, the fire retardant is triggered to release to improve the safety of the battery cell 2 under abuse conditions, so that the battery has both excellent electrical performance and safety performance.

[0050] The structural member 1 is provided with a sealing structure 11 for isolating the fire retardant from the outside; wherein the sealing structure 11 is configured to break at a preset temperature so that the fire retardant comes into contact with external substances;

[0051] In the case of abuse of the battery cell 2, once the temperature of the battery cell 2 exceeds the preset temperature, the sealing structure 11 coated on the surface of the porous structural member 1 is damaged to release the fire retardant, which can quickly block the chain reaction and prevent the continuous rise of heat from causing thermal runaway.

[0052] The structural member 1 is provided with at least one mounting groove 12, and the mounting groove 12 is used to accommodate the corner area 22 of the wound battery cell 2. The battery cell 2 can be tightly protected and securely fixed in the housing, and the corner area of ​​the battery cell 2 can be supported, so that the deformation of the pole piece in the corner area caused by stress can be suppressed, and the performance of the battery cell 2 can be improved.

[0053] Furthermore, the melting point of the material of the structural member 1 is higher than the preset temperature. When the temperature inside the battery cell 2 rises and reaches the preset temperature, the sealing structure 11 is damaged, while the structural member 1 itself remains unchanged.

[0054] Furthermore, the material of the structural member 1 is an insulating material; the material of the structural member 1 is ceramic, and the preset temperature of the sealing structure 11 is 120°C.

[0055] Furthermore, the porosity of the structural member 1 is 45±5%, and the pore size is 400-600μm. The porosity of the structural member 1 is relatively high, but its pore size is relatively small. When the temperature of the battery cell 2 reaches 120°C, the sealing structure 11 on the surface of the fire retardant contained therein is quickly damaged, and the fire retardant can also immediately overflow from the large pores, quickly playing a blocking effect to prevent the continuous rise of heat from causing thermal runaway.

[0056] Furthermore, the fire retardant is TTFP; the sealing structure 11 is a sealing film, which is coated on the outer surface of the structural member 1 to seal the fire retardant in the structural member 1. The material of the sealing film is PE, and the melting temperature of the PE material used is 120°C.

[0057] A battery comprises a housing, at least one battery cell 2 accommodated in the housing, and at least one structural member 1 as described above accommodated in the housing. In this embodiment, two battery cells 2 stacked on each other are arranged in the battery housing.

[0058] Furthermore, the battery cell 2 is a winding structure, and the battery cell 2 includes a straight area 21 and corner areas 22 located at both ends of the straight area 21. The structural member 1 is provided with at least one mounting groove 12, and the corner area 22 is installed in the mounting groove 12. Specifically, a structural member 1 is provided at each of the corner areas 22 at both ends of the battery cell 2, and the structural member 1 is provided with a C-shaped mounting groove 12, and the opening of the mounting groove 12 faces the corner area 22 and fits closely therewith. The other surfaces of the structural member 1 are straight planes, which are distributed and fit with the inner wall of the shell, so as to support and stabilize the corner area of ​​the battery cell 2, suppress the deformation of the pole piece in the corner area due to stress, and improve the performance of the battery cell 2.

[0059] Embodiment 4:

[0060] like Figure 1-2 As shown, a structural component 1 is provided in this embodiment. The structural component 1 has a porous structure, specifically, it is composed of a porous insulating material with good adsorption properties. The structural component 1 contains a fire retardant, the fire retardant is placed in the pores and is firmly adsorbed. When the battery cell 2 is operating normally, the electrolyte is isolated from the fire retardant, so that the low viscosity and good conductivity of the electrolyte are maintained. When the battery cell 2 is abused and the temperature rises sharply, the fire retardant is triggered to release to improve the safety of the battery cell 2 under abuse conditions, so that the battery has both excellent electrical performance and safety performance.

[0061] The structural member 1 is provided with a sealing structure 11 for isolating the fire retardant from the outside; wherein the sealing structure 11 is configured to break at a preset temperature so that the fire retardant comes into contact with external substances;

[0062] In the case of abuse of the battery cell 2, once the temperature of the battery cell 2 exceeds the preset temperature, the sealing structure 11 coated on the surface of the porous structural member 1 is damaged to release the fire retardant, which can quickly block the chain reaction and prevent the continuous rise of heat from causing thermal runaway.

[0063] The structural member 1 is provided with at least one mounting groove 12, and the mounting groove 12 is used to accommodate the corner area 22 of the wound battery cell 2. The battery cell 2 can be tightly protected and securely fixed in the housing, and the corner area of ​​the battery cell 2 can be supported, so that the deformation of the pole piece in the corner area caused by stress can be suppressed, and the performance of the battery cell 2 can be improved.

[0064] Furthermore, the melting point of the material of the structural member 1 is higher than the preset temperature. When the temperature inside the battery cell 2 rises and reaches the preset temperature, the sealing structure 11 is damaged, while the structural member 1 itself remains unchanged.

[0065] Furthermore, the material of the structural member 1 is an insulating material; the material of the structural member 1 is PVC, which has a melting point of 150°C, and the preset temperature of the sealing structure 11 is 120°C.

[0066] Furthermore, the porosity of the structural member 1 is 45±5%, and the pore size is 400-600μm. The porosity of the structural member 1 is relatively high, but its pore size is relatively small. When the temperature of the battery cell 2 reaches 120°C, the sealing structure 11 on the surface of the fire retardant contained therein is quickly damaged, and the fire retardant can also immediately overflow from the large pores, quickly playing a blocking effect to prevent the continuous rise of heat from causing thermal runaway.

[0067] Furthermore, the fire retardant is TTFP; the sealing structure 11 is a sealing film, which is coated on the outer surface of the structural member 1 to seal the fire retardant in the structural member 1. The material of the sealing film is PE, and the melting temperature of the PE material used is 120°C.

[0068] A battery comprises a housing, at least one battery cell 2 accommodated in the housing, and at least one structural member 1 as described above accommodated in the housing. In this embodiment, two battery cells 2 stacked on each other are arranged in the battery housing.

[0069] Furthermore, the battery cell 2 is a winding structure, and the battery cell 2 includes a straight area 21 and corner areas 22 located at both ends of the straight area 21. The structural member 1 is provided with at least one mounting groove 12, and the corner area 22 is installed in the mounting groove 12. Specifically, a structural member 1 is provided at each of the corner areas 22 at both ends of the battery cell 2, and the structural member 1 is provided with a C-shaped mounting groove 12, and the opening of the mounting groove 12 faces the corner area 22 and fits closely therewith. The other surfaces of the structural member 1 are straight planes, which are distributed and fit with the inner wall of the shell, so as to support and stabilize the corner area of ​​the battery cell 2, suppress the deformation of the pole piece in the corner area due to stress, and improve the performance of the battery cell 2.

[0070] Embodiment 5:

[0071] like Figure 1-2 As shown, a structural component 1 is provided in this embodiment. The structural component 1 has a porous structure, specifically, it is composed of a porous insulating material with good adsorption properties. The structural component 1 contains a fire retardant, the fire retardant is placed in the pores and is firmly adsorbed. When the battery cell 2 is operating normally, the electrolyte is isolated from the fire retardant, so that the low viscosity and good conductivity of the electrolyte are maintained. When the battery cell 2 is abused and the temperature rises sharply, the fire retardant is triggered to release to improve the safety of the battery cell 2 under abuse conditions, so that the battery has both excellent electrical performance and safety performance.

[0072] The structural member 1 is provided with a sealing structure 11 for isolating the fire retardant from the outside; wherein the sealing structure 11 is configured to break at a preset temperature so that the fire retardant comes into contact with external substances;

[0073] In the case of abuse of the battery cell 2, once the temperature of the battery cell 2 exceeds the preset temperature, the sealing structure 11 coated on the surface of the porous structural member 1 is damaged to release the fire retardant, which can quickly block the chain reaction and prevent the continuous rise of heat from causing thermal runaway.

[0074] The structural member 1 is provided with at least one mounting groove 12, and the mounting groove 12 is used to accommodate the corner area 22 of the wound battery cell 2. The battery cell 2 can be tightly protected and securely fixed in the housing, and the corner area of ​​the battery cell 2 can be supported, so that the deformation of the pole piece in the corner area caused by stress can be suppressed, and the performance of the battery cell 2 can be improved.

[0075] Furthermore, the melting point of the material of the structural member 1 is higher than the preset temperature. When the temperature inside the battery cell 2 rises and reaches the preset temperature, the sealing structure 11 is damaged, while the structural member 1 itself remains unchanged.

[0076] Furthermore, the material of the structural member 1 is an insulating material; the material of the structural member 1 is POM, which has a melting point of 170°C, and the preset temperature of the sealing structure 11 is 120°C.

[0077] Furthermore, the porosity of the structural member 1 is 45±5%, and the pore size is 400-600μm. The porosity of the structural member 1 is relatively high, but its pore size is relatively small. When the temperature of the battery cell 2 reaches 120°C, the sealing structure 11 on the surface of the fire retardant contained therein is quickly damaged, and the fire retardant can also immediately overflow from the large pores, quickly playing a blocking effect to prevent the continuous rise of heat from causing thermal runaway.

[0078] Furthermore, the fire retardant is TTFP; the sealing structure 11 is a sealing film, which is coated on the outer surface of the structural member 1 to seal the fire retardant in the structural member 1. The material of the sealing film is PE, and the melting temperature of the PE material used is 120°C.

[0079] A battery comprises a housing, at least one battery cell 2 accommodated in the housing, and at least one structural member 1 as described above accommodated in the housing. In this embodiment, two battery cells 2 stacked on each other are arranged in the battery housing.

[0080] Furthermore, the battery cell 2 is a winding structure, and the battery cell 2 includes a straight area 21 and corner areas 22 located at both ends of the straight area 21. The structural member 1 is provided with at least one mounting groove 12, and the corner area 22 is installed in the mounting groove 12. Specifically, a structural member 1 is provided at each of the corner areas 22 at both ends of the battery cell 2, and the structural member 1 is provided with a C-shaped mounting groove 12, and the opening of the mounting groove 12 faces the corner area 22 and fits closely therewith. The other surfaces of the structural member 1 are straight planes, which are distributed and fit with the inner wall of the shell, so as to support and stabilize the corner area of ​​the battery cell 2, suppress the deformation of the pole piece in the corner area due to stress, and improve the performance of the battery cell 2.

[0081] When preparing the structural member 1 in each of the above embodiments, the following method can be used: dissolve the fire retardant in a volatile solvent and then immerse it in the porous structural member 1, then evaporate the solvent to leave the fire retardant in the pores, and then coat the surface of the porous structural member 1 with a layer of PE film to prevent the electrolyte from entering the pores of the structural member 1 and dissolving the fire retardant. The porous structural member 1 is installed and filled in the residual space position in the corner area during the assembly of the battery cell. When the battery is working normally, the porous structural member 1 plays a supporting role to suppress the deformation of the electrode in the corner area caused by stress and improve the performance of the battery cell; when the battery cell is abused, the temperature of the battery cell rises sharply. When the temperature of the battery cell reaches 85-140°C, the PE film on the surface of the porous structural member 1 is gradually damaged by heat, and the electrolyte dissolves the fire retardant and blocks the potential thermal runaway risk.

[0082] According to the disclosure and teaching of the above description, those skilled in the art to which the present invention belongs can also change and modify the above embodiment. Therefore, the present invention is not limited to the above specific embodiment, and any obvious improvement, replacement or modification made by those skilled in the art on the basis of the present invention belongs to the protection scope of the present invention. In addition, although some specific terms are used in this specification, these terms are only for the convenience of description and do not constitute any limitation to the present invention.

Claims

1. A structural member, characterized in that: The structural member (1) has a porous structure, a fire retardant is contained in the structural member (1), and the structural member (1) is provided with a sealing structure (11) for isolating the fire retardant from the outside; wherein the sealing structure (11) is configured to break at a preset temperature so that the fire retardant comes into contact with external substances; the structural member (1) is provided with at least one mounting groove (12), and the mounting groove (12) is used to accommodate a corner area (22) of a wound battery cell.

2. The structural member according to claim 1, characterized in that: The melting point of the material of the structural component (1) is higher than the preset temperature.

3. The structural member according to claim 1, characterized in that: The material of the structural member (1) is an insulating material; and / or, The material of the structural member (1) is ceramic or plastic; and / or, The preset temperature is 80-140°C.

4. The structural member according to any one of claims 1 to 3, characterized in that: The porosity of the structural component (1) is 15±5%, and the pore diameter is 800-1000 μm.

5. The structural member according to any one of claims 1 to 3, characterized in that: The porosity of the structural component (1) is 30±5%, and the pore diameter is 600-800 μm.

6. The structural member according to any one of claims 1 to 3, characterized in that: The porosity of the structural member (1) is 45±5%, and the pore diameter is 400-600 μm.

7. The structural member according to any one of claims 1 to 3, characterized in that: The fire retardant is one or more of phosphorus-based flame retardants such as triphenyl phosphate (TPP), trifluoroethyl phosphite (TTFP), ammonium polyphosphate (APP), and ammonium phosphate salt; and / or, The sealing structure (11) is a sealing film, and the sealing structure (11) is coated on the outer surface of the structural component (1) to seal the fire retardant in the structural component (1). The material of the sealing film is PE.

8. A method for preparing a structural member according to any one of claims 1 to 7, characterized in that: The following steps are included: Step 1, dissolving the fire retardant in a volatile solvent; Step 2, immersing the structural component (1) into the above solvent; Step 3, heating and volatilizing the soaked structural component (1); Step 4: providing a sealing structure (11) on the structural member (1).

9. A battery, characterized in that: include: case; At least one battery cell (2) accommodated in the housing; At least one structural member according to any one of claims 1 to 7 is accommodated in the housing.

10. The battery according to claim 9, characterized in that: The battery core (2) is a wound structure, comprising a straight area (21) and corner areas (22) located at both ends of the straight area (21), the structural member (1) is provided with at least one mounting groove (12), and the corner area (22) is mounted in the mounting groove (12).

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