Battery and manufacturing method thereof, battery module, battery pack and electric equipment

Abstract

The invention provides a battery and a manufacturing method thereof, a battery module, a battery pack and electric equipment. The battery comprises a shell, a cover plate assembly, a first insulating part and a second insulating part, the cover plate assembly is fixedly arranged at the first end of the shell; the first insulating part and the second insulating part at least jointly and completely cover the side face of the shell, the first insulating part extends from the second end of the shell to a preset position, the preset position is located between the connecting position and the second end of the shell, and the second insulating part extends from the first end of the cover plate assembly to cover the connecting position and is at least partially overlapped with the first insulating part; the distance between the first insulating part and the joint is D1, the extension length of the second insulating part in the first direction is D2, the heat conductivity coefficient of the second insulating part is lambda, and D1, D2 and lambda meet the following relation: 0.016 < = (D2-D1) / (D2 * lambda) < = 9.71. According to the battery, the heat dissipation performance of the battery can be effectively guaranteed, the insulation performance of the surface of the battery shell can effectively meet the insulation requirement, and the safety performance of the battery is effectively improved.

Description

Technical Field

[0001] The present application relates to the field of batteries, and specifically to a battery and a manufacturing method thereof, a battery module, a battery pack and an electrical device. Background Art

[0002] Battery casings are typically made of metal. To optimize battery product safety, insulating coverings are often applied to the outer surface of the casing to improve its insulation performance. These coverings primarily include insulating coatings and insulating films.

[0003] Since the battery shell and the cover assembly are welded together, there is a weld at the connection. Spraying the insulating coating at the weld is prone to insulation failure. When the insulating film is affixed, the insulating film at the weld is damaged and warped, etc., which easily causes the risk of insulation failure. Therefore, two insulating covers can be stacked at the weld of the battery shell to avoid insulation failure at the weld.

[0004] However, when the overlapping area of ​​the two insulating covers is too large, it is difficult for the heat inside the battery to dissipate outward from the two insulating covers, which can easily lead to poor heat dissipation of the battery or even thermal runaway problems, resulting in a decrease in the safety performance of the battery. Summary of the Invention

[0005] In view of this, the embodiments of the present application are dedicated to providing a battery and a manufacturing method thereof, a battery module, a battery pack and an electrical device to solve the problems of poor insulation and heat dissipation performance of existing batteries.

[0006] A first aspect of the present application provides a battery, comprising:

[0007] case;

[0008] a cover plate assembly, the cover plate assembly being fixedly disposed on a first end of the housing, and a connection being provided between the housing and the cover plate assembly on at least one side surface of the battery;

[0009] a first insulating member and a second insulating member, wherein the first insulating member and the second insulating member at least completely cover together a side surface of the housing where the connection is provided, and on the side surface of the housing where the connection is provided, the first insulating member extends from the second end of the housing to a predetermined position, the predetermined position being located between the connection and the second end of the housing, the second end being the other end opposite to the first end in the first direction, the second insulating member extending from the first end of the cover plate assembly to cover the connection and at least partially overlapping with the first insulating member;

[0010] The distance between the first insulating member and the connection is D1, measured in mm; the extension length of the second insulating member in the first direction is D2, measured in mm; the thermal conductivity of the second insulating member is λ, measured in W / (m·K); and D1, D2, and λ satisfy the following relationship: 0.016≤(D2-D1) / (D2*λ)≤9.71.

[0011] Another aspect of the present application provides a battery module including at least one battery.

[0012] Another aspect of the present application provides a battery pack including at least one battery.

[0013] Another aspect of the present application provides an electrical device including a battery.

[0014] Another aspect of the present application provides a method for manufacturing a battery, comprising:

[0015] A cover plate assembly is fixedly disposed on a first end of the housing, wherein a connection is formed between the housing and the cover plate assembly on at least one side of the battery;

[0016] The first insulating member and the second insulating member are covered on the shell and the cover assembly, wherein the first insulating member and the second insulating member at least completely cover the side of the shell where the connection is provided, and extend from the second end of the shell to a preset position in the first direction of the shell, and the preset position is located between the connection and the second end of the shell, the second end is the other end opposite to the first end in the first direction, the second insulating member extends from the first end of the cover assembly to cover the connection, and at least partially overlaps with the first insulating member; the distance between the first insulating member and the connection is D1, in mm, the extension length of the second insulating member in the first direction is D2, in mm, the thermal conductivity of the second insulating member is λ, in W / (m·K), and the following relationship is satisfied among D1, D2 and λ: 0.016≤(D2-D1) / (D2*λ)≤9.71.

[0017] In the battery of the present application, the distance between the first insulating part and the connection is D1, measured in mm, the extension length of the second insulating part in the first direction is D2, measured in mm, the thermal conductivity of the second insulating part is λ, measured in W / (m·K), and the following relationship is satisfied between D1, D2 and λ: 0.016≤(D2-D1) / (D2*λ)≤9.71. This can effectively ensure the heat dissipation performance of the battery, effectively reduce the probability of heat accumulation, thermal runaway, etc. during long-term operation of the battery, and ensure that the insulation performance of the battery shell surface can effectively meet the insulation requirements, and breakdown and leakage will not occur, thereby effectively improving the safety performance of the battery of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 shows a schematic diagram of the overall structure of a battery;

[0019] Figure 2 shows a schematic cross-sectional view of a battery;

[0020] Figure 3 shows another cross-sectional schematic diagram of a battery;

[0021] Figure 4 shows a schematic cross-sectional structure diagram of the battery of the present application;

[0022] Figure 5 shows a schematic cross-sectional structure diagram of another battery of the present application;

[0023] Figure 6 A schematic diagram showing the steps of the method for manufacturing the battery of the present application is shown.

[0024] Figure ID:

[0025] 10. Shell; 20. Cover assembly; 21. Pole; 22. Explosion-proof valve; 31. Winding core; 32. Pole ear; 41. First insulating member; 42. Second insulating member; 43. Connection. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0027] Should be noted that: unless otherwise specifically stated, otherwise the relative arrangement, numerical expression and numerical value of the parts and steps set forth in these embodiments do not limit the scope of the application. In all examples shown and discussed here, any specific value should be interpreted as merely exemplary, rather than as a restriction. Therefore, other examples of exemplary embodiments can have different values.

[0028] The following description sets forth numerous specific details to facilitate a thorough understanding of this application. However, this application can be implemented in many other ways than those described herein, and those skilled in the art may make similar generalizations without violating the scope of this application. Therefore, this application is not limited to the specific implementations disclosed below. Techniques, methods, and apparatus known to persons of ordinary skill in the relevant art may not be discussed in detail, but, where appropriate, should be considered part of the specification.

[0029] The terms used in one or more embodiments of the present application are for the purpose of describing specific embodiments only and are not intended to limit one or more embodiments of the present application. The singular forms "a", "an", "the" and "the" used in one or more embodiments of the present application and the appended claims are also intended to include plural forms, unless the context clearly indicates otherwise. It should also be understood that the term "and / or" used in one or more embodiments of the present application refers to and includes any or all possible combinations of one or more associated listed items.

[0030] It should be understood that although the terms first, second, etc. may be used to describe various information in one or more embodiments of the present application, such information should not be limited to these terms. These terms are only used to distinguish information of the same type from each other. For example, without departing from the scope of one or more embodiments of the present application, the first may also be referred to as the second, and similarly, the second may also be referred to as the first. Depending on the context, the word "if" as used herein may be interpreted as "at the time of" or "when" or "in response to a determination". In this article, "upper", "lower", "front", "back", "left", "right", etc. are only used to indicate the relative positional relationship between the relevant parts, rather than to limit the absolute position of these relevant parts. In this article, "equal", "same", etc. are not strict mathematical and / or geometric limitations, but also include errors that can be understood by those skilled in the art and are allowed by manufacturing or use. Unless otherwise specified, the numerical ranges herein include not only the entire range within its two endpoints, but also several sub-ranges contained therein.

[0031] like Figures 1 to 5 As shown, an embodiment of the present application provides a battery, which includes at least a housing 10 and a cover assembly 20, wherein the cover assembly 20 is fixedly disposed at a first end of the housing 10. The first direction of the housing 10 refers to the direction from the first end of the housing 10 where the cover assembly 20 is disposed to the other end. In this first direction, the two ends of the battery and each structure of the embodiment of the present application are respectively a first end and a second end, wherein the first end of the battery and each structure are all located on the same side as the cover assembly 20, and the second end is all located on the opposite side.

[0032] The shell 10 is mainly used to accommodate the main functional components of the battery, such as the winding core 31, and provides structural support and heat dissipation for the entire battery; the cover assembly 20 is mainly used to seal the battery together with the shell 10, and the cover assembly 20 is provided with positive and negative poles 21, which are used to achieve electrical conduction between the battery and the outside world. It can be understood that, if Figure 1As shown, the battery of the present application can be a square-shell battery, or a cylindrical battery or other battery with a hard shell 10, which will not be described in detail here. The battery of the present application can also include structures such as an explosion-proof valve 22 and a protection device. The explosion-proof valve 22 is used to release pressure or cut off current when the internal pressure of the battery is abnormal. The protection device is used to fuse when the battery is overcharged or in an abnormal situation, cutting off the current circuit and inhibiting further discharge of the battery.

[0033] like Figure 4 and Figure 5 As shown, a connection 43 is provided between the housing 10 and the cover assembly 20 on at least one side of the battery.

[0034] It can be understood that the square-shell battery has four sides, among which a connection 43 is provided between the shell 10 and the cover assembly 20 on at least one side; for the cylindrical battery, it has only one side, on which a connection 43 is provided between the shell 10 and the cover assembly 20. For batteries of other shapes, it is only necessary to ensure that a connection 43 is provided between the shell 10 and the cover assembly 20 on at least one side of the battery.

[0035] like Figure 4 and Figure 5 As shown, the battery of the present application further includes a first insulating member 41 and a second insulating member 42, which together at least completely cover the side surfaces of the housing 10. Since the first insulating member 41 and the second insulating member 42 together at least completely cover the side surfaces of the housing 10, it is ensured that any position on the side surfaces of the housing 10 is covered by the first insulating member 41 or the second insulating member 42, thereby preventing a portion of the housing 10 from being directly exposed, and effectively ensuring the insulation performance of the side surfaces of the battery housing 10 of the present application.

[0036] Therefore, if Figure 4 and Figure 5 As shown, in the battery of the present application, on the side of the shell 10 where the connection 43 is provided, the first insulating member 41 extends from the second end of the shell 10 to a preset position, and the preset position is located between the connection 43 and the second end of the shell 10, and the second end is the other end opposite to the first end in the first direction. The second insulating member 42 extends from the first end of the cover assembly 20 to cover the connection 43 and at least partially overlaps with the first insulating member 41.

[0037] That is, on the side of the housing 10 where the connection 43 is provided, the coverage area of ​​the first insulating member 41 extends from the second end of the housing 10 to a predetermined position between the connection 43 and the second end of the housing 10. There is a gap between the edge of the first insulating member 41 and the connection 43, and the first insulating member 41 does not cover the connection 43. The coverage area of ​​the second insulating member 42 extends from the first end of the cover assembly 20 to cover the connection 43 between the housing 10 and the cover assembly 20. The second insulating member 42 not only completely covers the side of the cover assembly 20 but also completely covers the connection 43 between the housing 10 and the cover assembly 20. It also extends downward from the connection 43 for a certain distance until it at least partially overlaps with the first insulating member 41. Because the first insulating member 41 and the second insulating member 42 at least partially overlap, a small area of ​​the housing 10 directly exposed between the first insulating member 41 and the second insulating member 42 can be avoided, thereby effectively improving the insulation performance of the edge portion between the first insulating member 41 and the second insulating member 42, preventing leakage and other problems.

[0038] It can be understood that in the first direction of the shell 10, when the distance between the edge of the first insulating member 41 and the connection 43 is large, the extension length of the second insulating member 42 in the first direction needs to be increased to ensure that there is sufficient overlapping area between the first insulating member 41 and the second insulating member 42 to ensure the insulation performance of the battery of the present application.

[0039] However, when the area of ​​the overlapping region between the first insulating member 41 and the second insulating member 42 increases, it is difficult for the heat inside the battery to dissipate outward from the overlapping region between the first insulating member 41 and the second insulating member 42, which can easily lead to poor heat dissipation of the battery or even thermal runaway problems, resulting in a decrease in the safety performance of the battery.

[0040] Therefore, this application selects a batch of sample batteries with the same specifications and sizes, and assembles the first insulating member 41 and the second insulating member 42 on the shell 10 according to the following embodiment Table 1; wherein, during the assembly process, the edge of the first insulating member 41 and the connection 43 have the same or different spacings, and the second insulating member 42 is assembled on the cover assembly 20, and the thickness and other properties of the second insulating member 42 are the same, and the extension size or thermal conductivity coefficient of the second insulating member 42 in the first direction of the shell 10 is different, see embodiment Table 1 for details; and the assembled batteries are subjected to thermal conductivity performance test and insulation test.

[0041] Thermal conductivity test method: Select insulating film materials of different materials and the same thickness, cut them into two flat samples of 50×50mm respectively, place the samples in a constant temperature and humidity chamber at a temperature of 23±2℃ and a relative humidity of 50%, and let them stand for 24 hours to eliminate the influence of temperature and humidity.

[0042] The equipment used is a transient hot wire instrument. The hot wire sensor is clamped between two samples of the same material, ensuring that the contact surface is flat. A pressure of 0.1MPa is applied, the transient hot wire instrument is started, the heating power is set to 1W, and the temperature rise curve within 60 seconds is recorded. The thermal conductivity coefficient is automatically calculated by software fitting. The same position is measured 3 times, and the average value is recorded as the thermal conductivity coefficient of the sample of the corresponding material.

[0043] Among them, the test method for thermal conductivity is to place the sample battery in a heating box for heating at a temperature of 105°C for 10 minutes. After the heating is completed, the battery is placed in a 25°C environment and allowed to cool for 30 minutes, and then the temperature of the battery pole 21 is measured. It is understandable that during the operation of the battery, the battery cells inside the battery will generate heat, and the heat generation at the pole 21 position is the most serious. Usually, the heat inside the battery needs to be dissipated to the outside through the battery shell. At this time, the outer surface of the shell is covered with insulating parts, and the thermal conductivity of different insulating parts is also different. If the temperature test is performed directly on the outer surface of the shell, there will be measurement errors. The pole assembly is electrically connected to the battery body through the pole ear. Therefore, by measuring the temperature of the battery pole 21, the heat inside the battery can be better reflected, and the influence of the first insulating part 41 and the second insulating part 42 on the heat dissipation performance of the shell 10 can be reflected.

[0044] The insulation test method involves selecting two identical sample batteries from each group and placing them side by side at a testing station with a 1mm spacing. The positive and negative terminals of the insulation withstand voltage tester are connected to the exposed leakage areas of the two sample battery covers. The withstand voltage meter is set to 4000V DC for 60 seconds. The maximum leakage current during the test is measured in mA. A leakage current greater than 0.5mA is considered unqualified.

[0045] In the following embodiment, in the battery of the present application, the distance between the first insulating member 41 and the connection 43 is D1, measured in mm, the extension length of the second insulating member 42 in the first direction is D2, measured in mm, and the thermal conductivity coefficient of the second insulating member 42 is λ, measured in W / (m·K), wherein the thermal conductivity coefficient λ of the second insulating member 42 is only related to the material of the second insulating member 42 and is not related to other parameters of the second insulating member 42.

[0046]

[0047]

[0048]

[0049]

[0050] Table 1

[0051] In the battery of the present application, the distance between the first insulating member 41 and the connection 43 is D1, measured in mm, the extension length of the second insulating member 42 in the first direction is D2, measured in mm, and the thermal conductivity of the second insulating member 42 is λ, measured in W / (m·K).

[0052] According to actual test results, in Examples 1-24, the relationship between D1, D2, and λ satisfies the following: 0.016 ≤ (D2 - D1) / (D2 * λ) ≤ 9.71. The temperature of the battery terminal 21 is relatively low, reaching a qualified level within the designed time. In the insulation test, no breakdown or leakage occurs, indicating excellent insulation performance, meeting design requirements, and no other defects. In Examples 25-38, the heat dissipation and insulation performance of the sample batteries also meet design requirements.

[0053] In comparative examples 1-6, the value of (D2-D1) / (D2*λ) is greater than 9.71, and the battery insulation performance test meets the design requirements. However, the heat dissipation at the battery pole 21 is slow, which affects the safety performance of the battery during operation and has the risk of causing thermal runaway.

[0054] According to analysis, the value of (D2-D1) / (D2*λ) is greater than 9.71, which is mainly due to the fact that the thermal conductivity λ of the second insulating member 42 is too small and the value of (D2-D1) / D2 is too large; if the thermal conductivity λ of the second insulating member 42 is too small, it will easily lead to slow heat dissipation of the battery in the embodiment of the present application, and the value of (D2-D1) / D2 is too large, that is, the area of ​​the overlapping region between the first insulating member 41 and the second insulating member 42 is too large relative to the area of ​​the second insulating member 42 itself, and the area of ​​the overlapping region between the first insulating member 41 and the second insulating member 42 is usually larger, and heat is difficult to dissipate from the overlapping region between the first insulating member 41 and the second insulating member 42, resulting in poor heat dissipation performance of the battery.

[0055] In Comparative Examples 7-10, the value of (D2-D1) / (D2*λ) is less than 0.016, and the heat dissipation performance of the battery meets the relevant requirements. However, the insulation performance test of the battery does not meet the design requirements. According to analysis, the value of (D2-D1) / (D2*λ) is less than 0.016. Since the thermal conductivity λ of the second insulating member 42 cannot be too small, this is mainly caused by the value of (D2-D1) / D2 being too small. The value of (D2-D1) / D2 is too small, that is, the overlapping area between the first insulating member 41 and the second insulating member 42 is too small relative to the area of ​​the second insulating member 42 itself. The overlapping area between the first insulating member 41 and the second insulating member 42 is generally small. If the upper part of the first insulating member 41 or the second insulating member 42 is damaged or warped, it is easy to cause the insulation performance of the battery to fail. Therefore, according to the above data, in the battery of the present application, the distance between the first insulating part 41 and the connection 43 is D1, the unit is mm, the extension length of the second insulating part 42 in the first direction is D2, the unit is mm, the thermal conductivity coefficient of the second insulating part 42 is λ, the unit is W / (m·K), and the following relationship is satisfied between D1, D2 and λ: 0.016≤(D2-D1) / (D2*λ)≤9.71. The heat dissipation performance of the battery can be effectively guaranteed, and the probability of heat accumulation, thermal runaway, etc. in the battery during long-term operation can be effectively reduced. It also ensures that the insulation performance of the surface of the battery shell 10 can effectively meet the insulation requirements, and breakdown and leakage will not occur, thereby effectively improving the safety performance of the battery of the present application.

[0056] In one embodiment of the present application, in the battery of the present application, the cover plate assembly 20 is welded to the first end of the shell 10, and a weld line is formed at the connection 43 between the shell 10 and the cover plate assembly 20. Specifically, the cover plate assembly 20 can be welded to the first end of the shell 10 using a laser welding process, so that the cover plate assembly 20 can form a sealed integral structure with the shell 10. In another embodiment of the present application, in the battery of the present application, the cover plate assembly 20 can also be welded to the first end of the shell 10 by bonding or other solid-state battery processes, which are not limited here.

[0057] like Figure 4As shown, in one embodiment of the present application, in the area where the first insulating member 41 and the second insulating member 42 overlap, the first insulating member 41 is arranged on the surface of the shell 10, and the second insulating member 42 is arranged on the first insulating member 41. In this way, during the assembly process of the battery of the present application, the first insulating member 41 can be assembled first, and then the second insulating member 42 can be assembled, so as to ensure that the first insulating member 41 is arranged on the surface of the shell 10 and the second insulating member 42 is arranged on the first insulating member 41. Since there is a gap between the first insulating member 41 and the connection 43, it is ensured that the first insulating member 41 and the connection 43 do not contact each other, which can ensure that the first insulating member 41 is assembled in the set position; then, when the second insulating member 42 partially overlaps with the first insulating member 41, it can be ensured that the second insulating member 42 completely covers the connection 43, thereby ensuring the insulation performance of the connection 43.

[0058] Specifically, when the first insulating part 41 is arranged on the surface of the shell 10 and the second insulating part 42 is partially arranged on the first insulating part 41, in one embodiment of the present application, the first insulating part 41 can be an insulating coating and the second insulating part 42 is an insulating film; that is, during the assembly process of the battery of the present application, the insulating coating can be sprayed on the corresponding position of the first insulating part 41 first, and then the insulating film can be covered on the corresponding position of the second insulating part 42 on the side of the cover assembly 20 and the shell 10. This can effectively avoid the problem of incomplete coverage of the insulating coating at the edge of the insulating film due to the uneven surface when the insulating film is covered first and then the insulating coating is sprayed, thereby further ensuring the insulation performance of the battery of the present application.

[0059] It can be understood that the insulating coating is a structure obtained by covering the shell 10 with insulating paint by spraying, brushing, etc.; the insulating film is a film-like structure with insulating properties.

[0060] Of course, in another embodiment of the present application, the first insulating member 41 and the second insulating member 42 may both be insulating coatings; in this way, during the assembly process of the battery of the present application, the insulating coating may be sprayed on the corresponding position of the first insulating member 41 first, and then the insulating coating may be sprayed on the corresponding position of the second insulating member 42 on the side of the cover assembly 20 and the shell 10. It can be understood that the material, thickness and other parameters of the insulating coating corresponding to the first insulating member 41 and the second insulating member 42 may be the same or different, and are not limited here.

[0061] like Figure 5As shown, in one embodiment of the present application, in the area where the first insulating member 41 and the second insulating member 42 overlap, the second insulating member 42 is disposed on the surface of the housing 10, and the first insulating member 41 is disposed on the second insulating member 42. During the assembly process of the battery of the present application, the second insulating member 42 can be assembled first, and then the first insulating member 41 can be assembled, to ensure that the second insulating member 42 is disposed on the surface of the housing 10, and the first insulating member 41 is disposed on the second insulating member 42. That is, when assembling the second insulating member 42, the second insulating member 42 is completely covered by the connection 43, and then the second insulating member 42 is partially overlapped with the first insulating member 41, so that the second insulating member 42 completely covers the connection 43, thereby ensuring the insulation performance of the connection 43.

[0062] It can be understood that in one embodiment of the present application, the second insulating member 42 can be attached to the surface of the shell 10, and the first insulating member 41 can be attached to the second insulating member 42. In another embodiment of the present application, the first insulating member 41, the second insulating member 42 and the shell 10 can also be separated by other structures.

[0063] It is understood that in one embodiment of the present application, in the area where the first insulating member 41 and the second insulating member 42 overlap, the second insulating member 42 is disposed on the surface of the housing 10, and when the first insulating member 41 is disposed on the second insulating member 42, the first insulating member 41 is an insulating film and the second insulating member 42 is an insulating film. In this way, it can be effectively ensured that the connection 43 is covered by two layers of insulating film to ensure the insulation performance of the battery of the present application. It is understood that in one embodiment of the present application, the second insulating member 42 can be attached to the surface of the housing 10, and the first insulating member 41 can be attached to the second insulating member 42. In another embodiment of the present application, the first insulating member 41, the second insulating member 42 and the housing 10 can also be separated by other structures.

[0064] In one embodiment of the present application, a connection 43 is provided between the shell 10 and the cover assembly 20 on all sides of the battery, and on all sides of the battery, the distance between the first insulating member 41 and the connection 43 is D1, in mm, the extension length of the second insulating member 42 in the first direction is D2, in mm, the thermal conductivity coefficient of the second insulating member 42 is λ, in W / (m·K), and the following relationship is satisfied between D1, D2 and λ: 0.016≤D2-D1 / D2*λ≤9.71.

[0065] That is, on all sides of the battery, a connection 43 is provided between the shell 10 and the cover assembly 20, and on all sides of the battery, the following relationship is satisfied between D1, D2 and λ: 0.016≤D2-D1 / D2*λ≤9.71, which can effectively ensure the heat dissipation performance of all sides of the battery, effectively reduce the probability of heat accumulation, thermal runaway, etc. during long-term operation of the battery, and ensure that the insulation performance of the surface of the battery shell 10 can effectively meet the insulation requirements, and breakdown and leakage will not occur, thereby effectively improving the safety performance of the battery of this application.

[0066] In one embodiment of the present application, in the first direction of the shell 10, the first insulating member 41 extends at all circumferential lengths around the side surface of the shell 10, which can ensure that the performance of the first insulating member 41 at all circumferential locations on the side surface of the shell 10 is relatively consistent; similarly, in one embodiment of the present application, in the first direction of the shell 10, the second insulating member 42 extends at all circumferential lengths around the side surface of the shell 10, which can ensure that the performance of the second insulating member 42 at all circumferential locations on the side surface of the shell 10 is relatively consistent.

[0067] It can be understood that, in the first direction of the shell 10, when the first insulating member 41 extends at all circumferential lengths around the side of the shell 10 and the second insulating member 42 extends at all circumferential lengths around the side of the shell 10, it can be effectively ensured that the insulation performance of each position on the side of the battery of the present application remains consistent, and there will be no situation where the insulation performance of some areas is poor.

[0068] In the case where the first insulating part 41 is an insulating coating or the second insulating part 42 is an insulating coating, when the circumferential extension lengths of the first insulating part 41 and / or the second insulating part 42 around the side of the shell 10 are equal, it is convenient to complete the spraying of the insulating coating by rotating the coating nozzle or rotating the shell 10, which can effectively improve the spraying efficiency of the insulating coating.

[0069] In the case where the first insulating member 41 is an insulating film or the second insulating member 42 is an insulating film, when the first insulating member 41 and / or the second insulating member 42 extend at equal lengths around the circumference of the side of the shell 10, it can not only effectively reduce the difficulty of cutting and covering the insulating film, but also when the battery expands during use, the expansion amplitude of the battery shell 10 in all directions remains equal, and there will be no situation where the battery shell 10 expands less in some directions and expands more in some directions. This avoids cracking at the connection 43 between the shell 10 and the cover assembly 20 due to greater expansion in some positions, causing dangerous situations such as electrolyte leakage and external protection. It can also avoid uneven distribution of expansion force, which leads to an increase in the local temperature rise rate and heat accumulation.

[0070] In one embodiment of the present application, the first insulating member 41 is an insulating coating, the second insulating member 42 is an insulating film, 1≤D1≤less than 30, and the unit is mm.

[0071] In Examples 27, 28, 29, and 30 of Table 1, D1 is less than 1 mm. Thus, when spraying the corresponding insulating coating of the first insulating member 41, due to the small distance between the first insulating member 41 and the connection 43, part of the coating of the first insulating member 41 is easily splashed onto the cover assembly 20 and the connection 43, which will affect the adhesion of the second insulating member 42 when attaching the second insulating member 42, and easily cause the adhesion of some areas of the second insulating member 42 to be not firm enough; moreover, the first insulating member 41 on the cover assembly 20 will also affect the electrical connection when the batteries are later grouped and assembled into a box.

[0072] In Examples 31, 32, 33, and 34 of Table 1, D1 is greater than 30 mm. Since the distance between the first insulating member 41 and the connection 43 is large, the insulating film of the second insulating member 42 needs to cover more of the area between the first insulating member 41 and the connection 43, resulting in the lower edge of the second insulating member 42 being closer to the middle position of the battery shell 10; it is understandable that during the long-term use of the battery, since the expansion of the battery is not uniform, the expansion amplitude of the middle position in the first direction is usually larger. Since the lower edge of the second insulating member 42 is closer to the middle position of the battery shell 10, after the middle of the battery is over-expanded, it is easy to cause the second insulating member 42 and the first insulating member 41 to separate at the connection 43, and there is a risk of leakage.

[0073] In Table 1, D1 in Examples 1, 4, 7, 10, 25, 26, 35, and 36 is 1 mm; D1 in Examples 3, 9, 11, 2, 8, 23, 6, 17, 15, 16, 18, 22, 5, 14, and 20 satisfies 1<D1<less than 30, and the unit is mm; D1 in Examples 12, 13, 19, 21, 24, 37, and 38 is 30 mm.

[0074] Therefore, when the first insulating part 41 is an insulating coating and the second insulating part 42 is an insulating film, and 1≤D1≤is less than 30, expressed in mm, it is possible to prevent the paint of the first insulating part 41 from splashing onto the cover assembly 20 and the connection 43, and prevent the splashed first insulating part 41 from affecting the bonding and subsequent electrical connection of the second insulating part 42; moreover, the lower end edge of the second insulating part 42 can be located in the upper half of the battery shell 10 close to the cover assembly 20, which can effectively ensure that during long-term use of the battery, it is not easy for the second insulating part 42 and the first insulating part 41 to separate at the connection 43 due to the expansion of the middle part of the battery, thereby preventing the risk of leakage.

[0075] In one embodiment of the present application, the second insulating member 42 is an insulating film, 3≤D2≤35, in mm. In Examples 25, 26, and 27 of Table 1, the extension length D2 of the second insulating member 42 in the first direction is less than 3 mm. This results in a small bonding area between the second insulating member 42 and the housing 10, and the bonding between the second insulating member 42 and the housing 10 is not strong enough. In addition, during long-term use of the battery, the upper half of the battery, where the pole 21 is usually located, generates more heat. If the extension length D2 of the second insulating member 42 in the first direction is small, the second insulating member 42 is prone to warping or even falling off completely, thereby greatly reducing the insulation performance of the battery housing 10 of the present application and reducing the safety performance of the battery of the present application.

[0076] In Examples 28, 33, 34, and 35 of Table 1, D2 is greater than 35 mm. Since the extension length D2 of the second insulating member 42 in the first direction is large, not only is the overall coverage area of ​​the second insulating member 42 large, which easily leads to assembly defects during the covering process of the second insulating member 42, but also the lower edge of the second insulating member 42 is relatively close to the middle position of the battery shell 10. After the middle area of ​​the battery expands excessively, it is easy to cause the second insulating member 42 and the first insulating member 41 to separate at the connection 43, posing a risk of leakage.

[0077] In Table 1, D2 in Examples 29, 1, 4, 36, and 3 is 3 mm; D2 in Examples 9, 11, 2, 17, 6, 15, 16, 18, 8, 23, 14, 22, 12, 13, 19, 5, 37, 31, and 32 satisfies 3<D2<35, and the unit is mm; D2 in Examples 30, 7, 10, 20, 21, 24, and 38 is 35 mm.

[0078] Therefore, when the second insulating part 42 is an insulating film, 3≤D2≤35, and the unit is mm, it can ensure that the second insulating part 42 and the shell 10 are firmly bonded, and even during long-term use of the battery, the second insulating part 42 is not likely to warp, effectively ensuring the insulation performance of the battery shell 10 of the present application and improving the safety performance of the battery of the present application; it can also effectively improve the heat dissipation performance of the second insulating part 42, so that the lower end edge of the second insulating part 42 can be located in the upper half of the battery shell 10 close to the cover assembly 20, which can effectively ensure that during long-term use of the battery, the second insulating part 42 and the first insulating part 41 are not likely to separate at the connection 43 due to the expansion of the middle part of the battery, thereby preventing the risk of leakage.

[0079] In one embodiment of the present application, λ ranges from 0.1 W / (m·K) to 1 W / (m·K).

[0080] In Examples 37, 32, 38, and 33 in Table 1, λ is less than or equal to 0.1 W / (m·K). Since the thermal conductivity of the second insulating member 42 is relatively small, the temperature of the pole 21 is generally high during long-term use of the battery, which can easily cause thermal runaway of the battery of the present application, thereby posing a safety risk.

[0081] In one embodiment of the present application, λ is less than 1 W / (m·K). In Examples 27, 28, 34, and 36 in Table 1, λ is greater than or equal to 1 W / (m·K). Due to the general properties of the material, the thermal conductivity of the second insulating member 42 is too high, and the insulation performance of the second insulating member 42 is also reduced.

[0082] In Table 1, λ in Examples 25, 1, 3, 6, 15, 12, 31, 7, and 21 is 0.1 W / (m·K); λ in Examples 9, 17, 18, 8, 2, 19, 20, and 23 satisfies 0.1<λ<1, with the unit being W / (m·K); and λ in Examples 26, 29, 4, 11, 16, 14, 22, 13, 5, 30, 10, 24, and 35 is 1 W / (m·K). Therefore, when λ is in the range of 0.1 W / (m·K) to 1 W / (m·K), not only can the thermal conductivity between the second insulating member 42 and the housing 10 be effectively ensured to be excellent, but even during long-term use of the battery, localized overheating is unlikely to occur, effectively ensuring the heat dissipation performance of the battery housing 10 of the present application and improving the safety performance of the battery of the present application; furthermore, the second insulating member 42 can be made of a material with relatively excellent insulating properties, thereby improving the insulation performance of the battery of the present application.

[0083] like Figure 2 and Figure 3 As shown, in one embodiment of the present application, the second insulating member 42 is an insulating film. In the battery of the present application, the shell 10 and the cover assembly 20 together form a accommodating cavity; the battery also includes at least one winding core 31 arranged in the accommodating cavity, and in the first direction of the shell 10, the second end of the second insulating member 42 is located between the first end and the second end of the winding core 31.

[0084] It is understandable that during long-term use of the battery, the side of the battery shell 10 is prone to expansion; since the second insulating member 42 can provide a certain restraining force during the battery expansion process, that is, a greater expansion force is required to drive the second insulating member 42 to expand, therefore, at the same position on the side of the battery shell 10, the part covered with the second insulating member 42 usually expands less than the part not covered with the second insulating member 42.

[0085] Since the second end of the second insulating member 42 is located between the first end and the second end of the core 31 in the first direction of the shell 10, during the expansion of the battery, the second insulating member 42 can be staggered with the first end of the core 31, and the second insulating member 42 can provide a certain restraining force to the partial area between the first end and the second end of the core 31. That is, during the expansion of the battery, the corresponding area between the first end and the second end of the core 31 that overlaps with the second insulating member 42 can withstand the restraining force of the second insulating member 42 as a whole, and only the first end of the core 31 will not withstand the restraining force of the second insulating member 42, resulting in rapid damage or even tearing of the first end of the core 31, thereby improving the safety performance of the battery of the present application to a certain extent.

[0086] It is understandable that if Figure 3 As shown, two winding cores 31 can be provided in the battery of the present application as needed, and in another embodiment of the present application, other numbers of winding cores 31 can also be provided, which is not limited here.

[0087] Furthermore, in one embodiment of the present application, in the first direction of the housing 10, the distance D3 between the second end of the second insulating member 42 and the first end of the winding core 31 ranges from 10 mm to 30 mm. Because the distance D3 between the second end of the second insulating member 42 and the first end of the winding core 31 in the first direction of the housing 10 ranges from 10 mm to 30 mm, the second insulating member 42 can maintain a certain distance from the first end of the winding core 31. During the battery expansion process, the corresponding area between the first and second ends of the winding core 31 that overlaps with the second insulating member 42 is larger, which can better withstand the restraining force of the second insulating member 42, preventing the first end of the winding core 31 from being rapidly damaged or even torn due to the restraint of the second insulating member 42, further improving the safety performance of the battery of the present application.

[0088] In another embodiment of the present application, in the battery of the present application, the second insulating member 42 is an insulating film, and the shell 10 and the cover assembly 20 together form a accommodating cavity; the battery also includes at least one winding core 31 arranged in the accommodating cavity, and in the first direction of the shell 10, the second end of the second insulating member 42 is located above the first end of the winding core 31.

[0089] Since in the first direction of the shell 10, the second end of the second insulating member 42 is located above the first end of the core 31, the second end of the second insulating member 42 can be located in the area corresponding to the pole ear 32; the second insulating member 42 can maintain a certain distance from the first end of the core 31, and in the first direction, the second insulating member 42 and the core 31 do not overlap with each other; during the expansion of the battery, the second insulating member 42 will not provide a restraining force to the corresponding area where the core 31 is located, and the corresponding area where the core 31 is located can expand outward evenly, and there will be no situation where a part of the core 31 is quickly damaged or even torn, which can also improve the safety performance of the battery of the present application.

[0090] like Figure 1 As shown, in one embodiment of the present application, the battery of the present application also includes a pole 21 and an explosion-proof valve 22, and the pole 21 and the explosion-proof valve 22 are both arranged on the top surface of the cover assembly 20; the second insulating member 42 also covers the area of ​​the top surface of the cover assembly 20 except the pole 21 and the explosion-proof valve 22; the first insulating member 41 also covers the bottom surface of the shell 10.

[0091] In this embodiment, since the pole 21 and the explosion-proof valve 22 are both arranged on the top surface of the cover assembly 20, the second insulating member 42 also covers the area of ​​the top surface of the cover assembly 20 except the pole 21 and the explosion-proof valve 22, and the first insulating member 41 also covers the bottom surface of the shell 10, which can ensure that the outer surface of the battery of the present application except the pole 21 and the explosion-proof valve 22 is covered by at least one of the second insulating member 42 and the first insulating member 41, thereby effectively ensuring the insulation performance of the outer surface of the battery of the present application.

[0092] In another embodiment of the present application, the battery of the present application further includes a pole 21 and an explosion-proof valve 22, the pole 21 is arranged on the top surface of the cover assembly 20; the explosion-proof valve 22 is arranged on the bottom surface of the shell 10; the second insulating member 42 also covers the area of ​​the top surface of the cover assembly 20 except the pole 21; the first insulating member 41 also covers the area of ​​the bottom surface of the shell 10 except the explosion-proof valve 22.

[0093] In this embodiment, since the pole 21 is arranged on the top surface of the cover assembly 20 and the explosion-proof valve 22 is arranged on the bottom surface of the shell 10, the second insulating member 42 also covers the area of ​​the top surface of the cover assembly 20 except the pole 21; the first insulating member 41 also covers the area of ​​the bottom surface of the shell 10 except the explosion-proof valve 22, and can also ensure that the outer surface of the battery of the present application except the pole 21 and the explosion-proof valve 22 is covered by at least one of the second insulating member 42 and the first insulating member 41, thereby effectively ensuring the insulation performance of the outer surface of the battery of the present application.

[0094] The present application also provides a battery module, which includes at least one of the aforementioned batteries. Specifically, the number of the aforementioned batteries included in the battery module is not limited.

[0095] The present application also provides a battery pack comprising at least one aforementioned battery. It is understood that, in one embodiment of the present application, the battery pack may comprise at least one aforementioned battery module, each of which may comprise at least one aforementioned battery. In another embodiment of the present application, the battery pack may consist solely of the aforementioned battery and other necessary components.

[0096] The present application also provides an electrical device comprising at least one of the aforementioned batteries. It is understood that the electrical device may be any of a variety of electrical devices, including electric vehicles, battery-powered appliances, and energy storage devices, without limitation. The electrical device may directly comprise the aforementioned battery, or may comprise a battery module or battery pack.

[0097] like Figure 6 As shown, the embodiment of the present application also provides a method for manufacturing a battery, comprising:

[0098] Step S101: fix the cover assembly 20 to the first end of the housing 10;

[0099] A connection 43 is formed between the housing 10 and the cover assembly 20 on at least one side surface of the battery.

[0100] Step S102: The first insulating member 41 and the second insulating member 42 are covered on the housing 10 and the cover assembly 20.

[0101] In which, the first insulating member 41 and the second insulating member 42 at least jointly completely cover the side of the shell 10 where the connection 43 is provided, and extend from the second end of the shell 10 to a preset position in the first direction of the shell 10, the preset position is located between the connection 43 and the second end of the shell 10, the second end is the other end opposite to the first end in the first direction, the second insulating member 42 extends from the first end of the cover assembly 20 to cover the connection 43, and at least partially overlaps with the first insulating member 41; the spacing between the first insulating member 41 and the connection 43 is D1, the unit is mm, the extension length of the second insulating member 42 in the first direction is D2, the unit is mm, the thermal conductivity coefficient of the second insulating member 42 is λ, the unit is W / (m·K), and the following relationship is satisfied between D1, D2 and λ: 0.016≤D2-D1 / D2*λ≤9.71.

[0102] In the battery obtained by the manufacturing method of the battery of the present application, the distance between the first insulating member 41 and the connection 43 is D1, the unit is mm, the extension length of the second insulating member 42 in the first direction is D2, the unit is mm, the thermal conductivity of the second insulating member 42 is λ, the unit is W / (m·K), and D1, D2 and λ satisfy the following relationship: 0.016≤(D2-D1) / (D2*λ)≤9.71. The heat dissipation performance of the obtained battery can be effectively guaranteed, and the probability of heat accumulation, thermal runaway, etc. in the battery during long-term operation can be effectively reduced. It also ensures that the insulation performance of the surface of the battery shell 10 can effectively meet the insulation requirements, and breakdown and leakage will not occur, thereby effectively improving the safety performance of the battery of the present application.

[0103] It is understandable that the above further limitations on the battery can be applied to the manufacturing method of the aforementioned battery. The effects can be referred to above and will not be repeated here.

[0104] The above are only preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements, etc. made within the spirit and principles of the present application should be included in the scope of protection of the present application.

[0105] Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is selected to best explain the principles of the embodiments, their practical applications, or technological improvements in the marketplace, or to enable others skilled in the art to understand the embodiments disclosed herein. The scope of this application is defined by the appended claims.

Claims

1. A battery, characterized in that: include: Housing (10); a cover plate assembly (20), the cover plate assembly (20) being fixedly disposed on a first end of the housing (10), and a connection (43) being provided between the housing (10) and the cover plate assembly (20) on at least one side surface of the battery; a first insulating member (41) and a second insulating member (42), wherein the first insulating member (41) and the second insulating member (42) at least completely cover together a side surface of the shell (10) where the connection (43) is provided, and on the side surface of the shell (10) where the connection (43) is provided, the first insulating member (41) extends from the second end of the shell (10) to a preset position, the preset position being located between the connection (43) and the second end of the shell (10), the second end being the other end opposite to the first end in the first direction, and the second insulating member (42) extends from the first end of the cover plate assembly (20) to cover the connection (43) and at least partially overlaps with the first insulating member (41); The distance between the first insulating member (41) and the connection (43) is D1, in mm; the extension length of the second insulating member (42) in the first direction is D2, in mm; the thermal conductivity of the second insulating member (42) is λ, in W / (m·K); and the relationship between D1, D2 and λ satisfies the following: 0.016≤(D2-D1) / (D2*λ)≤9.

71.

2. The battery according to claim 1, characterized in that In the area where the first insulating member (41) and the second insulating member (42) overlap, the first insulating member (41) is arranged on the surface of the housing (10), and the second insulating member (42) is arranged on the first insulating member (41).

3. The battery according to claim 1, characterized in that The first insulating member (41) is an insulating coating, and the second insulating member (42) is an insulating film or an insulating coating.

4. The battery according to claim 1, characterized in that In the area where the first insulating member (41) and the second insulating member (42) overlap, the second insulating member (42) is arranged on the surface of the housing (10), and the first insulating member (41) is arranged on the second insulating member (42).

5. The battery according to claim 1, characterized in that The first insulating member (41) is an insulating film, and the second insulating member (42) is an insulating film.

6. The battery according to claim 1, characterized in that On all sides of the battery, a connection point (43) is provided between the housing (10) and the cover plate assembly (20), and on all sides of the battery, a distance between the first insulating member (41) and the connection point (43) is D1, in mm, an extension length of the second insulating member (42) in the first direction is D2, in mm, a thermal conductivity coefficient of the second insulating member (42) is λ, in W / (m·K), and the following relationship is satisfied among D1, D2 and λ: 0.016≤(D2-D1) / (D2*λ)≤9.

71.

7. The battery according to claim 6, characterized in that In a first direction of the housing (10), the first insulating member (41) has an equal extension length at all locations around the circumference of the side surface of the housing (10); And / or, in the first direction of the shell (10), the second insulating member (42) has the same extension length at all locations around the circumference of the side surface of the shell (10).

8. The battery according to any one of claims 1 to 7, characterized in that The first insulating member (41) is an insulating coating, The second insulating member (42) is an insulating film, 1≤D1≤30, unit is mm.

9. The battery according to any one of claims 1 to 7, characterized in that The second insulating member (42) is an insulating film, 3≤D2≤35, unit is mm.

10. The battery according to any one of claims 1 to 7, characterized in that The range of λ is 0.1 W / (m·K) to 1 W / (m·K).

11. The battery according to any one of claims 1 to 7, characterized in that The cover plate assembly (20) is welded to the first end of the shell (10), and a welding line is formed at the connection (43) between the shell (10) and the cover plate assembly (20).

12. The battery according to any one of claims 1 to 7, characterized in that The second insulating member (42) is an insulating film, and the housing (10) and the cover assembly (20) together form a receiving cavity; The battery further comprises at least one winding core (31) disposed in the accommodating cavity, and in the first direction of the housing (10), the second end of the second insulating member (42) is located between the first end and the second end of the winding core (31).

13. The battery according to claim 12, characterized in that In the first direction of the housing (10), a distance D3 between the second end of the second insulating member (42) and the first end of the winding core (31) ranges from 10 mm to 30 mm.

14. The battery according to any one of claims 1 to 7, characterized in that The housing (10) and the cover assembly (20) together form a receiving cavity; The battery further comprises at least one winding core (31) disposed in the accommodating cavity, and in the first direction of the housing (10), the second end of the second insulating member (42) is located above the first end of the winding core (31).

15. The battery according to any one of claims 1 to 7, characterized in that It also includes a pole (21) and an explosion-proof valve (22), wherein the pole (21) and the explosion-proof valve (22) are both arranged on the top surface of the cover plate assembly (20); The second insulating member (42) also covers the top surface of the cover plate assembly (20) except the pole (21) and the explosion-proof valve (22); and the first insulating member (41) also covers the bottom surface of the housing (10).

16. The battery according to any one of claims 1 to 7, characterized in that It also includes a pole (21) and an explosion-proof valve (22), wherein the pole (21) is arranged on the top surface of the cover plate assembly (20); and the explosion-proof valve (22) is arranged on the bottom surface of the housing (10); The second insulating member (42) also covers the top surface of the cover plate assembly (20) except the pole (21); the first insulating member (41) also covers the bottom surface of the housing (10) except the explosion-proof valve (22).

17. A battery module, characterized in that: Comprising at least one battery according to any one of claims 1 to 16.

18. A battery pack, characterized in that: Comprising at least one battery according to any one of claims 1 to 16.

19. An electrical device, characterized in that: Comprising at least one battery according to any one of claims 1 to 16.

20. A method for manufacturing a battery, characterized in that: include: A cover plate assembly (20) is fixedly disposed on a first end of a housing (10), wherein a connection (43) is formed between the housing (10) and the cover plate assembly (20) on at least one side surface of the battery; The first insulating member (41) and the second insulating member (42) are covered on the shell (10) and the cover plate assembly (20), wherein the first insulating member (41) and the second insulating member (42) at least completely cover the side of the shell (10) where the connection (43) is provided, and extend from the second end of the shell (10) to a preset position in the first direction of the shell (10), and the preset position is located between the connection (43) and the second end of the shell (10), and the second end is the other end opposite to the first end in the first direction, and the second end is the other end opposite to the first end in the first direction. The insulating member (42) extends from the first end of the cover plate assembly (20) to cover the connection (43) and at least partially overlaps with the first insulating member (41); the distance between the first insulating member (41) and the connection (43) is D1, in mm; the extension length of the second insulating member (42) in the first direction is D2, in mm; the thermal conductivity of the second insulating member (42) is λ, in W / (m·K); D1, D2 and λ satisfy the following relationship: 0.016≤(D2-D1) / (D2*λ)≤9.71.

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