Battery, battery pack and electric device

Abstract

The invention discloses a battery, a battery pack and a power utilization device, the battery has a first direction and a second direction which are intersected, the battery comprises a shell, an electrode assembly and a top cover assembly, the shell is provided with a containing cavity, the electrode assembly is arranged in the containing cavity, the top cover assembly comprises a top cover piece and a lower insulating part, the top cover piece is connected with the shell and covers the containing cavity, and the lower insulating part is arranged in the containing cavity. The lower insulating part is connected to one side, facing the electrode assembly, of the top cover plate; the lower insulating part comprises a body and a first bulge, and the body is provided with at least two first through holes which are arranged at intervals along a first direction; the first protrusions are connected to the side, away from the top cover piece, of the body and arranged between every two adjacent first through holes. In the second direction, the size of the first protrusion is d, the distance between the body and the electrode assembly is n, and d / n is larger than or equal to 0.3 and smaller than 1; the sealing performance of the battery can be ensured, the deformation of the lower insulating part is effectively inhibited, and the safety performance of the battery is effectively improved.

Description

Technical Field

[0001] The present application belongs to the field of battery technology, and specifically relates to a battery, a battery pack and an electrical device. Background Art

[0002] Existing batteries require an insulating member to be spaced between the electrode assembly and the top cover to prevent short circuits inside the battery. However, since the insulating member is usually made of plastic, the longer the plastic is, the lower the strength in the middle is, and the middle part is more likely to deform downward, further squeezing the adapter sheet adjacent to the insulating member, causing the adapter sheet to deform or the connection between the adapter sheet and the electrode terminal to break, which in turn causes electrical connection failure and affects battery safety performance. Summary of the invention

[0003] Purpose of the invention: An embodiment of the present application provides a battery, aiming to solve the problem that the existing lower insulating member may deform, resulting in breakage of the connection between the adapter and the electrode terminal, thereby causing failure of the electrical connection and affecting the safety performance of the battery; another purpose of the embodiment of the present application is to provide a battery pack; another purpose of the embodiment of the present application is to provide an electrical device.

[0004] Technical solution: A battery according to an embodiment of the present application has a first direction and a second direction intersecting each other, including: A housing having a receiving cavity; An electrode assembly, disposed in the accommodating cavity; A top cover assembly comprises a top cover sheet and a lower insulating member, wherein the top cover sheet is connected to the shell and covers the accommodating cavity, and the lower insulating member is connected to the side of the top cover sheet facing the electrode assembly; the lower insulating member comprises a main body and a first protrusion, and the main body has at least two first through holes spaced apart along the first direction; the first protrusion is connected to the side of the main body away from the top cover sheet and is arranged between two adjacent first through holes; along the second direction, the size of the first protrusion is d mm, and the maximum distance between the main body and the electrode assembly is n mm, satisfying: 0.3≤d / n<1.

[0005] In some embodiments, The size d of the first protrusion satisfies: 1.5≤d<4; and / or, A maximum distance n between the body and the electrode assembly satisfies: 2≤n≤5.

[0006] In some embodiments, along the second direction, the size of the top cover sheet is a mm, the size of the accommodating cavity is b mm, the size of the electrode assembly is c mm, and the size of the body is m mm, satisfying: n=bacm, 0.3≤d / (bacm)<1.

[0007] In some embodiments, The size a of the top cover sheet satisfies: 1.5≤a≤2.5; and / or, The size b of the accommodating cavity satisfies: 60≤b≤300; and / or, The dimension c of the electrode assembly satisfies: 53.7≤c≤291; and / or, The size m of the body satisfies: 0.3≤m≤2.

[0008] In some embodiments, 0.015≤n / c≤0.084 is satisfied.

[0009] In some embodiments, the first protrusion has a first cavity, the body has a fourth through hole, and the first cavity is connected to the fourth through hole.

[0010] In some embodiments, the first protrusion includes a first side wall facing the electrode assembly, the first side wall has at least one second through hole, and the second through hole is connected to the first cavity.

[0011] In some embodiments, the first protrusion includes a second side wall oppositely arranged along the first direction, the second side wall intersects with the first side wall, the second side wall is provided with at least one third through hole, and the third through hole is connected to the first cavity.

[0012] In some embodiments, the area of ​​the second side wall is S1mm 2 The area of ​​the third through hole on the second side wall is S2mm 2 , satisfying: 0.3≤S2 / S1≤0.7.

[0013] In some embodiments, The area S1 of the second side wall satisfies: 20≤S1≤800; and / or, An area S2 of the third through hole on the second side wall satisfies: 6≤S2≤560.

[0014] In some embodiments, there is a third direction intersecting the first direction and the second direction respectively, the lower insulating member includes a plurality of the first protrusions, and at least two of the first protrusions are spaced apart along the third direction.

[0015] In some embodiments, along the third direction, the first cavities of two adjacent first protrusions penetrate the opposing side walls of the two first protrusions.

[0016] In some embodiments, the lower insulating member also includes at least two second protrusions spaced apart along the first direction, and the second protrusions are connected to the side of the body facing the electrode assembly; along the first direction, the first protrusions are spaced apart between two adjacent second protrusions, and at least one first through hole is provided between the first protrusion and the second protrusion.

[0017] In some embodiments, along the second direction, the size of the second protrusion is e mm, satisfying: d<e, e=n, and 0.015≤e / c≤0.084.

[0018] In some embodiments, the second protrusion has a second cavity and a third cavity spaced apart along the third direction, the body has a fifth through hole and a sixth through hole, the second cavity is connected to the fifth through hole, the third cavity is connected to the sixth through hole, and the third cavity passes through the side of the second protrusion away from the first protrusion along the first direction.

[0019] In some embodiments, along the second direction, the second cavity and the third cavity penetrate the side wall of the second protrusion toward the electrode assembly. In some embodiments, a pressure relief member is provided on the housing, and the pressure relief member is spaced apart from the electrode assembly along the second direction.

[0020] Accordingly, a battery pack described in an embodiment of the present application includes a battery described in any one of the aforementioned embodiments.

[0021] Correspondingly, the electrical device described in the embodiment of the present application includes the battery described in any one of the aforementioned embodiments, or the battery pack of the aforementioned embodiments.

[0022] Beneficial effect: Compared with the prior art, a battery in an embodiment of the present application has a first direction and a second direction intersecting each other, and includes a shell, an electrode assembly and a top cover assembly, the shell has a accommodating cavity, the electrode assembly is arranged in the accommodating cavity, the top cover assembly includes a top cover sheet and a lower insulating member, the top cover sheet is connected to the shell and covers the accommodating cavity, and the lower insulating member is connected to the side of the top cover sheet facing the electrode assembly; the lower insulating member includes a main body and a first protrusion, the main body has at least two first through holes arranged at intervals along the first direction; the first protrusion is connected to the side of the main body away from the top cover sheet, and is arranged between two adjacent first through holes; along the second direction, the size of the first protrusion is d mm, and the maximum distance between the main body and the electrode assembly is n mm, satisfying: 0.3≤d / n<1. The present application utilizes the first through hole to provide a channel for connecting the electrode terminal and the electrode assembly, and utilizes the first protrusion to be set between two adjacent first through holes, so as to effectively enhance the anti-deformation strength of the lower insulating member, and at the same time control 0.3≤d / n<1, so as to control the size of the first protrusion within a controllable range to ensure the sealing of the battery installation, and can abut against the electrode assembly to suppress deformation when the body is deformed toward the electrode assembly, thereby effectively improving the safety performance of the battery; in addition, it can also ensure that there is a certain gap between the first protrusion and the electrode assembly, so as to ensure that when the battery thermally runs away, the thermal runaway gas inside the accommodating cavity can flow on both sides of the first protrusion through the gap between the first protrusion and the electrode assembly, so as to avoid excessive local pressure inside the battery, and also facilitate the thermal runaway gas to flow to the explosion-proof valve, thereby improving the safety of the battery.

[0023] Compared with the prior art, a battery pack according to an embodiment of the present application includes a battery according to any one of the above embodiments. It is understandable that the battery pack according to the embodiment of the present application has all the technical features and technical effects of the above batteries, which will not be described in detail here.

[0024] Compared with the prior art, an electric device in an embodiment of the present application includes a battery as described in any one of the aforementioned embodiments, or a battery pack in the aforementioned embodiments. It can be understood that the electric device in an embodiment of the present application has all the technical features and technical effects of the aforementioned battery or battery pack, which will not be described in detail here. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0026] Figure 1 is a schematic diagram of the overall structure of a battery in an embodiment of the present application; Figure 2is an exploded diagram of a battery according to an embodiment of the present application; Figure 3 is a schematic diagram of the overall structure of the top cover assembly of an embodiment of the present application; Figure 4 is an exploded view of a top cover assembly of an embodiment of the present application; Figure 5 is a cross-sectional view of the connection between the top cover assembly and the adapter sheet of an embodiment of the present application; Figure 6 is a schematic structural diagram of a housing according to an embodiment of the present application; Figure 7 is a cross-sectional view of a housing according to an embodiment of the present application; Figure 8 is a cross-sectional view of a battery according to an embodiment of the present application; Fig. 9 is a schematic diagram of the overall structure of a lower insulating member in an embodiment of the present application; Fig.10 yes Fig. 9 A bottom view of the lower insulating member of the embodiment; Fig.11 yes Fig. 9 A top view of a lower insulating member of an embodiment; Fig.12 is a side view of a lower insulating member of an embodiment of the present application; Fig.13 is a bottom view of a second lower insulating member of an embodiment of the present application; Fig.14 is a schematic diagram of the overall structure of a third lower insulating member in an embodiment of the present application; Fig.15 is a schematic diagram of the overall structure of a fourth lower insulating member of an embodiment of the present application; Fig.16 yes Fig.15 Cross-sectional view of an embodiment.

[0027] Figure numerals: 1, shell; 11, accommodating cavity; 12, pressure relief member; 2, electrode assembly; 3, top cover assembly; 31, top cover sheet; 32, lower insulating member; 321, main body; 3211, first through hole; 3212, fourth through hole; 3213, fifth through hole; 3214, sixth through hole; 322, first protrusion; 3221, first cavity; 3222, first side wall; 3223, second through hole; 3224, second side wall; 3225, third through hole; 323, second protrusion; 3231, second cavity; 3232, third cavity; 33, electrode terminal; 34, upper insulating member; 35, sealing member; 4, adapter; 5, gap; X, first direction; Z, second direction; Y, third direction. DETAILED DESCRIPTION

[0028] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.

[0029] In the description of the present application, it should be understood that the terms "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more features. In the description of the present application, "multiple" means two or more, and at least one means one, two or more, unless otherwise clearly and specifically defined. In the description of this application, "vertical" means completely vertical at 90° or almost completely vertical, for example, an angle within the range of 80° to 100° is considered vertical. Similarly, "parallel" means completely parallel or almost completely parallel, for example, an angle within 10° of completely parallel is considered parallel.

[0030] It should also be noted that in the drawings of the present application, an arrow marked with X indicates a first direction X, an arrow marked with Z indicates a second direction Z, and an arrow marked with Y indicates a third direction Y. In the embodiment of the present application, the first direction X is the length direction of the battery, the second direction Z is the height direction of the battery, and the third direction Y is the width direction of the battery. The first direction X, the second direction Z, and the third direction Y are introduced to facilitate the description of the structural positional relationship of the various components of the battery, thereby facilitating the understanding of its structure.

[0031] In the related art, a power battery pack is usually composed of a plurality of single cells, and a single cell is generally composed of a top cover assembly, an electrode assembly, a transfer plate and a shell, etc., wherein the shell is usually an aluminum shell, which is easy to manufacture and has a relatively light overall mass. The electrode assembly is connected to the transfer plate by extending the pole ear, and the transfer plate is then connected to the electrode terminal on the top cover assembly to achieve conductivity. The top cover assembly also includes insulating plastic and a top cover sheet, and the insulating plastic is used to insulate and separate the electrode assembly from the top cover sheet, thereby avoiding internal short circuits in the battery. However, there is a transfer plate between the insulating plastic and the electrode assembly. For square shell batteries, there are generally two transfer plates, and the two transfer plates are spaced apart in the length direction. The corresponding insulating plastic extends in the length direction. The longer the length of the insulating plastic, the lower the strength in the middle, and the easier it is for the middle part to deform toward the electrode assembly, so as to further squeeze the transfer plate adjacent to the insulating plastic. At this time, the transfer plate is deformed or the connection between the transfer plate and the electrode terminal is broken, which causes the electrical connection to fail, affecting the battery performance and service life.

[0032] In view of this, an embodiment of the present application provides a battery to solve the above-mentioned problem.

[0033] Please refer to Figure 1-Figure 8 and Fig.12 The embodiment of the present application provides a battery having a first direction X and a second direction Z intersecting each other, and comprising a shell 1, an electrode assembly 2 and a top cover assembly 3, wherein the shell 1 has a receiving cavity 11, the electrode assembly 2 is arranged in the receiving cavity 11, the top cover assembly 3 comprises a top cover sheet 31 and a lower insulating member 32, the top cover sheet 31 is connected to the shell 1 and covers the receiving cavity 11, and the lower insulating member 32 is connected to a side of the top cover sheet 31 facing the electrode assembly 2; the lower insulating member 32 comprises a body 321 and a first protrusion 322, the body 321 has at least two first through holes 3211 arranged at intervals along the first direction X; the first protrusion 322 is connected to a side of the body 321 away from the top cover sheet 31, and is arranged between two adjacent first through holes 3211; along the second direction Z, the size of the first protrusion 322 is d mm, and the maximum distance between the body 321 and the electrode assembly 2 is n mm, satisfying: 0.3≤d / n<1.

[0034] In the embodiment of the present application, the first through hole 3211 is used to provide a channel for connecting the electrode terminal 33 with the electrode assembly 2. The first protrusion 322 is set between two adjacent first through holes 3211, which can effectively enhance the anti-deformation strength of the lower insulating member 32. At the same time, 0.3≤d / n<1 is controlled, and the size of the first protrusion 322 can be controlled within a controllable range to ensure the sealing of the battery installation. When the body 321 is deformed toward the electrode assembly 2, it can be connected to the electrode assembly 2 to suppress deformation, thereby improving the safety performance of the battery; in addition, it can also ensure that there is a certain gap 5 between the first protrusion 322 and the electrode assembly 2, so that when the battery thermally runs away, the thermal runaway gas inside the accommodating cavity 11 can flow on both sides of the first protrusion 322 through the gap 5 between the first protrusion 322 and the electrode assembly 2, thereby avoiding excessive local pressure inside the battery and facilitating the thermal runaway gas to flow to the explosion-proof valve, thereby improving the safety of the battery.

[0035] Specifically, by setting the ratio of the size of the first protrusion 322 and the maximum distance between the main body 321 and the electrode assembly 2 to satisfy 0.3≤d / n<1, it can be understood that d<n, thereby ensuring that there is a certain gap 5 between the first protrusion 322 and the electrode assembly 2. If the battery has thermal runaway, the thermal runaway gas in the accommodating cavity 11 can flow on both sides of the first protrusion 322 through the gap 5 between the first protrusion 322 and the electrode assembly 2, thereby facilitating the gas in the accommodating cavity 11 to reduce the pressure and flow toward the explosion-proof valve, thereby improving the safety of the battery.

[0036] In the embodiment of the present application, 0.3≤d / n<1 is set. At this time, the first protrusion 322 can not only strengthen the main body 321, but also when the deformation force of the main body 321 is too large and the first protrusion 322 cannot suppress its deformation, the main body 321 can deform toward the electrode assembly 2 with the first protrusion 322 until the first protrusion 322 and the electrode assembly 2 are offset, so as to play the role of supporting the electrode assembly 2 and the main body 321 with the first protrusion 322, thereby utilizing the supporting effect of the first protrusion 322 to further prevent the deformation of the main body 321 toward the electrode assembly 2, effectively protect the stability of the battery structure, and thus ensure the stable performance of the battery.

[0037] It should also be noted that in the embodiment of the present application, the value of d / n is in the range of [0.3~1), that is, the value can be any value among 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9, 0.95, 0.99 or a range between any two values. When the value of d / n is larger, the first protrusion 322 is closer to the electrode assembly 2, so that the lower insulating member 32 is deformed toward the electrode assembly 2 under the influence of its own weight and the force of squeezing the adapter 4 is smaller, and the possibility of the connection area of ​​the adapter 4 breaking is also smaller, and the corresponding battery safety is higher. When d / n>1, since the first protrusion 322 is disposed between the first body 321 and the electrode assembly 2, there is a risk that the top cover sheet 31 is located outside the accommodating cavity 11 and cannot be connected to the housing 1 to achieve sealing of the accommodating cavity 11, which may affect the airtightness of the battery 200. When d / n=1, the first protrusion is connected to the electrode assembly, and there is no space buffer when the body deforms toward the electrode assembly. Therefore, in the embodiment of the present application, d / n<1 is controlled. When the value of d / n is smaller, the distance between the first protrusion 322 and the electrode assembly 2 is larger, and the deformation space that the lower insulating member 32 can provide under the influence of its own weight is larger. Of course, the smaller the volume of the corresponding first protrusion 322, the smaller its gravity is, and the smaller the influence on the deformation of the lower insulating member 32 is. At the same time, the first protrusion 322 also has a reinforcing effect on the main body 321, so the stability of the battery structure can still be maintained; when d / n<0.3, the first protrusion 322 is smaller as a whole, and the corresponding reinforcing force of the first protrusion 322 is smaller, and the lower insulating member 32 has poor anti-deformation strength. Therefore, in the embodiment of the present application, 0.3≤d / n<1 is controlled.

[0038] In some embodiments, a dimension d of the first protrusion 322 satisfies: 1.5≤d<4.

[0039] It is understood that in the embodiment of the present application, the numerical range of d can be any one of 1.5, 1.6, 1.7, 1.8, 1.9, 2, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9 or the range between any two values. Among them, the larger the numerical value of d, the higher the strength of the corresponding lower insulating member 32, and the smaller the possibility of deformation of the lower insulating member 32. If d is too large, the first protrusion 322 may abut against the electrode assembly 2, resulting in failure to assemble smoothly. If d is too small, the corresponding structure may not be strengthened.

[0040] In some embodiments, the maximum distance n between the body 321 and the electrode assembly 2 satisfies: 2≤n≤5.

[0041] It can be understood that in the embodiment of the present application, the numerical range of n can be any one of 2, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, 4, 4.1, 4.2, 4.3, 4.4, 4.5, 4.6, 4.7, 4.8, 4.9, 5, or the range between any two values. First, there needs to be a certain gap between the body 321 and the electrode assembly 2 to achieve the conductive connection between the electrode assembly 2 and the electrode terminal 33. As the value of n increases, the installation space of the lower insulating member 32 will be compressed, resulting in a decrease in the anti-deformation strength of the lower insulating member 32. Therefore, the present application controls 2≤n≤5, which can not only ensure the conductive connection between the electrode assembly 2 and the electrode terminal 33, but also ensure the capacity of the battery while improving the anti-deformation strength of the lower insulating member.

[0042] In the embodiment of the present application, by limiting the size d of the first protrusion 322 and the maximum distance n between the body 321 and the electrode assembly 2 within the above range, the lower insulating member 32 can be kept with a strong anti-deformation strength, and the battery can be ensured to have a large capacity and high safety. In some embodiments, along the second direction Z, the size of the top cover sheet 31 is a mm, the size of the accommodating cavity 11 is b mm, the size of the electrode assembly 2 is c mm, and the size of the body 321 is m mm, satisfying: n=bacm, 0.3≤d / (bacm)<1.

[0043] In the embodiment of the present application, n=bacm is defined, which is equivalent to defining that the top cover sheet 31, the lower insulating member 32 and the electrode assembly 2 are all located in the accommodating cavity 11. At the same time, the upper surface of the top cover sheet 31 is coplanar with the surface of the opening of the shell 1, so as to ensure that the size of the accommodating cavity 11 along the second direction Z, excluding the electrode assembly 2, the top cover sheet 31 and the body 321, is the gap between the body 321 and the electrode assembly 2, and no additional space is wasted. At the same time, it can ensure that the top cover sheet 31 is arranged in the accommodating cavity 11 and is connected to the shell 1 to cover the accommodating cavity 11, so as to achieve the sealing of the battery. In addition, the first protrusion 322 is also used to enhance the strength of the body 321 to prevent the body 321 from deforming toward the electrode assembly 2.

[0044] Specifically, the battery of the embodiment of the present application can be a square shell battery, in which case the top cover assembly 3 includes a top cover sheet 31, a lower insulating member 32, an upper insulating member 34, an electrode terminal 33, a sealing member 35, etc. The top cover sheet 31 is a light aluminum plate, the battery shell 1 can be a square aluminum shell, and the lower insulating member 32 can be an insulating plastic. Through holes are provided on the top cover sheet 31 and the lower insulating member 32, through which the electrode terminal 33 passes, and the upper insulating member 34, the sealing member 35, etc. are used to achieve a sealed connection between the electrode terminal 33, the lower insulating member 32, and the top cover sheet 31. Among them, the lower insulating member 32 includes a main body 321, and at least two first through holes 3211 are arranged on the main body 321. Furthermore, there are preferably two first through holes 3211, and there are also two electrode terminals 33, namely a positive terminal and a negative terminal. The positive terminal and the negative terminal respectively pass through the two first through holes 3211 and through the through holes at corresponding positions on the top cover sheet 31. Among them, the upper insulating member 34 and the sealing member 35 are sleeved on the outside of the electrode terminal 33 to realize the sealed connection between the electrode terminal 33 and the top cover sheet 31.

[0045] It should be noted that the electrode terminal 33 has a limiting portion at one end facing the electrode assembly 2 , and the limiting portion is arranged on the side of the body 321 facing the electrode assembly 2 , so as to provide a supporting and limiting function for the lower insulating member 32 .

[0046] Furthermore, the present application sets a first protrusion 322 between two adjacent first through holes 3211, which can provide a reinforcement between the two electrode terminals 33 to improve the structural strength of the main body 321 at that location, thereby providing resistance to the deformation of the main body 321 toward the electrode assembly 2, and effectively preventing the part of the main body 321 between the two adjacent first through holes 3211 from deforming toward the electrode assembly 2, thereby ensuring the stability of the overall structure of the battery, avoiding the main body 321 from squeezing the adapter 4, thereby effectively preventing the adapter 4 from deforming, and avoiding the connection between the adapter 4 and the electrode terminal 33 from breaking, effectively ensuring the stability of the internal electrical connection of the battery, and ensuring the battery performance and service life.

[0047] Furthermore, the embodiment of the present application also provides that the top cover sheet 31 and the lower insulating member 32 of the top cover assembly 3 are both arranged in the accommodating cavity 11 of the shell 1, and the corresponding body 321 and the first protrusion 322 are both arranged in the accommodating cavity 11. Since the adapter sheet 4, the first protrusion 322 and other structures are arranged between the electrode assembly 2 and the body 321, there is a gap between the body 321 and the electrode assembly 2. Therefore, along the second direction Z, i.e., the height direction of the battery, the size of the accommodating cavity 11 minus the size of the top cover sheet 31, the size of the body 321 and the size of the electrode assembly 2 needs to be greater than or equal to the size of the first protrusion 322, so that the top cover sheet 31 can be kept arranged in the accommodating cavity 11 and connected to the shell 1 to cover the accommodating cavity 11, so as to achieve the sealing of the battery. At the same time, the first protrusion 322 is also used to enhance the strength of the body 321 to prevent the body 321 from deforming toward the electrode assembly 2.

[0048] Furthermore, the embodiment of the present application sets 0.3≤d / (bacm)<1, which is equivalent to the numerical range of the ratio of the size of the first protrusion 322 to the size of the accommodating cavity 11 minus the size of the top cover sheet 31, the size of the body 321 and the size of the electrode assembly 2 along the second direction Z, which is 0.3~1. At this time, the first protrusion 322 can not only strengthen the body 321 and improve the anti-deformation strength of the lower insulating member 32, but also when the deformation force of the body 321 is too large and the first protrusion 322 cannot suppress its deformation, the body 321 can deform toward the electrode assembly 2 with the first protrusion 322 until the first protrusion 322 and the electrode assembly 2 are offset, so as to play the role of supporting the electrode assembly 2 and the body 321 with the first protrusion 322, thereby utilizing the supporting role of the first protrusion 322 to further prevent the deformation of the body 321 toward the electrode assembly 2, effectively protect the stability of the battery structure, and thus ensure the stability of the battery performance.

[0049] It should be noted that in the square shell battery, the first protrusion 322 is preferably arranged in the middle area of ​​the body 321. In this case, the first protrusion 322 can be used to effectively suppress the deformation of the middle area of ​​the body 321. Furthermore, when the middle area of ​​the lower insulating member 32 sinks and deforms due to its own weight, the first protrusion 322 contacts the electrode assembly 2, which can suppress the deformation, so as to prevent the body 321 from deforming and squeezing the adapter 4 connected to the electrode terminal 33, thereby preventing the adapter 4 from breaking and failing in the connection area.

[0050] It should also be noted that the larger the value of d / (bacm), the closer the corresponding first protrusion 322 is to the electrode assembly 2. At this time, the force of the lower insulating member 32 deforming toward the electrode assembly 2 under the influence of its own weight and squeezing the adapter 4 is smaller, the overall structure of the battery is more stable, and thus the battery performance is more stable, which effectively ensures the service life of the battery.

[0051] It should also be noted that in the embodiment of the present application, the value of d / (bacm) is in the range of [0.3~1), that is, the value can be any value among 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9, 0.95, 0.99 or a range between any two values. When the value of d / (bacm) is larger, the first protrusion 322 is closer to the electrode assembly 2, so that the lower insulating member 32 is deformed toward the electrode assembly 2 under the influence of its own weight and the force of squeezing the adapter 4 is smaller, and the possibility of the connection area of ​​the adapter 4 breaking is also smaller, and the corresponding battery safety is higher. When d / (bacm)>1, since the first protrusion 322 is disposed between the first body 321 and the electrode assembly 2, there is a risk that the top cover sheet 31 is located outside the accommodating cavity 11 and cannot be connected to the housing 1 to achieve sealing of the accommodating cavity 11, which may affect the airtightness of the battery 200. When d / (bacm)=1, the first protrusion is connected to the electrode assembly, and there is no space buffer when the body deforms toward the electrode assembly. Therefore, in the embodiment of the present application, d / (bacm) is controlled to be less than 1. When the value of d / (bacm) is smaller, the distance between the first protrusion 322 and the electrode assembly 2 is larger, and the deformation space that the lower insulating member 32 can provide under the influence of its own weight is larger. Of course, the smaller the volume of the corresponding first protrusion 322, the smaller its gravity is, and the smaller the influence on the deformation of the lower insulating member 32 is. At the same time, the first protrusion 322 also has a reinforcing effect on the main body 321, so the stability of the battery structure can still be maintained; when d / (bacm) is less than 0.3, either the battery capacity will be smaller, or the first protrusion 322 will be smaller as a whole, and the corresponding reinforcing force of the first protrusion 322 will be smaller, and the lower insulating member will have insufficient anti-deformation strength. Therefore, in the embodiment of the present application, d / (bacm) is controlled to be ≥0.3.

[0052] It should also be noted that in the above relationship, the corresponding dimensions a, b, c, d, and m can all be directly measured using dimensional measuring tools such as a ruler, a vernier caliper, a micrometer, and the like.

[0053] In some embodiments, the dimension a of the top cover sheet 31 satisfies: 1.5≤a≤2.5.

[0054] It is understood that in the embodiment of the present application, the numerical range of a can be any value in 1.5, 1.51, 1.52, 1.53, 1.54, 1.55, 1.56, 1.57, 1.58, 1.59, 1.6, 1.62, 1.65, 1.68, 1.7, 1.75, 1.8, 1.85, 1.9, 1.95, 2.0, 2.05, 2.1, 2.15, 2.2, 2.25, 2.3, 2.35, 2.4, 2.45, 2.5 or the range between any two values. In the embodiment of the present application, if a is too small, the top cover sheet 31 will be easy to deform with low strength, and if a is too large, the overall weight of the battery will increase, affecting the energy density of the battery. Therefore, the range of a is controlled to meet 1.5≤a≤2.5, at which time the strength of the top cover sheet 31 meets the demand and does not affect the energy density of the battery.

[0055] In some embodiments, the size b of the accommodating cavity 11 satisfies: 60≤b≤300.

[0056] It can be understood that in the embodiment of the present application, the value range of b can be any value in 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 75, 80, 85, 90, 95, 100, 105, 110, 115, 120, 125, 130, 135, 140, 145, 150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300, or a range value between any two values. By controlling b to meet the above range, it can be ensured that the battery has a relatively reasonable accommodation space, and at this time, it can be ensured that the battery can accommodate a larger size of electrode assembly, thereby ensuring the capacity of the battery.

[0057] In some embodiments, the dimension c of the electrode assembly 2 satisfies: 53.7≤c≤291.

[0058] It can be understood that in the embodiment of the present application, the numerical range of c can be any value among 53.7, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 75, 80, 85, 90, 95, 100, 105, 110, 115, 120, 125, 130, 135, 140, 145, 150, 155, 160, 165, 170, 175, 180, 185, 190, 195, 200, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 291, or the range between any two values. Among them, when c meets the above range, the electrode assembly 2 can ensure a reasonable capacity to ensure the volume energy density of the secondary battery.

[0059] In some embodiments, a dimension m of the body 321 satisfies: 0.3≤m≤2.

[0060] It can be understood that in the embodiment of the present application, the value range of m can be any value in 0.3, 0.31, 0.32, 0.33, 0.34, 0.35, 0.36, 0.37, 0.38, 0.39, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9, 0.95, 1, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2, or a range between any two values. When m satisfies the above range, it is ensured that the body 321 has a certain thickness, so that it can have a certain strength, ensure the stability of the overall structure of the lower insulating member 32, and have a good insulation effect.

[0061] It should also be noted that in the embodiments of the present application, dimensions a, b, c, and m can also be directly measured using dimension measuring tools such as a ruler, a vernier caliper, a micrometer, and the like.

[0062] In some embodiments, 0.015≤n / c≤0.084 is satisfied.

[0063] In the embodiment of the present application, it is limited to 0.015≤n / c≤0.084, that is, the ratio of the maximum dimension between the main body 321 and the electrode assembly 2 to the dimension of the electrode assembly 2 along the second direction Z is in the range of 0.015~0.084. At this time, it can avoid the maximum dimension between the main body 321 and the electrode assembly 2 being too large, which leads to a reduction in the anti-deformation strength of the lower insulating member. At the same time, it can avoid the maximum dimension between the main body 321 and the electrode assembly 2 being too small, which leads to a too small bending space of the pole ear. Furthermore, it can avoid the thickness of the pole ear to be bent being too small, and can ensure a certain overcurrent resistance, thereby avoiding excessive temperature rise during battery charging, and effectively ensuring the safety performance of the battery.

[0064] It should be noted that, in the embodiment of the present application, the value of n / c is within the range of 0.015 to 0.084, that is, the value can be any value among 0.015, 0.016, 0.017, 0.018, 0.019, 0.02, 0.022, 0.024, 0.026, 0.028, 0.029, 0.03, 0.035, 0.04, 0.045, 0.05, 0.06, 0.07, 0.08, 0.084 or a range between any two values. When n / c>0.084, due to the limited space of the accommodating cavity 11 of the housing 1, the corresponding space of the lower insulating member 32 is small, and the corresponding first protrusion is also small, which affects the anti-deformation strength of the lower insulating member 32. Therefore, in the embodiment of the present application, n / c is controlled to be ≤0.084. When n / c<0.015, the corresponding space available for bending the pole ear is smaller, the thickness of the corresponding pole ear to be bent will be smaller, the overcurrent resistance will be smaller, the current energy will be greater, the charging temperature rise of the battery will be higher, and the battery safety performance will decrease. Therefore, in the embodiment of the present application, n / c≥0.015 is controlled.

[0065] It should also be noted that, in the embodiments of the present application, the dimension e can also be directly measured using dimension measuring tools such as a ruler, a vernier caliper, a micrometer, and the like.

[0066] Please refer to Figure 5 , Figure 9-11 and Fig.13 In some embodiments, the first protrusion 322 has a first cavity 3221 , the body 321 has a fourth through hole 3212 , and the first cavity 3221 is connected to the fourth through hole 3212 .

[0067] In the embodiment of the present application, a first cavity 3221 is provided in the first protrusion 322 , which can, on the one hand, enhance the strength of the lower insulating member 32 at the first protrusion 322 and improve its deformation resistance, while at the same time effectively reducing the weight of the first protrusion 322 , thereby reducing the increase in deformation force caused by the self-weight of the lower insulating member 32 .

[0068] Furthermore, in the embodiment of the present application, a fourth through hole 3212 is also provided on the main body 321 , and the first cavity 3221 is connected to the fourth through hole 3212 , which further reduces the deadweight of the lower insulating member 32 and further reduces the deformation force on the electrode assembly 2 .

[0069] In addition, it should be noted that since the lower insulating member 32 can be an insulating plastic, the plastic itself has the property of shrinkage. During processing, the thicker the material in the local area, the easier it is to shrink. Therefore, the present application makes the body 321 as thin as possible while ensuring the insulation performance, and then uses the protrusion to support between the body 321 and the electrode assembly 2 to ensure the stability of the battery structure. Among them, the material thickens at the connection between the first protrusion 322 and the body 321. Therefore, the first protrusion 322 corresponding to the embodiment of the present application has a first cavity 3221, and the body 321 has a fourth through hole 3212. The first cavity 3221 is connected to the fourth through hole 3212. At this time, the material thickness of the first protrusion 322 can be effectively reduced, and the material thickness at the connection between the first protrusion 322 and the body 321 can also be reduced, thereby effectively preventing the lower insulating member 32 from shrinking during processing, and effectively ensuring that the size error of the lower insulating member 32 is within the allowable range.

[0070] Furthermore, in the embodiment of the present application, the first cavity 3221 and the fourth through hole 3212 are arranged relatively to each other along the second direction Z. Further preferably, the opening area of ​​the first cavity 3221 is the same as the opening area of ​​the fourth through hole 3212. In this case, it is convenient for the lower insulating member 32 to be integrally formed, and it is also convenient for the side wall of the first protrusion 322 to reinforce the hole wall portion of the fourth through hole 3212 on the main body 321, thereby preventing local deformation of the hole wall portion of the fourth through hole 3212.

[0071] like Fig.14 As shown, in some embodiments, the first protrusion 322 includes a first side wall 3222 facing the electrode assembly 2 , the first side wall 3222 has at least one second through hole 3223 , and the second through hole 3223 is connected to the first cavity 3221 .

[0072] In the embodiment of the present application, at least one second through hole 3223 is provided on the first side wall 3222, and the second through hole 3223 is kept in communication with the first cavity 3221. This structural setting can, on the one hand, further reduce the weight of the first protrusion 322, and avoid deformation of the lower insulating member 32 caused by shrinkage of the first protrusion 322 during processing; on the other hand, it can absorb the deformation force generated by thermal expansion and contraction when the battery is used, thereby reducing the force of the lower insulating member 32 on the electrode terminal 33 and the adapter 4. It should be noted that the first protrusion 322 can be spaced apart from the electrode assembly 2.

[0073] At the same time, the first cavity 3221 can be connected to the accommodating cavity 11 through the second through hole 3223, so that when the battery has thermal runaway, the thermal runaway gas in the accommodating cavity 11 flows into the first cavity 3221, expanding the flow space of the gas. Of course, at this time, the pressure relief member (explosion-proof valve) of the battery can be set on the top cover sheet 31 and opposite to the first cavity 3221. When the gas pressure of the thermal runaway gas in the battery exceeds the preset value, it can break through the pressure relief member and release pressure to the outside to prevent the battery from exploding. At this time, the electrode assembly 2 is spaced apart from the first protrusion 322.

[0074] Please refer to Fig.15 and Fig.16 In some embodiments, the first protrusion 322 includes a second side wall 3224 arranged opposite to each other along the first direction X, the second side wall 3224 intersects with the first side wall 3222, and the second side wall 3224 is provided with at least one third through hole 3225, and the third through hole 3225 is connected to the first cavity 3221.

[0075] In the embodiment of the present application, the second side walls 3224 of the first protrusion 322 that are relatively arranged along the first direction X are designed with third through holes 3225, and the third through holes 3225 are connected to the first cavity 3221. At this time, the space on both sides of the first protrusion 322 can be connected, and the electrolyte or the gas in the battery can flow on both sides of the first protrusion 322 through the third through holes 3225 and the first cavity 3221.

[0076] Furthermore, there are a plurality of third through holes 3225 , which can maintain the structural stability of the first protrusion 322 and keep the spaces on both sides of the first protrusion 322 connected.

[0077] The third through hole 3225 is provided to facilitate the thermal runaway gas inside the battery to flow from one side of the first protrusion 322 to the other side, and then be discharged from the exhaust valve, thereby avoiding the situation where the local pressure inside the battery is too high and cannot be exhausted.

[0078] Furthermore, in some embodiments, the area of ​​the second side wall 3224 is S1mm 2 The area of ​​the third through hole 3225 on the second side wall 3224 is S2 mm 2 , satisfying: 0.3≤S2 / S1≤0.7.

[0079] In the embodiment of the present application, the ratio of the opening area of ​​the third through hole 3225 to the area of ​​the second side wall 3224 is set to 0.3~0.7, which can avoid the exhaust rate being too slow due to the total area of ​​the third through hole 3225 being too small, and avoid the overall structural strength of the first protrusion 322 being reduced due to the total area of ​​the third through hole 3225 being too large, which makes the first protrusion 322 easy to deform.

[0080] It should be noted that in the embodiments of the present application, the value of S2 / S1 is in the range of 0.3~0.7, that is, the value can be any value in 0.3, 0.31, 0.32, 0.33, 0.34, 0.35, 0.36, 0.37, 0.38, 0.39, 0.40, 0.41, 0.42, 0.43, 0.44, 0.45, 0.46, 0.47, 0.48, 0.49, 0.50, 0.51, 0.52, 0.53, 0.54, 0.55, 0.56, 0.57, 0.58, 0.59, 0.60, 0.61, 0.62, 0.63, 0.64, 0.65, 0.66, 0.67, 0.68, 0.69, 0.7, or the range between any two values. When the value of S2 / S1 is larger, the area of ​​the corresponding third through hole 3225 is larger, the airflow flow path on both sides of the first protrusion 322 is larger, and the corresponding exhaust rate is faster. When S2 / S1>0.7, it means that the opening area of ​​the third through hole 3225 is relatively too large, which may affect the overall structural strength of the first protrusion 322, causing the first protrusion 322 to be easily deformed. Therefore, in the embodiment of the present application, S2 / S1 is controlled to be ≤0.7. When the value of S2 / S1 is smaller, the area of ​​the corresponding third through hole 3225 is smaller, the airflow path on both sides of the first protrusion 322 is smaller, the corresponding exhaust rate is slower, and the possibility of local excessive air pressure during thermal runaway of the corresponding battery is higher; when S2 / S1 is less than 0.3, the total opening area of ​​the third through hole 3225 is too small, and the airflow rate on both sides of the first protrusion 322 is too slow, which affects the airflow on both sides of the first protrusion 322 and is not conducive to the exhaust of the battery during thermal runaway. Therefore, in the embodiment of the present application, S2 / S1 is controlled to be ≥0.3.

[0081] It should also be noted that, in the above relationship, the area S1 of the second side wall 3224 and the area S2 of the third through hole 3225 can be measured and calculated by conventional area measurement methods. For example, if the second side wall 3224 and the third through hole 3225 are both regular shapes (such as square, circular, elliptical, ring-shaped, etc.), the area measurement method of the corresponding shape can be used for measurement and calculation; if the second side wall 3224 and the third through hole 3225 are irregular shapes, the coating method can be used for measurement and calculation. For the calculation of the area S1 of the second side wall 3224, a film of uniform mass can be attached to the second side wall 3224, the film corresponding to the shape of the second side wall 3224 can be removed, and the mass of the film can be determined. The quotient of the mass of the removed film and the mass per unit area of ​​the film that has been predetermined is determined as the area S1 of the second side wall 3224. For the calculation of the area S2 of the third through hole 3225, a film of uniform mass can be attached to the second side wall 3224 corresponding to the third through hole 3225, the film attached to the corresponding part of the third through hole 3225 can be removed, and the mass of the film can be determined. The quotient of the mass of the removed film and the mass per unit area of ​​the film that has been predetermined is determined as the area S2 of the measured third through hole 3225.

[0082] Please refer to Figure 9-11 and Fig.13 In some embodiments, a third direction Y intersecting the first direction X and the second direction Z respectively is provided, and the lower insulating member 32 includes a plurality of the first protrusions 322 , and at least two of the first protrusions 322 are spaced apart along the third direction Y.

[0083] In the embodiment of the present application, there may be one or more first protrusions 322. When there are multiple first protrusions 322, preferably at least two first protrusions 322 are arranged at intervals along the third direction Y. In this way, the body 321 can be supported by multiple first protrusions 322 at the same position along the first direction X (length direction), effectively ensuring the support stability. At the same time, there is a gap between two adjacent first protrusions 322 along the third direction Y. At this time, the gap can realize the function of connecting the aforementioned third through hole 3225 with the first cavity 3221, that is, the gap can realize the space connection on both sides of the first protrusion 322 along the first direction X, ensuring the internal gas circulation of the battery, and avoiding the situation where the local gas pressure is too high to be discharged.

[0084] It should be noted that, in the embodiment of the present application, the multiple first protrusions 322 may all have a first cavity 3221, and at the portion connected to the main body 321, the main body 321 is provided with a fourth through hole 3212 to communicate with the first cavity 3221, thereby reducing the local material thickness of the lower insulating member 32 and preventing the lower insulating member 32 from shrinking and deforming during processing.

[0085] like Fig. 9 and Fig.13 As shown, in some embodiments, along the third direction Y, the first cavities 3221 of two adjacent first protrusions 322 penetrate the opposite side walls of the two first protrusions 322 .

[0086] In the embodiment of the present application, along the third direction Y, the first cavity 3221 of two adjacent first protrusions 322 penetrates the opposing side walls thereof. At this time, while ensuring the reinforcement and supporting functions thereof, the use of the material of the first protrusion 322 can be further reduced, thereby further reducing the possibility of shrinkage and deformation of the lower insulating member 32 during processing.

[0087] Please refer to Figure 3 , Figure 5 , Figure 8-Figure 15 In some embodiments, the lower insulating member 32 further includes at least two second protrusions 323 spaced apart along the first direction X, and the second protrusions 323 are connected to the side of the body 321 facing the electrode assembly 2; along the first direction X, the first protrusions 322 are spaced apart between two adjacent second protrusions 323, and at least one first through hole 3211 is provided between the first protrusion 322 and the second protrusion 323, and the side of the second protrusion 323 away from the body 321 abuts against the electrode assembly 2.

[0088] In the embodiment of the present application, by providing a plurality of second protrusions 323, support can be provided between the main body 321 and the electrode assembly 2, thereby further achieving stability of the overall structure of the lower insulating member 32 in the accommodating cavity 11 of the battery, and preventing the portion without the first protrusion 322 and the electrode terminal 33 from deforming toward the electrode assembly 2.

[0089] Preferably, there are two second protrusions 323, and the two second protrusions 323 are respectively arranged at both ends of the main body 321 along the first direction X, so as to effectively support the main body 321 and prevent the main body 321 from deforming toward the electrode assembly 2. At the same time, the second protrusion 323 is used to abut the electrode assembly 2, so as to achieve effective limiting and fixing of the electrode assembly 2, and avoid shaking of the electrode assembly 2 in the accommodating cavity 11, thereby reducing the bending and squeezing of the pole ear, maintaining the overall performance of the battery stable, and further ensuring the service life of the battery.

[0090] Please refer to Figure 8 and Fig.12 In some embodiments, along the second direction Z, the size of the second protrusion 323 is e mm, satisfying: d<e, e=n, and 0.015≤e / c≤0.084.

[0091] In the embodiment of the present application, e=n, and n=bacm, therefore, e=n=bacm. That is, along the second direction Z, the size of the second protrusion 323 is equal to the distance between the body 321 and the electrode assembly 2, that is, the second protrusion 323 is connected to the first body 321, and the second protrusion 323 contacts the electrode assembly 2 on the side facing the electrode assembly 2, so that the electrode assembly 2 can be prevented from moving in the second direction Z.

[0092] Furthermore, in the embodiment of the present application, it is limited to 0.015≤e / c≤0.084, that is, the numerical range of the ratio of the size of the second protrusion 323 along the second direction Z to the size of the electrode assembly 2 along the second direction Z is 0.015~0.084. At this time, it can avoid the reduction of battery capacity due to the second protrusion 323 being too large and the bending space of the pole ear being too small due to the second protrusion 323 being too small, thereby avoiding the thickness of the pole ear to be bent being too small, and ensuring a certain overcurrent resistance, thereby avoiding excessive temperature rise during battery charging, and effectively ensuring the safety performance of the battery.

[0093] In addition, since one end of the second protrusion 323 is connected to the body 321 along the second direction Z, and the other end of the second protrusion 323 abuts against the electrode assembly 2, there is a gap between the first protrusion 322 and the electrode assembly 2, the size of the first protrusion 322 is smaller than the size of the second protrusion 323.

[0094] It should be noted that, in the embodiment of the present application, the value of e / c is within the range of 0.015 to 0.084, that is, the value can be any value among 0.015, 0.016, 0.017, 0.018, 0.019, 0.02, 0.022, 0.024, 0.026, 0.028, 0.029, 0.03, 0.035, 0.04, 0.045, 0.05, 0.06, 0.07, 0.08, 0.084, or a range value between any two values. When e / c>0.084, due to the limited space of the accommodating cavity 11 of the housing 1, the corresponding space of the lower insulating member 32 is small, and the corresponding first protrusion is also small, which affects the anti-deformation strength of the lower insulating member 32. Therefore, in the embodiment of the present application, e / c is controlled to be ≤0.015. When e / c is less than 0.015, the space available for bending the corresponding pole ear is reduced, the thickness of the corresponding pole ear to be bent is also reduced, the overcurrent resistance is reduced, the current energy is increased, the charging temperature of the battery is increased, and the battery safety performance is reduced. Therefore, in the embodiment of the present application, e / c is controlled to be ≥ 0.015.

[0095] It should also be noted that, in the embodiments of the present application, the dimension e can also be directly measured using dimension measuring tools such as a ruler, a vernier caliper, a micrometer, and the like.

[0096] In some embodiments, the second protrusion 323 has a second cavity 3231 and a third cavity 3232 spaced apart along the third direction Y, the body 321 has a fifth through hole 3213 and a sixth through hole 3214, the second cavity 3231 is connected to the fifth through hole 3213, the third cavity 3232 is connected to the sixth through hole 3214, and the third cavity 3232 passes through the side of the second protrusion 323 away from the first protrusion 322 along the first direction X.

[0097] In the embodiment of the present application, by connecting the second cavity 3231 with the fifth through hole 3213 and the third cavity 3232 with the sixth through hole 3214, the material thickness at the connection between the second protrusion 323 and the main body 321 can be further reduced, thereby effectively avoiding shrinkage of the lower insulating member 32 during processing while ensuring support, and further reducing the possibility of deformation of the lower insulating member 32; at the same time, it can also reduce the overall weight of the battery and improve the energy density of the battery.

[0098] In some embodiments, along the second direction Z, the second cavity 3231 and the third cavity 3232 penetrate the side wall of the second protrusion 323 toward the electrode assembly 2 .

[0099] In the embodiment of the present application, the setting of this structure can further reduce the use of material for the second protrusion 323. On the one hand, it can reduce the possibility of shrinkage of the lower insulating member 32 during processing. On the other hand, it can also absorb deformation force when the battery expands and contracts due to temperature changes.

[0100] In some embodiments, a pressure relief member is disposed on the shell 1 , and the pressure relief member is spaced apart from the electrode assembly 2 along the second direction Z.

[0101] In the embodiment of the present application, the battery is provided with a pressure relief member 12 for timely opening and releasing pressure when the battery is in thermal runaway, wherein the pressure relief member 12 may be an explosion-proof valve. The pressure relief member 12 is spaced apart from the electrode assembly 2. At this time, when the battery is in thermal runaway, the thermal runaway gas can reach the pressure relief member 12 through the gap 5 between the pressure relief member 12 and the electrode assembly 2, thereby realizing the opening and releasing of pressure by the pressure relief member 12. Therefore, by spaced apart from the electrode assembly 2, the safety of the battery can be improved.

[0102] Specifically, in the embodiment of the present application, the pressure relief member 12 can be arranged on the top cover sheet 31. At this time, the pressure relief member 12 is located on the side of the lower insulating member 32 away from the electrode assembly 2, and the pressure relief member 12 is spaced apart from the electrode assembly 2. The pressure relief member 12 can also be arranged on the bottom wall of the housing 1, and the pressure relief member 12 is located on the side of the electrode assembly 2 away from the lower insulating member 32. At this time, the battery is bottom-vented, and it is still necessary to ensure that the electrode assembly 2 and the pressure relief member 12 are spaced apart. Only in this way can the thermal runaway gas be discharged smoothly. When the battery adopts the bottom exhaust scheme, the present application sets the ratio of the size d of the first protrusion 322 to the size m of the maximum distance between the body 321 and the electrode assembly 2 to satisfy: 0.3≤d / n<1, thereby ensuring that there is a gap 5 between the first protrusion 322 and the electrode assembly 2. At this time, on the one hand, the first protrusion 322 is used to improve the structural strength of the lower insulating member 32 and improve the deformation resistance of the lower insulating member 32. On the other hand, the space on both sides of the first protrusion 322 along the first direction X can be connected. At this time, if the battery has thermal runaway, the thermal runaway gas can flow from one side of the first protrusion 322 to the other side along the first direction X, thereby realizing the connection of the remaining space of the internal accommodating cavity 11 of the battery, increasing the flow path of the thermal runaway gas, thereby facilitating the thermal runaway gas to quickly flow to the side where the pressure relief member 12 is located, and realizing the rapid opening of the pressure relief member 12 to relieve pressure, thereby improving safety.

[0103] In the embodiment of the present application, the battery is preferably bottom-vented, and in this case the first protrusion 322 can be set at any position in the middle of the body 321 without affecting the exhaust during thermal runaway.

[0104] Next, specific embodiments and comparative examples of the battery of the present application are provided, and the present application is described in more detail through the specific embodiments and comparative examples, as shown in Table 1.

[0105] Among them, the lower insulating part deformation resistance strength test: use a tensile testing machine to pull the first protrusion of the lower insulating part until the middle area of ​​the lower insulating part deforms downward, and record the pulling force value.

[0106] The formula for battery capacity is: Capacity (c) = current (I) * time (t). The capacity can be calculated by charging current * full charge time. The overcurrent resistance of the tab can be tested by a resistance tester to test the resistance of the tab.

[0107] Safety performance test: When the battery is in the 1c / 1c charge and discharge state, a temperature sensor is placed on the electrode assembly to monitor the temperature of the electrode assembly in real time during battery charging and discharging. When the temperature of the electrode assembly does not exceed 60°C, the safety performance test passes. If the temperature of the electrode assembly exceeds 60°C, the safety performance test fails.

[0108] Table 1

[0109] It can be seen from the above embodiments and comparative examples that, under the condition of 0.3≤d / n<1, or 0.3≤d / (bacm)<1, it can be ensured that it can pass the battery safety performance test, maintain the good safety performance of the battery, and at the same time ensure that the battery capacity is maintained and the battery energy density is improved; it can ensure the anti-deformation strength of the lower insulating member, and at the same time ensure that the gas on both sides of the first protrusion 322 inside the battery can circulate, thereby improving the safety of the battery.

[0110] By keeping 0.015≤n / c≤0.084, or 0.015≤e / c≤0.084, that is, 0.015≤(bacm) / c≤0.084, the battery can be guaranteed to have an ideal capacity, that is, a better volume energy density. At the same time, it can also improve the problem of excessive temperature of the battery during charging caused by the overcurrent resistance of the tab being too small, thereby effectively ensuring the safety performance of the battery.

[0111] Accordingly, a battery pack described in an embodiment of the present application includes a battery described in any one of the aforementioned embodiments.

[0112] It can be understood that the battery pack of the embodiment of the present application has all the technical features and technical effects of the aforementioned battery, which will not be repeated here.

[0113] Accordingly, an electrical device according to an embodiment of the present application includes the battery described in any one of the aforementioned embodiments, or the battery pack of the aforementioned embodiments.

[0114] It can be understood that the electrical device of the embodiment of the present application has all the technical features and technical effects of the aforementioned battery or battery pack, which will not be repeated here.

[0115] Of course, the electrical devices referred to in this application may be application devices such as vehicles, mobile phones, portable devices, laptops, ships, spacecraft, electric toys and electric tools. Vehicles may be new energy vehicles, which may be pure electric vehicles, hybrid electric vehicles or extended-range vehicles, etc.; spacecraft include airplanes, rockets, space shuttles and spacecrafts, etc.; electric toys include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys and electric airplane toys, etc.; electric tools include metal cutting electric tools, grinding electric tools, assembly electric tools and railway electric tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators and electric planers, etc. The embodiments of this application do not impose any special restrictions on the above-mentioned electrical devices.

[0116] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0117] The above is a detailed introduction to a battery and a battery pack provided in the embodiments of the present application, and specific examples are used to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the technical solution and its core idea of ​​the present application; ordinary technicians in this field should understand that: they can still modify the technical solutions recorded in the aforementioned embodiments, or replace some of the technical features therein with equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A battery, characterized in that: Having an intersecting first direction and a second direction, comprising: A housing having a receiving cavity; An electrode assembly, disposed in the accommodating cavity; A top cover assembly comprises a top cover sheet and a lower insulating member, wherein the top cover sheet is connected to the shell and covers the accommodating cavity, and the lower insulating member is connected to the side of the top cover sheet facing the electrode assembly; the lower insulating member comprises a main body and a first protrusion, and the main body has at least two first through holes spaced apart along the first direction; the first protrusion is connected to the side of the main body away from the top cover sheet and is arranged between two adjacent first through holes; along the second direction, the size of the first protrusion is d mm, and the maximum distance between the main body and the electrode assembly is n mm, satisfying: 0.3≤d / n<1.

2. The battery according to claim 1, characterized in that The size d mm of the first protrusion satisfies: 1.5≤d<4; and / or, A maximum distance n between the body and the electrode assembly satisfies: 2≤n≤5.

3. The battery according to claim 2, characterized in that Along the second direction, the size of the top cover sheet is a mm, the size of the accommodating cavity is b mm, the size of the electrode assembly is c mm, and the size of the body is m mm, satisfying: n=bacm, 0.3≤d / (bacm)<1.

4. The battery according to claim 3, characterized in that The size a mm of the top cover sheet satisfies: 1.5≤a≤2.5; and / or, The size b mm of the accommodating cavity satisfies: 60≤b≤300; and / or, The size c mm of the electrode assembly satisfies: 53.7≤c≤291; and / or, The dimension m mm of the body satisfies: 0.3≤m≤2.

5. The battery according to claim 4, characterized in that Satisfies: 0.015≤n / c≤0.

084.

6. The battery according to claim 5, characterized in that The first protrusion has a first cavity, the body has a fourth through hole, and the first cavity is communicated with the fourth through hole.

7. The battery according to claim 6, characterized in that The first protrusion includes a first side wall facing the electrode assembly, the first side wall has at least one second through hole, and the second through hole is connected to the first cavity.

8. The battery according to claim 7, characterized in that The first protrusion includes a second side wall oppositely arranged along the first direction, the second side wall intersects with the first side wall, the second side wall is provided with at least one third through hole, and the third through hole is connected to the first cavity.

9. The battery according to claim 8, characterized in that The area of ​​the second side wall is S1 mm 2 The area of ​​the third through hole on the second side wall is S2 mm 2 , satisfying: 0.3≤S2 / S1≤0.

7.

10. The battery according to claim 9, characterized in that The area of ​​the second side wall is S1 mm 2 Satisfies: 20≤S1≤800; and / or, The area of ​​the third through hole on the second side wall is S2 mm 2 Satisfies: 6≤S2≤560.

11. The battery according to claim 6, characterized in that The lower insulating member has a third direction intersecting the first direction and the second direction respectively, and the lower insulating member includes a plurality of the first protrusions, and at least two of the first protrusions are arranged at intervals along the third direction.

12. The battery according to claim 11, characterized in that Along the third direction, the first cavities of two adjacent first protrusions penetrate the opposite side walls of the two first protrusions.

13. The battery according to claim 11, characterized in that The lower insulating member also includes at least two second protrusions spaced apart along the first direction, the second protrusions being connected to a side of the body facing the electrode assembly; along the first direction, the first protrusions are spaced apart between two adjacent second protrusions, and at least one first through hole is disposed between the first protrusions and the second protrusions.

14. The battery according to claim 13, characterized in that Along the second direction, the size of the second protrusion is e mm, satisfying: d<e, e=n, and 0.015≤e / c≤0.

084.

15. The battery according to claim 14, characterized in that The second protrusion has a second cavity and a third cavity arranged at intervals along the third direction, the body has a fifth through hole and a sixth through hole, the second cavity is connected to the fifth through hole, the third cavity is connected to the sixth through hole, and the third cavity passes through the side of the second protrusion away from the first protrusion along the first direction.

16. The battery according to claim 15, characterized in that Along the second direction, the second cavity and the third cavity penetrate the side wall of the second protrusion toward the electrode assembly.

17. The battery according to any one of claims 1 to 16, characterized in that: The shell is provided with a pressure relief member, and the pressure relief member is spaced apart from the electrode assembly along the second direction.

18. A battery pack, characterized in that: Comprising a battery as claimed in any one of claims 1 to 17.

19. An electrical device, characterized in that: Comprising a battery as described in any one of claims 1 to 17, or a battery pack as described in claim 18.

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