Secondary battery, battery pack, and electronic device

Abstract

The utility model provides a kind of secondary battery, battery pack and electronic device;The secondary battery includes shell, electrode assembly, pole, first insulating piece and sealing layer;Shell includes end wall and the side wall around end wall, end wall is provided with pole hole;Electrode assembly is set in shell interior;Pole includes columnar portion and first limiting portion, columnar portion penetrates pole hole, first limiting portion is located in shell interior, and by columnar portion to the outer periphery of end wall extends;First insulating piece surrounds columnar portion, and at least part is clamped between first limiting portion and end wall;At least one sealing layer is arranged around columnar portion;Sealing layer is located between end wall and first insulating piece, and / or, between first limiting portion and first insulating piece;The projection of first insulating piece, sealing layer, first limiting portion and end wall in the thickness direction of end wall at least partially coincides with each other, and sealing layer is the sealant layer that can be elastically compressed, can improve the sealing performance of secondary battery.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to a secondary battery, battery pack and electronic device. Background Technology

[0002] In the manufacturing process of a single battery cell, the sealing performance between the terminals and the casing plays a crucial role in the battery's lifespan and safety. As the performance of single batteries continues to improve, the requirements for their sealing performance are also becoming increasingly stringent.

[0003] However, the current terminal sealing structure of secondary batteries on the market has poor sealing performance, which can easily lead to many safety problems, such as leakage and short circuits, thus failing to meet the sealing requirements of high-performance secondary batteries. Utility Model Content

[0004] This invention provides a secondary battery, a battery pack, and an electronic device to improve the sealing performance of the secondary battery.

[0005] This utility model provides a secondary battery, which includes: a shell, an electrode assembly, a terminal post, a first insulating member, and at least one sealing layer; the shell includes an end wall and a side wall surrounding the end wall, and the end wall is provided with a terminal post hole; the electrode assembly is disposed inside the shell; the terminal post is fixed to the end wall and electrically connected to the electrode assembly, the terminal post includes a columnar portion and a first limiting portion, the columnar portion penetrates through the terminal post hole, the first limiting portion is located inside the shell and extends from the columnar portion to the outer periphery of the end wall; the first insulating member surrounds the columnar portion and is at least partially clamped between the first limiting portion and the end wall; at least one sealing layer is disposed around the columnar portion; the sealing layer is located between the end wall and the first insulating member, and / or between the first limiting portion and the first insulating member; the projection of the sealing layer in the thickness direction falls entirely into the end wall, and the projections of the first insulating member, the sealing layer, the first limiting portion, and the end wall in the thickness direction of the end wall at least partially overlap each other, and the sealing layer is an elastically compressible sealant layer.

[0006] In one embodiment of this utility model, the thickness of the sealing layer is h, where 0.1mm≤h≤1mm.

[0007] In one embodiment of the present invention, a sealing layer is disposed on the end wall, and / or, a sealing layer is disposed on the first insulating member, and / or, a sealing layer is disposed on the first limiting portion, and / or, the secondary battery further includes a sealing member, the electrode post further includes a second limiting portion, the second limiting portion is located outside the housing and extends from the columnar portion to the outer periphery of the end wall, the sealing member is disposed around the columnar portion and is located between the second limiting portion and the end wall.

[0008] In one embodiment of the present invention, the first limiting part is a riveted flange structure, and the first insulating member is squeezed by the first limiting part to form a first receiving part that accommodates the first limiting part.

[0009] In one embodiment of the present invention, the first limiting portion is pressed against the sealing layer, and the sealing layer is disposed on the surface of the first insulating member facing the first limiting portion, such that the sealing layer forms a second receiving portion for accommodating the first limiting portion; or, the first limiting portion is pressed against the first insulating member.

[0010] In one embodiment of the present invention, the first insulating member includes grooves disposed on one or both sides in its thickness direction, the sealing layer is compressed and filled in the grooves of the first insulating member facing the end wall, and / or, the sealing layer at least partially fills the grooves of the first insulating member facing away from the end wall.

[0011] In one embodiment of the present invention, the secondary battery further includes a second insulating member, at least a portion of which surrounds the first insulating member. The first and second insulating members overlap to electrically isolate the electrode assembly from the end wall. The sealing layer is formed by fully spraying the first insulating member.

[0012] In one embodiment of this utility model, the sealant is one of epoxy-based sealant, silicone sealant, or single / two-component polyurethane.

[0013] This utility model also provides a battery pack, which includes any of the above-mentioned secondary batteries.

[0014] This invention also provides an electronic device that includes the aforementioned battery pack.

[0015] The beneficial effects of this utility model are as follows: This utility model proposes a secondary battery in which a sealing layer is provided between the end wall and the first insulating member and / or between the first limiting part and the first insulating member, and the projections of the first insulating member, the sealing layer, the first limiting part, and the end wall in the thickness direction of the end wall at least partially overlap. Specifically, at least one sealing layer is provided in the area where the first limiting part of the electrode post is clamped between the end wall and the first limiting part. Under the clamping action of the first limiting part and the end wall, the sealing layer increases the sealing area. Furthermore, since the sealing layer is an elastically compressible sealant layer, it possesses resilience, which can compensate for the gap generated between the end wall and the first limiting part when the casing deforms. This achieves a seal between the end wall and the electrode post, thereby improving the sealing effect between the end wall and the electrode post and mitigating the problem of easy seal failure. Attached Figure Description

[0016] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application. It is obvious that the drawings described below are merely some embodiments of this application, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort.

[0017] In the attached diagram:

[0018] Figure 1 This is a schematic diagram of the structure of a secondary battery provided in an embodiment of the present invention;

[0019] Figure 2 This is a schematic diagram of the structure of the electrode assembly in a secondary battery provided in one embodiment of the present invention;

[0020] Figure 3 for Figure 1 A magnified view of a section at point A in the middle;

[0021] Figure 4 for Figure 3 A magnified view of a section at point B in the middle;

[0022] Figure 5 for Figure 4 A magnified view of a section at point C;

[0023] Figure 6 for Figure 3 A partially enlarged view of another embodiment at point B;

[0024] Figure 7 for Figure 6 A magnified view of a section at point D;

[0025] Figure 8 for Figure 3 A partial enlarged view of another embodiment at point B;

[0026] Figure 9 for Figure 1 A partially enlarged view of another embodiment at point A;

[0027] Figure 10 for Figure 9 A magnified view of a section at point E in the middle;

[0028] Figure 11 for Figure 10 A magnified view of part of F;

[0029] Figure 12 for Figure 1 A partial enlarged view of another embodiment at point A in the middle;

[0030] Figure 13 for Figure 12 A magnified view of a section at point G in the middle;

[0031] Figure 14 This is a schematic diagram of the structure of a battery pack provided in an embodiment of the present invention;

[0032] Figure 15 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present invention.

[0033] The attached figures are labeled as follows:

[0034] 1. Electronic device; 10. Battery pack; 11. Working part; 101. Housing; 102. Housing cover; 100. Secondary battery; 110. Casing; 111. End wall; 1111. Terminal hole; 112. Side wall; 113. Opening; 120. Electrode assembly; 121. Positive electrode; 1211. Positive current collector; 1212. First coated area; 1213. First uncoated area; 122. Separator; 123. Negative electrode; 1231. Negative current collector; 123 2. Second coated area; 123. Second uncoated area; 124. Negative electrode tab; 125. Positive electrode tab; 130. Cover plate; 140. Electrode post; 141. First limiting part; 142. Columnar part; 143. Second limiting part; 150. First insulating element; 151. First insulating part; 152. Second insulating part; 153. Groove; 154. First receiving part; 160. Sealing element; 170. Sealing layer; 171. Second receiving part; 180. Second insulating element. Detailed Implementation

[0035] The following specific examples illustrate the implementation of this utility model. Those skilled in the art can easily understand other advantages and effects of this utility model from the content disclosed in this specification. This utility model can also be implemented or applied through other different specific embodiments. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this utility model. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0036] It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. The drawings only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components. In actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0037] In the following description, numerous details are explored to provide a more thorough explanation of embodiments of the present invention. However, it will be apparent to those skilled in the art that embodiments of the present invention may be practiced without these specific details. In other embodiments, well-known structures and devices are shown in block diagram form rather than in detail to avoid obscuring embodiments of the present invention.

[0038] Please see Figures 1 to 10This utility model provides a secondary battery 100, a battery pack 10, and an electronic device 1. The secondary battery 100 includes a housing 110, an electrode assembly 120, a terminal post 140, a first insulating member 150, and a cover plate 130. The secondary battery 100 has a sealing layer 170 between the end wall 111 of the housing 110 and the first insulating member 150 and / or between the first limiting portion 141 of the terminal post 140 and the first insulating member 150. The projections of the first insulating member 150, the sealing layer 170, the first limiting portion 141, and the end wall 111 in the thickness direction of the end wall 111 at least partially overlap each other, and the projection of the sealing layer 170 in the thickness direction falls entirely within the end wall 111. At least one sealing layer 170 is provided in the area where the first limiting part 141 of the pole post 140 is clamped with the end wall 111. Since the sealing layer 170 itself has elasticity, it can make up for the gap generated between the end wall 111 and the first limiting part 141 when the housing 110 is deformed, thereby improving the sealing effect between the end wall 111 and the pole post 140 and improving the problem of easy sealing failure. It avoids the problem that the end wall 111 is easily warped outward when the housing 110 is deformed, which weakens or even causes the sealing performance of the seal 160 to fail.

[0039] Please see Figure 1 The housing 110 includes an end wall 111 and a side wall 112 surrounding the end wall 111. As long as a stable sealing and electrical connection can be formed, the connection between the end wall 111 and the side wall 112 can be achieved in various ways, such as integral stamping, integral casting, or separate welding. The circumference of the side wall 112 is not limited; it can be cylindrical or prismatic, or it can follow any other closed-loop contour that matches the end wall 111. In this embodiment, the outer edge of the end wall 111 is circular, and the side wall 112 is cylindrical, surrounding the outer edge of the end wall 111, with a circular opening 113 formed at the end of the side wall 112 facing away from the end wall 111. A receiving cavity is formed within the housing 110 formed by the end wall 111 and the side wall 112 to accommodate the electrode assembly 120, electrolyte, and other necessary battery components. Specifically, the diameter of the housing 110 can be determined according to the specific size of the electrode assembly 120, such as 18mm, 21mm, or 46mm. The shell 110 can be made of various materials, such as copper, iron, aluminum, steel, aluminum alloy, etc. In order to prevent the shell 110 from rusting during long-term use, a layer of anti-rust material such as metallic nickel can be plated on the surface of the shell 110.

[0040] Please see Figure 1 and Figure 2The electrode assembly 120 is disposed inside the housing 110 and is a component in the secondary battery 100 where electrochemical reactions occur. The housing 110 may contain one or more electrode assemblies 120. The electrode assembly 120 includes an electrode sheet and a separator 122, which are wound to form a wound structure. Specifically, in this embodiment, the electrode assembly 120 includes a positive electrode sheet 121, a separator 122, and a negative electrode sheet 123 wound axially around the housing 110.

[0041] The positive electrode 121 includes a positive current collector 1211 and a positive active material layer coated on the positive current collector 1211. A first coated area 1212 coated with the positive active material layer and a first uncoated area 1213 uncoated with the positive active material layer are formed on the positive current collector 1211. The first coated area 1212 and the first uncoated area 1213 are arranged along the axial direction of the housing 110. The first uncoated area 1213 extends to one end of the secondary battery 100 in the height direction to the outside of the separator 122 and is bent towards the axis of the housing 110 to form a stacked positive electrode tab 125.

[0042] The negative electrode 123 includes a negative current collector 1231 and a negative active material layer coated on the negative current collector 1231. A second coated area 1232 coated with the negative active material layer and a second uncoated area 1233 uncoated with the negative active material layer are formed on the negative current collector 1231. The second coated area 1232 and the second uncoated area 1233 are arranged along the axial direction of the housing 110. The second uncoated area 1233 extends to the other end of the secondary battery 100 in the height direction to the outside of the separator 122 and is bent towards the axis of the housing 110 to form a stacked negative electrode tab 124.

[0043] A separator 122 is disposed between the positive electrode 121 and the negative electrode 123 to isolate the positive and negative active material layers. Taking a lithium-ion secondary battery 100 as an example, the positive current collector 1211 can be made of aluminum, and the positive active material layer includes positive active material, which can be lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide, etc. The negative current collector 1231 can be made of copper, and the negative active material layer includes negative active material, which can be carbon or silicon, etc. The substrate material of the separator 122 can be polypropylene (PP) or polyethylene (PE), etc. To protect and insulate the battery cell, an insulating film can also be wrapped around the outside of the battery cell. The insulating film can be synthesized from PP, PE, polyethylene terephthalate (PET), polyvinyl chloride (PVC), or other polymer materials.

[0044] Please see Figure 1 and Figure 2 Furthermore, in this invention, the positive electrode tab 125 faces the end wall 111 or the opening 113, while the negative electrode tab 124 faces the other end of the housing 110. In this embodiment, the positive electrode tab 125 faces the end wall 111 and is electrically connected to the terminal post 140, making the terminal post 140 positively charged. The negative electrode tab 124 faces the opening 113, and the housing 110 is electrically connected to the negative electrode tab 124, thus becoming negatively charged. However, in another embodiment, the negative electrode tab 124 can be connected to the terminal post 140, and the positive electrode tab 125 can be connected to the housing 110.

[0045] Please see Figure 1 The cover plate 130 is sealed and installed on the opening 113. The outer edge shape of the cover plate 130 corresponds to the shape of the opening 113 and is connected to the side wall 112 to seal the opening 113. The installation method of the cover plate 130 includes, but is not limited to, mechanical sealing or welding sealing. In this embodiment, the cover plate 130 is sealed and plugged on the opening 113 by means of mechanical sealing.

[0046] Please see Figures 1 to 3 The end wall 111 is provided with a pole post hole 1111, and the pole post 140 is installed through the pole post hole 1111 and is insulated from the end wall 111. The end of the pole post 140 facing the electrode assembly 120 passes through the end wall 111 and is directly electrically connected to the positive electrode tab 125 or indirectly connected via a transfer connection. The structure of the pole post 140 can be any suitable form that can pass through the end wall 111 and be electrically connected to the positive electrode tab 125 of the electrode assembly 120. For example, the cross-section can be circular, square, prismatic, or an irregular contour that can achieve stable conductivity. The shape of the pole post hole 1111 corresponds to the shape of the pole post 140. In this embodiment, the cross-section of the pole post 140 is circular.

[0047] Please see Figure 3 and Figure 4 The pole post 140 includes a columnar portion 142, a first limiting portion 141, and a second limiting portion 143. The columnar portion 142 passes through the pole post hole 1111. The cross-section of the columnar portion 142 can be circular, square, prismatic, or other irregular contours that can achieve stable conductivity. Considering better sealing and fitting effects, preferably, the columnar portion 142 is adapted to the pole post hole 1111, that is, the shape of the pole post hole 1111 corresponds to that of the columnar portion 142. In this embodiment, the cross-section of the columnar portion 142 is circular. The circular design facilitates processing, assembly, and sealing.

[0048] Please see Figure 3 and Figure 4In order to achieve a seal between the pole post 140 and the end wall 111, a sealing member 160 surrounding the columnar part 142 is sandwiched between the second limiting part 143 and the end wall 111. Specifically, the sealing member 160 surrounds the columnar part 142 and is pressed between the second limiting part 143 and the end wall 111. The sealing member 160 is made of an elastic material, such as EPDM rubber, fluorosilicone rubber, or fluororubber, but is not limited to these materials.

[0049] Please see Figure 3 and Figure 4 The first limiting part 141 is located inside the housing 110 and extends from the columnar part 142 toward the periphery of the end wall 111. Specifically, the first limiting part 141 connects to one end of the columnar part 142 located inside the housing 110 and extends along the side of the end wall 111 facing the inside of the housing 110 toward the outer edge of the end wall 111. The cross-section of the first limiting part 141 can be circular, square, prismatic, or other irregular contours that can achieve stable conductivity, and there is no limitation thereto. The second limiting part 143 connects to one end of the columnar part 142 located outside the housing 110 and extends along the side of the end wall 111 facing the outside of the housing 110 toward the outer edge of the end wall 111. The cross-section of the second limiting part 143 can be circular, square, prismatic, or other irregular contours that can achieve stable conductivity, and there is no limitation thereto.

[0050] Please see Figure 3 and Figure 4 It should be noted that the electrode post 140 is fixed to the end wall 111 by the first limiting part 141 and the second limiting part 143. In this embodiment, the electrode post 140 is riveted. Specifically, the first limiting part 141 can be formed by riveting, the second limiting part 143 can also be formed by riveting, or both the first limiting part 141 and the second limiting part 143 can be formed by riveting. In one example, the first limiting part 141 in this embodiment is the riveting part. Since the first limiting part 141, as the riveting part, is formed by riveting later, while the second limiting part 143 is processed before riveting, the electrode post 140 is made of a conductive metal material. The material of the electrode post 140 can be copper, nickel, or aluminum, etc. In this embodiment, the material of the electrode post 140 is aluminum, and choosing aluminum makes it easy to perform the riveting process.

[0051] Of course, in other embodiments, the pole post 140 may not include the second limiting part 143 described in the above embodiments, but only include the interconnected columnar part 142 and the first limiting part 141. In this case, the pole post 140 and the end wall 111 can be fixed by an insulated threaded connection between the columnar part 142 and the pole post hole 1111. For example, an insulating sleeve with a threaded hole is pre-fixed in the pole post hole 1111; at the same time, an external thread is machined on the outer surface of the columnar part 142. During assembly, the columnar part 142 is screwed into the threaded hole of the insulating sleeve, and the pole post 140 and the insulating sleeve are fixedly connected by thread fastening, thereby completing the fixed installation of the pole post 140 and the end wall 111.

[0052] Please see Figure 3 and Figure 4 The first insulating member 150 surrounds the columnar portion 142 and is at least partially sandwiched between the first limiting portion 141 and the end wall 111, located on the side of the end wall 111 facing the interior of the housing 110 and isolating the electrode assembly 120 from the end wall 111. The shape and size of the first insulating member 150 are not limited, and the cross-section of the first insulating member 150 can be circular, square, polygonal or other irregular shapes.

[0053] Considering that when gas is generated inside the secondary battery 100 and the internal pressure becomes too high, the end wall 111 is prone to warping outward, the sealing performance of the seal 160 is weakened, and a gap appears between the end wall 111 and the first insulating member 150. Therefore, please refer to... Figures 3 to 13 In one embodiment of this utility model, at least one sealing layer 170 is provided, which surrounds the columnar portion 142. The sealing layer 170 is located between the end wall 111 and the first insulating member 150, and / or between the first limiting portion 141 and the first insulating member 150; to achieve a circumferential all-round seal on the pole post 140, preventing leakage points and reducing the sealing effect. The sealing layer 170 can be a circular ring, a square ring, a polygonal ring, or other irregular shapes, and is not limited thereto, as long as it can achieve a closed surround of the columnar portion 142. The sealing layer 170 is an elastically compressible sealant layer. When the end wall 111 is tilted outward, the sealing layer 170 has resilience, which can compensate for the gap between the end wall 111 and the first insulating member 150, thereby reducing the probability of seal failure.

[0054] It is understood that, in one embodiment, please refer to Figures 4 to 5 The sealing layer 170 is disposed between the first limiting portion 141 and the first insulating member 150; in another embodiment, please refer to Figures 6 to 7 The sealing layer 170 is disposed between the end wall 111 and the first insulating member 150; in another embodiment, please refer to Figures 8 to 9A sealing layer 170 is provided between the end wall 111 and the first insulating member 150, and between the first limiting part 141 and the first insulating member 150. The sealing layer 170 is provided at both locations, which can be applied separately or by coating the first insulating member 150 as a whole. This arrangement is beneficial to improving processing efficiency and processing quality.

[0055] Please see Figure 6 and Figure 8 The projections of the first insulating member 150, the sealing layer 170, the first limiting part 141, and the end wall 111 in the thickness direction of the end wall 111 at least partially overlap. This arrangement allows the sealing layer 170 to be at least partially clamped by the first limiting part 141 and the end wall 111, either directly or indirectly. It can be understood that although the sealing layer 170 located between the first insulating member 150 and the end wall 111 is not in direct contact with the first limiting part 141, it is indirectly subjected to the clamping force of the first limiting part 141, thus having the same clamping effect. Under the clamping action of the first limiting part 141 and the end wall 111, the sealing layer 170 can achieve auxiliary sealing between the end wall 111 and the pole post 140, thereby improving the sealing effect between the end wall 111 and the pole post 140 and mitigating the problem of easy sealing failure.

[0056] Furthermore, the sealing layer 170 is an elastically compressible sealant layer. The material and forming process of the sealing layer 170 are not limited; please refer to [link / reference]. Figures 3 to 13 In one embodiment of this utility model, the material and forming process of the sealing layer 170 are not limited. For example, it can be achieved by coating with an elastic sealant, such as epoxy-based sealant, silicone sealant, single / two-component polyurethane, etc., without limitation. The above-mentioned sealants all have high resilience and chemical stability, which is beneficial to achieving better sealing performance in the secondary battery 100. The elastically compressible sealant has resilience and can compensate for the gap that appears between the end wall 111 and the first insulating member 150, thereby reducing the probability of seal failure.

[0057] Please see Figure 4 and Figure 5 In one embodiment of this utility model, the thickness of the sealing layer 170 is h, where 0.1mm ≤ h ≤ 1mm. If h is less than 0.1mm, the elastic recovery will be limited, resulting in insufficient sealing performance; if h is greater than 1mm, the sealing layer 170 will be too thick, and an excessively thick adhesive layer will have greater internal stress and be easily damaged under pressure, thus compromising the sealing performance. Therefore, limiting the thickness to 0.1mm ≤ h ≤ 1mm allows the sealing layer 170 to have better resilience and higher stability, thereby achieving better sealing performance.

[0058] Please see Figure 5 and Figure 7In one embodiment of the present invention, the first limiting part 141 is a riveted flange structure. The first limiting part 141 is pressed onto the sealing layer 170 or the first insulating member 150, so that the sealing layer 170 forms a second receiving part 171 to accommodate the first limiting part 141, and the first insulating member 150 forms a first receiving part 154 to accommodate the first limiting part 141.

[0059] In one embodiment, please refer to Figure 7 No sealing layer 170 is provided on the side of the first insulating member 150 facing the first limiting portion 141. The riveting flange structure can be pressed inward onto the first insulating member 150. The first insulating member undergoes plastic deformation under the pressing pressure. A first receiving portion 154 is formed on the first insulating member 150 to accommodate the first limiting portion 141. It can be understood that accommodating the first limiting portion 141 does not mean accommodating the entire first limiting portion 141, but rather accommodating the pressing position of the first limiting portion 141. This arrangement increases the clamping force between the first limiting portion 141 and the end wall 111, thereby improving the sealing performance. In this embodiment, the first limiting portion 141 has a large clamping and riveting force, causing the first insulating member 150 to undergo extrusion deformation, thus improving the sealing performance.

[0060] In another embodiment, please refer to Figure 4 and Figure 5 A sealing layer 170 is provided on the side of the first insulating member 150 facing the first limiting portion 141. The riveting flange structure can be pressed inward to the sealing layer 170, forming a second receiving portion 171 on the sealing layer 170. At the same time, a first receiving portion 154 is formed on the first insulating member 150. It can be understood that the riveting flange structure can be pressed inward to the sealing layer 170. Due to the large riveting force, the surface of the sealing layer 170 is deformed by the first limiting portion 141 to form the second receiving portion 171. The surface of the first insulating member 150 is deformed by the first limiting portion 141 and the sealing layer 170 together to form the first receiving portion 154. This increases the sealing surface of the first limiting portion 141 and the sealing layer 170, and also increases the clamping force between the first limiting portion 141 and the end wall 111, thereby improving the sealing performance.

[0061] Please see Figure 9 and Figure 10In one embodiment of this utility model, the first insulating member 150 includes a groove 153 disposed on one or both sides of its thickness direction. The groove 153 surrounds the pole post 140. For example, in one embodiment, a groove 153 is disposed on one side of the first insulating member 150; in other embodiments, grooves 153 are disposed on both sides of the first insulating member 150. The groove 153 can increase the thickness of the sealing layer 170, further improve the compression ratio of the sealing layer 170, and thus improve the resilience of the sealing layer 170. Of course, in other embodiments of this utility model, the surfaces on both sides of the first insulating member 150 may not have grooves 153, that is, the surfaces of the first insulating member 150 facing the end wall 111 are entirely flat, and the sealing layer 170 can be directly formed on this flat surface by coating or spraying processes, such as... Figure 3 As shown.

[0062] Please see Figure 9 and Figure 10 Furthermore, the sealing layer 170 is compressed and filled in the groove 153 of the first insulating member 150 facing the end wall 111, and / or, the sealing layer 170 at least partially fills the groove 153 of the first insulating member 150 facing away from the end wall 111. It can be understood that when the groove 153 is provided on the side of the first insulating member 150 facing the end wall 111, the sealing layer 170 is compressed and filled in the groove 153. That is, before the pole post 140 is riveted, the sealing layer 170 protrudes from the groove 153. Under the clamping action after the pole post 140 is riveted, the sealing layer 170 is compressed and filled in the groove 153. This arrangement ensures that the sealing layer 170 has a large rebound force. When the end wall 111 tilts outward and there is a gap between it and the first insulating member 150, the sealing layer 170 will rebound to fill the gap, thereby improving the problem of sealing failure. When the first insulating member 150 has a groove 153 on the side facing away from the end wall 111, the sealing layer 170 is at least partially pressed by the first limiting part 141, thus achieving a first sealing performance. The sealing performance is improved by the rebound force. Furthermore, the sealing surfaces of the first limiting part 141 and the sealing layer 170 are increased. Therefore, the sealing layer 170 can at least partially fill the groove 153 of the first insulating member 150 facing away from the end wall 111. That is, the sealing layer 170 can protrude from the groove 153 or not, and there is no limitation on this.

[0063] Please see Figure 10 and Figure 11In one embodiment of this utility model, a groove 153 is provided on the side of the first insulating member 150 facing the electrode assembly 120, and the sealing layer 170 at least partially fills the groove 153 of the first insulating member 150 facing the electrode assembly 120. At this time, because the sealing layer 170 has a relatively thick thickness, the riveting flange structure of the first limiting portion 141 is only internally pressed into the sealing layer 170, forming a first receiving portion 154 in the sealing layer 170. This arrangement improves the sealing performance while also alleviating... Figure 11 The technical problem is that the end of the first insulating member 150 away from the pole post 140 is tilted towards the electrode assembly 120.

[0064] Please see Figure 4 and Figure 6 In one embodiment of the present invention, the first insulating member 150 includes a first insulating portion 151 and a second insulating portion 152 connected to each other. The first insulating portion 151 is located between the columnar portion 142 and the pole hole 1111, and the second insulating portion 152 is located between the first limiting portion 141 and the end wall 111. At least one sealing layer 170 is located between the end wall 111 and the second insulating portion 152, and / or, at least one sealing layer 170 is located between the first limiting portion 141 and the second insulating portion 152.

[0065] Please see Figure 8 and Figure 13 To improve the sealing performance between the columnar portion 142 and the pole post hole 1111, at least one additional sealing layer 170 is provided between the columnar portion 142 and the pole post hole 1111. The sealing layer 170 is located between the columnar portion 142 and the first insulating portion 151, and / or, at least one additional sealing layer 170 is located between the first insulating portion 151 and the pole post hole 1111. The sealing layers 170 at each of the above locations can effectively fill the gap between the pole post 140 and the pole post hole 1111, thereby improving the sealing performance between the pole post 140 and the pole post hole 1111. Multiple sealing layers 170 are arranged around the columnar portion 142 to achieve omnidirectional sealing of the pole post 140, preventing leakage points and reducing the sealing effect. It should be noted that the multiple additional sealing layers 170 located at different positions can be formed individually or integrally. Furthermore, in one embodiment, the sealing layer 170 located between the end wall 111 and the first limiting portion 141 and another sealing layer 170 located between the pole post 140 and the pole post hole are formed separately. In another embodiment, the sealing layer 170 and the other sealing layer 170 are integrally formed, such as... Figure 8 and Figure 13 As shown.

[0066] Please see Figure 8In one embodiment of this utility model, the sealing layer 170 is disposed on the first insulating portion 151, and / or, the sealing layer 170 is disposed on the inner sidewall 112 of the electrode hole 1111, and / or, the sealing layer 170 is disposed on the surface of the electrode 140. The material and forming process of the sealing layer 170 are not limited. For example, it can be achieved by coating the surface of the first insulating portion 151, the inner sidewall 112 of the electrode hole 1111, and the surface of the columnar portion 142 of the electrode 140 with various elastic lithium-ion sealants; this is not limited.

[0067] Please see Figure 7 and Figure 8 In one embodiment of this utility model, the secondary battery 100 further includes a second insulating member 180, at least a portion of which surrounds the first insulating member 150. The first insulating member 150 and the second insulating member 180 overlap to electrically isolate the electrode assembly 120 from the end wall 111. The sealing layer 170 is formed by fully spraying the first insulating member 150. While ensuring insulation performance, fully spraying the first insulating member 150 reduces the process difficulty; compared to... Figure 3 As shown, the first insulating component 150 is fully sprayed, which reduces the amount of spraying material used.

[0068] Please see Figure 14 and Figure 15 In one embodiment of this utility model, the first insulating member 150 surrounds the columnar portion 142. Specifically, the first insulating member 150 is provided with a through hole through which the columnar portion 142 passes. The external shape and size of the first insulating member 150 are not limited. For example, the external shape of the first insulating member 150 can be circular, polygonal, or other shapes. Further, the first insulating member 150 is at least partially clamped between the first limiting portion 141 and the end wall 111. This can be understood as at least a portion of the first insulating member 150 being located between the first limiting portion 141 and the end wall 111 to achieve insulation between the first limiting portion 141 and the end wall 111. Of course, there may also be a portion not located between the first limiting portion 141 and the end wall 111.

[0069] Please see Figure 12 and Figure 13At least a portion of the second insulating member 180 surrounds the first insulating member 150 to allow the first insulating member 150 to extend radially along the end wall 111. The shape of the second insulating member 180 is not limited and can be a circular ring, a polygonal ring, or other irregular rings. Preferably, the inner ring of the second insulating member 180 is adapted to the shape of the first insulating member 150, and the outer ring of the second insulating member 180 is adapted to the inner wall of the housing 110. In this embodiment, the second insulating member 180 is circular. The first insulating member 150 and the second insulating member 180 overlap to electrically isolate the electrode assembly 120 from the end wall 111. The overlap of the first insulating member 150 and the second insulating member 180 means that the second insulating member 180 partially overlaps with the first insulating member 150, so that there is no gap between the first insulating member 150 and the second insulating member 180. This reduces the risk of short circuits occurring between the electrode assembly 120 and the end wall 111 at the gap between the first insulating member 150 and the second insulating member 180.

[0070] Please see Figure 12 and Figure 13 By adding a second insulating component 180 that is separately configured from the first insulating component 150, firstly, the structures of the first insulating component 150 and the second insulating component 180 can be designed separately according to requirements, and different structures or materials can be selected according to different structural, insulation, and heat resistance requirements, reducing the difficulty of design and component molding and improving design flexibility. Secondly, compared to Figure 3 In the illustrated embodiment, without the second insulating member 180, the radial dimension of the first insulating member 150 is reduced, and the warping deformation is smaller. This arrangement can weaken the clamping force acting on the first insulating member 150 on the end of the second insulating member 180 away from the pole post 140, thus improving... Figure 3 The technical problem is that the end of the first insulating member 150 away from the electrode post 140 is tilted towards the electrode assembly 120. Thirdly, since the first limiting portion 141 is pressed against the first insulating member 150, the sealing layer 170 can be disposed on the first insulating member 150 to improve sealing performance. For example, in one embodiment, the sealing layer 170 can be formed by coating the entire first insulating member 150 with sealant only. Under the clamping force of the first limiting portion 141 and the end wall 111, the sealing layer 170 can assist in sealing, improving battery life. Furthermore, the overall full coating process reduces processing difficulty and lowers costs.

[0071] Please see Figure 14This utility model also provides a battery pack 10, which includes the secondary battery 100 described above. In one embodiment of the battery pack 10, the battery pack 10 includes a housing 101, a cover 102, and multiple secondary batteries 100. The multiple secondary batteries 100 are placed in the housing 101 and are connected in series or parallel, or a combination of series and parallel connections. The cover 102 covers the housing 101 to protect the multiple secondary batteries 100. It should be noted that, in addition to the secondary battery 100 of this utility model, the battery pack 10 may also include a battery pack thermal management system, circuit board, etc. The battery pack 10 can be a battery module, a battery pack, an energy storage cabinet, etc.; these will not be described in detail here.

[0072] Please see Figure 15 This utility model also provides an electronic device 1, which includes the aforementioned battery pack 10. A working part 11 is electrically connected to the battery pack 10 to obtain electrical power. As an example, the electronic device 1 is a vehicle, which can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, but are not limited thereto. The working part 11 is the vehicle body, and the battery pack 10 is located at the bottom of the vehicle body, providing electrical power for the vehicle's operation or the operation of its internal electrical components. However, in other embodiments, the electronic device 1 can also be a mobile phone, portable device, laptop computer, ship, spacecraft, electric toy, and power tool, etc. Spacecraft include airplanes, rockets, space shuttles, and spacecraft, etc.; the working part 11 can be a unit component capable of obtaining electrical power from the battery pack 10 and performing corresponding work, such as a fan blade rotation unit or a vacuum cleaner suction unit. Electric toys include stationary or mobile electric toys, such as game consoles, electric car toys, electric boat toys, and electric airplane toys, etc.; power tools include metal cutting power tools, grinding power tools, assembly power tools, and railway power tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers, etc. This application does not impose any special limitations on the aforementioned electronic device 1.

[0073] This utility model proposes a secondary battery in which a sealing layer is provided between the end wall and the first insulating member and / or between the first limiting part and the first insulating member, and the projections of the first insulating member, the sealing layer, the first limiting part, and the end wall in the thickness direction of the end wall at least partially overlap each other. That is, by providing at least one sealing layer in the area where the first limiting part of the electrode is clamped between the end post and the end wall, auxiliary sealing can be achieved between the end wall and the electrode post, thereby improving the sealing effect between the end wall and the electrode post and mitigating the problem of easy sealing failure.

[0074] The above embodiments are merely illustrative of the principles and effects of this utility model and are not intended to limit the scope of this utility model. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of this utility model. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in this utility model should still be covered by the claims of this utility model.

Claims

1. A secondary battery, characterized in that, include: The housing includes an end wall and a side wall surrounding the end wall, the end wall being provided with a pole post hole; Electrode assemblies are disposed inside the housing; An electrode post is fixed to the end wall and electrically connected to the electrode assembly. The electrode post includes a columnar portion and a first limiting portion. The columnar portion passes through the electrode post hole, and the first limiting portion is located inside the housing and extends from the columnar portion to the outer periphery of the end wall. A first insulating element surrounds the columnar portion and is at least partially clamped between the first limiting portion and the end wall; At least one sealing layer is disposed around the columnar portion; the sealing layer is located between the end wall and the first insulating member, and / or between the first limiting portion and the first insulating member; Wherein, the projection of the sealing layer in the thickness direction falls entirely into the end wall, and the projections of the first insulating member, the sealing layer, the first limiting part, and the end wall in the thickness direction of the end wall at least partially overlap each other, and the sealing layer is an elastically compressible sealant layer.

2. The secondary battery according to claim 1, characterized in that, The thickness of the sealing layer is h, where 0.1mm ≤ h ≤ 1mm.

3. The secondary battery according to claim 1, characterized in that, The sealing layer is disposed on the end wall, and / or, the sealing layer is disposed on the first insulating member, and / or, the sealing layer is disposed on the first limiting portion, and / or... The secondary battery also includes a sealing element, and the electrode post also includes a second limiting portion. The second limiting portion is located outside the housing and extends from the columnar portion to the outer periphery of the end wall. The sealing element is disposed around the columnar portion and is located between the second limiting portion and the end wall.

4. The secondary battery according to claim 1, characterized in that, The first limiting part is a riveted flange structure, and the first insulating part is formed by the compression of the first limiting part to accommodate the first limiting part.

5. The secondary battery according to claim 4, characterized in that, The first limiting portion is pressed against the sealing layer, and the sealing layer is disposed on the surface of the first insulating member facing the first limiting portion, such that the sealing layer forms a second receiving portion that accommodates the first limiting portion; or, the first limiting portion is pressed against the first insulating member.

6. The secondary battery according to any one of claims 1 to 3, characterized in that, The first insulating member includes grooves disposed on one or both sides in its thickness direction, the sealing layer is compressed and filled in the grooves of the first insulating member facing the end wall, and / or, the sealing layer at least partially fills the grooves of the first insulating member facing away from the end wall.

7. The secondary battery according to claim 1, characterized in that, The secondary battery further includes a second insulating member, at least a portion of which surrounds the first insulating member. The first and second insulating members overlap to electrically isolate the electrode assembly from the end wall. The sealing layer is formed by fully spraying the first insulating member.

8. The secondary battery according to claim 1, characterized in that, The sealant is one of epoxy-based sealant, silicone sealant, or single / two-component polyurethane.

9. A battery pack, characterized in that, The secondary battery includes any one of claims 1 to 8.

10. An electronic device, characterized in that, Includes the battery pack as described in claim 9.

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