Secondary battery and battery pack

Abstract

Provided in the present disclosure are a secondary battery and a battery pack. The secondary battery comprises a casing, an electrode assembly and a cover plate assembly. The casing is provided with an accommodating cavity; the electrode assembly comprises a body and tabs; the cover plate assembly comprises a cover plate, a blocking member, a first insulating member, terminal posts and connecting pieces; the cover plate is connected to the casing, and the first insulating member is connected to the cover plate; the terminal posts pass through the cover plate and the first insulating member; the side of each connecting piece facing away from the electrode assembly is connected to a terminal post; the tabs are electrically connected to the connecting pieces.

Description

Secondary batteries and battery packs

[0001] This application claims priority to Chinese Utility Model Patent Application No. 202422772051.8, filed on November 13, 2024, entitled "Secondary Battery and Battery Pack", the entire contents of which are incorporated herein by reference. Technical Field

[0002] This disclosure belongs to the field of battery technology, specifically relating to a secondary battery and battery pack. Background Technology

[0003] In the field of power batteries, when connecting multiple electrode components and cover plate components, it is necessary to place multiple electrode components on both sides of the cover plate component, connect the cover plate component and the electrode components' tabs, and then flip and merge the multiple electrode components before placing them into the housing.

[0004] However, connecting multiple electrode assemblies and cover plate assemblies requires a large operating space to position the multiple electrode assemblies on both sides of the cover plate. The difficulty in flipping and merging the electrode assemblies results in high manufacturing difficulty and low manufacturing efficiency for the secondary battery. Summary of the Invention

[0005] This disclosure provides a secondary battery to solve the technical problems of high manufacturing difficulty and low manufacturing efficiency of secondary batteries; another objective of this disclosure is to provide a battery pack.

[0006] The present disclosure provides a secondary battery having intersecting thickness and length directions, comprising: a housing having a receiving cavity; an electrode assembly disposed in the receiving cavity, the electrode assembly including a body and tabs connected to each other; a cover plate assembly including a cover plate, a sealing member, a first insulating member, a terminal post, and a connecting piece; the cover plate is connected to the housing and seals the receiving cavity, the cover plate having an operating opening extending through the cover plate along the thickness direction, the operating opening communicating with the receiving cavity; the sealing member is connected to the cover plate and seals the operating opening; the first insulating member is disposed in the receiving cavity and connected along the thickness direction to the cover plate facing the electrode. One side of the assembly; the electrode post passes through the cover plate and the first insulating member, the electrode post and the sealing member are spaced apart along the length direction; the connecting piece is disposed in the receiving cavity, and the side of the connecting piece away from the electrode assembly is connected to the electrode post, the electrode tab is electrically connected to the connecting piece, and at least a portion of the electrode tab and the connecting piece on the cover plate along the thickness direction is exposed above the operating port; the second insulating member is disposed in the receiving cavity and connected to the first insulating member, and along the thickness direction, the second insulating member is connected to the side of the body facing the cover plate, and the side of the connecting piece away from the cover plate is connected to the second insulating member.

[0007] In some embodiments, the second insulating member includes a base and a support portion. The base is connected to the side of the connecting piece facing the body along the thickness direction. The support portion is connected between the base and the body along the thickness direction and connects the base and the body respectively. The tab and the support portion are spaced apart along the length direction.

[0008] In some embodiments, the pole is inserted through the first insulating member, the first insulating member having a second mounting hole communicating with the operating port and the receiving cavity; the second insulating member further includes a connecting portion connected to the first insulating member, a portion of the connecting portion being connected to the base along the thickness direction.

[0009] In some embodiments, the base has a first connection hole extending through the base along the thickness direction, a portion of the tab passes through the first connection hole and is connected to the side of the connecting piece opposite to the electrode assembly.

[0010] In some embodiments, the connecting piece has a second connecting hole extending through the connecting piece along the thickness direction, the second connecting hole communicating with the first connecting hole, and the electrode tab passing through the first connecting hole passing through the second connecting hole.

[0011] In some embodiments, the sealing member has a first surface facing the receiving cavity, and along the thickness direction, the orthographic projection of the connecting piece onto the plane containing the first surface lies within the orthographic projection of the base onto the plane containing the first surface.

[0012] In some embodiments, the sealing member further has an injection hole extending through the sealing member along the thickness direction; the base has a diversion region, the diversion region has a diversion cavity opening towards the injection hole, the diversion cavity communicating with the injection hole; the diversion region is provided with a first diversion hole extending through the thickness direction, the first diversion hole communicating with the diversion cavity and the receiving cavity; the first diversion hole has a first hole wall, the first hole wall being located on the periphery of the injection hole in the orthographic projection of the sealing member along the thickness direction.

[0013] In some embodiments, the second insulating member is further provided with a diversion groove, the diversion groove penetrating the base and the surface of the support portion facing the base along the thickness direction, and the support portion is provided with a second diversion hole penetrating along the thickness direction, the second diversion hole communicating with the diversion groove.

[0014] In some embodiments, the cover plate assembly includes a plurality of connecting tabs; the second insulating member further includes a protrusion connected to a side of the base along the thickness direction near the connecting tabs, and at least one of the connecting tabs connected to a side of the protrusion along the thickness direction away from the base.

[0015] This disclosure also provides a battery pack including a secondary battery as described in any of the above embodiments.

[0016] Beneficial Effects: The secondary battery provided in this disclosure includes a casing, an electrode assembly, and a cover assembly. The casing has a receiving cavity; the electrode assembly is disposed in the receiving cavity and includes a body and tabs connected to each other; the cover assembly includes a cover plate, a sealing member, a first insulating member, a terminal post, and a connecting piece; the cover plate is connected to the casing and seals the receiving cavity, and the cover plate has an operating opening extending through the cover plate along the thickness direction, which communicates with the receiving cavity; the sealing member is connected to the cover plate and seals the operating opening; the first insulating member is disposed in the receiving cavity and is connected along the thickness direction to the side of the cover plate facing the electrode assembly; the terminal post passes through the cover plate and the first insulating member, and the terminal post and the sealing member are spaced apart along the length direction; the connecting piece is disposed in the receiving cavity, and the side of the connecting piece away from the electrode assembly is connected to the terminal post, the tab is electrically connected to the connecting piece, and at least a portion of the tab and the connecting piece on the cover plate along the thickness direction is exposed above the operating opening; the second insulating member is disposed in the receiving cavity and is connected to the first insulating member, and along the thickness direction, the second insulating member is connected to the side of the body facing the cover plate, and the side of the connecting piece away from the cover plate is connected to the second insulating member. The cover plate in this disclosure is provided with an operation port, which allows for welding of the tabs and connecting pieces after the electrode assembly is placed into the housing. This reduces the welding difficulty of the tabs and connecting pieces and improves the manufacturing efficiency of the secondary battery.

[0017] Meanwhile, this disclosure provides a second insulating component to insulate the main body and the connecting piece, preventing the connecting piece from being inserted into the main body and causing a short circuit, thereby improving the reliability of the secondary battery. Attached Figure Description

[0018] The technical solution and other beneficial effects of this disclosure will become apparent from the following detailed description of specific embodiments in conjunction with the accompanying drawings.

[0019] Figure 1 is a schematic diagram of the structure of the secondary battery provided in an embodiment of this disclosure;

[0020] Figure 2 is a cross-sectional view of a secondary battery provided in an embodiment of this disclosure;

[0021] Figure 3 shows a detailed view of area C circled in Figure 2;

[0022] Figure 4 is a cross-sectional view of the secondary battery provided in an embodiment of this disclosure from another angle;

[0023] Figure 5 is a detailed view of area A in Figure 4;

[0024] Figure 6 shows a detailed view of section B in Figure 4;

[0025] Figure 7 is a schematic diagram of the structure of the cover plate assembly in the secondary battery provided in an embodiment of this disclosure;

[0026] Figure 8 is an exploded view of the cover plate assembly in the secondary battery provided in the embodiment of this disclosure;

[0027] Figure 9 is a bottom view of the cover plate assembly in the secondary battery provided in an embodiment of this disclosure;

[0028] Figure 10 is a schematic diagram of the structure of the first insulating component in the secondary battery provided in an embodiment of this disclosure;

[0029] Figure 11 is a schematic diagram of the structure of the second insulating component in the secondary battery provided in an embodiment of this disclosure;

[0030] Figure 12 is a front view of the second insulating component in a secondary battery provided in an embodiment of this disclosure; and

[0031] Figure 13 is a top view of the second insulating member in the secondary battery provided in an embodiment of this disclosure.

[0032] Reference numerals: 100-Housing shell, 110-Receiving cavity, 200-Cover assembly, 210-Cover, 211-Operating port, 212-Second hole wall, 213-Third hole wall, 214-Third surface, 215-Fourth surface, 220-Sealing element, 221-First surface, 222-Injection hole, 230-Electrode post, 240-Connecting piece, 241-Second connecting hole, 250-First insulating element, 251-Second... Mounting hole, 300-Electrode assembly, 310-Body, 320-Electrode tab, 400-Second insulating element, 410-Base, 411-First connecting hole, 420-Support part, 421-Second diversion hole, 430-Connecting part, 440-Diversion area, 441-Diversion cavity, 442-First diversion hole, 443-First hole wall, 444-Second surface, 445-Through groove, 450-Diversion groove, 460-Protrusion. Detailed Implementation

[0033] The technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this disclosure, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this disclosure without creative effort are within the scope of protection of this disclosure.

[0034] In the description of this disclosure, it should be noted that, unless otherwise expressly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal connection of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this disclosure according to the specific circumstances. In the description of this disclosure, "a plurality of" means two or more, unless otherwise expressly and specifically limited. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more features.

[0035] It should also be noted that in the accompanying drawings of the embodiments of this disclosure, the arrows labeled X, Y, and Z respectively represent the length direction X, the width direction Y, and the thickness direction Z. The description of this disclosure introduces the length direction X, the width direction Y, and the thickness direction Z to more clearly express the relative positional relationships involved in this disclosure. The length direction X, the width direction Y, and the thickness direction Z are three relative directions that intersect each other, rather than absolute directions. In practical applications, the length direction X, the width direction Y, and the thickness direction Z can point to any direction in space, as long as the intersection relationship between them is maintained.

[0036] The following disclosure provides many different implementations or examples for carrying out different structures of this disclosure. To simplify the disclosure, the components and arrangements of specific examples are described below. Of course, these are merely examples and are not intended to limit the scope of this disclosure.

[0037] In the field of power batteries, when connecting multiple electrode components 300 and cover plate components 200, multiple electrode components 300 need to be placed on both sides of cover plate components 200, and the tabs 320 of cover plate components 200 and electrode components 300 need to be connected. Then, multiple electrode components 300 are flipped and merged before being placed inside housing 100.

[0038] However, connecting multiple electrode assemblies 300 and cover plate assembly 200 requires a large operating space to place multiple electrode assemblies 300 on both sides of cover plate 210, and the flipping and merging of electrode assemblies 300 is difficult, resulting in high manufacturing difficulty and low manufacturing efficiency of secondary batteries.

[0039] To address the technical problems of high difficulty in flipping and merging the electrode assembly 300, resulting in high manufacturing difficulty and low manufacturing efficiency of the secondary battery, an embodiment of this disclosure provides a secondary battery. Referring to FIG1, the secondary battery includes a housing 100, an electrode assembly 300, and a cover assembly 200. The housing 100 has a receiving cavity 110. The electrode assembly 300 is disposed in the receiving cavity 110 and includes a body 310 and tabs 320 connected to each other. The cover assembly 200 includes a cover plate 210, a sealing member 220, a first insulating member 250, a terminal post 230, and a connecting piece 240. The cover plate 210 is connected to the housing 100 and seals the receiving cavity 110. The cover plate 210 has an operating opening 211 extending through the cover plate 210 along the thickness direction Z, and the operating opening 211 communicates with the receiving cavity 110. The sealing member 220 is connected to the cover plate 210 and seals the operating opening 211. A first insulating member 250 is disposed in the receiving cavity 110 and connected along the thickness direction Z to the side of the cover plate 210 facing the electrode assembly 300. An electrode post 230 passes through the cover plate 210 and the first insulating member 250, and the electrode post 230 and the sealing member 220 are spaced apart along the length direction X. A connecting piece 240 is disposed in the receiving cavity 110, and the side of the connecting piece 240 facing away from the electrode assembly 300 is connected to the electrode post 230. An electrode tab 320 is electrically connected to the connecting piece 240, and at least a portion of the electrode tab 320 and the connecting piece 240 along the thickness direction Z on the cover plate 210 exposes the operating opening 211. A second insulating member 400 is disposed in the receiving cavity 110 and connected to the first insulating member 250. Along the thickness direction Z, the second insulating member 400 is connected to the side of the body 310 facing the cover plate 210, and the side of the connecting piece 240 away from the cover plate 210 is connected to the second insulating member 400. This will be described in detail below.

[0040] In some embodiments, the battery pack includes a housing and a plurality of secondary batteries disposed within the housing. These secondary batteries include, but are not limited to, lithium-ion secondary batteries, lithium-ion primary batteries, lithium-sulfur batteries, sodium-lithium-ion batteries, sodium-ion batteries, or magnesium-ion batteries, etc., and this disclosure does not limit the specific type. The battery pack provides power to an electrical device. The electrical device can be a mobile phone, portable device, laptop computer, electric vehicle, electric car, ship, spacecraft, electric toy, or power tool, etc. For example, spacecraft include airplanes, rockets, space shuttles, and spacecraft; electric toys include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys; 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.

[0041] The secondary battery in the embodiments of this disclosure will be described below.

[0042] Referring to Figures 1 and 2, in some embodiments, the secondary battery has intersecting thickness direction Z and length direction X, and includes a housing 100, an electrode assembly 300 and a cover assembly 200, with the housing 100 having a receiving cavity 110.

[0043] The secondary battery also includes an electrode assembly 300 disposed in the receiving cavity 110, the electrode assembly 300 including a body 310 and tabs 320 connected to each other.

[0044] The secondary battery also includes a cover assembly 200, comprising a cover 210, a sealing element 220, a first insulating element 250, an electrode post 230, and a connecting piece 240. The cover 210 is connected to the housing 100 and covers the receiving cavity 110. The cover 210 has an operating opening 211 extending through the cover 210 along the thickness direction Z, and the operating opening 211 communicates with the receiving cavity 110. The sealing element 220 is connected to the cover 210 and covers the operating opening 211. The first insulating member 250 is disposed in the receiving cavity 110 and is connected to the side of the cover plate 210 facing the electrode assembly 300 along the thickness direction Z; the pole post 230 passes through the cover plate 210 and the first insulating member 250, and the pole post 230 and the sealing member 220 are spaced apart along the length direction X; the connecting piece 240 is disposed in the receiving cavity 110, and the side of the connecting piece 240 away from the electrode assembly 300 is connected to the pole post 230; the electrode tab 320 is electrically connected to the connecting piece 240; at least a portion of the electrode tab 320 and the connecting piece 240 along the thickness direction Z on the cover plate 210 is exposed at the operating port 211.

[0045] The secondary battery also includes a second insulating member 400 disposed in the receiving cavity 110 and connected to the first insulating member 250. Along the thickness direction Z, the second insulating member 400 is connected to the side of the body 310 facing the cover plate 210, and the side of the connecting piece 240 away from the cover plate 210 is connected to the second insulating member 400.

[0046] In the above embodiment, the cover plate 210 of the secondary battery is provided with an operation port 211, and at least a portion of the connecting piece 240 and the tab 320 are exposed in the operation port 211 along the thickness direction Z on the cover plate 210. In other words, along the thickness direction Z, the portion of the connecting piece 240 and the tab 320 that is projected onto the plane of the surface of the cover plate 210 facing the receiving cavity 110 is located within the operation port 211. Through this operation port 211, the tab 320 and the connecting piece 240 located inside the receiving cavity 110 can be welded, which can reduce the manufacturing difficulty of the secondary battery and improve the manufacturing efficiency of the secondary battery. Especially for the manufacturing of secondary batteries with multiple electrode assemblies 300, it can simplify the core-joining operation after the electrode assembly 300 and the cover plate assembly 200 are connected, reduce the operational difficulty in the core-joining process, and thus reduce the manufacturing difficulty of the secondary battery and improve the manufacturing efficiency.

[0047] Specifically, in this embodiment, multiple electrode components 300 are first cored together, and then the tabs 320 and connecting pieces 240 are welded together, which simplifies the core-joining process and reduces the manufacturing difficulty of secondary batteries.

[0048] Understandably, when welding the tab 320 and the connecting piece 240 through the operating port 211, since the tab 320 is located on the side of the connecting piece 240 away from the body 310, the connecting piece 240 may be subjected to a force along the thickness direction Z from the tab 320 toward the body 310. Furthermore, since only one end of the tab 320 is connected to the pole post 230, and the other end is suspended, the connecting piece 240 may deform toward the body 310 after being subjected to the force from the tab 320 toward the body 310, potentially leading to a short circuit due to contact between the connecting piece 240 and the body 310.

[0049] In the above embodiments, please refer to Figures 2 and 3 together. The secondary battery also includes a second insulating member 400, which is disposed between the connecting piece 240 and the body 310. The second insulating member 400 is connected to both the connecting piece 240 and the body 310, so that the body 310 can support the connecting piece 240 through the second insulating member 400, preventing the connecting piece 240 from deforming towards the body 310 under stress, thereby preventing short circuits caused by contact between the connecting piece 240 and the body 310. At the same time, the second insulating member 400 also insulates the connecting piece 240 and the body 310, thereby preventing the connecting piece 240 and the body 310 from being indirectly electrically connected through the second insulating member 400.

[0050] Specifically, when welding the tab 320, the connecting piece 240 is subjected to pressure from the cover plate 210 toward the electrode assembly 300. The second insulating member 400 connected between the body 310 and the connecting piece 240 can provide support for the connecting piece 240, thereby preventing the connecting piece 240 from deforming toward the body 310.

[0051] In some embodiments, referring to Figures 4, 5, 11 and 12, the second insulating member 400 includes a base 410 and a support 420. The base 410 is connected to the side of the connecting piece 240 facing the body 310 along the thickness direction Z. The support 420 is connected between the base 410 and the body 310 along the thickness direction Z, and connects the base 410 and the body 310 respectively. The tab 320 and the support 420 are spaced apart along the length direction X.

[0052] As can be understood, referring to Figure 2, a portion of the tab 320 is stacked on the side of the body 310 near the cover plate 210. The support portion 420 is used to separate the base 410 and the body 310, so that a gap is formed between the base 410 and the body 310. Simultaneously, the support portion 420 is spaced apart from the tab 320. In the above embodiment, by providing the support portion 420, the base 410 is prevented from pressing against the tab 320 when connected to the body 310 and supporting the connecting piece 240, thereby preventing damage to the tab 320 and improving the reliability of the secondary battery.

[0053] In some embodiments, referring to Figures 4 and 5, a first insulating member 250 is disposed in the receiving cavity 110 and connected to the cover plate. A pole post 230 passes through the first insulating member 250. The first insulating member 250 has a second mounting hole 251, which communicates with the operating port and the receiving cavity 110. The first insulating member 250 and the housing 100 are spaced apart and form a gap in a direction perpendicular to the thickness direction Z. The second insulating member 400 further includes a connecting portion 430, a portion of which is disposed in the gap and connected to the first insulating member 250. A portion of the connecting portion 430 is connected to the base 410 in the thickness direction Z.

[0054] In some embodiments, a snap fastener is provided on the periphery of the first insulating member 250, and a connecting hole is provided through the connecting portion 430 in a direction perpendicular to the thickness direction Z. The snap fastener can be engaged with the connecting hole so that the connecting portion 430 can be fastened to the first insulating member 250. Specifically, compared with the heat fusion connection method, the snap fastener and connecting hole method has the advantages of easy processing and low cost.

[0055] In the above embodiment, the second insulating member 400 can be fixed to the first insulating member 250, thereby facilitating the installation of the cover assembly 200 on the housing 100. Simultaneously, the first insulating member 250 can also position the second insulating member 400 along the thickness direction Z and in directions perpendicular to the thickness direction Z. Specifically, the second insulating member 400 is first connected to the first insulating member 250, and then the cover assembly 200 is connected to the housing 100 to seal the receiving cavity 110.

[0056] Furthermore, the first insulating component 250 and the second insulating component 400, which are connected by a snap-fit ​​mechanism, facilitate installation, reduce the number of hot work operations during the assembly of the cover plate assembly 200, lower the manufacturing difficulty of the secondary battery, and improve the manufacturing efficiency of the secondary battery.

[0057] In some embodiments, referring to Figures 5, 6, and 11, the base 410 has a first connecting hole 411 extending through the base 410 along the thickness direction Z. A portion of the tab 320 passes through the first connecting hole 411 and is connected to the side of the connecting piece 240 opposite to the electrode assembly 300. In other words, a portion of the tab 320 passes through the first connecting hole 411, and a portion of the tab 320 is fixedly connected to the side of the connecting piece 240 opposite to the electrode assembly 300.

[0058] Specifically, when connecting the cover plate assembly 200 and the electrode assembly 300, the tab 320 is first passed through the first connecting hole 411, and then the tab 320 is folded so that part of the tab 320 is located on the side of the connecting piece 240 away from the electrode assembly 300, and then the connecting piece 240 and the tab 320 are welded.

[0059] In the above embodiment, by providing a first connecting hole 411, the connection between the tab 320 and the connecting piece 240 is made to avoid the tab needing to bypass the base 410 along the width direction Y, thereby keeping the tab 320 away from the housing 100 and preventing contact between the tab 320 and the housing 100, further reducing the possibility of a short circuit in the secondary battery. Simultaneously, folding part of the tab 320 onto the side of the connecting piece 240 away from the electrode assembly 300 also facilitates the positioning of the tab 320 during welding, thus reducing the difficulty of connecting the tab 320 and the connecting piece 240. Furthermore, folding the tab 320 onto the side of the connecting piece 240 away from the electrode assembly 300 also reduces the space occupied by the tab 320 in the thickness direction Z of the receiving cavity 110, thereby improving the internal space utilization of the secondary battery, making the secondary battery structure more compact, and improving the volumetric energy density of the secondary battery.

[0060] In some embodiments, please refer to Figures 5 and 6, the connecting piece 240 has a second connecting hole 241 extending through the connecting piece 240 along the thickness direction Z, the second connecting hole 241 communicating with the first connecting hole 411, and a portion of the tab 320 passing through the first connecting hole 411 passing through the second connecting hole 241.

[0061] In the above embodiment, by providing a second connection hole 241, the tab 320 is prevented from needing to go around the side of the connecting piece 240 along the width direction Y when it is connected to the side of the connecting piece 240 away from the electrode assembly 300. This reduces the length of the tab 320 and also reduces the difficulty of connecting the tab 320 to the connecting piece 240.

[0062] Additionally, it is understood that part of the tab 320 can be connected to one side of the second connecting hole 241 along the width direction Y, and part of the tab 320 can be connected to the other side of the second connecting hole 241 along the width direction Y. That is, the connecting piece 240 will be subjected to a force along the thickness direction Z on both sides of the second connecting hole 241 along the width direction Y during the welding process. Elastic parts are provided on both sides of the first connecting hole 411 along the width direction Y to support the welding part of the connecting piece 240 and the tab 320, thereby further improving the support effect of the support member on the connecting piece 240.

[0063] In some embodiments, referring to FIG9, the sealing member 220 has a first surface 221 facing the receiving cavity 110, and along the thickness direction Z, the orthographic projection of the connecting piece 240 on the plane where the first surface 221 is located is located within the orthographic projection of the base 410 on the plane where the first surface 221 is located.

[0064] In other words, the base 410 can completely cover the connecting piece 240 along the thickness direction Z. Please refer to Figure 9, which is a bottom view of the cover plate assembly 200. Since the base 410 can completely cover the connecting piece 240 along the thickness direction Z, the connecting piece 240 is not visible in Figure 9.

[0065] In the above embodiment, since the base 410 completely covers the connecting piece 240 in the thickness direction Z, the probability of the connecting piece 240 contacting the body 310 is further reduced, thereby further improving the reliability of the secondary battery.

[0066] In some embodiments, the sealing member 220 further has an injection hole 222 extending through the sealing member 220 along the thickness direction Z. The base 410 has a diversion region 440, which has a diversion cavity 441 opening toward the injection hole 222 and communicating with the injection hole 222. The diversion region 440 is provided with a first diversion hole 442 extending through the sealing member 220 along the thickness direction Z, and the first diversion hole 442 communicates with the diversion cavity 441 and the receiving cavity 110; the first diversion hole 442 has a first hole wall 443, and the first hole wall 443 is located on the periphery of the injection hole 222 in the orthographic projection of the sealing member 220 along the thickness direction Z.

[0067] Specifically, please refer to Figures 11, 12 and 13. The sealing member 220 has a first surface 221 facing the receiving cavity 110. The sealing member 220 also has an injection hole 222 extending through the sealing member 220 in the thickness direction Z. The injection hole 222 extends through the first surface 221 and communicates with the receiving cavity 110.

[0068] The second insulating member 400 further includes a diversion region 440 extending through the base 410 along the thickness direction Z. The diversion region 440 has a diversion cavity 441 opening towards the injection hole 222. The diversion region 440 has a first diversion hole 442 extending through the diversion region 440 along the thickness direction Z. The first diversion hole 442 has a first hole wall 443. The orthographic projection of the first hole wall 443 along the thickness direction Z onto the plane containing the first surface 221 is located on the periphery of the injection hole 222. The diversion region 440 has a second surface 444 facing the sealing member 220, and the opening of the diversion cavity 441 is located on the second surface 444.

[0069] In some embodiments, the second insulating member 400 is further provided with a diversion groove 450, which penetrates the base 410 and the surface of the support 420 toward the base 410 along the thickness direction Z. The support 420 is provided with a second diversion hole 421 along the thickness direction Z, and the second diversion hole 421 communicates with the diversion groove 450.

[0070] Specifically, the diversion zone 440 has a through groove 445 extending through the diversion zone 440 along the length direction X, the through groove 445 connecting to the diversion cavity 441, and the through groove 445 penetrating the second surface 444. The second insulating member 400 also has a diversion groove 450, which extends through the base 410 and the surface of the support portion 420 facing the base 410 along the thickness direction Z. The support portion 420 is provided with a second diversion hole 421 extending through the support portion along the thickness direction Z, and the second diversion hole 421 communicates with the diversion groove 450.

[0071] In the above embodiment, the orthographic projection of the first hole wall 443 along the thickness direction Z onto the plane containing the first surface 221 is located on the periphery of the injection hole 222. This means that the injection hole 222 and the first diversion hole 442 are offset in the thickness direction Z. The electrolyte entering the receiving cavity 110 through the injection hole 222 is blocked by the diversion area 440, and then flows to the electrode assembly 300 through the first diversion hole 442. This avoids the electrolyte directly rushing towards the electrode assembly 300, which could damage the body 310 of the electrode assembly 300, and reduces the manufacturing difficulty of the secondary battery.

[0072] Furthermore, when the flow rate at the injection hole 222 is greater than the flow rate at the first diversion hole 442, the electrolyte level in the diversion cavity 441 rises until it reaches the through groove 445. The electrolyte flows through the through groove 445 to both sides of the diversion area 440, and part of the electrolyte flows through the first connecting hole 411 to the electrode assembly 300, which enables the electrolyte to flow along the length direction X, thereby making the distribution of the electrolyte in the length direction X more uniform.

[0073] Furthermore, the diversion groove 450 provided in the support part 420 can receive another part of the electrolyte flowing out through the through groove 445, and allow the electrolyte to flow from the second diversion hole 421 to the electrode assembly 300, further allowing the electrolyte to flow in the length direction X, thereby making the distribution of the electrolyte in the length direction X more uniform, ensuring the electrolyte filling efficiency while avoiding damage to the electrode assembly 300 by a large flow of electrolyte.

[0074] In some embodiments, referring to Figures 6 and 11, the cover plate assembly 200 includes a plurality of connecting pieces 240; the second insulating member 400 also includes a protrusion 460 connected to the side of the base 410 along the thickness direction Z close to the connecting piece 240, and at least one connecting piece 240 connected to the side of the protrusion 460 along the thickness direction Z away from the base 410.

[0075] It is understood that in some embodiments, the dimensions of some pole posts 230 along the thickness direction Z are smaller than the dimensions of other pole posts 230 along the thickness direction Z, which leads to different spacing between the connecting piece 240 and the base 410 connected to different pole posts 230 in the thickness direction Z.

[0076] In some embodiments, the dimension of the negative electrode post 230 along the thickness direction Z is smaller than the dimension of the positive electrode post 230 along the thickness direction Z.

[0077] In the above embodiment, by providing the protrusion 460 so that each connecting piece 240 connected to different poles 230 can be supported by the support member, the difficulty of welding the connecting piece 240 and the tab 320 is further reduced, thereby reducing the manufacturing difficulty of the secondary battery and improving the manufacturing efficiency of the secondary battery.

[0078] In some embodiments, referring to FIG13, the cover plate also has a width direction Y. The thickness direction Z, length direction X, and width direction Y intersect each other. The second insulating member 400 includes a plurality of protrusions 460, at least a portion of which are spaced apart along the width direction Y, and at least one connecting piece 240 connects at least two protrusions 460.

[0079] In some embodiments, the plurality of protrusions 460 are also spaced apart along the length direction X.

[0080] In some embodiments, a plurality of protrusions 460 are arranged in an array along the length direction X and the width direction Y.

[0081] In the above embodiment, by setting multiple protrusions 460 spaced apart along the width direction Y, the supporting force of the support member on the connecting piece 240 is uniformly supported in the width direction Y, thereby making the supporting member support the connecting piece 240 better, avoiding deformation of the connecting piece 240 after being subjected to force, and further reducing the welding difficulty of the connecting piece 240 and the tab 320.

[0082] In some embodiments, referring to FIG3, the cover plate has a third surface 214 and a fourth surface 215 that are opposite to each other along the thickness direction Z. The fourth surface 215 faces the receiving cavity 110. The operating port passes through the third surface 214 and the fourth surface 215. The operating port has a second hole wall 212 and a third hole wall 213 connected along the thickness direction Z. The second hole wall 212 is connected to the third surface 214, and the third hole wall 213 is connected to the fourth surface 215. Along the thickness direction Z, the orthographic projection of the third hole wall 213 on the fourth surface 215 is located inside the orthographic projection of the second hole wall 212 on the fourth surface 215. The sealing member 220 is connected to the second hole wall 212.

[0083] In the above embodiment, the second hole wall 212 connected to the sealing member 220 is used to position the sealing member 220 along the length direction X and the width direction Y. After the sealing member 220 contacts the second hole wall 212, it can achieve automatic centering, which facilitates the welding of the sealing member 220 to the cover plate 210. The third hole wall 213 is used to prevent the sealing member 220 from moving towards the receiving cavity 110, that is, the third hole wall 213 can limit the sealing member 220 along the thickness direction Z.

[0084] Furthermore, when the sealing component 220 and the cover plate 210 are laser welded, the third hole wall 213 can block the laser from shooting towards the receiving cavity 110, causing damage to the internal components of the receiving cavity 110, thereby reducing the welding difficulty of the sealing component 220 and the cover plate 210, thereby reducing the manufacturing difficulty of the secondary battery and improving the manufacturing efficiency of the secondary battery.

[0085] In some embodiments, the angle between the second hole wall 212 and the fourth surface 215 is α, and the angle between the third hole wall 213 and the fourth surface 215 is β, satisfying: 30°<α<β<90°.

[0086] By reasonably setting the included angle between the second hole wall 212, the third hole wall 213 and the fourth surface 215, on the one hand, the laser from welding is prevented from entering the receiving cavity 110 as much as possible, and on the other hand, the welding penetration of the sealing component 220 and the cover plate 210 is guaranteed, making the connection between the sealing component 220 and the cover plate 210 more reliable and improving the reliability of the secondary battery.

[0087] Accordingly, this disclosure also provides a battery pack, including the secondary battery as described in the above embodiments.

[0088] The above provides a detailed description of a secondary battery and battery pack provided by the embodiments of this disclosure. Specific examples have been used in this disclosure to illustrate the principles and implementation methods of this disclosure. The description of the above embodiments is only for the purpose of helping to understand the technical solutions and core ideas of this disclosure. Those skilled in the art should understand that they can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this disclosure.

Claims

1. A secondary battery having a thickness direction (Z) and a length direction (X) intersecting each other, wherein include: The housing (100) has a receiving cavity (110); An electrode assembly (300) is disposed in the receiving cavity (110), the electrode assembly (300) including a body (310) and a tab (320) connected to each other; The cover plate assembly (200) includes a cover plate (210), a sealing element (220), a first insulating element (250), a pole (230), and a connecting piece (240); The cover plate (210) is connected to the housing (100) and covers the receiving cavity (110). The cover plate (210) has an operation port (211), which extends through the cover plate (210) along the thickness direction (Z) and communicates with the receiving cavity (110). The sealing element (220) is connected to the cover plate (210), and the sealing element (220) covers the operating port (211); The first insulating member (250) is disposed in the receiving cavity (110) along the thickness direction (Z), and the first insulating member (250) is connected to the cover plate (210) on the side facing the electrode assembly (300); The pole post (230) passes through the cover plate (210) and the first insulating member (250), and the pole post (230) and the sealing member (220) are spaced apart along the length direction (X); The connecting piece (240) is disposed in the receiving cavity (110), and the side of the connecting piece (240) facing away from the electrode assembly (300) is connected to the pole post (230). The electrode tab (320) is electrically connected to the connecting piece (240). At least a portion of the electrode tab (320) and the connecting piece (240) along the thickness direction (Z) on the cover plate (210) are exposed to the operating port (211). A second insulating member (400) is disposed in the receiving cavity (110) and connected to the first insulating member (250). Along the thickness direction (Z), the second insulating member (400) is connected to the side of the body (310) facing the cover plate (210), and the connecting piece (240) is connected to the second insulating member (400) on the side away from the cover plate (210).

2. The secondary battery according to claim 1, wherein The second insulating member (400) includes a base (410) and a support (420). The base (410) is connected to the connecting piece (240) on one side facing the body (310) along the thickness direction (Z). The support (420) is connected between the base (410) and the body (310) along the thickness direction (Z) and connects the base (410) and the body (310) respectively. The tab (320) and the support (420) are spaced apart along the length direction (X).

3. The secondary battery according to claim 2, wherein The pole post (230) passes through the first insulating member (250), and the first insulating member (250) has a second mounting hole (251), which connects the operating port (211) and the receiving cavity (110).

4. The secondary battery according to claim 2, wherein The second insulating member (400) further includes a connecting portion (430) connected to the first insulating member (250), and a portion of the connecting portion (430) is connected to the base (410) along the thickness direction (Z).

5. The secondary battery according to claim 2, wherein The base (410) has a first connection hole (411) extending through the base (410) along the thickness direction (Z), a portion of the tab (320) is disposed through the first connection hole (411), and the tab (320) is connected to the side of the connecting piece (240) opposite to the electrode assembly (300).

6. The secondary battery according to claim 5, wherein The connecting piece (240) has a second connecting hole (241), which extends through the connecting piece (240) along the thickness direction (Z). The second connecting hole (241) communicates with the first connecting hole (411), and the tab (320) that passes through the first connecting hole (411) passes through the second connecting hole (241).

7. The secondary battery according to claim 2, wherein The sealing member (220) has a first surface (221) facing the receiving cavity (110), and the connecting piece (240) is located in the orthographic projection of the first surface (221) along the thickness direction (Z), and is located in the orthographic projection of the base (410) along the thickness direction (Z) in the plane of the first surface (221).

8. The secondary battery according to claim 2, wherein The sealing element (220) also has an injection hole (222) that extends through the sealing element (220) along the thickness direction (Z); The base (410) has a diversion area (440), the diversion area (440) has a diversion cavity (441) with an opening facing the injection hole (222), the diversion cavity (441) is in communication with the injection hole (222); The diversion area (440) is provided with a first diversion hole (442) through it along the thickness direction (Z), and the first diversion hole (442) is connected to the diversion cavity (441) and the receiving cavity (110).

9. The secondary battery according to claim 8, wherein The first diversion hole (442) has a first hole wall (443), and the first hole wall (443) is located on the periphery of the injection hole (222) along the thickness direction (Z) of the sealing member (220).

10. The secondary battery according to claim 8, wherein The diversion area (440) has a second surface (444) facing the sealing member (220), the opening of the diversion cavity (441) is located on the second surface (444), the diversion area (440) also has a through groove (445) extending through the diversion area (440) along the length direction (X), the through groove (445) communicating with the diversion cavity (441), and the through groove (445) extending through the second surface (444).

11. The secondary battery according to claim 2, wherein The second insulating member (400) is also provided with a diversion groove (450), which penetrates the base (410) and the support (420) along the thickness direction (Z) and faces the surface of the base (410). The support (420) is provided with a second diversion hole (421) along the thickness direction (Z) and the second diversion hole (421) communicates with the diversion groove (450).

12. The secondary battery according to claim 2, wherein The cover plate assembly (200) includes a plurality of connecting pieces (240); the second insulating member (400) also includes a protrusion (460) connected to the base (410) along the thickness direction (Z) near the connecting piece (240), and at least one of the connecting pieces (240) connected to the protrusion (460) along the thickness direction (Z) away from the base (410).

13. A battery pack comprising a secondary battery as claimed in any one of claims 1-12.

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