Battery

Abstract

This utility model discloses a battery, comprising: a casing having a receiving cavity, the casing having a lead-out wall surface, the lead-out wall surface having a first through hole communicating with the receiving cavity; a battery cell disposed within the receiving cavity, the battery cell including a tab assembly; a terminal assembly including a terminal body, a connecting piece, and an insulating and sealing connection layer, the connecting piece and the lead-out wall surface being welded together to form a solder mark, the connecting piece having a second through hole, the first through hole and the second through hole corresponding to each other, the terminal body being connected to the tab assembly, the terminal body including a sheet portion and a pillar portion, the pillar portion passing through the first through hole and the second through hole, the sheet portion and the pillar portion being connected, the insulating and sealing connection layer being disposed between the sheet portion and the connecting piece; and an insulating member disposed between the tab assembly and the casing, wherein, in the length direction of the battery, the orthographic projection of the insulating member on the lead-out wall surface at least partially covers the solder mark. The battery of this utility model embodiment not only has good sealing performance and simple manufacturing process, but also high energy density.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, specifically to a battery. Background Technology

[0002] In battery design, the terminals are key components that connect the internal battery cells to the external circuitry, and their sealing directly affects the battery's safety and performance.

[0003] In related technologies, the terminals are usually installed on the battery casing using a press-fit structure. When the battery is under high temperature and vibration conditions, the seal between the terminals and the casing is poor, which poses a risk of leakage. Utility Model Content

[0004] In view of this, the present invention provides a battery to solve the safety risk of electrolyte leakage during high temperature and vibration processes.

[0005] This utility model provides a battery, comprising: a casing having a receiving cavity, the casing having a lead-out wall surface, the lead-out wall surface having a first through hole communicating with the receiving cavity; a battery cell disposed within the receiving cavity, the battery cell including a tab assembly; a terminal assembly including a terminal body, a connecting piece, and an insulating and sealing connection layer, the connecting piece being welded to the lead-out wall surface and forming a solder mark, the connecting piece having a second through hole, the first through hole and the second through hole being correspondingly disposed, the terminal body being electrically connected to the tab assembly, the terminal body including a sheet portion and a column portion, the column portion passing through the first through hole and the second through hole, the sheet portion being connected to the column portion, the insulating and sealing connection layer being disposed between the sheet portion and the connecting piece; and an insulating member disposed between the tab assembly and the casing, wherein, in the length direction of the battery, the orthographic projection of the insulating member on the lead-out wall surface at least partially covers the solder mark.

[0006] Further, the solder mark is formed by recessing inward from the surface of the lead-out wall away from the connecting piece, and the depth of the solder mark is greater than the thickness of the lead-out wall and less than the sum of the thicknesses of the lead-out wall and the connecting piece; and / or, the depth of the solder mark on the connecting piece is H1, the thickness of the connecting piece is D1, and H1 / D1≤3 / 4; and / or, in the length direction of the battery, the distance between the bottom end of the solder mark and the insulating sealing connection layer is H2, and H2 / D1≥1 / 3; and / or, 0.1mm≤D1≤0.5mm; and / or, in the length direction of the battery, the orthographic projection of the solder mark is located within the insulating sealing connection layer.

[0007] Furthermore, the maximum width of the solder mark on the connecting piece is W1, 0.05mm≤W1≤0.25mm; and / or, the width of the insulating sealing connecting layer is W2, W2 / W1≥3.

[0008] Furthermore, the edge of the insulating sealing connection layer has an overflow portion that covers at least a portion of the outer peripheral surface of the sheet portion, and or, the overflow portion covers at least a portion of the outer peripheral surface of the connecting sheet.

[0009] Furthermore, the edge of the connecting piece is provided with a first annular protrusion, the first annular protrusion protrudes in a direction away from the lead-out wall, and the first annular protrusion surrounds the piece body portion; the overflow portion is located between the inner peripheral surface of the first annular protrusion and the outer peripheral surface of the piece body portion.

[0010] Furthermore, the edge of the sheet portion is provided with a second annular protrusion, the second annular protrusion protruding toward the lead-out wall surface, and the second annular protrusion surrounding the connecting piece; the overflow portion is located between the inner peripheral surface of the second annular protrusion and the outer peripheral surface of the connecting piece.

[0011] Furthermore, the battery cell further includes an adapter piece disposed within the receiving cavity, the adapter piece being connected to the electrode assembly; the connecting piece is disposed on the side of the lead-out wall facing away from the receiving cavity, the sheet portion is disposed on the side of the connecting piece facing away from the receiving cavity, the cylindrical portion extends toward the receiving cavity, and the cylindrical portion is connected to the electrode adapter piece; and / or, the battery cell further includes an adapter piece disposed within the receiving cavity, the adapter piece being connected to the electrode assembly; the connecting piece is disposed on the side of the lead-out wall facing away from the receiving cavity, the sheet portion is disposed on the side of the connecting piece facing away from the receiving cavity, the sheet portion is connected to the adapter piece, and the cylindrical portion extends in a direction away from the receiving cavity.

[0012] Furthermore, the outer contour of the insulating sealing connection layer is elliptical, the major axis of the insulating sealing connection layer is L1, the minor axis of the insulating sealing connection layer is L2, L1≥2.5mm, and / or, L2≥2mm, and / or, L1 / L2≥1.1; or, the outer contour of the insulating sealing connection layer is circular, and the outer diameter of the insulating sealing connection layer is not less than 2mm.

[0013] Further, the sheet portion is located outside the receiving cavity, and the cylindrical portion extends into the receiving cavity. The dimension of the cylindrical portion extending beyond the lead-out wall surface facing the receiving cavity is L3, where 0.05mm ≤ L3 ≤ 0.2mm; and / or, in the radial direction of the pole assembly, the distance between the outer peripheral surface of the sheet portion and the outer peripheral surface of the connecting piece is not greater than 0.2mm; and / or, the diameter of the first through hole is greater than the diameter of the second through hole; and / or, the distance between the outer peripheral surface of the cylindrical portion and the inner peripheral surface of the first through hole is H3, where H3 ≥ 0.1mm. ; and / or, the thickness of the sheet portion is D3, 0.15mm≤D3≤0.5mm; and / or, the insulating sealing connection layer includes a first connection layer and a second connection layer, the first connection layer is connected to the sheet portion, the second connection layer is disposed between the first connection layer and the connecting sheet, the melting point of the first connection layer is T1, the melting point of the second connection layer is T2, 100℃≤T1≤150℃, 140℃≤T2≤190℃; and / or, the thickness of the insulating sealing connection layer is D4, 0.02mm≤D4≤0.1mm.

[0014] Further, the housing includes a shell portion and a cover plate. The shell portion has the lead-out wall surface and a skirt. The skirt is connected to the lead-out wall surface and is located on the side of the lead-out wall surface facing away from the receiving cavity. The cover plate is connected to the skirt. The shell portion and the cover plate together define the receiving cavity. The thickness of the skirt is D5, the thickness of the lead-out wall surface is D6, and D5 < D6; and / or, the thickness of the skirt is D5, 0.05mm ≤ D5 ≤ 0.15mm; and / or, the width of the skirt is W3, 0.05mm ≤ W3 ≤ 0.3mm.

[0015] Beneficial Effects: In this invention, by welding the connecting piece and the lead-out wall to form a weld mark, compared to the riveting and bonding techniques of the prior art, welding can prevent the safety risk of electrolyte leakage during high temperature and vibration processes. Moreover, compared to another connection method in the prior art, which uses sealant to fix the terminal post and the shell, and optimizes the battery's working performance under high temperature and vibration conditions, but requires nickel plating and passivation treatment of the shell, making the manufacturing process more complex, this embodiment eliminates the need for prior nickel plating and passivation treatment of the shell, allowing for direct welding, further simplifying the process. By providing an insulating and sealing connection layer between the connecting piece and the plate body, the relative position between the terminal post body and the connecting piece can be fixed, increasing the sealing effect of the connecting piece and the plate body. On the other hand, it can insulate the connecting piece and the terminal post body, preventing short circuits and improving battery safety. By setting up insulating components, the adapter plate and the housing can be separated. On the one hand, this reduces the probability of contact between the solder mark, the tab, and the adapter plate, thus reducing the risk of short circuit. On the other hand, it eliminates the need for additional solder mark protection adhesive, reduces the number of parts in the housing cavity, increases the volume of the cell, improves the space utilization rate in the housing cavity, and thus increases the energy density. Attached Figure Description

[0016] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0017] Figure 1 This is one of the exploded views of the battery in the embodiments of this utility model.

[0018] Figure 2 This is the second exploded view of the battery in this embodiment of the present invention.

[0019] Figure 3 This is one of the cross-sectional views of the sheet portion located outside the receiving cavity in an embodiment of this utility model.

[0020] Figure 4 This is a second cross-sectional view of the sheet portion located outside the receiving cavity in an embodiment of this utility model.

[0021] Figure 5 This is a cross-sectional view of the sheet portion disposed within the receiving cavity in an embodiment of this utility model.

[0022] Figure 6 This is a cross-sectional view of the connecting piece having a first annular protrusion in an embodiment of this utility model.

[0023] Figure 7This is a cross-sectional view of the sheet portion having a second annular protrusion in an embodiment of the present invention.

[0024] Explanation of reference numerals in the attached figures:

[0025] 1. Battery;

[0026] 100. Shell; 101. Receiving cavity; 110. Lead-out wall; 111. First through hole; 120. Skirt; 130. Shell portion;

[0027] 200. Battery cell; 210. Electrode assembly;

[0028] 300, Terminal assembly; 310, Terminal body; 311, Plate portion; 312, Post portion; 314, Second annular protrusion; 320, Connecting piece; 321, Second through hole; 323, First annular protrusion; 324, Solder mark; 330, Insulating and sealing connection layer; 331, Overflow portion;

[0029] 400, adapter plate; 500, insulating component; 600, cover plate. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0031] The embodiments of this utility model will be described below with reference to the accompanying drawings and preferred embodiments. 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, and 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. It should be understood that the preferred embodiments are only for illustrating this utility model and not for limiting the scope of protection of this utility model.

[0032] It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Therefore, the drawings only show the components related to the present invention and are not drawn according to the number, shape and size of the components in actual implementation. 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.

[0033] The following is combined Figures 1 to 7 The following describes embodiments of the present invention.

[0034] This utility model embodiment proposes a battery 1, which includes a casing 100, a cell 200, an adapter piece 400, an electrode assembly 300, and an insulating component 500.

[0035] The housing 100 has a receiving cavity 101 and a lead-out wall 110. The lead-out wall 110 is provided with a first through hole 111, which communicates with the receiving cavity 101.

[0036] A battery cell 200 is disposed within a receiving cavity 101, and the battery cell 200 includes a tab assembly 210. In one embodiment, the battery cell 200 includes a positive electrode sheet (not shown), a negative electrode sheet (not shown), and a separator (not shown) located between the positive electrode sheet and the negative electrode sheet. The positive electrode sheet includes a positive current collector and a positive electrode tab extending from one side of the positive current collector, and a plurality of positive electrode tabs are stacked to form the tab assembly 210; the negative electrode sheet includes a negative current collector and a negative electrode tab extending from one side of the negative current collector, and a plurality of negative electrode tabs are stacked to form the tab assembly 210; the negative electrode sheet also includes a negative active coating located on at least one surface of the negative current collector. In some embodiments, the battery cell 200 may be a wound core formed by stacking and winding a positive electrode sheet, a separator, and a negative electrode sheet; in other embodiments, the battery cell 200 may be a stacked core formed by stacking a positive electrode sheet, a separator, and a negative electrode sheet.

[0037] In a further embodiment, the stacked core includes a topmost and a bottommost electrode sheet along the thickness direction. The topmost and / or bottommost electrode sheet may be a single-sided negative electrode sheet. The single-sided negative electrode sheet includes a negative current collector and a negative active layer on the side surface of the negative current collector near the center of the cell 200.

[0038] In other embodiments, the thickness of the current collector of the topmost electrode is greater than the thickness of the current collector of the same polarity electrodes in the middle of the stack, in order to prevent the topmost electrode from warping due to uneven stress during charging and discharging because it has an active layer on only one side.

[0039] In some embodiments, the positive electrode current collector may comprise aluminum foil, aluminum alloy foil, or a composite current collector (e.g., an aluminum-carbon composite current collector). The composite current collector can be formed by depositing a metallic material (copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver, and silver alloy, etc.) onto a polymer substrate. In some embodiments, the thickness of the positive electrode current collector is 4 μm-12 μm, for example, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, 10 μm, 11 μm, or 12 μm.

[0040] In some embodiments, the positive electrode sheet includes a positive electrode active layer located on the positive electrode current collector. The positive electrode active material of the positive electrode active layer may include at least one of lithium nickel cobalt manganese oxide (LiNi0.90Co0.05Mn0.05O2 (NCM955), NCM811, NCM622, NCM523, NCM111), lithium nickel cobalt aluminum oxide, lithium iron phosphate, lithium vanadium phosphate, lithium cobalt phosphate, lithium manganese phosphate, lithium manganese iron phosphate, lithium-rich manganese-based materials, lithium cobalt oxide (LiCoO2), lithium iron silicate, lithium vanadium silicate, lithium cobalt silicate, lithium manganese silicate, spinel-type lithium manganese oxide, spinel-type lithium nickel manganese oxide, and lithium titanate. In some embodiments, the thickness of the positive electrode active layer is 30 μm-110 μm, for example, 30 μm, 40 μm, 50 μm, 60 μm, 70 μm, 80 μm, 90 μm, 100 μm, or 110 μm.

[0041] In some embodiments, the positive electrode sheet further includes a positive electrode binder and a positive electrode conductive agent. For example, the positive electrode binder may include, but is not limited to, at least one of polyvinylidene fluoride, polytetrafluoroethylene, polyolefins, sodium carboxymethyl cellulose, lithium carboxymethyl cellulose, modified polyvinylidene fluoride, modified styrene-butadiene rubber (SBR), or polyurethane. In some embodiments, the polyolefin binder includes at least one of polyethylene, polypropylene, polyolefin ester, polyenol, or polyacrylic acid. In some embodiments, the positive electrode conductive agent includes at least one of carbon-based materials, such as natural graphite, artificial graphite, carbon black, acetylene black, Ketjen black, carbon fiber, metal-based materials, and conductive polymers. The metal-based material may be, for example, metal powder or metal fiber of copper, nickel, aluminum, silver, etc. The conductive polymer may be, for example, a polyphenylene derivative.

[0042] In some embodiments, the negative electrode current collector may include, but is not limited to, copper foil, copper alloy foil, nickel foil, stainless steel foil, titanium foil, nickel foam, copper foam, or composite current collectors (e.g., carbon-copper composite current collectors, nickel-copper composite current collectors, titanium-copper composite current collectors, etc.). In some embodiments, the thickness of the negative electrode current collector is 3μm-12μm, for example, 3μm, 4μm, 5μm, 6μm, 7μm, 8μm, 9μm, 10μm, 11μm, or 12μm.

[0043] In some embodiments, the negative electrode active coating includes a negative electrode active material, which includes a silicon-based material; the silicon-based material includes at least one selected from elemental silicon, silicon oxide, silicon carbon, and silicon alloys. In some embodiments, the mass content of elemental silicon in the negative electrode active coating is 1.5%-50%, for example, 1.5%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, or 50%.

[0044] The terminal assembly 300 includes a terminal body 310, a connecting piece 320, and an insulating and sealing connection layer 330. The connecting piece 320 is welded to the lead-out wall 110, forming a solder mark 324. The connecting piece 320 is provided with a second through hole 321, and the first through hole 111 and the second through hole 321 are correspondingly provided. The terminal body 310 is connected to the tab assembly 210. The terminal body 310 includes a sheet portion 311 and a pillar portion 312. The pillar portion 312 passes through the first through hole 111 and the second through hole 321. The sheet portion 311 and the pillar portion 312 are connected. The insulating and sealing connection layer 330 is disposed between the sheet portion 311 and the connecting piece 320. An insulating member 500 is disposed between the tab assembly 210 and the housing 100. In the length direction of the battery 1, the orthographic projection of the insulating member 500 on the lead-out wall 110 at least partially covers the solder mark 324.

[0045] For example, the connecting piece 320 and the lead-out wall 110 can be sealed by laser welding. The connecting piece 320 can be made of nickel-plated stainless steel or nickel. The surface of the connecting piece 320 is provided with chromium oxide, and the chromium content in the chromium oxide is greater than or equal to 100 PPM, which improves the sealing performance and corrosion resistance of the connecting piece 320. The insulating sealing connection layer 330 can be polypropylene (PP) adhesive. In one embodiment, for example, before the battery cell 200 and the tab assembly 210 are placed into the housing 100, the connecting piece 320 and the through hole of the lead-out wall 110 are positioned. Then, laser welding is performed on the side of the lead-out wall 110 away from the connecting piece 320, and a weld mark 324 is formed on the inner surface of the lead-out wall 110. Subsequently, the battery cell 200 is placed into the housing 100, and the insulating member 500 at least partially covers the weld mark 324 on the lead-out wall 110.

[0046] In this embodiment of the utility model, by welding the connecting piece 320 and the lead-out wall 110 to form a weld mark 324, compared with the riveting and bonding techniques of the prior art, welding can not only prevent the safety risk of electrolyte leakage of battery 1 during high temperature and vibration processes, but also optimize the working performance of battery under high temperature and vibration conditions compared with another connection method in the prior art, that is, using sealant to fix the terminal and the shell, but the shell needs to be nickel-plated and passivated, which is a more complicated manufacturing process. The solution of this embodiment does not require the shell 100 to be nickel-plated and passivated in advance, and can be directly welded, further simplifying the process.

[0047] In addition, by providing an insulating and sealing connection layer 330 between the connecting piece 320 and the plate body 311, the relative position between the terminal body 310 and the connecting piece 320 can be fixed, increasing the sealing effect between the connecting piece 320 and the plate body 311. On the other hand, the connecting piece 320 and the terminal body 310 can be insulated to avoid short circuit problems in the battery 1 and improve the safety of the battery 1.

[0048] The battery 1 can have multiple tab assemblies 210, one of which is a positive tab assembly 210 and the other is a negative tab assembly 210. The positive tab assembly 210 can be connected to the terminal body 310 via an adapter 400, and the negative tab assembly 210 can be connected to the housing 100. Alternatively, the negative tab assembly 210 can be connected to the terminal body 310 via an adapter 400, and the positive tab assembly 210 can be connected to the housing 100. In this way, the housing 100 can be used as either a positive or negative terminal, resulting in fewer parts and a simpler structure for the battery 1.

[0049] By setting the insulating component 500, the tab assembly 2100 and the housing 100 can be separated. On the one hand, this reduces the probability of contact between the solder 324, the tab assembly 210, and the adapter piece 400, thus reducing the risk of short circuit. On the other hand, it eliminates the need for additional solder protective adhesive, reduces the number of parts in the housing cavity 101, increases the volume of the cell 200, improves the space utilization rate in the housing cavity 101, and thereby increases the energy density.

[0050] In some embodiments, such as Figures 3-5 As shown, solder mark 324 is formed by indentation from the side surface of lead-out wall 110 away from connecting piece 320. The depth of solder mark 324 is greater than the thickness of lead-out wall 110 and less than the sum of the thicknesses of lead-out wall 110 and connecting piece 320.

[0051] In this way, the solder stamp 324 passes through the lead-out wall 110 and contacts the connecting piece 320. The large welding area between the lead-out wall 110 and the connecting piece 320 improves the welding reliability between them, and correspondingly enhances the sealing performance. Furthermore, the solder stamp 324 does not penetrate the connecting piece 320, creating a gap between the solder stamp 324 and the insulating sealing connection layer 330. This prevents the insulating sealing connection layer 330 from melting due to heat, ensuring its sealing effect.

[0052] Furthermore, such as Figure 3As shown, the depth of the solder mark 324 on the connecting piece 320 is H1, and the thickness of the connecting piece 320 is D1, where H1 / D1 ≤ 3 / 4. When the connecting piece 320 and the lead-out wall surface 110 are welded, the heat from the welding may be transferred to the insulating sealing connection layer 330, which may easily cause partial melting of the insulating sealing connection layer 330, thereby reducing the sealing performance of the insulating sealing connection layer 330. Therefore, by setting the distance between the solder mark 324 and the insulating sealing connection layer 330 to be greater than 1 / 4 of the thickness of the connecting piece 320, the probability of the welding heat being transferred to the insulating sealing connection layer 330 can be reduced, ensuring the sealing effect of the insulating sealing connection layer 330.

[0053] Specifically, such as Figure 3 As shown, along the length of battery 1, the distance between the bottom of solder mark 324 and the insulating sealing connection layer 330 is H2, where H2 / D1 ≥ 1 / 3. This ensures that the distance between solder mark 324 and the insulating sealing connection layer 330 is not less than 1 / 3 of the thickness of the connecting piece 320, effectively preventing the insulating sealing connection layer 330 from melting due to heat, resulting in a better sealing effect.

[0054] Wherein, 0.1mm≤D1≤0.5mm, preferably 0.15mm≤D1≤0.3mm, and D1 can be 0.1mm, 0.15mm, 0.2mm, 0.25mm, 0.3mm, 0.35mm, 0.4mm, 0.45mm, or 0.5mm. Thus, the thickness of the connecting piece 320 is not less than 0.1mm, and the thickness of the connecting piece 320 is sufficiently large to increase the welding area between the solder mark 324 and the connecting piece 320, improving welding reliability, and also to ensure sufficient spacing between the solder mark 324 and the insulating sealing connection layer 330, reducing the probability of the insulating sealing connection layer 330 melting. The thickness of the connecting piece 320 is not greater than 0.5mm, which not only reduces cost but also lightens the weight and volume of the terminal assembly 300, facilitating the miniaturization of the battery 1. The battery 1 has a more compact structure, making it easier to apply the battery 1 in a small space.

[0055] In some embodiments, such as Figures 3-5 As shown, along the length of battery 1, the orthographic projection of solder mark 324 is located within the insulating and sealing connection layer 330. While ensuring the welding strength meets the requirements, the width of the insulating and sealing connection layer 330 can be effectively increased, and the design requirements of thin battery 1 are met. This not only improves the sealing performance of battery 1, but also enhances its safety and reliability, and reduces manufacturing costs.

[0056] In some embodiments, such as Figure 3As shown, the maximum width of the solder mark 324 on the connecting piece 320 is W1, where 0.05mm ≤ W1 ≤ 0.25mm. W1 can be 0.05mm, 0.1mm, 0.15mm, 0.2mm, or 0.25mm. By setting W1 to be no less than 0.05mm, the welding area between the solder mark 324 and the connecting piece 320 is sufficiently large, improving welding reliability and sealing performance. By setting W1 to be no greater than 0.25mm, excessively large solder marks 324 are avoided, reducing energy consumption and decreasing the probability of welding heat transfer to the insulating sealing connection layer 330, thereby preventing the insulating sealing connection layer 330 from melting and ensuring sealing performance.

[0057] In some embodiments, such as Figure 4 As shown, the width of the insulating sealing connection layer 330 is W2, and W2 / W1 ≥ 3. This effectively increases the width of the insulating sealing connection layer 330, improving the sealing performance of the battery 1. Since the width of the insulating sealing connection layer 330 is much larger than the maximum width of the solder mark 324 on the connecting piece 320, the width of the insulating sealing connection layer 330 is large enough that even if the insulating sealing connection layer 330 is locally heated and melted, it will not excessively affect the sealing performance of the insulating sealing connection layer 330, thus reducing the impact of welding on the sealing performance of the insulating sealing connection layer 330.

[0058] In some embodiments, such as Figures 3-5 As shown, the edge of the insulating sealing connection layer 330 has an overflow portion 331, which covers at least a portion of the outer peripheral surface of the sheet portion 311, or the overflow portion 331 covers at least a portion of the outer peripheral surface of the connecting piece 320, or the overflow portion 331 covers at least a portion of the outer peripheral surface of the sheet portion 311 and at least a portion of the outer peripheral surface of the connecting piece 320.

[0059] This increases the volume of the insulating sealing connection layer 330, which not only improves the gap between the sealing sheet body 311 and the connecting sheet 320 of the insulating sealing connection layer 330, thus optimizing the sealing effect, but also increases the structural stability of the pole assembly 300.

[0060] Furthermore, such as Figure 6 As shown, the edge of the connecting piece 320 is provided with a first annular protrusion 323, which protrudes in a direction away from the lead-out wall surface 110 and surrounds the piece body portion 311. The overflow portion 331 is located between the inner peripheral surface of the first annular protrusion 323 and the outer peripheral surface of the piece body portion 311.

[0061] By providing the first annular protrusion 323, the positioning effect between the pole body 310 and the connecting piece 320 can be increased, thereby improving the structural strength of the pole assembly 300. Furthermore, by providing the overflow portion 331 between the first annular protrusion 323 and the piece portion 311, the sealing area between the pole body 310 and the connecting piece 320 can be increased, thereby improving the sealing effect.

[0062] Or, such as Figure 7 As shown, a second annular protrusion 314 is provided on the edge of the sheet portion 311. The second annular protrusion 314 protrudes toward the lead-out wall surface 110 and surrounds the connecting piece 320. The overflow portion 331 is located between the inner peripheral surface of the second annular protrusion 314 and the outer peripheral surface of the connecting piece 320.

[0063] By providing the second annular protrusion 314, the positioning effect between the pole body 310 and the connecting piece 320 can be increased, thereby improving the structural strength of the pole assembly 300. Furthermore, by providing the overflow portion 331 between the second annular protrusion 314 and the connecting piece 320, the sealing area between the pole body 310 and the connecting piece 320 can be increased, thereby improving the sealing effect.

[0064] In some embodiments, the battery cell 200 further includes an adapter piece 400 disposed within the receiving cavity 101 and connected to the electrode assembly 210. In some embodiments, the adapter piece 400 is U-shaped, S-shaped, or Z-shaped.

[0065] In some embodiments, such as Figures 3-4 , Figure 6 and Figure 7 As shown, the connecting piece 320 is disposed on the side of the lead-out wall 110 facing away from the receiving cavity 101, the piece body portion 311 is disposed on the side of the connecting piece 320 facing away from the receiving cavity 101, and the column portion 312 extends toward the receiving cavity 101 and is connected to the adapter piece 400.

[0066] In this way, the connecting piece 320, the piece body 311 and the insulating sealing connecting layer 330 are located outside the receiving cavity 101, and the column part 312 extends into the receiving cavity 101 and connects with the adapter piece 400. This can reduce the volume of the receiving cavity 101, thereby reducing the volume of the housing 100, reducing cost and weight, and facilitating the miniaturization of the battery 1.

[0067] Or, such as Figure 5 As shown, the connecting piece 320 is disposed on the side of the lead-out wall 110 facing the receiving cavity 101, the piece body 311 is disposed on the side of the connecting piece 320 facing away from the receiving cavity 101, the piece body 311 is connected to the adapter piece 400, and the column part 312 extends in the direction away from the receiving cavity 101.

[0068] In this way, the connecting piece 320, the piece body 311, and the insulating and sealing connecting layer 330 are located outside the receiving cavity 101, and the column part 312 extends out of the receiving cavity 101. The column part 312 is used to connect with external electrical components. The connecting piece 320, the piece body 311, and the insulating and sealing connecting layer 330 can, to a certain extent, isolate the adapter piece 400 and the housing 100, reducing the probability of the adapter piece 400 and the housing 100 coming into contact when the battery 1 is dropped or collided, thus improving the safety of the battery 1.

[0069] In some embodiments, the outer contour of the insulating sealing connection layer 330 is elliptical, with the major axis of the insulating sealing connection layer 330 being L1 and the minor axis being L2. L1 ≥ 2.5 mm, and / or L2 ≥ 2 mm, and / or L1 / L2 ≥ 1.1. Wherein, L1 can be 2.5 mm, 2.6 mm, 2.7 mm, 2.7 mm, 2.9 mm, or 3 mm; L2 can be 2 mm, 2.1 mm, 2.2 mm, 2.3 mm, 2.4 mm, or 2.5 mm; and L1 / L2 can be 1.1, 1.2, 1.3, 1.4, or 1.5.

[0070] This increases the area surrounded by the outer contour of the insulating sealing connection layer 330, and thus the area surrounded by the outer contour of the electrode body 310 can also be increased. In other words, the cross-sectional area of ​​the electrode body 310 can be increased, thereby increasing the current carrying capacity of the electrode body 310. Furthermore, the welding process window between the electrode body 310 and the adapter piece 400 can also be increased, thereby improving the working performance of the battery 1.

[0071] Alternatively, the outer contour of the insulating sealing connection layer 330 may be circular, and the outer diameter of the insulating sealing connection layer 330 may be greater than or equal to 2 mm. The outer diameter of the insulating sealing connection layer 330 may be 2 mm, 2.1 mm, 2.2 mm, 2.3 mm, 2.4 mm, or 2.5 mm.

[0072] In this way, the sealing width of the insulating sealing connection layer 330 is sufficient to ensure that the cross-sectional area of ​​the electrode body 310 is large enough, guaranteeing the current carrying capacity of the electrode body 310 and the process window for welding between the electrode body 310 and the adapter piece 400, thereby ensuring sufficient working performance of the battery 1. In addition, the insulating sealing connection layer 330 is simple to process and does not require regional installation angles, which helps to improve production efficiency.

[0073] In some embodiments, such as Figure 4As shown, the sheet portion 311 is located outside the receiving cavity 101, and the cylindrical portion 312 extends into the receiving cavity 101. The dimension of the cylindrical portion 312 extending beyond the surface of the lead-out wall 110 facing the receiving cavity 101 is L3, where 0.05mm≤L3≤0.2mm. L3 can be 0.05mm, 0.1mm, 0.15mm, or 0.2mm.

[0074] For example, the ratio of the height of the column portion 312 to the thickness of the insulating sealing connection layer 330 is greater than or equal to 4.

[0075] L3 is not less than 0.05mm. After the column part 312 and the adapter piece 400 are welded, the distance between the adapter piece 400 and the housing 100 is not less than 0.05mm. The adapter piece 400 is insulated from the inner wall of the housing 100, which ensures high safety. L3 is not greater than 0.2mm, which avoids the column part 312 from occupying too much volume in the cavity 101 and improves the energy density of the battery 1.

[0076] In some embodiments, the radial deviation between the outer peripheral surface of the plate portion 311 and the outer peripheral surface of the connecting piece 320 in the pole assembly 300 is no greater than 0.2 mm. The deviation between the outer peripheral surface of the plate portion 311 and the outer peripheral surface of the connecting piece 320 can be 0.01 mm, 0.05 mm, 0.1 mm, 0.15 mm, or 0.2 mm.

[0077] This reduces the probability of misalignment between the outer peripheral surfaces of the sheet portion 311 and the connecting piece 320, which is beneficial to improving the sealing effect of the insulating sealing connection layer 330 on the sheet portion 311 and the connecting piece 320.

[0078] In some embodiments, such as Figure 5 As shown, the thickness of the sheet portion 311 is D3, 0.15mm≤D3≤0.5mm, where D3 can be 0.15mm, 0.2mm, 0.25mm, 0.3mm, 0.35mm, 0.4mm, 0.45mm or 0.5mm.

[0079] The thickness of the sheet portion 311 is not less than 0.15 mm, which improves the structural strength of the sheet portion 311 and reduces the probability of deformation damage; the thickness of the sheet portion 311 is not greater than 0.5 mm, which reduces the cost and weight of the sheet portion 311.

[0080] In some embodiments, such as Figure 3 and Figure 4As shown, the diameter of the first through hole 111 is larger than the diameter of the second through hole 321. This allows for a larger area on the connecting piece 320 for arranging the insulating sealing connecting layer 330, increasing its width. The inner diameter of the insulating sealing connecting layer 330 can be smaller than the diameter of the second through hole 321. The insulating sealing connecting layer 330 can be directly connected to the pillar portion 312, or even located between the outer circumferential surface of the pillar portion 312 and the inner circumferential surface of the connecting piece 320. This improves the sealing effect and reduces the probability of contact between the connecting piece 320 and the pillar portion 312, thus reducing the risk of short circuits and improving the safety of the battery 1.

[0081] In some embodiments, such as Figure 4 As shown, the distance between the outer peripheral surface of the pillar portion 312 and the inner peripheral surface of the first through hole 111 is H3, where H3 ≥ 0.1 mm. H3 can be 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, or 0.5 mm. This prevents the pillar portion 312 from contacting the casing 100, reducing the risk of short circuits and improving the safety of the battery 1.

[0082] In some embodiments, the insulating sealing connection layer 330 includes a first connection layer and a second connection layer. The first connection layer is connected to the sheet portion 311, and the second connection layer is disposed between the first connection layer and the connecting piece 320. The melting point of the first connection layer is T1, and the melting point of the second connection layer is T2, where 100℃≤T1≤150℃ and 140℃≤T2≤190℃. The sum of the thicknesses of the first and second connection layers is greater than or equal to 0.02mm and less than or equal to 0.1mm.

[0083] For example, T1 can be 100℃, 105℃, 110℃, 115℃, 120℃, 125℃, 130℃, 135℃, 140℃, 145℃, or 150℃. T2 can be 140℃, 145℃, 150℃, 155℃, 160℃, 165℃, 170℃, 175℃, 180℃, 185℃, or 190℃.

[0084] Because the second connecting layer is less prone to melting and is closer to the connecting piece 320, the insulating sealing connecting layer 330 is less likely to melt during welding of the connecting piece 320, thus ensuring the sealing effect of the insulating sealing connecting layer 330. By setting the first connecting layer, the cost of the first connecting layer can be lower than that of the second connecting layer, so that the thickness of the insulating sealing connecting layer 330 meets the requirements, ensuring the positioning effect and sealing performance between the pole body 310 and the connecting piece 320.

[0085] In some embodiments, such as Figures 1-3As shown, the housing 100 includes a housing portion 130 and a cover plate 600. The housing portion 130 has an extension wall 110 and a skirt 120. The skirt 120 is connected to the extension wall 110 and is located on the side of the extension wall 110 facing away from the receiving cavity 101. The cover plate 600 is connected to the skirt 120. The housing portion 130 and the cover plate 600 together define the receiving cavity 101.

[0086] The thickness of the cover plate 600 is less than or equal to the thickness of the lead-out wall 110, and a pressure relief valve may be provided on the cover plate 600. The depth of the pressure relief valve is greater than or equal to half the thickness of the cover plate 600 to ensure the pressure relief effect.

[0087] This achieves a sealing effect for the cavity 101, and the connection area between the housing 100 and the cover plate 600 is large. The housing 100 and the cover plate 600 can be welded together, which helps to improve the reliability of the relative position between the housing 100 and the cover plate 600.

[0088] Furthermore, such as Figures 1-3 As shown, the thickness of the skirt 120 is D5, and the thickness of the lead-out wall 110 is D6, where D5 < D6. By setting the thickness of the skirt 120 to be less than the thickness of the lead-out wall 110, the width of the skirt 120 can be increased, thereby increasing the process window for welding the skirt 120 and the cover plate 600, and improving the connection effect between the housing 100 and the cover plate 600.

[0089] Furthermore, such as Figures 1-3 As shown, the thickness of the skirt 120 is D5, 0.05mm ≤ D5 ≤ 0.15mm. D5 can be 0.05mm, 0.1mm, or 0.15mm. This ensures that the thickness of the skirt 120 is not less than 0.05mm, preventing it from being too thin and reducing the probability of deformation and damage; and that the thickness is not greater than 0.15mm, guaranteeing a sufficiently large thickness to improve the welding process window between the skirt 120 and the cover plate 600, resulting in a more reliable connection and seal between the cover plate 600 and the housing 100.

[0090] Furthermore, such as Figures 1-3 As shown, the width of the skirt 120 is W3, 0.05mm≤W3≤0.3mm. This ensures that the width of the skirt 120 is not less than 0.05mm, preventing it from being too small and improving the welding process window between the skirt 120 and the cover plate 600, making the connection and sealing between the cover plate 600 and the housing 100 more reliable. Conversely, the width of the skirt 120 is not greater than 0.3mm, preventing it from being too large, thus ensuring the connection strength meets requirements while reducing the weight and cost of the battery 1.

[0091] The above embodiments are merely preferred embodiments provided to fully illustrate the present utility model, and the protection scope of the present utility model is not limited thereto. Equivalent substitutions or modifications made by those skilled in the art based on the present utility model are all within the protection scope of the present utility model.

[0092] Although embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A battery, characterized in that, include: The housing (100) has a receiving cavity (101) and a lead-out wall (110) is provided with a first through hole (111) which communicates with the receiving cavity (101). A battery cell (200) is disposed within the receiving cavity (101), the battery cell (200) including a tab assembly (210); The electrode assembly (300) includes an electrode body (310), a connecting piece (320), and an insulating and sealing connection layer (330). The connecting piece (320) is welded to the lead-out wall (110) and forms a solder mark (324). The connecting piece (320) is provided with a second through hole (321). The first through hole (111) and the second through hole (321) are correspondingly provided. The electrode body (310) is electrically connected to the electrode tab assembly (210). The electrode body (310) includes a sheet portion (311) and a pillar portion (312). The pillar portion (312) passes through the first through hole (111) and the second through hole (321). The sheet portion (311) is connected to the pillar portion (312). The insulating and sealing connection layer (330) is disposed between the sheet portion (311) and the connecting piece (320). An insulating element (500) is disposed between the tab assembly (210) and the housing (100). In the longitudinal direction of the battery (1), the orthographic projection of the insulating element (500) on the lead-out wall (110) at least partially covers the solder mark (324).

2. The battery according to claim 1, characterized in that, The solder mark (324) is formed by recessing inward from the side surface of the lead-out wall (110) away from the connecting piece (320). The depth of the solder mark (324) is greater than the thickness of the lead-out wall (110) and less than the sum of the thicknesses of the lead-out wall (110) and the connecting piece (320). And / or, the depth of the solder mark (324) on the connecting piece (320) is H1, the thickness of the connecting piece (320) is D1, and H1 / D1≤3 / 4; And / or, in the length direction of the battery (1), the distance between the bottom end of the solder mark (324) and the insulating sealing connection layer (330) is H2, H2 / D1≥1 / 3; And / or, 0.1mm≤D1≤0.5mm; And / or, in the length direction of the battery (1), the orthographic projection of the solder mark (324) is located within the insulating sealing connection layer (330).

3. The battery according to claim 1, characterized in that, The maximum width of the solder mark (324) on the connecting piece (320) is W1, 0.05mm≤W1≤0.25mm; And / or, the width of the insulating sealing connection layer (330) is W2, where W2 / W1≥3.

4. The battery according to claim 1, characterized in that, The edge of the insulating sealing connection layer (330) has an overflow portion (331) that covers at least a portion of the outer peripheral surface of the sheet portion (311), and or, the overflow portion (331) covers at least a portion of the outer peripheral surface of the connecting piece (320).

5. The battery according to claim 4, characterized in that, The edge of the connecting piece (320) is provided with a first annular protrusion (323), the first annular protrusion (323) protrudes in a direction away from the lead-out wall (110), and the first annular protrusion (323) surrounds the piece body (311); The overflow portion (331) is located between the inner peripheral surface of the first annular protrusion (323) and the outer peripheral surface of the sheet portion (311).

6. The battery according to claim 4, characterized in that, The edge of the sheet portion (311) is provided with a second annular protrusion (314), the second annular protrusion (314) protrudes toward the lead-out wall surface (110), and the second annular protrusion (314) surrounds the connecting piece (320); The overflow portion (331) is located between the inner peripheral surface of the second annular protrusion (314) and the outer peripheral surface of the connecting piece (320).

7. The battery according to any one of claims 1-6, characterized in that, The battery cell (200) also includes an adapter piece (400) disposed in the receiving cavity (101), the adapter piece (400) being connected to the electrode assembly (210); the connecting piece (320) is disposed on the side of the lead-out wall (110) facing away from the receiving cavity (101), the piece body portion (311) is disposed on the side of the connecting piece (320) facing away from the receiving cavity (101), the column portion (312) extends toward the receiving cavity (101), and the column portion (312) is connected to the adapter piece (400); And / or, the battery cell (200) further includes an adapter piece (400) disposed in the receiving cavity (101), the adapter piece (400) being connected to the tab assembly (210); the connecting piece (320) is disposed on the side of the lead-out wall (110) facing the receiving cavity (101), the piece body portion (311) is disposed on the side of the connecting piece (320) facing away from the receiving cavity (101), the piece body portion (311) being connected to the adapter piece (400), and the column portion (312) extending in a direction away from the receiving cavity (101).

8. The battery according to any one of claims 1-6, characterized in that, The outer contour of the insulating sealing connection layer (330) is elliptical. The major axis of the insulating sealing connection layer (330) is L1, and the minor axis of the insulating sealing connection layer (330) is L2. L1 ≥ 2.5 mm, and / or L2 ≥ 2 mm, and / or L1 / L2 ≥ 1.

1. Alternatively, the outer contour of the insulating sealing connection layer (330) is circular, and the outer diameter of the insulating sealing connection layer (330) is not less than 2 mm.

9. The battery according to any one of claims 1-6, characterized in that, The sheet portion (311) is located outside the receiving cavity (101), and the column portion (312) extends into the receiving cavity (101). The dimension of the column portion (312) extending beyond the surface of the lead-out wall (110) facing the receiving cavity (101) is L3, where 0.05mm≤L3≤0.2mm. And / or, in the radial direction of the pole assembly (300), the distance between the outer peripheral surface of the plate portion (311) and the outer peripheral surface of the connecting piece (320) is not greater than 0.2 mm; And / or, the diameter of the first through hole (111) is larger than the diameter of the second through hole (321); And / or, the distance between the outer peripheral surface of the column portion (312) and the inner peripheral surface of the first through hole (111) is H3, where H3 ≥ 0.1 mm; And / or, the thickness of the sheet portion (311) is D3, 0.15mm≤D3≤0.5mm; And / or, the insulating sealing connection layer (330) includes a first connection layer and a second connection layer, the first connection layer is connected to the sheet portion (311), the second connection layer is disposed between the first connection layer and the connection piece (320), the melting point of the first connection layer is T1, the melting point of the second connection layer is T2, 100℃≤T1≤150℃, 140℃≤T2≤190℃; And / or, the thickness of the insulating sealing connection layer (330) is D4, 0.02mm≤D4≤0.1mm.

10. The battery according to any one of claims 1-6, characterized in that, The housing (100) includes a shell portion (130) and a cover plate (600). The shell portion (130) has the lead-out wall surface (110) and a skirt (120). The skirt (120) is connected to the lead-out wall surface (110) and is located on the side of the lead-out wall surface (110) facing away from the receiving cavity (101). The cover plate (600) is connected to the skirt (120). The shell portion (130) and the cover plate (600) together define the receiving cavity (101). Wherein, the thickness of the skirt (120) is D5, and the thickness of the lead-out wall (110) is D6, where D5≤D6; And / or, the thickness of the skirt (120) is D5, 0.05mm≤D3≤0.15mm; And / or, the width of the skirt (120) is W3, 0.05mm≤W3≤0.3mm.

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