Battery

Abstract

The invention belongs to the technical field of batteries, and particularly discloses a battery which comprises a pole group, a cover plate assembly and a connecting piece. In the cover plate assembly, the pole penetrates through the cover plate body and the plastic part, the second connecting plate of the connecting piece is connected with the tab of the pole group, and the first connecting plate of the connecting piece is connected with the plate body part of the pole. The first connecting plate is detachably connected with the end face of the side, close to the pole group, of the plastic part through a fixing structure. Therefore, the first connecting plate and the plastic part can be stably fixed, the first connecting plate is prevented from being warped and unsmooth when the connecting piece is bent, and the problems that the tab is crushed and torn are solved. A convex hull is arranged on the first connecting plate and protrudes towards the side away from the plastic part in the first direction. The mechanical strength of the first connecting plate can be improved through the convex hulls, the first connecting plate is further prevented from being warped and unsmooth relative to the plastic part, meanwhile, the connecting piece can be prevented from being reversely mounted, burrs on the reverse side of the connecting piece are prevented from damaging the tab, and the reliability and safety of the battery are improved.

Description

Technical Field

[0001] This invention relates to the field of battery technology, and more particularly to a battery. Background Technology

[0002] Traditional quad-electrode prismatic lithium-ion battery structures have positive and negative electrode connecting tabs on the positive and negative electrode sides, respectively. One end of the positive electrode connecting tab is welded to the positive tabs of the two electrode groups, and the other end is welded to one of the electrode base plates on the cover plate assembly to form the positive electrode post on the outside of the cell. One end of the negative electrode connecting tab is welded to the negative tabs of the two electrode groups, and the other end is welded to the other electrode base plate on the cover plate assembly to form the negative electrode post on the outside of the cell.

[0003] Then, by bending the positive and negative electrode connecting pieces, the electrode assembly and the cover plate are brought together, and the electrode assembly is then inserted into the casing to complete the battery assembly. However, during the bending process of the positive and negative electrode connecting pieces, the surfaces of the positive and negative electrode connecting pieces near the cover plate assembly are easily pulled and bent, causing the welding surfaces of the positive electrode tab and the negative electrode tab to shift downwards. This compresses the bending space of the tabs, resulting in poor tab shape and a risk of short circuits when inserted backwards into the electrode assembly and contacting the electrode. Additionally, the sharp wrinkles caused by the pressure on the tabs can lead to tearing. Furthermore, the positive and negative electrode connecting pieces are designed symmetrically. During processing, stamping can create burrs on one edge of the positive and negative electrode connecting pieces. If the positive and negative electrode connecting pieces are installed backwards, the burr-covered surfaces will face the bending area of ​​the tabs, easily causing cuts to the tabs and reducing the battery's safety performance. Summary of the Invention

[0004] The purpose of this invention is to provide a battery that can prevent the connecting piece from warping or becoming uneven when bent, and the arrangement space of the tabs is not compressed, thus alleviating the risk of the tabs being crushed or torn. At the same time, the connecting piece is not easy to install backwards, avoiding damage to the tabs from burrs on the reverse side of the connecting piece, thereby improving the reliability of the battery.

[0005] To achieve this objective, the present invention adopts the following technical solution: This invention provides a battery, comprising: A pole assembly, one end of which is provided with a pole tab; A cover plate assembly includes a cover plate body, a plastic part, and an electrode post, wherein the plastic part is disposed on one side of the cover plate body along a first direction, and the electrode post passes through the cover plate body and the plastic part; The connecting piece includes a first connecting plate and a second connecting plate. The second connecting plate is connected to the electrode tab. The end of the first connecting plate away from the second connecting plate is connected to the plate body of the electrode post. The first connecting plate is detachably connected to the end face of the plastic part near the electrode assembly through a fixing structure. The first connecting plate is provided with a protrusion that protrudes along a first direction away from the plastic part.

[0006] Optionally, the fixing structure includes a positioning post and a positioning hole. The positioning post is connected to the end face of the plastic part away from the cover plate body. The positioning hole is provided at one end of the first connecting plate near the second connecting plate, and the positioning post passes through the positioning hole. Along the first direction, the end of the positioning post away from the plastic part forms an overlap by hot melting. The periphery of the overlap abuts against the first connecting plate circumferentially to the positioning hole to press the first connecting plate tightly against the plastic part.

[0007] Optionally, multiple positioning posts and positioning holes are provided, and each positioning post corresponds to a positioning hole. And / or, the convex hull is provided in multiple ways, and the convex hull is spaced apart from the positioning hole and arranged alternately.

[0008] Optionally, the number of convex hulls is N, the width of the convex hulls along the second direction is d, and the width of the first connecting plate along the second direction is y; The relationship between N, d, and y satisfies: 0.3 ≤ (N × d) / y ≤ 0.7; Where N is a positive integer; The range of values ​​for d is: 2mm≤d≤20mm.

[0009] Optionally, along the second direction, the distance between the convex hull near the side of the first connecting plate in the width direction and the adjacent side of the first connecting plate in the width direction is e; The value range of e is: 0.3mm≤e≤10mm; And / or, along the second direction, the distance between two adjacent convex hulls that are close to each other on one side is m; The value of m is in the range of 0.5mm ≤ m ≤ 10mm.

[0010] Optionally, the connecting piece includes a transition portion, with the first connecting plate and the second connecting plate respectively connected to both ends of the transition portion; the connecting piece is bent along the center line in the length direction of the transition portion, and the center line extends in a third direction so that the second connecting plate is parallel to the first connecting plate, and the connecting piece forms a bent section at the transition portion; Along the third direction, the distance between the edge of the convex hull away from the pole post and the bending segment is k; The value range of k is: 0.5mm≤k≤5mm.

[0011] Optionally, after the connecting piece is bent along the centerline of the length direction of the transition portion, the distance between the end face of the protrusion away from the plastic part and the end face of the second connecting plate away from the pole group in the first direction is g; The value of g is in the range of 0.1mm≤g≤3mm.

[0012] Optionally, after the connecting piece is bent along the centerline of the length direction of the transition portion, the distance between the end face of the protrusion away from the plastic part and the end face of the first connecting plate away from the pole group in the first direction is b, and the thickness of the first connecting plate is t. The relationship between b and t satisfies: 0.5mm 2 <b×t≤10mm 2 ; Where the value of b is in the range of: 0.25mm≤b≤5mm; The range of values ​​for t is: 0.5mm≤t≤2mm.

[0013] Optionally, the first connecting plate includes an electrical connection segment, an inclined segment, and a fixed segment connected in sequence. The electrical connection segment is attached to and connected to the plate body portion of the pole. The fixed segment is provided with the positioning hole and the protrusion. The inclined segment transitionally connects the electrical connection segment and the fixed segment. Along the first direction, there is a height difference between the electrical connection segment and the fixed segment. Wherein, along the third direction, the distance between the side of the inclined segment near the fixed segment and the side of the convex hull near the inclined segment is a; The range of values ​​for a is: 0.5mm ≤ a ≤ 10mm.

[0014] Optionally, along a third direction, the length of the convex hull is c, and the length of the fixed segment is x; The relationship between c and x satisfies: 0.4 ≤ c / x ≤ 0.8; Where x takes values ​​in the range of 5mm≤x≤20mm; The value range of c is: 2mm≤c≤16mm.

[0015] The beneficial effects of this invention are as follows: This invention provides a battery, including an electrode assembly, a cover plate assembly, and a connecting piece. The cover plate assembly includes a cover plate body, a plastic part, and an electrode post. The electrode post passes through the cover plate body and the plastic part. The connecting piece includes a first connecting plate and a second connecting plate. The second connecting plate is connected to the electrode tab of the electrode assembly, and the end of the first connecting plate away from the second connecting plate is connected to the plate body portion of the electrode post. The first connecting plate and the end face of the plastic part near the electrode assembly are detachably connected by a fixing structure. The fixing structure stably fixes the first connecting plate and the plastic part, minimizing the risk of the first connecting plate warping or becoming uneven relative to the plastic part when the connecting piece is bent. It also provides ample space for the electrode tab, mitigating the problems of pressure damage and tearing of the electrode tab. Simultaneously, the first connecting plate has a protrusion that protrudes along a first direction towards the side away from the plastic part. The protrusion design increases the mechanical strength of the first connecting plate, ensuring that the first connecting plate will not warp or become uneven relative to the plastic part when the connecting piece is bent. Furthermore, the protrusion design also prevents the connecting piece from being installed backwards, preventing burrs on the reverse side of the connecting piece from damaging the tabs, thus improving the reliability and safety of the battery. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the content of the embodiments of the present invention and these drawings without creative effort.

[0017] Figure 1 This is a cross-sectional view of the connecting piece and cover plate assembly and the electrode assembly in the prior art. Figure 2 This is a bottom view of the connecting piece and cover plate assembly provided in Embodiment 1 of the present invention after assembly; Figure 3 This is a side view of the connecting piece and cover plate assembly provided in Embodiment 1 of the present invention after assembly; Figure 4 for Figure 3 Sectional view of section II-II; Figure 5 This is a top view of the connecting piece (before bending) provided in Embodiment 1 of the present invention; Figure 6 This is a side view of the connecting piece (before bending) provided in Embodiment 1 of the present invention; Figure 7 This is a cross-sectional view of the connecting piece and cover plate assembly and the electrode assembly provided in Embodiment 1 of the present invention after assembly; Figure 8 for Figure 7 Enlarged view of a section at point III; Figure 9This is a schematic diagram of the connecting piece (before bending) provided in Embodiment 2 of the present invention; Figure 10 This is a cross-sectional view of the connecting piece and cover plate assembly and the electrode assembly provided in Embodiment 2 of the present invention.

[0018] In the picture: 10' Connecting tab; 11' Pin; 20' Cover plate assembly; 30' Electrode group; 31' Electrode tab; 100. Cover plate assembly; 110. Cover plate body; 120. Plastic part; 121. Positioning post; 1211. Overlapping part; 122. Limiting flange; 1221. Limiting groove; 130. Pole post; 131. Plate part; 132. Pillar part; 200. Connecting piece; 210. First connecting plate; 211. Electrical connection section; 212. Inclined section; 213. Fixing section; 2131. Positioning hole; 2132. Protrusion; 220. Second connecting plate; 221. Pin; 230. Bending section; 240. Transition part; 241. Through hole; 300. Pole group; 310. Pole tab. Detailed Implementation

[0019] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0020] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication 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 invention based on the specific circumstances.

[0021] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0022] In the description of this embodiment, the terms "upper," "lower," "left," and "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention. In addition, the terms "first" and "second" are used only for distinction in description and have no special meaning.

[0023] like Figure 1 As shown, in the prior art, the two pins 11' of each connecting piece 10' are welded to the tabs 31' of the two pole groups 30' respectively. The other end of the connecting piece 10' is bent and connected to the pole integrated on the cover plate assembly 20', thereby allowing the electrical energy of the pole group 30' to be conducted through the pole. However, during the bending process of the connecting piece 10', the end of the connecting piece 10' connected to the pole is easily bent due to the lack of fixation, causing the welding surface of the tab 31' and the pin 11' to shift downward, compressing the arrangement space of the tab 31', resulting in a poor shape of the tab 31'. The tab 31' has the risk of being pressed into the pole group 30', causing a short circuit, and also increases the risk of wrinkles and tearing after being pressed. In addition, since the connecting piece 10' is often designed as a planar structure, the two connecting pieces 10' connected to the same pole have the same shape, making it very easy to install the two connecting pieces 10' backwards. During the manufacturing process of connecting piece 10', after stamping and blanking, there will be metal burrs on the reverse contour boundary of connecting piece 10'. If connecting piece 10' is installed backwards, the metal burrs on the reverse contour boundary of connecting piece 10' will come into contact with the bent part of tab 31'. Figure 1 The location indicated by mark I in the middle can easily cause the tab 31' to break, which in turn leads to battery failure.

[0024] Example 1 This embodiment provides a battery that can solve the above-mentioned problems.

[0025] Specifically, see Figures 2-6 The battery includes an electrode assembly 300, a cover plate assembly 100, and a connecting piece 200. One end of the electrode assembly 300 has a tab 310. The cover plate assembly 100 includes a cover plate body 110, a plastic part 120, and a terminal post 130. The plastic part 120 is disposed on the side of the cover plate body 110 near the electrode assembly 300 along a first direction and is attached to the cover plate body 110. The first direction is... Figure 2The X-axis direction is shown in the diagram. The terminal post 130 passes through the cover plate body 110 and the plastic part 120, and is fixed to both. The connecting piece 200 is used to electrically connect the tab 310 of the electrode assembly 300 and the plate portion 131 of the terminal post 130, thereby enabling the discharge of internal battery current. The post portion 132 of the terminal post 130 is located on the side of the plastic part 120 opposite to the electrode assembly 300, and is used to connect to the external circuitry of the battery. The connecting piece 200 includes a first connecting plate 210 and a second connecting plate 220. The second connecting plate 220 is connected to the tab 310, and the end of the first connecting plate 210 away from the second connecting plate 220 is connected to the plate portion 131 of the terminal post 130. The first connecting plate 210 is detachably connected to the end face of the plastic part 120 near the electrode assembly 300 via a fixing structure. Therefore, the positions of the first connecting plate 210 and the plastic part 120 are relatively fixed. When the second connecting plate 220 is bent relative to the first connecting plate 210, the first connecting plate 210 will not be pulled and will not lift up towards the side where the electrode group 300 is located. The first connecting plate 210 can remain flat, avoiding the compression of the arrangement space of the electrode tab 310. The electrode tab 310 is not easy to be inserted backward into the electrode group 300 and cause a short circuit, and is not easy to cause risks such as crushing, wrinkling and tearing.

[0026] Furthermore, the first connecting plate 210 is provided with a protrusion 2132. In some embodiments, the protrusion 2132 can be formed by stamping the first connecting plate 210. The protrusion 2132 protrudes along the first direction away from the plastic part 120. The protrusion 2132 serves to prevent incorrect installation, thus protecting the tab 310 and preventing metal burrs on the reverse side of the connecting piece 200 from damaging the tab 310, which is beneficial to improving the reliability of the battery. It should be noted that those skilled in the art should arrange the position of the protrusion 2132 and the fixing structure reasonably to avoid interference. The second connecting plate 220 includes two pins 221, which are respectively connected to the tab 310 of one electrode group 300, thereby connecting the positive or negative electrodes of the two electrode groups 300 in parallel.

[0027] See Figure 5 , Figure 7 and Figure 8In this embodiment, the fixing structure for connecting the first connecting plate 210 and the plastic part 120 includes a positioning post 121 and a positioning hole 2131. The positioning post 121 is connected to the end face of the plastic part 120 facing away from the cover plate body 110. The first connecting plate 210 has a positioning hole 2131 at one end near the second connecting plate 220 (described in the state when the connecting piece 200 is not bent), and the positioning post 121 passes through the positioning hole 2131. Along the first direction, the end of the positioning post 121 away from the plastic part 120 forms an overlap portion 1211 through heat fusion. The periphery of the overlap portion 1211 abuts against the first connecting plate 210 circumferentially around the positioning hole 2131, thereby pressing the first connecting plate 210 tightly against the plastic part 120. The cooperation between the positioning post 121 and the positioning hole 2131 ensures accurate positioning between the plastic part 120 and the connecting piece 200. The positioning post 121 limits the connection piece 200, preventing it from shifting or tilting during battery use. This also prevents the connection piece 200 from overlapping with the casing, thus avoiding short circuits and ensuring good battery safety. Furthermore, the end of the positioning post 121 furthest from the plastic part 120 forms an overlap portion 1211. This overlap portion 1211 stably fixes the first connecting plate 210 of the connecting piece 200 to the plastic part 120, improving the stability of the connecting piece 200 installation and preventing the first connecting plate 210 from warping towards the electrode group 300 when the connecting piece 200 is bent. Simultaneously, the protrusion 2132 strengthens the structural strength of the first connecting plate 210, making it less prone to warping.

[0028] See also Figure 5 In this embodiment, multiple positioning posts 121 and positioning holes 2131 are provided. For example, two positioning posts 121 and two positioning holes 2131 can be provided, with the two positioning holes 2131 arranged at intervals along the second direction on the first connecting plate 210. The two positioning posts 121 are arranged at intervals along the second direction on the end face of the plastic part 120 facing the pole group 300, and the positioning posts 121 and positioning holes 2131 correspond one-to-one.

[0029] Furthermore, multiple protrusions 2132 are provided, and the protrusions 2132 and positioning holes 2131 are spaced apart and alternately arranged. For example, in this embodiment, two protrusions 2132 are also provided, one of which is located between two positioning holes 2131, and the other protrusion 2132 is located on the side of the first connecting plate 210 in the width direction (second direction).

[0030] Optionally, the number of convex hulls 2132 is N (N is a positive integer), the width of the convex hulls 2132 along the second direction is d, and the width of the first connecting plate 210 along the second direction is y. The relationship between N, d, and y satisfies: 0.3 ≤ (N×d) / y ≤ 0.7. In this embodiment, the number of convex hulls 2132 is 2, that is, 0.3 ≤ 2d / y ≤ 0.7. For example, the value of (N×d) / y can be 0.3, 0.4, 0.5, 0.6, or 0.7. Of course, in other embodiments, the value of (N×d) / y can also be other values ​​in the range of 0.3-0.7, and is not limited to the examples above. Understandably, the value of (N×d) / y should not be too small, otherwise the reinforcing effect of the convex hull 2132 on the first connecting plate 210 of the connecting piece 200 will not be obvious, and the phenomenon of deformation and collapse of the first connecting plate 210 after the connecting piece 200 is bent will still be quite obvious. Of course, the value of (N×d) / y should not be too large either, otherwise the arrangement space of the convex hull 2132 will be insufficient, and the bending position of the convex hull 2132 and the connecting piece 200 will be too close, affecting the processing and bending operation of the connecting piece 200.

[0031] Furthermore, the value of d ranges from 2mm to 20mm. For example, the value of d can be 2mm, 5mm, 8mm, 10mm, 12mm, 15mm, 18mm, or 20mm, etc. Of course, the value of d can also be other values ​​within the range of 2mm to 20mm, and is not limited to the examples above. It should be noted that the value of d should not be too small, otherwise the size of the contour punch used to process the protrusion 2132 will be too small, which may easily lead to the stamping breakage and wear of the first connecting plate 210; the value of d should also not be too large, otherwise, the arrangement space required for the protrusion 2132 will be insufficient.

[0032] In this embodiment, the value of d is controlled between 2mm and 20mm, and the value of (N×d) / y is controlled between 0.3 and 0.7. This allows for a relatively large size of the contour punch used to process the protrusion 2132, ensuring high structural strength of the first connecting plate 210 of the connecting piece 200 after processing. This prevents the first connecting plate 210 from warping or becoming uneven relative to the plastic part 120 during bending of the connecting piece 200, thus avoiding downward compression of the bending space of the tab 310 and preventing damage or tearing of the tab 310. This is beneficial for the manufacturing and bending operation of the connecting piece 200, improving the manufacturing yield of the connecting piece 200 and the battery.

[0033] See also Figure 5 Along the second direction, the distance between the protrusion 2132 near the side of the first connecting plate 210 in the width direction and the adjacent side of the first connecting plate 210 in the width direction is e, and the value of e ranges from 0.3mm ≤ e ≤ 10mm. The aforementioned second direction is... Figure 5The Y-axis direction is shown in the figure. For example, the value of e can be 0.3mm, 0.5mm, 1mm, 2mm, 3mm, 4mm, 5mm, 8mm, or 10mm, etc. Of course, the value of e can also be other values ​​within the range of 0.3mm-10mm, and is not limited to the examples above. Further, along the second direction, the distance between the two adjacent convex hulls 2132 on the side closest to each other is m, and the value of m is in the range of 0.5mm≤m≤10mm. For example, the value of m can be 0.5mm, 0.8mm, 1mm, 2mm, 3mm, 4mm, 5mm, 8mm, or 10mm, etc. Of course, the value of m can also be other values ​​within the range of 0.5mm-10mm, and is not limited to the examples above.

[0034] Understandably, if the values ​​of e and m are too small, it will be difficult to stamp the protrusion 2132; if the values ​​of e and m are too large, it will limit the reinforcing effect of the protrusion 2132 on the first connecting plate 210, and the first connecting plate 210 will easily deform and collapse after the connecting piece 200 is bent. In this embodiment, the value of e is controlled between 0.3mm and 10mm, and the value of m is controlled between 0.5mm and 10mm. This facilitates the stamping of the protrusion 2132 and ensures that the first connecting plate 210 has high strength. This avoids the first connecting plate 210 from warping and becoming uneven when the connecting piece 200 is bent, and avoids the downward compression of the electrode tab 310 space, thus preventing the electrode tab 310 from being crushed and torn.

[0035] See also Figures 4-6 In this embodiment, the connecting piece 200 includes a transition portion 240, with its two ends connected to a first connecting plate 210 and a second connecting plate 220, respectively. The connecting piece 200 is bent along the centerline of the transition portion 240's length direction, with the centerline extending in a third direction, so that the second connecting plate 220 is parallel to the first connecting plate 210. The connecting piece 200 forms a bent section 230 at the transition portion 240. Furthermore, to make the connecting piece 200 easier to bend, at least one through hole 241 is provided on the transition portion 240, located on the centerline of the transition portion 240's length direction. This makes the connecting piece 200 easier to bend and ensures that the bent connecting piece 200 has a good shape, preventing short circuits with the housing. In this embodiment, only one through hole 241 is provided. In other embodiments, depending on the size of the connecting piece 200, multiple through holes 241 can be provided as needed, with the multiple through holes 241 spaced apart along the centerline of the transition portion 240's length direction.

[0036] Along the third direction, the distance between the edge of the convex hull 2132 away from the pole post 130 and the bending segment 230 is k, and the value of k ranges from 0.5mm to 5mm. The aforementioned third direction is... Figure 4The Z-axis direction is shown in the figure. For example, the value of k can be 0.5mm, 0.8mm, 1mm, 2mm, 3mm, 4mm, or 5mm, etc. Of course, the value of k can also be other values ​​in the range of 0.5mm-5mm, and is not limited to the examples above. It is understandable that if the value of k is too small, it will affect the bending of the connecting piece 200 along the center line of the transition portion 240, which may lead to a poor state of the connecting piece 200 after bending. The bent section 230 is prone to short circuit in the housing. At the same time, due to the displacement of the position of the bent section 230, it may also pull on the tab 310 and cause the tab 310 to tear. If the value of k is too large, the reinforcing effect of the protrusion 2132 on the first connecting plate 210 of the connecting piece 200 will not be obvious. After the connecting piece 200 is bent along the center line of the transition portion 240, the first connecting plate 210 will also have the phenomenon of bending deformation and collapse. In this embodiment, the value of k is controlled between 0.5mm and 5mm. This ensures that the connecting piece 200 bends along the set bending line (i.e., the center line in the length direction of the transition portion 240), improving the accuracy of the position and shape of the connecting piece 200 after bending, ensuring the good shape of the tab 310, reducing the risk of the tab 310 tearing, and also ensuring that the convex 2132 has a significant reinforcing effect on the first connecting plate 210 of the connecting piece 200, preventing the first connecting plate 210 from bending, deforming, and collapsing after the connecting piece 200 is bent.

[0037] Furthermore, after the connecting piece 200 is bent along the centerline of the transition portion 240, the distance between the end face of the protrusion 2132 away from the plastic part 120 and the end face of the second connecting plate 220 away from the electrode assembly 300 along the first direction is g, and the value of g is in the range of 0.1mm ≤ g ≤ 3mm. For example, the value of g can be 0.1mm, 0.3mm, 0.5mm, 0.8mm, 1mm, 2mm, or 3mm. Of course, the value of g can also be other values ​​in the range of 0.1mm-3mm, and is not limited to the above examples. It is understandable that if the value of g is too small, interference between the protrusion 2132 and the second connecting plate 220 may occur when the connecting piece 200 is bent along the centerline of the transition portion 240, which may cause metal shavings to fall into the battery and cause a short circuit risk; if the value of g is too large, the height of the protrusion 2132 along the first direction is severely limited, and the reinforcing effect of the protrusion 2132 on the first connecting plate 210 is not obvious. In this embodiment, by controlling the value of g within the range of 0.1mm-3mm, it is possible to avoid interference between the protrusion 2132 and the second connecting plate 220 when the connecting piece 200 is bent, thereby reducing the risk of internal short circuit in the battery. At the same time, it is possible to ensure the reinforcing effect of the protrusion 2132 on the first connecting plate 210, thereby preventing the first connecting plate 210 from bending, deforming, and collapsing after the connecting piece 200 is bent.

[0038] Optionally, after the connecting piece 200 is bent along the centerline of the transition portion 240, the distance between the end face of the protrusion 2132 away from the plastic part 120 and the end face of the first connecting plate 210 away from the electrode assembly 300 in the first direction is b, and the thickness of the first connecting plate 210 is t. The thickness of the second connecting plate 220 is equal to the thickness of the first connecting plate 210. The relationship between b and t satisfies: 0.5mm. 2 <b×t≤10mm 2 For example, the value of b×t can be 0.5mm. 2 0.7mm 2 1mm 2 2mm 2 3mm 2 4mm 2 5mm 2 8mm 2 or 10mm 2 Of course, in other embodiments, the value of b×t can also be other values ​​within the above range, and is not limited to the examples above. By controlling the value of b×t within the above range, it can be ensured that the convex hull 2132 provides good reinforcement to the first connecting plate 210 of the connecting piece 200, avoiding the problem of the first connecting plate 210 warping or becoming uneven when the connecting piece 200 is bent; at the same time, it facilitates the bending and processing of the connecting piece 200, avoids interference problems, and improves the compactness of the connecting piece 200 structure, which is beneficial to improving the energy density of the battery.

[0039] Optionally, the range of values ​​for b is 0.25mm ≤ b ≤ 5mm, and the range of values ​​for t is 0.5mm ≤ t ≤ 2mm. For example, when the value of b is 0.25mm, the value of t can be 2mm. When the value of b is 1mm, the value of t can be 0.5mm, 0.7mm, 1mm, or 2mm, etc. When the value of b is 2mm, the value of t can be 0.5mm, 0.7mm, 1mm, or 2mm, etc. When the value of b is 5mm, the value of t can be 0.5mm, 0.7mm, 1mm, 1.5mm, or 2mm, etc.

[0040] See also Figures 4-6In this embodiment, a limiting flange 122 is provided on the end face of the plastic part 120 facing the electrode assembly 300. The limiting flange 122 and the end face of the plastic part 120 facing the electrode assembly 300 form a limiting groove 1221, and the plate portion 131 of the electrode post 130 is at least partially accommodated in the limiting groove 1221. Through the cooperation of the limiting groove 1221 and the plate portion 131, precise positioning between the electrode post 130, the cover plate body 110, and the plastic part 120 can be achieved. At the same time, since the plate portion 131 protrudes from the end face of the plastic part 120 facing the electrode assembly 300, the first connecting plate 210 can make stable and reliable contact with the plate portion 131. The specific structure of the first connecting plate 210 adopts the following scheme.

[0041] Specifically, in this embodiment, the first connecting plate 210 includes an electrical connecting segment 211, an inclined segment 212, and a fixed segment 213 connected in sequence. The electrical connecting segment 211 is attached to and connected to the plate body portion 131 of the pole post 130. The fixed segment 213 is provided with a positioning hole 2131 and a protrusion 2132. The inclined segment 212 transitionally connects the electrical connecting segment 211 and the fixed segment 213, allowing for a smooth transition between the two segments. Along the first direction, there is a height difference between the electrical connecting segment 211 and the fixed segment 213. Therefore, the first connecting plate 210 can adaptively cooperate with the plate body portion 131 of the pole post 130, ensuring that the fixed segment 213 can be attached to and connected to the plate body portion 131.

[0042] Optionally, along the third direction, the distance between the side of the inclined segment 212 near the fixed segment 213 and the side of the protrusion 2132 near the inclined segment 212 is denoted as 'a', and the value of 'a' ranges from 0.5mm to 10mm. For example, the value of 'a' can be 0.5mm, 1mm, 2mm, 3mm, 4mm, 5mm, 8mm, or 10mm. Of course, the value of 'a' can also be other values ​​within the above range, and is not limited to the examples mentioned above. It is understandable that if the value of 'a' is too small, the protrusion 2132 on the first connecting plate 210 of the connecting piece 200 cannot be stamped; while if the value of 'a' is too large, it will limit the length of the protrusion 2132 along the third direction, which is not conducive to strengthening the strength of the first connecting plate 210, and the phenomenon of bending deformation and collapse of the first connecting plate 210 after the connecting piece 200 is bent is still quite obvious. In this embodiment, the value of a is controlled between 0.5mm and 10mm, which not only facilitates the processing and manufacturing of the connecting piece 200, but also ensures that the convex 2132 has sufficient size to improve the strength of the connecting piece 200. This prevents the first connecting plate 210 from warping or becoming uneven when the connecting piece 200 is bent, which would cause the first connecting plate 210 to tilt downward and compress the space of the tab 310, resulting in damage and tearing of the tab 310.

[0043] Furthermore, along the third direction, the length of the convex hull 2132 is c, and the length of the fixed segment 213 is x. The relationship between c and x satisfies: 0.4 ≤ c / x ≤ 0.8. For example, the value of c / x can be 0.4, 0.5, 0.6, 0.7, or 0.8. Of course, the value of c / x can also be other values ​​within the above range, and is not limited to the examples above. By controlling the value of c / x within the above range, it is possible to ensure the reinforcing effect of the convex hull 2132 on the first connecting plate 210, preventing the first connecting plate 210 from bending and collapsing after the connecting piece 200 is bent, and also to facilitate the manufacturing and bending of the connecting piece 200, thereby improving the manufacturing yield of the connecting piece 200 and the battery. Understandably, if the value of c / x is too small, the reinforcing effect of the convex hull 2132 on the first connecting plate 210 is not obvious, and the phenomenon of bending deformation and collapse of the first connecting plate 210 after the connecting piece 200 is bent is still quite obvious; if the value of c / x is too large, the arrangement space is insufficient, and the distance between the convex hull 2132 and the inclined section 212 and the bending section 230 is too close, which affects the yield rate of the connecting piece 200 and the accuracy of the shape of the connecting piece 200 after bending.

[0044] Optionally, the range of x is 5mm ≤ x ≤ 20mm, and the range of c is 2mm ≤ c ≤ 16mm. For example, when the value of x is 5mm, the value of c can be 2mm, 3mm, or 4mm, etc. When the value of x is 10mm, the value of c can be 4mm, 5mm, 6mm, or 8mm, etc. When the value of x is 20mm, the value of c can be 8mm, 9mm, 10mm, 12mm, or 16mm, etc.

[0045] The following uses samples from specific implementation cases to verify the values ​​of the relevant dimensional parameters b, t, b×t, c, x, c / x, and (N×d) / y of the battery. See Table 1 for details.

[0046] Table 1 In Examples 1-4, the values ​​of b, t, b×t, c, x, c / x, and (N×d) / y all meet their corresponding size constraints. The positioning post 121 and the positioning hole 2131 on the connecting piece 200 can be smoothly installed together. After installation, the connecting piece 200 is not easy to slip off the connecting post. The positioning post 121 has a good limiting effect on the connecting piece 200. After the connecting piece 200 is bent, the first connecting plate 210 does not bend, deform, or collapse. The connecting piece 200 and the tab 310 are in good shape and there is no short circuit problem. After the battery is vibrated, the tab 310 does not tear. The battery product is in good condition.

[0047] In Comparative Examples 1 and 2, the value of b×t is less than the minimum value of 0.5mm2 < b×t ≤ 10mm2. The reinforcement effect of the convex bulge 2132 on the first connecting plate 210 is insufficient. After the connecting piece 200 is bent, the first connecting plate 210 is bent, deformed and collapsed. The arrangement space of the tab 310 is compressed. The shape of the connecting piece 200 and the tab 310 is not good, which poses a short circuit risk and reduces the safety of the battery. Furthermore, after the battery is subjected to vibration test, the tab 310 is accompanied by tearing problem, resulting in a defective battery product.

[0048] In Comparative Example 3, the value of c / x is less than the minimum value of 0.4 ≤ c / x ≤ 0.8. After setting the convex bulge 2132, the mechanical strength of the first connecting plate 210 of the connecting piece 200 is insufficient. After the connecting piece 200 is bent, the first connecting plate 210 is bent and deformed and collapses, the arrangement space of the tab 310 is compressed, the shape of the connecting piece 200 and the tab 310 is not good, there is a risk of short circuit, the safety of the battery is reduced, and after the battery is subjected to vibration test, the tab 310 is accompanied by tearing problem, resulting in a defective battery product.

[0049] In Comparative Example 4, the value of (N×d) / y is less than the minimum value of 0.3≤(N×d) / y≤0.7. After setting the convex bulge 2132, the mechanical strength of the first connecting plate 210 of the connecting piece 200 is insufficient. After the connecting piece 200 is bent, the first connecting plate 210 is bent and deformed and collapses, the arrangement space of the tab 310 is compressed, the shape of the connecting piece 200 and the tab 310 is not good, there is a risk of short circuit, the safety of the battery is reduced, and after the battery is vibrated, the tab 310 is accompanied by tearing problem, resulting in a defective battery product.

[0050] In summary, when all the above parameters meet their corresponding size limitations, the positioning post 121 can be smoothly assembled with the positioning hole 2131 on the connecting piece 200, providing a good limiting effect on the connecting piece 200. This allows the first connecting plate 210 of the connecting piece 200 to be stably fixed on the plastic part 120. At the same time, the first connecting plate 210 with the protrusion 2132 has high mechanical strength. After the connecting piece 200 is bent, the first connecting plate 210 will not be pulled and bend towards the side where the electrode group 300 is located, providing ample bending space for the electrode tab 310. This ensures that the connecting piece 200 and the electrode tab 310 have good shape inside the housing, avoiding the risk of short circuits and tearing of the electrode tab 310.

[0051] Example 2 This embodiment provides a battery that differs from the battery in Embodiment 1 in that the specific structure of the connecting piece 200 is slightly different.

[0052] See Figure 9 and Figure 10In this embodiment, the first connecting plate 210 of the connecting piece 200 includes an electrical connecting section 211 and a fixing section 213 connected in sequence. The electrical connecting section 211 is attached to and connected to the plate body portion 131 of the pole post 130. The fixing section 213 is provided with a positioning hole 2131 and a protrusion 2132. The electrical connecting section 211 and the fixing section 213 are located in the same plane and have a smooth transition. The connecting piece 200 in this embodiment is suitable for situations where the end face of the plate body portion 131 of the pole post 130 facing the pole group 300 is flush with the end face of the plastic part 120 facing the pole group 300, or where the end face of the plate body portion 131 of the pole post 130 facing the pole group 300 does not significantly protrude from the end face of the plastic part 120 facing the pole group 300. At this time, no limiting flange 122 is provided on the end face of the plastic part 120 facing the pole group 300. The first connecting plate 210 can also adaptably cooperate with the plate body 131 of the pole post 130 to ensure that the fixing section 213 can be attached to and welded to the plate body 131.

[0053] The remaining structures in this embodiment are the same as those in Embodiment 1, and will not be described again here.

[0054] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art will be able to make various obvious changes, readjustments, and substitutions without departing from the scope of protection of the present invention. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A battery, characterized in that, include: A pole assembly, one end of which is provided with a pole tab; A cover plate assembly includes a cover plate body, a plastic part, and an electrode post, wherein the plastic part is disposed on one side of the cover plate body along a first direction, and the electrode post passes through the cover plate body and the plastic part; The connecting piece includes a first connecting plate and a second connecting plate. The second connecting plate is connected to the electrode tab. The end of the first connecting plate away from the second connecting plate is connected to the plate body of the electrode post. The first connecting plate is detachably connected to the end face of the plastic part near the electrode assembly through a fixing structure. The first connecting plate is provided with a protrusion that protrudes along a first direction away from the plastic part.

2. The battery according to claim 1, characterized in that, The fixing structure includes a positioning post and a positioning hole. The positioning post is connected to the end face of the plastic part away from the cover plate body. The positioning hole is provided at one end of the first connecting plate near the second connecting plate, and the positioning post passes through the positioning hole. Along the first direction, the end of the positioning post away from the plastic part forms an overlap by hot melting. The periphery of the overlap abuts against the first connecting plate circumferentially to the positioning hole to press the first connecting plate tightly against the plastic part.

3. The battery according to claim 2, characterized in that, Multiple positioning posts and positioning holes are provided, and each positioning post corresponds to a positioning hole. And / or, the convex hull is provided in multiple ways, and the convex hull is spaced apart from the positioning hole and arranged alternately.

4. The battery according to claim 3, characterized in that, The number of convex hulls is N, the width of the convex hulls along the second direction is d, and the width of the first connecting plate along the second direction is y; The relationship between N, d, and y satisfies: 0.3 ≤ (N × d) / y ≤ 0.7; Where N is a positive integer; The range of values ​​for d is: 2mm≤d≤20mm.

5. The battery according to claim 3, characterized in that, Along the second direction, the distance between the convex hull near the side of the first connecting plate in the width direction and the adjacent side of the first connecting plate in the width direction is e; The value range of e is: 0.3mm≤e≤10mm; And / or, along the second direction, the distance between two adjacent convex hulls that are close to each other on one side is m; The value of m is in the range of 0.5mm ≤ m ≤ 10mm.

6. The battery according to claim 1, characterized in that, The connecting piece includes a transition portion, with the first connecting plate and the second connecting plate respectively connected to its two ends; the connecting piece is bent along the center line of the length direction of the transition portion, and the center line extends along a third direction to make the second connecting plate parallel to the first connecting plate, and the connecting piece forms a bent section at the transition portion; Along the third direction, the distance between the edge of the convex hull away from the pole post and the bending segment is k; The value range of k is: 0.5mm≤k≤5mm.

7. The battery according to claim 6, characterized in that, After the connecting piece is bent along the centerline of the length direction of the transition portion, the distance between the end face of the protrusion away from the plastic part and the end face of the second connecting plate away from the pole group in the first direction is g; The value of g is in the range of 0.1mm≤g≤3mm.

8. The battery according to claim 6, characterized in that, After the connecting piece is bent along the centerline of the length direction of the transition portion, the distance between the end face of the protrusion away from the plastic part and the end face of the first connecting plate away from the pole group is b in the first direction, and the thickness of the first connecting plate is t. The relationship between b and t satisfies: 0.5mm 2 <b×t≤10mm 2 ; Where the value of b is in the range of: 0.25mm≤b≤5mm; The range of values ​​for t is: 0.5mm≤t≤2mm.

9. The battery according to claim 2, characterized in that, The first connecting plate includes an electrical connection segment, an inclined segment, and a fixed segment connected in sequence. The electrical connection segment is attached to and connected to the plate body portion of the pole post. The fixed segment is provided with the positioning hole and the protrusion. The inclined segment transitionally connects the electrical connection segment and the fixed segment. Along the first direction, there is a height difference between the electrical connection segment and the fixed segment. Wherein, along the third direction, the distance between the side of the inclined segment near the fixed segment and the side of the convex hull near the inclined segment is a; The range of values ​​for a is: 0.5mm ≤ a ≤ 10mm.

10. The battery according to claim 9, characterized in that, Along the third direction, the length of the convex hull is c, and the length of the fixed segment is x; The relationship between c and x satisfies: 0.4 ≤ c / x ≤ 0.8; Where x takes values ​​in the range of 5mm≤x≤20mm; The value range of c is: 2mm≤c≤16mm.

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