Pole piece connecting assembly and battery

Abstract

The utility model relates to a pole piece connecting assembly and a battery, a pole piece assembly in the pole piece connecting assembly comprises at least one positive pole piece and at least one negative pole piece, at least two side edges of the positive pole piece are provided with first tabs, and at least two side edges of the negative pole piece are provided with second tabs; the pin assembly comprises a first pin piece and a second pin piece, the first pin piece is connected with the first tabs of the corresponding positive pole piece, and the second pin piece is connected with the second tabs of the corresponding negative pole piece. The first tabs are respectively arranged on at least two side edges of the positive pole piece and are respectively connected with the first tabs through the first pin pieces, so that the current on the positive pole piece is uniformly distributed, the second tabs are respectively arranged on at least two side edges of the negative pole piece and are respectively connected with the second tabs through the second pin pieces, and the current on the negative pole piece is uniformly distributed. And thus, the current on the negative pole piece is uniformly distributed, and the internal resistance of the battery is reduced.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a pole piece connection assembly and a battery. Background Art

[0002] With the widespread adoption of batteries in new energy vehicles, energy storage power stations, and other applications, the demand for battery systems is growing. Increasing the size and capacity of individual batteries can reduce the number of batteries required in a battery system. Larger batteries with higher capacity have become an industry trend. However, larger batteries increase the current path, increasing internal resistance and potentially causing overheating.

[0003] Existing large-size, large-capacity batteries usually reduce the internal resistance of the battery by adding poles or multiple sets of positive and negative plates, but the above methods still lead to high internal resistance of the battery and uneven current distribution. Utility Model Content

[0004] Based on this, a pole piece connection assembly and a battery are provided.

[0005] In a first aspect, the present application provides a pole piece connection assembly, comprising:

[0006] A pole piece assembly, the pole piece assembly comprising at least one positive pole piece and at least one negative pole piece, at least two sides of the positive pole piece are provided with a first pole tab, and at least two sides of the negative pole piece are provided with a second pole tab;

[0007] The pin assembly includes a first pin component and a second pin component. The first pin components are respectively connected to the first tabs of the corresponding positive electrode sheets, and the second pin components are respectively connected to the second tabs of the corresponding negative electrode sheets.

[0008] In one embodiment, the positive electrode plate has a first side and a second side adjacent to each other, and the first electrode tab includes a first sub-electrode tab and a second sub-electrode tab; the first side of the positive electrode plate is provided with the first sub-electrode tab, the second side of the positive electrode plate is provided with the second sub-electrode tab, and the first pin connects the first sub-electrode tab and the second sub-electrode tab;

[0009] The negative electrode plate has an adjacent first side and a second side, and the second electrode tab includes a third sub-pole tab and a fourth sub-pole tab; the first side of the negative electrode plate is provided with a third sub-pole tab, the second side of the negative electrode plate is provided with a fourth sub-pole tab, and the second pin member connects the third sub-pole tab and the fourth sub-pole tab.

[0010] In one embodiment, the first sub-tab is provided with a first pre-welding area, the second sub-tab is provided with a second pre-welding area, the third sub-tab is provided with a third pre-welding area, and the fourth sub-tab is provided with a fourth pre-welding area;

[0011] The first end of the first pin is arranged in the first pre-welding area, and the second end of the first pin is arranged in the second pre-welding area; the first end of the second pin is arranged in the third pre-welding area, and the second end of the second pin is arranged in the fourth pre-welding area.

[0012] In one embodiment, a first final welding area is provided in the first pre-welding area, a second final welding area is provided in the second pre-welding area, a third final welding area is provided in the third pre-welding area, and a fourth final welding area is provided in the fourth pre-welding area;

[0013] The first end of the first pin is connected to the first terminal welding area, and the second end of the first pin is connected to the second terminal welding area; the first end of the second pin is connected to the third terminal welding area, and the second end of the second pin is connected to the fourth terminal welding area;

[0014] The area of ​​the first pre-welding region is larger than that of the first final welding region, the area of ​​the second pre-welding region is larger than that of the second final welding region, the area of ​​the third pre-welding region is larger than that of the third final welding region, and the area of ​​the fourth pre-welding region is larger than that of the fourth final welding region.

[0015] In one embodiment, the area ratio of the first pre-welding region to the first final welding region is 1.8:1 to 2.2:1, the area ratio of the second pre-welding region to the second final welding region is 1.8:1 to 2.2:1, the area ratio of the third pre-welding region to the third final welding region is 1.8:1 to 2.2:1, and the area ratio of the fourth pre-welding region to the fourth final welding region is 1.8:1 to 2.2:1.

[0016] In one embodiment, the first pre-welding region is disposed near a bottom edge of the first sub-tab, where the bottom edge of the first sub-tab is a side away from the second sub-tab; the second pre-welding region is disposed near a bottom edge of the second sub-tab, where the bottom edge of the second sub-tab is a side away from the first sub-tab;

[0017] The third pre-welding area is arranged near the bottom edge of the third sub-pole lug, and the bottom edge of the third sub-pole lug is the side away from the fourth sub-pole lug; the fourth pre-welding area is arranged near the bottom edge of the fourth sub-pole lug, and the bottom edge of the fourth sub-pole lug is the side away from the third sub-pole lug.

[0018] In one embodiment, the distance from the center of the first pre-welding area to the bottom edge of the first sub-tab is less than or equal to one-third of the distance from the bottom edge of the first sub-tab to the top edge of the first sub-tab;

[0019] The distance from the center of the second pre-welding area to the bottom edge of the second sub-electrode tab is less than or equal to one-third of the distance from the bottom edge of the second sub-electrode tab to the top edge of the second sub-electrode tab;

[0020] The distance from the center of the third pre-welding area to the bottom edge of the third sub-tab is less than or equal to one-third of the distance from the bottom edge of the third sub-tab to the top edge of the third sub-tab;

[0021] The distance from the center of the fourth pre-welding area to the bottom edge of the fourth sub-tab is less than or equal to one third of the distance from the bottom edge of the fourth sub-tab to the top edge of the fourth sub-tab.

[0022] In one embodiment, the ratio of the length of the positive electrode plate to the length of the first sub-electrode tab is 3.2:1 to 3.4:1, and the ratio of the width of the positive electrode plate to the length of the second sub-electrode tab is 2.0:1 to 2.2:1;

[0023] The ratio of the length of the negative electrode plate to the length of the third sub-electrode tab is 3.3:1 to 3.5:1, and the ratio of the width of the negative electrode plate to the length of the fourth sub-electrode tab is 2.1:1 to 2.3:1.

[0024] In one embodiment, the ratio of the long side to the short side of the first sub-tab is 8.4:1 to 8.8:1, and the ratio of the long side to the short side of the second sub-tab is 1.6:1 to 2.1:1;

[0025] The ratio of the long side to the short side of the third sub-tab is 8.4:1 to 8.8:1, and the ratio of the long side to the short side of the fourth sub-tab is 1.6:1 to 2.1:1.

[0026] In one embodiment, the first pin member includes a first pin segment and a second pin segment; the first end of the first pin segment is connected to the first end of the second pin segment; the second end of the first pin segment is provided with a first connecting portion, and the second end of the second pin segment is provided with a second connecting portion; the first sub-electrode tab is provided with a first bending portion, and the second sub-electrode tab is provided with a second bending portion; the first connecting portion is plugged into the first bending portion, and the second connecting portion is plugged into the second bending portion; the first pin segment and the second pin segment form a first preset angle;

[0027] The second pin component includes a third pin segment and a fourth pin segment; the first end of the third pin segment is connected to the first end of the fourth pin segment; the second end of the third pin segment is provided with a third connecting portion, and the second end of the fourth pin segment is provided with a fourth connecting portion; the third sub-pole ear is provided with a third bending portion, and the fourth sub-pole ear is provided with a fourth bending portion; the third connecting portion is plugged into the third bending portion, and the fourth connecting portion is plugged into the fourth bending portion; the third pin segment and the fourth pin segment form a second preset angle.

[0028] In one embodiment, the first connection portion protrudes from the first lead segment along the width direction of the first lead segment, and the second connection portion protrudes from the second lead segment along the width direction of the second lead segment;

[0029] And / or, the third connection portion protrudes from the third lead segment along the width direction of the third lead segment, and the fourth connection portion protrudes from the fourth lead segment along the width direction of the fourth lead segment.

[0030] In one embodiment, the second end of the second lead segment is provided with at least two second connecting portions, and a first hollow gap is formed between two adjacent second connecting portions;

[0031] And / or, the second end of the fourth pin segment is provided with at least two fourth connecting portions, and a second hollow gap is defined between two adjacent fourth connecting portions.

[0032] In one embodiment, the second end of the first lead segment is provided with at least two first connecting portions, and two adjacent first connecting portions are closed.

[0033] And / or, the second end of the third pin segment is provided with at least two third connecting portions, and two adjacent third connecting portions are closed.

[0034] In one embodiment, the first pin segment and / or the second pin segment is provided with a plurality of first weight-reducing through holes;

[0035] The third pin segment and / or the fourth pin segment is provided with a plurality of second weight-reducing through holes.

[0036] In one embodiment, the negative electrode sheet and the positive electrode sheet are stacked, and the long side of the negative electrode sheet protrudes beyond the long side of the positive electrode sheet, and the protruding distance of the long side is 5 to 6 mm; the short side of the negative electrode sheet protrudes beyond the short side of the positive electrode sheet, and the protruding distance of the short side is 6 to 7 mm.

[0037] In one embodiment, the pole piece connection assembly further includes a first insulating member and a second insulating member; the first insulating member covers the connection between the first pin member and the first pole tab; the second insulating member covers the connection between the second pin member and the second pole tab.

[0038] In one embodiment, a separator is stacked between adjacent positive and negative electrode sheets;

[0039] The long side of the diaphragm protrudes from the long side of the negative electrode sheet, and the protruding distance of the long side is 5 to 6 mm; the short side of the diaphragm protrudes from the short side of the negative electrode sheet, and the protruding distance of the short side is 6 to 7 mm.

[0040] In one embodiment, the ratio of the area of ​​the first insulating member to the area of ​​the first tab is 1.4:1 to 1.6:1;

[0041] The ratio of the area of ​​the second insulating member to the area of ​​the second tab is 1.4:1 to 1.6:1.

[0042] In a second aspect, the present application provides a battery comprising a diaphragm and a pole piece connection assembly according to any one of claims 1 to 8; the diaphragm is stacked between adjacent positive pole pieces and negative pole pieces.

[0043] In one embodiment, the battery further includes a cover plate, the cover plate being provided with a positive electrode post and a negative electrode post;

[0044] The first pin is connected to the positive electrode, and the second pin is connected to the negative electrode.

[0045] One of the above technical solutions has the following advantages and beneficial effects:

[0046] The above-mentioned electrode connection assembly includes an electrode assembly and a pin assembly. The electrode assembly includes at least one positive electrode sheet and at least one negative electrode sheet, and at least two sides of the positive electrode sheet are provided with a first electrode tab, and at least two sides of the negative electrode sheet are provided with a second electrode tab. The pin assembly includes a first pin member and a second pin member, and the first pin member is respectively connected to each first electrode tab of the corresponding positive electrode sheet, and the second pin member is respectively connected to each second electrode tab of the corresponding negative electrode sheet, thereby achieving connection between the positive electrode sheet and the negative electrode sheet. The present application provides a first electrode tab on at least two sides of the positive electrode sheet and connects each first electrode tab with the first pin member, thereby uniformly distributing the current on the positive electrode sheet, and provides a second electrode tab on at least two sides of the negative electrode sheet and connects each second electrode tab with the second pin member, thereby uniformly distributing the current on the negative electrode sheet, thereby reducing the internal resistance of the battery after the electrode connection assembly is assembled into a battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 This is a schematic diagram of the first exploded structure of the electrode connection assembly in an embodiment of the present application;

[0048] Figure 2 Schematic diagram of the assembly structure of the electrode connection assembly in the embodiment of the present application;

[0049] Figure 3 This is a schematic diagram of the partial assembly structure of the pole piece connection assembly from a first perspective in an embodiment of the present application;

[0050] Figure 4 This is a schematic diagram of the partial assembly structure of the pole piece connection assembly from a second perspective in an embodiment of the present application;

[0051] Figure 5 This is a schematic diagram of a second exploded structure of the electrode connection assembly in an embodiment of the present application;

[0052] Figure 6 This is a schematic diagram of the third decomposed structure of the electrode connection assembly in the embodiment of the present application.

[0053] Reference numerals:

[0054] 10. Pole piece assembly; 110. Positive pole piece; 112. First pole piece; 114. First sub-pole piece; 1142. First pre-welding area; 1144. First bend; 1146. Bottom edge of first sub-pole piece; 116. Second sub-pole piece; 1162. Second pre-welding area; 1164. Second bend; 1166. Bottom edge of second sub-pole piece; 120. Negative pole piece; 122. Second pole piece; 124. Third sub-pole piece; 1242. Third pre-welding area; 1244. Third bend; 1246. Bottom edge of third sub-pole piece; 126. Fourth sub-pole piece; 1262. Fourth pre-welding area; 1 264, fourth bending portion; 1266, bottom edge of fourth sub-pole ear; 20, pin assembly; 210, first pin member; 212, first pin segment; 2122, first connecting portion; 214, second pin segment; 2142, second connecting portion; 2144, first hollow gap; 220, second pin member; 222, third pin segment; 2222, third connecting portion; 224, fourth pin segment; 2242, fourth connecting portion; 2244, second hollow gap; 226, first weight-reducing through hole; 228, second weight-reducing through hole; 30, diaphragm; 40, cover plate; 50, positive electrode; 60, negative electrode. DETAILED DESCRIPTION

[0055] In order to enable those skilled in the art to better understand the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of this application.

[0056] It should be noted that the terms "first," "second," and the like in the specification and claims of the present application and the accompanying drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or precedence. It should be understood that the numerals used in this manner are interchangeable where appropriate for the embodiments of the present application described herein. In addition, the terms "including" and "having," as well as any variations thereof, are intended to cover inclusions that are not listed. For example, a process, method, system, product, or apparatus comprising a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or that are inherent to these processes, methods, products, or apparatus.

[0057] In this application, terms such as "upper," "lower," "left," "right," "front," "back," "top," "bottom," "inner," "outer," "center," "vertical," "horizontal," "transverse," and "longitudinal" indicate positions or locations based on the positions or locations shown in the accompanying drawings. These terms are primarily intended to better describe this application and its embodiments and are not intended to limit the devices, elements, or components indicated to having a specific orientation, or to being constructed or operated in a specific orientation.

[0058] Furthermore, some of the above terms may be used to express other meanings besides indicating a position or location. For example, the term "on" may also be used to express a dependency or connection in certain circumstances. Those skilled in the art will understand the specific meanings of these terms in this application based on the specific circumstances.

[0059] Additionally, the term "plurality" shall mean two or more.

[0060] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in this application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0061] In one embodiment, Figure 1 and Figure 6 As shown, a pole piece connection assembly is provided, including a pole piece assembly 10 and a pin assembly 20, the pole piece assembly 10 includes at least one positive pole piece 110 and at least one negative pole piece 120, at least two sides of the positive pole piece 110 are provided with a first pole ear 112, and at least two sides of the negative pole piece 120 are provided with a second pole ear 122; the pin assembly 20 includes a first pin component 210 and a second pin component 220, the first pin component 210 is respectively connected to each first pole ear 112 of the corresponding positive pole piece 110, and the second pin component 220 is respectively connected to each second pole ear 122 of the corresponding negative pole piece 120.

[0062] The electrode assembly 10 may be composed of at least two electrode sheets, each of which may include at least one positive electrode sheet 110 and at least one negative electrode sheet 120. The positive electrode sheet 110 has a sheet-like structure, having a first surface and a second surface opposite to each other. The first and second surfaces of the positive electrode sheet 110 are respectively provided with a lithium iron phosphate active material layer. For example, the lithium iron phosphate active material layer may be provided on the first and second surfaces of the positive electrode sheet 110 by coating. The negative electrode sheet 120 has a sheet-like structure, having a first and second surface opposite to each other. The first and second surfaces of the negative electrode sheet 120 are respectively provided with a graphite active material layer. For example, the graphite active material layer may be provided on the first and second surfaces of the negative electrode sheet 120 by coating.

[0063] The positive electrode sheet 110 may be square in shape. For example, the positive electrode sheet 110 may have four sides. A first electrode tab 112 may be provided on at least two sides of the positive electrode sheet 110, and the first electrode tab 112 and the positive electrode sheet 110 may be integrally formed. The positive electrode sheet 110 may include a first side, a second side, a third side, and a fourth side. For example, the first electrode tab 112 may be provided on the first side of the positive electrode sheet 110, and the first electrode tab 112 may be provided on the second side of the positive electrode sheet 110. In another example, the first electrode tab 112 may be provided on the second side of the positive electrode sheet 110, and the first electrode tab 112 may be provided on the third side of the positive electrode sheet 110. The negative electrode sheet 120 can be square in shape. For example, the negative electrode sheet 120 has four sides. A second electrode tab 122 can be provided on at least two sides of the negative electrode sheet 120. The second electrode tab 122 and the negative electrode sheet 120 are integrally formed. The negative electrode sheet 120 includes a first side, a second side, a third side, and a fourth side. For example, the second electrode tab 122 can be provided on the first side of the negative electrode sheet 120 and the second electrode tab 122 can be provided on the second side of the negative electrode sheet 120. In another example, the second electrode tab 122 can be provided on the second side of the negative electrode sheet 120 and the second electrode tab 122 can be provided on the third side of the negative electrode sheet 120.

[0064] The first pin member 210 is a flexible connector with conductive properties, and the second pin member 220 is a flexible connector with conductive properties. The first pin member 210 can be bent and used to connect to each first electrode tab 112 on the positive electrode sheet 110; the second pin member 220 can be bent and used to connect to each second electrode tab 122 on the negative electrode sheet 120. For example, each first electrode tab 112 can be ultrasonically welded to the first pin member 210 to achieve an electrical connection between the first electrode tab 112 and the first pin member 210; each second electrode tab 122 can be ultrasonically welded to the second pin member 220 to achieve an electrical connection between the second electrode tab 122 and the second pin member 220.

[0065] Exemplarily, the electrode connection assembly is applied to a battery, which includes a cover plate 40, on which a positive electrode post 50 and a negative electrode post 60 are provided. The first pin member 210 can be set on the cover plate 40 by laser welding to achieve electrical connection between the first pin member 210 and the positive electrode post 50; the second pin member 220 can be set on the cover plate 40 by laser welding to achieve electrical connection between the second pin member 220 and the negative electrode post 60, thereby evenly distributing the current inside the battery and reducing the internal resistance of the battery.

[0066] In the above embodiment, the electrode assembly 10 includes at least one positive electrode sheet 110 and at least one negative electrode sheet 120, at least two sides of the positive electrode sheet 110 are provided with a first electrode ear 112, and at least two sides of the negative electrode sheet 120 are provided with a second electrode ear 122; the pin assembly 20 includes a first pin component 210 and a second pin component 220, the first pin component 210 is respectively connected to each first electrode ear 112 of the corresponding positive electrode sheet 110, and the second pin component 220 is respectively connected to each second electrode ear 122 of the corresponding negative electrode sheet 120, thereby realizing the connection between the positive electrode sheet 110 and the negative electrode sheet 120. The present application provides a first electrode tab 112 on at least two sides of the positive electrode sheet 110, and connects each first electrode tab 112 through a first pin member 210, thereby evenly distributing the current on the positive electrode sheet 110; provides a second electrode tab 122 on at least two sides of the negative electrode sheet 120, and connects each second electrode tab 122 through a second pin member 220, thereby evenly distributing the current on the negative electrode sheet 120, thereby reducing the internal resistance of the battery after the battery is assembled by the electrode connection assembly.

[0067] In one embodiment, Figure 2 、 Figure 3 and Figure 4 As shown, the positive electrode sheet 110 has an adjacent first side and a second side, and the first electrode tab 112 includes a first sub-pole tab 114 and a second sub-pole tab 116; the first side of the positive electrode sheet 110 is provided with a first sub-pole tab 114, and the second side of the positive electrode sheet 110 is provided with a second sub-pole tab 116, and the first pin component 210 connects the first sub-pole tab 114 and the second sub-pole tab 116; the negative electrode sheet 120 has an adjacent first side and a second side, and the second electrode tab 122 includes a third sub-pole tab 124 and a fourth sub-pole tab 126; the first side of the negative electrode sheet 120 is provided with a third sub-pole tab 124, and the second side of the negative electrode sheet 120 is provided with a fourth sub-pole tab 126, and the second pin component 220 connects the third sub-pole tab 124 and the fourth sub-pole tab 126.

[0068] Among them, the first side of the positive electrode sheet 110 can be the left side, the second side of the positive electrode sheet 110 can be the top side, the second side of the positive electrode sheet 110 is adjacent to the battery cover 40, the first sub-pole ear 114 can be set on the first side of the positive electrode sheet 110 by an integrated molding method, and the second sub-pole ear 116 can be set on the second side of the positive electrode sheet 110 by an integrated molding method.

[0069] For example, the first sub-tab 114 can be bent to form a first accommodating cavity, the first end of the first pin member 210 can be inserted into the first accommodating cavity of the first sub-tab 114, and the first end of the first pin member 210 can be fixed to the first sub-tab 114 by ultrasonic welding, thereby improving the connection reliability between the first pin member 210 and the first sub-tab 114. Similarly, the second sub-tab 116 can be bent to form a second accommodating cavity, the second end of the first pin member 210 can be inserted into the second accommodating cavity of the second sub-tab 116, and the second end of the first pin member 210 can be fixed to the second sub-tab 116 by ultrasonic welding, thereby improving the connection reliability between the first pin member 210 and the second sub-tab 116, thereby achieving uniform current distribution on the positive electrode sheet 110.

[0070] The third sub-tab 124 can be bent to form a third accommodating cavity, and the first end of the second pin member 220 can be inserted into the third accommodating cavity of the third sub-tab 124. The first end of the second pin member 220 can be fixed to the third sub-tab 124 by ultrasonic welding, thereby improving the connection reliability between the second pin member 220 and the third sub-tab 124. Similarly, the fourth sub-tab 126 can be bent to form a fourth accommodating cavity, and the second end of the second pin member 220 can be inserted into the fourth accommodating cavity of the fourth sub-tab 126. The second end of the second pin member 220 can be fixed to the fourth sub-tab 126 by ultrasonic welding, thereby improving the connection reliability between the second pin member 220 and the fourth sub-tab 126, thereby achieving uniform current distribution on the negative electrode sheet 120 and reducing the internal resistance of the battery after the electrode sheet connection assembly is assembled into a battery.

[0071] In one embodiment, Figure 5 and Figure 6 As shown, the first sub-pole tab 114 is provided with a first pre-welding area 1142, the second sub-pole tab 116 is provided with a second pre-welding area 1162, the third sub-pole tab 124 is provided with a third pre-welding area 1242, and the fourth sub-pole tab 126 is provided with a fourth pre-welding area 1262; the first end of the first pin component 210 is provided in the first pre-welding area 1142, and the second end of the first pin component 210 is provided in the second pre-welding area 1162; the first end of the second pin component 220 is provided in the third pre-welding area 1242, and the second end of the second pin component 220 is provided in the fourth pre-welding area 1262.

[0072] Exemplarily, a separator 30 is disposed between the positive electrode sheet 110 and the negative electrode sheet 120. The positive electrode sheet 110, the separator 30, and the negative electrode sheet 120 are stacked one on another to form a core package having a cluster of four tabs. Solder is applied to the first pre-welding region 1142 of the first sub-tab 114, the second pre-welding region 1162 of the second sub-tab 116, the third pre-welding region 1242 of the third sub-tab 124, and the fourth pre-welding region 1262 of the fourth sub-tab 126, respectively, to pre-weld the first sub-tab 114, the second sub-tab 116, the third sub-tab 124, and the fourth sub-tab 126. By arranging the first pin member 210 and the second pin member 220 on the cover plate 40 by laser welding, the first end of the first pin member 210 can be welded to the first pre-welding area 1142 of the first sub-pole tab 114 by ultrasonic welding, and the first end of the second pin member 220 can be welded to the third pre-welding area 1242 of the third sub-pole tab 124 by ultrasonic welding; after the core is wrapped with the core, the second end of the first pin member 210 can be welded to the second pre-welding area 1162 of the second sub-pole tab 116 by ultrasonic welding, and the second end of the second pin member 220 can be welded to the fourth pre-welding area 1262 of the fourth sub-pole tab 126 by ultrasonic welding, thereby realizing electrical connection of the positive and negative electrode sheets, simplifying the assembly method of large-size stacked batteries, ensuring that the internal current of the battery is evenly distributed in the longitudinal and transverse directions, and reducing the internal resistance of the battery.

[0073] In one embodiment, Figure 5 and Figure 6 As shown, the first pre-welding area 1142 is arranged near the bottom edge 1146 of the first sub-pole lug, and the bottom edge 1146 of the first sub-pole lug is the side away from the second sub-pole lug 116; the second pre-welding area 1162 is arranged near the bottom edge 1166 of the second sub-pole lug, and the bottom edge 1166 of the second sub-pole lug is the side away from the first sub-pole lug 114; the third pre-welding area 1242 is arranged near the bottom edge 1246 of the third sub-pole lug, and the bottom edge 1246 of the third sub-pole lug is the side away from the fourth sub-pole lug 126; the fourth pre-welding area 1262 is arranged near the bottom edge 1266 of the fourth sub-pole lug, and the bottom edge 1266 of the fourth sub-pole lug is the side away from the third sub-pole lug 124.

[0074] Illustratively, the distance from the center of the first pre-weld area 1142 to the bottom edge 1146 of the first sub-pole lug is less than or equal to one-third of the distance from the bottom edge 1146 of the first sub-pole lug to the top edge of the first sub-pole lug 114; the distance from the center of the second pre-weld area 1162 to the bottom edge 1166 of the second sub-pole lug is less than or equal to one-third of the distance from the bottom edge 1166 of the second sub-pole lug to the top edge of the second sub-pole lug 116; the distance from the center of the third pre-weld area 1242 to the bottom edge 1246 of the third sub-pole lug is less than or equal to one-third of the distance from the bottom edge 1246 of the third sub-pole lug to the top edge of the third sub-pole lug 124; the distance from the center of the fourth pre-weld area 1262 to the bottom edge 1266 of the fourth sub-pole lug is less than or equal to one-third of the distance from the bottom edge 1266 of the fourth sub-pole lug to the top edge of the fourth sub-pole lug 126.

[0075] The first sub-tab 114 has opposing bottom and top edges, and the first pre-welding region 1142 is disposed adjacent to the bottom edge 1146 of the first sub-tab. Exemplarily, the distance from the center of the first pre-welding region 1142 to the bottom edge 1146 of the first sub-tab may be one-third of the distance from the bottom edge 1146 to the top edge of the first sub-tab, so that the first end of the first pin 210 is electrically connected to the first pre-welding region 1142 of the first sub-tab 114. It should be noted that the bottom edge 1146 of the first sub-tab refers to the side adjacent to the bottom of the battery, and the top edge of the first sub-tab refers to the side adjacent to the top of the battery, that is, the bottom edge 1146 of the first sub-tab refers to the side away from the second sub-tab 116. Similarly, the second sub-tab 116 has opposing bottom and top edges, and the second pre-weld region 1162 is disposed adjacent to the bottom edge 1166 of the second sub-tab. Exemplarily, the distance from the center of the second pre-weld region 1162 to the bottom edge 1166 of the second sub-tab may be one-third of the distance from the bottom edge 1166 to the top edge of the second sub-tab, such that the second end of the first lead 210 is electrically connected to the second pre-weld region 1162 of the second sub-tab 116. It should be noted that the second sub-tab 116 is located on the top surface of the battery. Therefore, the bottom edge 1166 of the second sub-tab refers to the side adjacent to the middle of the battery top surface, and the top edge of the second sub-tab refers to the side adjacent to the side end of the battery top surface. That is, the bottom edge 1166 of the second sub-tab refers to the side away from the first sub-tab 114. The third sub-tab 124 has opposing bottom and top edges, and the third pre-welding region 1242 is disposed adjacent to the bottom edge 1246 of the third sub-tab. Exemplarily, the distance from the center of the third pre-welding region 1242 to the bottom edge 1246 of the third sub-tab may be one-third of the distance from the bottom edge 1246 to the top edge of the third sub-tab, so that the first end of the second lead 220 is electrically connected to the third pre-welding region 1242 of the third sub-tab 124. It should be noted that the bottom edge 1246 of the third sub-tab refers to the side adjacent to the bottom of the battery, and the top edge of the third sub-tab refers to the side adjacent to the top of the battery, i.e., the bottom edge 1246 of the third sub-tab refers to the side away from the fourth sub-tab 126. The fourth sub-tab 126 has opposing bottom and top edges, and a fourth pre-welding region 1262 is disposed adjacent to the bottom edge 1266 of the fourth sub-tab. Exemplarily, the distance from the center of the fourth pre-welding region 1262 to the bottom edge 1266 of the fourth sub-tab may be one-third of the distance from the bottom edge 1266 to the top edge of the fourth sub-tab, such that the second end of the second lead 220 is electrically connected to the fourth pre-welding region 1262 of the fourth sub-tab 126. It should be noted that the fourth sub-tab 126 is located on the top surface of the battery. Therefore, the bottom edge 1266 of the fourth sub-tab refers to the side adjacent to the middle of the battery top surface, and the top edge of the fourth sub-tab refers to the side adjacent to the side end of the battery top surface. That is, the bottom edge 1266 of the fourth sub-tab refers to the side away from the third sub-tab 124.

[0076] In one embodiment, Figures 2 to 6 As shown, the first pin member 210 includes a first pin segment 212 and a second pin segment 214; the first end of the first pin segment 212 is connected to the first end of the second pin segment 214; the second end of the first pin segment 212 is provided with a first connecting portion 2122, and the second end of the second pin segment 214 is provided with a second connecting portion 2142; the first sub-pole ear 114 is provided with a first bending portion 1144, and the second sub-pole ear 116 is provided with a second bending portion 1164; the first connecting portion 2122 is plugged into the first bending portion 1144, and the second connecting portion 2142 is plugged into the second bending portion 1164; the first pin segment 212 and the second pin segment 214 are in a first preset clamping position. Angle; the second pin component 220 includes a third pin segment 222 and a fourth pin segment 224; the first end of the third pin segment 222 is connected to the first end of the fourth pin segment 224; the second end of the third pin segment 222 is provided with a third connecting portion 2222, and the second end of the fourth pin segment 224 is provided with a fourth connecting portion 2242; the third sub-pole ear 124 is provided with a third bending portion 1244, and the fourth sub-pole ear 126 is provided with a fourth bending portion 1264; the third connecting portion 2222 is plugged into the third bending portion 1244, and the fourth connecting portion 2242 is plugged into the fourth bending portion 1264; the third pin segment 222 and the fourth pin segment 224 form a second preset angle.

[0077] The first lead segment 212 and the second lead segment 214 can be formed by bending, and the first predetermined angle between the first lead segment 212 and the second lead segment 214 can be 90 degrees. The third lead segment 222 and the fourth lead segment 224 can be formed by bending, and the first predetermined angle between the third lead segment 222 and the fourth lead segment 224 can be 90 degrees.

[0078] The first connecting portion 2122 is used to plug into the first bent portion 1144 to positionally secure the first lead segment 212, thereby facilitating the welding of the first lead segment 212 to the first sub-tab. Similarly, the second connecting portion 2142 is used to plug into the second bent portion 1164 to positionally secure the second lead segment 214, thereby facilitating the welding of the second lead segment 214 to the second sub-tab. The third connecting portion 2222 is used to plug into the third bent portion 1244 to positionally secure the third lead segment 222, thereby facilitating the welding of the third lead segment 222 to the third sub-tab. The fourth connecting portion 2242 is used to plug into the fourth bent portion 1264 to positionally secure the fourth lead segment 224, thereby facilitating the welding of the fourth lead segment 224 to the fourth sub-tab.

[0079] For example, the first sub-tab 114 can be bent to form a first bent portion 1144, which has a first accommodating cavity. The first connecting portion 2122 of the first pin member 210 can be inserted into the first accommodating cavity of the first sub-tab 114, and the first connecting portion 2122 of the first pin member can be fixed to the first sub-tab 114 by ultrasonic welding, thereby improving the connection reliability between the first pin member 210 and the first sub-tab 114. Similarly, the second sub-tab 116 can be bent to form a second bent portion 1164, which has a second accommodating cavity. The second connecting portion 2142 of the first pin member 210 can be inserted into the second accommodating cavity of the second sub-tab 116, and the second connecting portion 2142 of the first pin member 210 can be fixed to the second sub-tab 116 by ultrasonic welding, thereby improving the connection reliability between the first pin member 210 and the second sub-tab 116, thereby achieving uniform current distribution on the positive electrode sheet 110.

[0080] For another example, the third sub-pole ear 124 can be bent into a third bending portion 1244, and the third bending portion 1244 has a third accommodating cavity. The third connecting portion 2222 of the second pin component 220 can be inserted into the third accommodating cavity of the third sub-pole ear 124, and the third connecting portion 2222 of the second pin component 220 can be fixed to the third sub-pole ear 124 by ultrasonic welding, thereby improving the connection reliability between the second pin component 220 and the third sub-pole ear 124. Similarly, the fourth sub-pole ear 126 can be bent to form a fourth connecting portion 2242, and the fourth connecting portion 2242 has a fourth accommodating cavity. The fourth connecting portion 2242 of the second pin component 220 can be inserted into the fourth accommodating cavity of the fourth sub-pole ear 126, and the fourth connecting portion 2242 of the second pin component 220 is fixed to the fourth sub-pole ear 126 by ultrasonic welding, thereby improving the connection reliability between the second pin component 220 and the fourth sub-pole ear 126, thereby achieving uniform distribution of current on the negative electrode plate 120, and reducing the internal resistance of the battery after the plate connection component is assembled into a battery.

[0081] In one embodiment, Figure 5 As shown, the first connection portion 2122 protrudes from the first pin segment 212 along the width direction of the first pin segment 212, and the second connection portion 2142 protrudes from the second pin segment 214 along the width direction of the second pin segment 214; and / or, the third connection portion 2222 protrudes from the third pin segment 222 along the width direction of the third pin segment 222, and the fourth connection portion 2242 protrudes from the fourth pin segment 224 along the width direction of the fourth pin segment 224.

[0082] The direction from the first end to the second end of the first lead segment 212 is the length direction of the first lead segment 212, and the width direction of the first lead segment 212 is perpendicular to the length direction of the first lead segment 212. Similarly, the direction from the first end to the second end of the second lead segment 214 is the length direction of the second lead segment 214, and the width direction of the second lead segment 214 is perpendicular to the length direction of the second lead segment 214. The direction from the first end to the second end of the third lead segment 222 is the length direction of the third lead segment 222, and the width direction of the third lead segment 222 is perpendicular to the length direction of the third lead segment 222. The direction from the first end to the second end of the fourth lead segment 224 is the length direction of the fourth lead segment 224, and the width direction of the fourth lead segment 224 is perpendicular to the length direction of the fourth lead segment 224.

[0083] By making the first connection portion 2122 protrude from the first lead segment 212, the contact area between the first connection portion 2122 and the first bend portion is increased, thereby enhancing the connection security between the first connection portion 2122 and the first bend portion. Similarly, by making the second connection portion 2142 protrude from the second lead segment 214, the contact area between the second connection portion 2142 and the second bend portion is increased, thereby enhancing the connection security between the second connection portion 2142 and the second bend portion. By making the third connection portion 2222 protrude from the third lead segment 222, the contact area between the third connection portion 2222 and the third bend portion is increased, thereby enhancing the connection security between the third connection portion 2222 and the third bend portion. By making the fourth connection portion 2242 protrude from the fourth lead segment 224, the contact area between the fourth connection portion 2242 and the fourth bend portion is increased, thereby enhancing the connection security between the fourth connection portion 2242 and the fourth bend portion.

[0084] In one embodiment, Figure 6 As shown, the second end of the second pin segment 214 is provided with at least two second connection parts 2142, and a first hollow gap 2144 is provided between the two adjacent second connection parts 2142; and / or, the second end of the fourth pin segment 224 is provided with at least two fourth connection parts 2242, and a second hollow gap 2244 is provided between the two adjacent fourth connection parts 2242.

[0085] The first hollow notch 2144 and the second hollow notch 2244 can be rectangular or arc-shaped. Providing the first hollow notch 2144 between two adjacent second connecting portions 2142 can reduce the weight of the first pin member 210, thereby reducing the overall weight of the battery. Similarly, providing the second hollow notch 2244 between two adjacent fourth connecting portions 2242 can reduce the weight of the second pin member 220, thereby reducing the overall weight of the battery.

[0086] In one embodiment, Figure 6 As shown, the second end of the first pin segment 212 is provided with at least two first connection parts 2122, and the two adjacent first connection parts 2122 are closed; and / or, the second end of the third pin segment 222 is provided with at least two third connection parts 2222, and the two adjacent third connection parts 2222 are closed.

[0087] By enclosing the first connecting portions 2122 between two adjacent first connecting portions, each first connecting portion 2122 forms a flat plate structure. This prevents the first bending portion from being inserted into the first bending portion and causing a battery short circuit. By enclosing the third connecting portions 2222 between two adjacent third connecting portions 2222, each third connecting portion 2222 forms a flat plate structure. This prevents the third bending portion from being inserted into the third bending portion and causing a battery short circuit.

[0088] In one embodiment, Figure 6 As shown, the first pin segment 212 and / or the second pin segment 214 are provided with a plurality of first weight-reducing through holes 226 ; the third pin segment 222 and / or the fourth pin segment 224 are provided with a plurality of second weight-reducing through holes 228 .

[0089] The first weight-reducing through hole 226 and the second weight-reducing through hole 228 may be circular holes. Providing the first weight-reducing through hole 226 in the first lead segment 212 and / or the second lead segment 214 can reduce the weight of the first lead assembly 210, further reducing the overall weight of the battery. Providing the second weight-reducing through hole 228 in the third lead segment 222 and / or the fourth lead segment 224 can reduce the weight of the second lead assembly 220, further reducing the overall weight of the battery.

[0090] In one embodiment, a first final welding area is provided in the first pre-welding area 1142, a second final welding area is provided in the second pre-welding area 1162, a third final welding area is provided in the third pre-welding area 1242, and a fourth final welding area is provided in the fourth pre-welding area 1262; the first end of the first pin component 210 is connected to the first final welding area, and the second end of the first pin component 210 is connected to the second final welding area; the first end of the second pin component 220 is connected to the third final welding area, and the second end of the second pin component 220 is connected to the fourth final welding area; the area of ​​the first pre-welding area 1142 is larger than the area of ​​the first final welding area, the area of ​​the second pre-welding area 1162 is larger than the area of ​​the second final welding area, the area of ​​the third pre-welding area 1242 is larger than the area of ​​the third final welding area, and the area of ​​the fourth pre-welding area 1262 is larger than the area of ​​the fourth final welding area.

[0091] Among them, the first final welding area refers to the area where the first end of the first pin component 210 is actually welded, the second final welding area refers to the area where the second end of the first pin component 210 is actually welded, the third final welding area refers to the area where the first end of the second pin component 220 is actually welded, and the fourth final welding area refers to the area where the second end of the second pin component 220 is actually welded.

[0092] In one embodiment, the area ratio of the first pre-weld region 1142 to the area ratio of the first final weld region is 1.8:1 to 2.2:1, the area ratio of the second pre-weld region 1162 to the area ratio of the second final weld region is 1.8:1 to 2.2:1, the area ratio of the third pre-weld region 1242 to the area ratio of the third final weld region is 1.8:1 to 2.2:1, and the area ratio of the fourth pre-weld region 1262 to the area ratio of the fourth final weld region is 1.8:1 to 2.2:1.

[0093] For example, the ratio of the area of ​​the first pre-welding region 1142 to the area of ​​the first final welding region can be 2:1, the ratio of the area of ​​the second pre-welding region 1162 to the area of ​​the second final welding region can be 2:1, the ratio of the area of ​​the third pre-welding region 1242 to the area of ​​the third final welding region can be 2:1, and the ratio of the area of ​​the fourth pre-welding region 1262 to the area of ​​the fourth final welding region can be 2:1.

[0094] By making the area of ​​the pre-welding area larger than the area of ​​the final welding area, it is convenient to weld the first pin 210 between the first sub-pole tab 114 and the second sub-pole tab 116, and to weld the second pin 220 between the third sub-pole tab 124 and the fourth sub-pole tab 126, thereby improving the assembly convenience of the pole piece.

[0095] In one embodiment, the ratio of the length of the positive electrode tab 110 to the length of the first sub-tab 114 is 3.2:1 to 3.4:1, and the ratio of the width of the positive electrode tab 110 to the length of the second sub-tab 116 is 2.0:1 to 2.2:1. Preferably, the ratio of the length of the positive electrode tab 110 to the length of the first sub-tab 114 is 3.4:1, and the ratio of the width of the positive electrode tab 110 to the length of the second sub-tab 116 is 2.06:1. The ratio of the length of the negative electrode tab 120 to the length of the third sub-tab 124 is 3.3:1 to 3.5:1, and the ratio of the width of the negative electrode tab 120 to the length of the fourth sub-tab 126 is 2.1:1 to 2.3:1. Preferably, the ratio of the length of the negative electrode tab 120 to the length of the third sub-tab 124 is 3.45:1, and the ratio of the width of the negative electrode tab 120 to the length of the fourth sub-tab 126 is 2.13:1.

[0096] The positive electrode sheet 110 may be rectangular in shape, for example, with an aspect ratio of 1.8:1 to 2.1:1; preferably, the aspect ratio of the positive electrode sheet 110 is 2:1. A first sub-electrode tab 114 may be disposed on a short side of the positive electrode sheet 110, with the length of the first sub-electrode tab 114 being shorter than the length of the positive electrode sheet 110 and shorter than the width of the positive electrode sheet 110. A second sub-electrode tab 116 may be disposed on a long side of the positive electrode sheet 110, with the length of the second sub-electrode tab 116 being shorter than the width of the positive electrode sheet 110. The negative electrode sheet 120 may be rectangular in shape, for example, with an aspect ratio of 1.8:1 to 2.1:1; preferably, the aspect ratio of the negative electrode sheet 120 is 2:1. The third sub-pole tab 124 can be set on the short side of the negative electrode sheet 120, and the length of the third sub-pole tab 124 is less than the length of the negative electrode sheet 120, and the length of the third sub-pole tab 124 is less than the width of the negative electrode sheet 120; the fourth sub-pole tab 126 can be set on the long side of the negative electrode sheet 120, and the length of the fourth sub-pole tab 126 is less than the width of the negative electrode sheet 120.

[0097] By setting the size ratio of the positive electrode sheet 110, the first sub-pole tab 114 and the second sub-pole tab 116, it is ensured that the current of the positive electrode sheet 110 can be evenly distributed in the longitudinal and transverse directions, thereby improving the current uniformity of the positive electrode sheet 110; by setting the size ratio of the negative electrode sheet 120, the third sub-pole tab 124 and the fourth sub-pole tab 126, it is ensured that the current of the negative electrode sheet 120 can be evenly distributed in the longitudinal and transverse directions, thereby improving the current uniformity of the negative electrode sheet 120, thereby reducing the internal resistance of the battery.

[0098] In one embodiment, the ratio of the long side to the short side of the first sub-tab 114 is 8.4:1 to 8.8:1, and the ratio of the long side to the short side of the second sub-tab 116 is 1.6:1 to 2.1:1. Preferably, the ratio of the long side to the short side of the first sub-tab 114 is 8.6:1, and the ratio of the long side to the short side of the second sub-tab 116 is 1.9:1. The ratio of the long side to the short side of the third sub-tab 124 is 8.4:1 to 8.8:1, and the ratio of the long side to the short side of the fourth sub-tab 126 is 1.6:1 to 2.1:1. Preferably, the ratio of the long side to the short side of the third sub-tab 124 is 8.6:1, and the ratio of the long side to the short side of the fourth sub-tab 126 is 1.9:1.

[0099] Among them, the long side distance of the first sub-pole ear 114 refers to the long side distance of the first side of the positive electrode sheet 110 where the first sub-pole ear 114 is located, and the short side distance of the first sub-pole ear 114 refers to the short side distance of the first side of the positive electrode sheet 110 where the first sub-pole ear 114 is located; the long side distance of the second sub-pole ear 116 refers to the long side distance of the second side of the positive electrode sheet 110 where the second sub-pole ear 116 is located, and the short side distance of the second sub-pole ear 116 refers to the short side distance of the second side of the positive electrode sheet 110 where the second sub-pole ear 116 is located. Distance; the long side distance of the third sub-pole tab 124 refers to the long side distance of the first side of the negative electrode sheet 120 where the third sub-pole tab 124 is located, and the short side distance of the third sub-pole tab 124 refers to the short side distance of the first side of the negative electrode sheet 120 where the third sub-pole tab 124 is located; the long side distance of the fourth sub-pole tab 126 refers to the long side distance of the second side of the negative electrode sheet 120 where the fourth sub-pole tab 126 is located, and the short side distance of the fourth sub-pole tab 126 refers to the short side distance of the second side of the negative electrode sheet 120 where the fourth sub-pole tab 126 is located.

[0100] By setting the long side distance and the short side distance of the tabs (the first sub-tab 114, the second sub-tab 116, the third sub-tab 124 and the fourth sub-tab 126), the setting position of the tabs on the side of the corresponding pole piece can be determined, so that the first pin member 210 connects the first sub-tab 114 and the second sub-tab 116, and the second pin member 220 connects the third sub-tab 124 and the fourth sub-tab 126, thereby improving the convenience of pole piece connection and ensuring that the pole piece current can be evenly distributed in the longitudinal and transverse directions, thereby improving the current uniformity of the battery.

[0101] In one embodiment, Figure 1 As shown, the negative electrode sheet 120 and the positive electrode sheet 110 are stacked, and the long side of the negative electrode sheet 120 protrudes from the long side of the positive electrode sheet 110, and the protruding distance of the long side is 5 to 6 mm; the short side of the negative electrode sheet 120 protrudes from the short side of the positive electrode sheet 110, and the protruding distance of the short side is 6 to 7 mm.

[0102] Among them, the area of ​​the negative electrode sheet 120 is larger than the area of ​​the positive electrode sheet 110, the negative electrode sheet 120 and the positive electrode sheet 110 are stacked, and a separator 30 is stacked between the negative electrode sheet 120 and the positive electrode sheet 110. The long side of the negative electrode sheet 120 protrudes from the long side of the positive electrode sheet 110, and the short side of the negative electrode sheet 120 protrudes from the short side of the positive electrode sheet 110, so that the negative electrode tab can completely cover the positive electrode sheet 110, thereby improving the performance of the battery.

[0103] In one embodiment, a diaphragm 30 is stacked between adjacent positive electrode sheets 110 and negative electrode sheets 120; the long side of the diaphragm 30 protrudes beyond the long side of the negative electrode sheet 120, and the protruding distance of the long side is 5 to 6 mm; the short side of the diaphragm 30 protrudes beyond the short side of the negative electrode sheet 120, and the protruding distance of the short side is 6 to 7 mm.

[0104] For example, the total protrusion distance between the diaphragm 30 and the negative electrode sheet 120 in the length direction is 5 to 6 mm, and the total protrusion distance between the diaphragm 30 and the negative electrode sheet 120 in the width direction is 6 to 7 mm. A core package can be formed by stacking multiple groups of diaphragms 30, negative electrode sheets 120, diaphragms 30 and positive electrode sheets 110, thereby forming a core package with four tab areas. The four tab clusters are pre-welded in sequence using ultrasonic welding, and the excess tabs are trimmed and shaped. Further, by welding the first pin 210 between the first sub-tab 114 and the second sub-tab 116, and welding the second pin 220 between the third sub-tab 124 and the fourth sub-tab 126, the current on the positive electrode sheet 110 and the negative electrode sheet 120 is evenly distributed, thereby reducing the internal resistance of the battery after the battery is assembled by the tab connection assembly.

[0105] In one embodiment, the pole piece connection assembly further includes a first insulating member and a second insulating member; the first insulating member covers the connection between the first pin member 210 and the first pole tab 112 ; the second insulating member covers the connection between the second pin member 220 and the second pole tab 122 .

[0106] The ratio of the area of ​​the first insulating member to the area of ​​the first tab 112 is 1.4:1 to 1.6:1; the ratio of the area of ​​the second insulating member to the area of ​​the second tab 122 is 1.4:1 to 1.6:1.

[0107] The first insulating member and the second insulating member may be in the form of thin sheets. The first insulating member and the second insulating member may be insulating glue. The area of ​​the first insulating member is larger than the area of ​​the first tab 112. For example, the area ratio of the first insulating member to the first tab 112 is 1.4:1 to 1.6:1. Preferably, the area ratio of the first insulating member to the first tab 112 is 1.5:1. The area of ​​the second insulating member is larger than the area of ​​the second tab 122. For example, the area ratio of the second insulating member to the second tab 122 is 1.4:1 to 1.6:1. Preferably, the area ratio of the second insulating member to the second tab 122 is 1.5:1.

[0108] Exemplarily, the first sub-pole ear 114 and the third sub-pole ear 124 are first welded to the first end of the first pin member 210 and the first end of the second pin member 220, respectively, and then the first insulating member is bonded to the corresponding connection; the second sub-pole ear 116 and the fourth sub-pole ear 126 are respectively welded to the second end of the first pin member 210 and the second end of the second pin member 220, and the second insulating member is bonded to the corresponding connection, thereby realizing insulation after the pole piece connection is set, thereby improving the reliability of the pole piece after assembly.

[0109] In one embodiment, a battery is further provided, comprising a separator 30 and a pole piece connection assembly as described above; the separator 30 is stacked between adjacent positive pole pieces 110 and negative pole pieces 120 .

[0110] For the detailed description of the diaphragm 30 and the electrode connection assembly, reference may be made to the detailed description of the diaphragm 30 and the electrode connection assembly in the above embodiment, which will not be repeated here.

[0111] The electrode assembly 10 includes at least one positive electrode sheet 110 and at least one negative electrode sheet 120, and a separator 30 is arranged between the positive electrode sheet 110 and the negative electrode sheet 120. For example, the negative electrode sheet 120 is stacked on the first separator 30, the second separator 30 is stacked on the negative electrode sheet 120, and the positive electrode sheet 110 is stacked on the second separator 30. A first electrode tab 112 is provided on at least two sides of the positive electrode sheet 110, and a second electrode tab 122 is provided on at least two sides of the negative electrode sheet 120; the pin assembly 20 includes a first pin component 210 and a second pin component 220, and the first pin component 210 is respectively connected to each first electrode tab 112 of the corresponding positive electrode sheet 110, and the second pin component 220 is respectively connected to each second electrode tab 122 of the corresponding negative electrode sheet 120, so as to realize the connection between the positive electrode sheet 110 and the negative electrode sheet 120.

[0112] In the above-mentioned embodiment, by respectively providing a first pole lug 112 on at least two sides of the positive pole piece 110, and respectively connecting each first pole lug 112 through a first pin member 210, the current on the positive pole piece 110 is evenly distributed, and by respectively providing a second pole lug 122 on at least two sides of the negative pole piece 120, and respectively connecting each second pole lug 122 through a second pin member 220, the current on the negative pole piece 120 is evenly distributed, thereby improving the uniformity of the current distribution inside the battery and reducing the internal resistance of the battery.

[0113] In one embodiment, the battery further includes a cover plate 40 , on which a positive electrode post 50 and a negative electrode post 60 are provided; the first pin 210 is connected to the positive electrode post 50 , and the second pin 220 is connected to the negative electrode post 60 .

[0114] Among them, the cover plate 40 has a first surface and a second surface relative to each other, and the first surface of the cover plate 40 is provided with a positive electrode column 50 and a negative electrode column 60. The first pin component 210 can be welded to the second surface of the cover plate 40 by laser welding, and the second pin component 220 can be welded to the second surface of the cover plate 40 by laser welding. The first pin component 210 is electrically connected to the positive electrode column 50, and the second pin component 220 is electrically connected to the negative electrode column 60. The first pin component 210 is connected to each first pole ear 112 of the positive electrode sheet 110, and the second pin component 220 is connected to each second pole ear 122 of the negative electrode sheet 120, thereby realizing the electrical connection of the positive and negative electrode sheets, simplifying the assembly method of large-size stacked batteries, ensuring that the internal current of the battery is evenly distributed in the longitudinal and transverse directions, and reducing the internal resistance of the battery.

[0115] It should be noted that the battery may further include components such as a housing, and a specific battery may include more components than those described in the above embodiments, or combine certain components, or have a different arrangement of components.

[0116] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0117] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the utility model patent. It should be noted that a person skilled in the art could make various modifications and improvements without departing from the spirit of the present application, all of which fall within the scope of protection of the present application. Therefore, the scope of protection of the present patent application shall be determined by the appended claims.

Claims

1. A pole piece connection assembly, characterized in that: include: A pole piece assembly, the pole piece assembly comprising at least one positive pole piece and at least one negative pole piece, at least two sides of the positive pole piece are provided with a first pole tab, and at least two sides of the negative pole piece are provided with a second pole tab; The pin assembly includes a first pin member and a second pin member, wherein the first pin member is respectively connected to each of the first tabs of the corresponding positive electrode sheet, and the second pin member is respectively connected to each of the second tabs of the corresponding negative electrode sheet.

2. The pole piece connection assembly according to claim 1, characterized in that: The positive electrode plate has a first side and a second side adjacent to each other, and the first electrode tab includes a first sub-electrode tab and a second sub-electrode tab; the first sub-electrode tab is provided on the first side of the positive electrode plate, and the second sub-electrode tab is provided on the second side of the positive electrode plate, and the first pin connects the first sub-electrode tab and the second sub-electrode tab; The negative electrode plate has a first side and a second side adjacent to each other, and the second electrode tab includes a third sub-pole tab and a fourth sub-pole tab; the third sub-pole tab is provided on the first side of the negative electrode plate, and the fourth sub-pole tab is provided on the second side of the negative electrode plate, and the second pin member connects the third sub-pole tab and the fourth sub-pole tab.

3. The pole piece connection assembly according to claim 2, characterized in that: The first sub-tab is provided with a first pre-welding area, the second sub-tab is provided with a second pre-welding area, the third sub-tab is provided with a third pre-welding area, and the fourth sub-tab is provided with a fourth pre-welding area; The first end of the first pin component is arranged in the first pre-welding area, and the second end of the first pin component is arranged in the second pre-welding area; the first end of the second pin component is arranged in the third pre-welding area, and the second end of the second pin component is arranged in the fourth pre-welding area.

4. The pole piece connection assembly according to claim 3, characterized in that: A first final welding area is provided in the first pre-welding area, a second final welding area is provided in the second pre-welding area, a third final welding area is provided in the third pre-welding area, and a fourth final welding area is provided in the fourth pre-welding area; The first end of the first lead is connected to the first terminal welding area, and the second end of the first lead is connected to the second terminal welding area; the first end of the second lead is connected to the third terminal welding area, and the second end of the second lead is connected to the fourth terminal welding area; The area of ​​the first pre-welding region is larger than the area of ​​the first final welding region, the area of ​​the second pre-welding region is larger than the area of ​​the second final welding region, the area of ​​the third pre-welding region is larger than the area of ​​the third final welding region, and the area of ​​the fourth pre-welding region is larger than the area of ​​the fourth final welding region.

5. The pole piece connection assembly according to claim 4, characterized in that: The area ratio of the first pre-welding region to the first final welding region is 1.8:1 to 2.2:1, the area ratio of the second pre-welding region to the second final welding region is 1.8:1 to 2.2:1, the area ratio of the third pre-welding region to the third final welding region is 1.8:1 to 2.2:1, and the area ratio of the fourth pre-welding region to the fourth final welding region is 1.8:1 to 2.2:

1.

6. The pole piece connection assembly according to claim 3, characterized in that: The first pre-welding region is disposed near a bottom edge of the first sub-tab, where the bottom edge of the first sub-tab is away from the second sub-tab; the second pre-welding region is disposed near a bottom edge of the second sub-tab, where the bottom edge of the second sub-tab is away from the first sub-tab; The third pre-welding area is arranged close to the bottom edge of the third sub-pole lug, and the bottom edge of the third sub-pole lug is the side away from the fourth sub-pole lug; the fourth pre-welding area is arranged close to the bottom edge of the fourth sub-pole lug, and the bottom edge of the fourth sub-pole lug is the side away from the third sub-pole lug.

7. The pole piece connection assembly according to claim 6, characterized in that: The distance from the center of the first pre-welding area to the bottom edge of the first sub-tab is less than or equal to one-third of the distance from the bottom edge of the first sub-tab to the top edge of the first sub-tab; The distance from the center of the second pre-welding area to the bottom edge of the second sub-electrode tab is less than or equal to one-third of the distance from the bottom edge of the second sub-electrode tab to the top edge of the second sub-electrode tab; The distance from the center of the third pre-welding area to the bottom edge of the third sub-electrode tab is less than or equal to one-third of the distance from the bottom edge of the third sub-electrode tab to the top edge of the third sub-electrode tab; The distance from the center of the fourth pre-welding area to the bottom edge of the fourth sub-tab is less than or equal to one third of the distance from the bottom edge of the fourth sub-tab to the top edge of the fourth sub-tab.

8. The pole piece connection assembly according to claim 2, characterized in that: The ratio of the length of the positive electrode plate to the length of the first sub-electrode tab is 3.2:1 to 3.4:1, and the ratio of the width of the positive electrode plate to the length of the second sub-electrode tab is 2.0:1 to 2.2:1; The ratio of the length of the negative electrode plate to the length of the third sub-electrode tab is 3.3:1 to 3.5:1, and the ratio of the width of the negative electrode plate to the length of the fourth sub-electrode tab is 2.1:1 to 2.3:

1.

9. The pole piece connection assembly according to claim 2, characterized in that: The ratio of the long side to the short side of the first sub-tab is 8.4:1 to 8.8:1, and the ratio of the long side to the short side of the second sub-tab is 1.6:1 to 2.1:1; The ratio of the long side to the short side of the third sub-tab is 8.4:1 to 8.8:1, and the ratio of the long side to the short side of the fourth sub-tab is 1.6:1 to 2.1:

1.

10. The pole piece connection assembly according to claim 3, characterized in that: The first pin member includes a first pin segment and a second pin segment; the first end of the first pin segment is connected to the first end of the second pin segment; the second end of the first pin segment is provided with a first connecting portion, and the second end of the second pin segment is provided with a second connecting portion; the first sub-electrode tab is provided with a first bending portion, and the second sub-electrode tab is provided with a second bending portion; the first connecting portion is plugged into the first bending portion, and the second connecting portion is plugged into the second bending portion; the first pin segment and the second pin segment form a first preset angle; The second pin component includes a third pin segment and a fourth pin segment; the first end of the third pin segment is connected to the first end of the fourth pin segment; the second end of the third pin segment is provided with a third connecting portion, and the second end of the fourth pin segment is provided with a fourth connecting portion; the third sub-pole ear is provided with a third bending portion, and the fourth sub-pole ear is provided with a fourth bending portion; the third connecting portion is plugged into the third bending portion, and the fourth connecting portion is plugged into the fourth bending portion; the third pin segment and the fourth pin segment form a second preset angle.

11. The pole piece connection assembly according to claim 10, characterized in that: The first connecting portion protrudes from the first lead segment along a width direction of the first lead segment, and the second connecting portion protrudes from the second lead segment along a width direction of the second lead segment; And / or, the third connection portion protrudes from the third lead segment along the width direction of the third lead segment, and the fourth connection portion protrudes from the fourth lead segment along the width direction of the fourth lead segment.

12. The pole piece connection assembly according to claim 10, characterized in that: The second end of the second lead segment is provided with at least two second connecting portions, and a first hollow gap is formed between two adjacent second connecting portions; And / or, the second end of the fourth pin segment is provided with at least two fourth connecting portions, and a second hollow gap is provided between two adjacent fourth connecting portions.

13. The pole piece connection assembly according to claim 10, characterized in that: The second end of the first lead segment is provided with at least two first connecting portions, and two adjacent first connecting portions are closed. And / or, the second end of the third pin segment is provided with at least two third connecting portions, and two adjacent third connecting portions are closed.

14. The pole piece connection assembly according to claim 10, characterized in that: The first pin segment and / or the second pin segment is provided with a plurality of first weight-reducing through holes; The third pin segment and / or the fourth pin segment is provided with a plurality of second weight-reducing through holes.

15. The pole piece connection assembly according to any one of claims 1 to 14, characterized in that: The negative electrode sheet and the positive electrode sheet are stacked, the long side of the negative electrode sheet protrudes beyond the long side of the positive electrode sheet, and the protruding distance of the long side is 5 to 6 mm; the short side of the negative electrode sheet protrudes beyond the short side of the positive electrode sheet, and the protruding distance of the short side is 6 to 7 mm.

16. The pole piece connection assembly according to any one of claims 1 to 14, characterized in that: It also includes a first insulating member and a second insulating member; the first insulating member is arranged to cover the connection between the first pin member and the first tab; the second insulating member is arranged to cover the connection between the second pin member and the second tab.

17. The pole piece connection assembly according to any one of claims 1 to 14, characterized in that: A separator is stacked between the adjacent positive electrode sheets and the adjacent negative electrode sheets; The long side of the diaphragm protrudes from the long side of the negative electrode sheet, and the protruding distance of the long side is 5 to 6 mm; the short side of the diaphragm protrudes from the short side of the negative electrode sheet, and the protruding distance of the short side is 6 to 7 mm.

18. The pole piece connection assembly according to claim 16, characterized in that: The ratio of the area of ​​the first insulating member to the area of ​​the first tab is 1.4:1 to 1.6:1; The ratio of the area of ​​the second insulating member to the area of ​​the second tab is 1.4:1 to 1.6:

1.

19. A battery, characterized in that: It comprises a diaphragm and a pole piece connection assembly as claimed in any one of claims 1 to 18; the diaphragm is stacked between adjacent positive pole pieces and negative pole pieces.

20. The battery according to claim 19, characterized in that Also included is a cover plate, the cover plate being provided with a positive electrode post and a negative electrode post; The first pin is connected to the positive electrode post, and the second pin is connected to the negative electrode post.

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