Main body of rechargeable cylindrical battery
By sandwiching an insulating isolation matrix between the current collecting plate and the bottom of the shell of the lithium-ion cylindrical battery, welding is only performed at some positions, solving the problems of small welding area and cold welding, and improving welding reliability and the battery's vibration resistance.
Patent Information
- Application Number
- CN202421685102.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-16
- Publication Date
- 2025-10-03
- Estimated Expiration
- 2034-07-16
AI Technical Summary
The welding area between the collector plate and the steel shell of existing lithium-ion cylindrical batteries is small, which makes it easy for circuits to break during vibration, and it is easy for cold welds and current shunts to occur during welding, making it difficult to meet market demand.
An insulating isolation matrix is sandwiched between the collecting plate and the shell bottom. Only part of the isolation matrix is welded to the shell bottom, and the rest of the collecting plate is insulated and separated from the shell bottom. Through holes and extensions are designed to enhance welding reliability.
It reduces the occurrence of cold solder joints, improves the reliability and stability of welding, ensures local overcurrent, and enhances the battery's anti-vibration ability.
Smart Images
Figure CN223414236U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to a battery used as power, in particular to a main body of a rechargeable cylindrical battery. Background Art
[0002] With the vigorous development of the new energy industry, it provides a huge market for the battery industry, thereby accelerating the pace of development of the battery industry.
[0003] Currently, lithium-ion cylindrical batteries are becoming a mainstream product in the new energy industry due to their advantages such as high energy density, increased charge and discharge rates, and good capacity consistency. As full-tab / collector trays have been identified as the preferred cylindrical battery structure by more and more manufacturers, the welding of the collector tray to the bottom of the steel shell has become more important. However, common problems are as follows:
[0004] (1) The collecting plate and the bottom of the steel shell are welded together by resistance welding. Due to the matching problem, the welding area is small, which makes it easy to break the circuit during vibration, making it difficult to meet the current market demand.
[0005] (2) After the collecting plate is welded to the foil, it is easily squeezed by the winding core, causing the collecting plate to fit the steel shell. When the collecting plate and the bottom of the steel shell are welded by resistance welding, a shunt effect occurs between the collecting plate and the steel shell, resulting in a cold weld.
[0006] Therefore, there is an urgent need for a main body of a rechargeable cylindrical battery to overcome one or more of the above-mentioned drawbacks. Utility Model Content
[0007] The utility model aims to provide a main body of a rechargeable cylindrical battery, which ensures local overcurrent and reduces the occurrence of cold welding during welding.
[0008] To achieve the aforementioned objectives, the main body of the rechargeable cylindrical battery of the present invention comprises a housing, a winding core, a current collecting tray, and an insulating separator. The winding core and current collecting tray are located within the housing. The current collecting tray is positioned between the winding core and the housing bottom in the height direction of the housing. The current collecting tray is welded to the tabs in the winding core. The separator comprises an insulating substrate sandwiched between the current collecting tray and the housing bottom. The insulating substrate partially covers the current collecting tray. The current collecting tray, where it is exposed from the insulating substrate, has a welded portion to the housing bottom.
[0009] Compared with the prior art, the main body of the rechargeable cylindrical battery of the present invention also includes an insulating separator, which includes an insulating matrix sandwiched between the current collecting disc and the shell bottom. The insulating matrix partially covers the current collecting disc, and the current collecting disc has a welding portion welded to the shell bottom at the position exposed from the insulating matrix. This design ensures that the current collecting disc is welded to the shell bottom only at the welding portion, and the other positions of the current collecting disc are insulated and separated from the shell bottom by the insulating matrix, thereby ensuring local overcurrent and reducing the occurrence of cold welds during the welding process.
[0010] Preferably, the isolation base is provided with a through hole which is arranged through the shell in the height direction, and the welding portion passes through the isolation base through the through hole.
[0011] Preferably, the isolation base further protrudes laterally from the current collecting plate, and the through hole is located at the center of the isolation base.
[0012] Preferably, the isolation body further includes an extension body extending from the outer edge of the isolation base along the height direction of the shell, the extension body is located between the side wall of the shell and the winding core, and the extension body is also arranged around the winding core.
[0013] Preferably, the shell bottom includes an outer ring base and a sunken inner ring portion sunken relative to the outer ring base, the outer ring base supports the isolation base from below, and the welding portion is welded to the sunken inner ring portion.
[0014] Preferably, the isolation substrate is in sheet form.
[0015] Preferably, the collecting plate includes a collecting plate body and a bent body bent downward from the end of the collecting plate body, the bent body is arranged in layers at a certain distance from the collecting plate body in the height direction of the shell, the bent body is passed through the through hole, and the welding portion is formed on the bent body.
[0016] Preferably, the bent body includes a first bent body bent downward from the end of one side of the collecting plate body and a second bent body bent downward from the end of the other side of the collecting plate body, the second bent body is bent below the first bent body, and the second bent body is also partially stacked with the first bent body, and the welding portion is formed on the second bent body.
[0017] Preferably, the collecting plate body is provided with a through hole which is arranged to penetrate the shell in the height direction, and the first bent body is arranged opposite to the through hole in the height direction of the shell.
[0018] Preferably, the center of the winding core has a central channel, and the central channel is arranged opposite to the through hole in the height direction of the shell. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] Figure 1 It is a three-dimensional diagram of the main body of the cylindrical rechargeable battery of the present utility model.
[0020] Figure 2 yes Figure 1 The main body of the cylindrical rechargeable battery is shown in a plan view as viewed from the direction opposite to that indicated by arrow A.
[0021] Figure 3 It is along Figure 2 Internal view cut along the midline BB.
[0022] Figure 4 yes Figure 3 Internal view of the housing.
[0023] Figure 5 It is a three-dimensional diagram of the current collecting disk in the main body of the cylindrical rechargeable battery of the present invention before being welded to the winding core and the shell bottom.
[0024] Figure 6 yes Figure 5 The collecting plate is shown in a plan view along the direction indicated by the arrow above it.
[0025] Figure 7 yes Figure 5 Floor plan viewed from top to bottom.
[0026] Figure 8 It is along Figure 7 Stereoscopic internal view cut along the CC line.
[0027] Figure 9 yes Figure 3 A stereogram of the isolator in FIG.
[0028] Figure 10 Yes Figure 3 Internal image of the deformation.
[0029] Figure 11 yes Figure 10 A three-dimensional view of another embodiment of an insulator in FIG. DETAILED DESCRIPTION
[0030] Embodiments of the present invention will now be described with reference to the accompanying drawings, wherein like reference numerals represent like elements throughout the drawings.
[0031] See also Figures 1 to 3The main body 100 of the rechargeable cylindrical battery of the present invention includes a shell 10, a winding core 20, a current collecting plate 30 and an insulating separator 40. Optionally, as an example, the shell 10 is a steel shell so that the shell 10 has sufficient pressure resistance. In addition, the shell 10 is a circular shell so that the main body 100 of the rechargeable cylindrical battery of the present invention has a cylindrical shape. Obviously, according to actual needs, the shell 10 can also be other metal shells. At the same time, the shape of the shell 10 can also be square, etc. This is well known in the art and will not be described in detail here.
[0032] At the same time, the core 20 is located in the shell 10. Optionally, as an example, the core 20 is a winding core so that there is a central channel 21 at the center of the core 20. Therefore, before the collecting plate 30 is welded to the shell bottom 11 of the shell 10, the external ejector pin can follow the central channel 21 of the core 20 to the position of pushing the collecting plate 30, so that the shell bottom 11 of the shell 10 and the collecting plate 30 are kept in a state of pressure by pushing, thereby avoiding the operation mode of keeping the shell bottom 11 of the shell 10 and the collecting plate 30 in a state of pressure by pushing the core 20; obviously, according to actual needs, the core 20 can also be made into a folding core, so it is not necessary to Figure 1 and Figure 2 Limits shown.
[0033] Furthermore, the collecting plate 30 is located inside the housing 10, and the collecting plate 30 is also located between the winding core 20 and the bottom 11 of the housing 10 in the height direction of the housing 10 (see the direction indicated by the arrow A). Figure 3 As shown; the collecting disc 30 is also welded to the tabs in the winding core 20, such as but not limited to full tab welding. The isolating body 40 includes an isolating base 41 sandwiched between the collecting disc 30 and the shell bottom 11, the isolating base 41 partially covers the collecting disc 30, and the current collecting disc 30 has a welding portion 31 welded to the shell bottom 11 at the position exposed from the isolating base 41; with the help of the isolating base 41, the other positions of the collecting disc 30 except the welding portion 31 are insulated and separated, thereby ensuring local overcurrent. It should be noted that since the isolating base 41 is sandwiched between the collecting disc 30 and the shell bottom 11, the isolating base 41 partially covers the collecting disc 30 from the bottom of the collecting disc 50, and accordingly, the position of the collecting disc 30 not covered by the isolating base 41 is naturally exposed downward. More specifically, as follows:
[0034] like Figure 3 As shown, as an example, the isolation base 41 is provided with a through hole 411 arranged in the height direction of the shell 10, and the welding portion 31 passes through the isolation base 41 from the through hole 411, so that the welding portion 31 is welded with the shell bottom 11 of the shell 10; Figure 3As an example, the isolation base 41 also protrudes laterally from the current collecting plate 30, providing more reliable insulation and isolation for the current collecting plate 30 other than the weld 31, preventing these other locations from accidentally contacting the housing bottom 11. Furthermore, the through hole 411 is located at the center of the isolation base 41. This design makes the arrangement of the through hole 411 and the weld 31 more rational and compact. It should be noted that the lateral direction here refers to the direction perpendicular to the height direction of the housing 10. Therefore, when the housing 10 is circular, the lateral direction is the radial direction of the circle.
[0035] Combine Figure 3 and Figure 9 As an example, the isolating body 40 further includes an extension body 42 extending from the outer edge of the isolating base 41 along the height direction of the housing 10. The extension body 42 is located between the side wall 12 of the housing 10 and the winding core 20, and the extension body is also arranged around the winding core 20. With the help of the extension body 42, the winding core 20 and the side wall 12 of the housing 10 are insulated and separated from each other from the side, thereby further reducing the effect of cold soldering. Specifically, Figure 9 In the figure, the isolation substrate 41 is sheet-shaped; in addition, the isolation substrate 41 and the extension 42 are both annular to better match the winding core 20 obtained by the winding method. Obviously, according to actual needs, the shape of the isolation substrate 41 and the extension 42 can also be other, so it is not Figure 9 Limits shown.
[0036] like Figure 3 and Figure 4 As shown, as an example, the shell bottom 11 includes an outer ring base 111 and a sunken inner ring portion 112 that is sunken relative to the outer ring base 111. The outer ring base 111 supports the isolation base 41 from below, and the welding portion 31 is welded to the sunken inner ring portion 112. This design can provide sufficient space for the multi-layer design of the collecting plate 30. Specifically, Figure 3 、 Figure 6 and Figure 8As an example, the collecting plate 30 includes a collecting plate body 30a and a bent body 30b bent downward from the end of the collecting plate body 30a; the bent body 30b is arranged in a layered manner at a certain distance from the collecting plate body 30a in the height direction of the housing 10, the bent body 30b is inserted into the through hole 411, and the welding portion 31 is formed on the bent body 30b; such a design allows the collecting plate 30 to be manufactured by bending, so when the collecting plate 30 is made of a composite material, for example, When the upper layer 30a1 of the collecting plate 30 is a copper layer and the lower layer 30a2 of the collecting plate 30 is a nickel layer, the upper layer 30a1 of the collecting plate body 30a is made of the same material as the bottom layer of the bent body 30b, and the bottom layer 30a2 of the collecting plate body 30a is made of the same material as the top layer of the bent body 30b by bending. This makes the welding of the welding portion 31 to the shell bottom 11 more reliable and prevents the defects of the copper layer sticking to the needle and the high reflection phenomenon during laser welding. More specifically, Figure 3 、 Figure 6 and Figure 8 As an example, the bent body 30b includes a first bent body 30b1 bent downward from the end of one side of the current collecting disc body 30a and a second bent body 30b2 bent downward from the end of the other side of the current collecting disc body 30a. The second bent body 30b2 is bent below the first bent body 30b1. The second bent body 30b2 is also partially stacked with the first bent body 30b1, and the welding portion 31 is formed on the second bent body 30b2. The purpose of this design is that when the battery is manufactured after welding, the first bent body 30b1 and the second bent body 30b2 pass current at the same time, so the effect of passing current is better. Optionally, Figure 3 、 Figure 7 and Figure 8 As an example, the collecting plate body 30a is provided with a through hole 32 arranged in the height direction of the housing 10, and the first bent body 30b1 is arranged opposite to the through hole 32 in the height direction of the housing 10. For example, the first bent body 30b1 partially covers the through hole 32 from the bottom of the collecting plate body 30a, so that the uncovered portion of the through hole 32 is shown as numeral 321. Figure 7 Obviously, according to actual needs, the first bent body 30b1 can also completely cover the through hole 32 from the bottom of the collecting plate body 30a, so it is not seen Figure 7 The illustration is limited. Furthermore, when the winding core 20 has a central channel 21, the central channel 21 is arranged relative to the through-hole 32 in the height direction of the housing 10, for example but not limited to alignment, to allow an external ejector pin to follow the central channel 21 to the through-hole 32, then pass through the through-hole 32 to push the first bent body 30b1. The through-hole 32 defined by the collecting plate body 30a serves two primary functions:
[0037] First, since the current collecting plate 30 includes the collecting plate body 30a, the first bent body 30b1 and the second bent body 30b2, the collecting plate 30 has a three-layer structure. Therefore, during the welding process, the ejector pin entering from the outside along the central channel 21 is pressed against the first bent body 30b1 through the through hole 32, thereby pressing the second bent body 30b2 against the shell bottom 11 through the first bent body 30b1, so that the shell bottom 11 and the second bent body 30b2 are welded together, and the first bent body 30b1 and the second bent body 30b2 are welded together; thereby avoiding the defect of cold welding due to the three-layer structure of the current collecting plate 30 being too thick.
[0038] Secondly, when the ejector pin is made of the same material as the upper layer 30a1 of the collecting plate body 30a, the through hole 32 allows the ejector pin to push against the top layer of the bent first body 30b1, and the material of the top layer of the first bent body 30b1 is actually formed by the bottom layer 30a2 of the collecting plate body 30a. Therefore, the material of the ejector pin is different from the material of the top layer of the first bent body 30b1 pushed by the ejector pin, thereby effectively preventing the defect of material sticking to the needle (i.e., the ejector pin) during welding.
[0039] See also Figure 10 and Figure 11 , it is right Figure 3 Another embodiment of deforming the isolator in the embodiment. Figure 10 and Figure 11 In the embodiment, the isolator 40' only includes the isolator body 41. Figure 3 and Figure 9 In the embodiment, the isolating body 40 includes an isolating body 41 and an extending body 42. Except for the above differences, the other two are the same, so they will not be described here in detail.
[0040] Compared with the prior art, since the main body 100 of the rechargeable cylindrical battery of the present invention also includes an insulating separator 40 (40'), the separator 40 (40') includes an isolation base 41 sandwiched between the current collecting plate 30 and the shell bottom 11, the isolation base 41 partially covers the current collecting plate 30, and the current collecting plate 30 has a welding portion 31 welded to the shell bottom 11 at the position exposed from the isolation base 41. This design ensures that the current collecting plate 30 is only welded to the shell bottom 11 at the welding portion 31, and the other positions of the current collecting plate 30 are insulated and separated from the shell bottom 11 by the isolation base 41, thereby ensuring local overcurrent, and thus reducing the occurrence of cold welds during the welding process.
[0041] It is worth noting that the main body 100 of the rechargeable cylindrical battery of the present invention is further equipped with a cover, an explosion-proof valve and an electrolyte to form a complete battery product. In addition, the aforementioned winding core refers to a core made by winding, and the aforementioned folding core refers to a core made by folding. In addition, the shape of the collecting plate 30 is not limited to a disc shape, and can be a strip shape according to actual needs. Finally, Figure 6 and Figure 8 In the figure, although there is a certain gap between the first bent body 30b1 and the second bent body 30b2, this is before the collecting plate 30 is welded to the shell bottom 11. However, during the welding process, due to the top pressure of the top needle on the first bent body 30b1, the first bent body 30b1 and the second bent body 30b2 are pressed against the shell bottom 11, so that the first bent body 30b1 and the second bent body 30b2 are welded together by resistance welding, and the second bent body 30b2 is welded to the shell bottom 11. Therefore, after welding, there is no gap between the first bent body 30b1 and the second bent body 30b2. Figure 6 and Figure 8 The gap shown in .
[0042] The above disclosure is only a preferred embodiment of the present invention, and certainly cannot be used to limit the scope of rights of the present invention. Therefore, equivalent changes made according to the scope of the patent application of the present invention are still within the scope covered by the present invention.
Claims
1. A main body of a rechargeable cylindrical battery, comprising a housing, a winding core and a current collecting plate located within the housing, wherein the current collecting plate is located between the winding core and the bottom of the housing in the height direction of the housing, and the current collecting plate is welded to the tab in the winding core, characterized in that: The main body of the rechargeable cylindrical battery further includes an insulating separator, which includes an insulating base sandwiched between the current collecting disc and the shell bottom. The insulating base partially covers the current collecting disc, and the current collecting disc has a welding portion welded to the shell bottom at a position exposed from the insulating base.
2. The main body of the rechargeable cylindrical battery according to claim 1, characterized in that: The isolation base is provided with a through hole which is arranged to penetrate the shell in the height direction, and the welding portion passes through the isolation base through the through hole.
3. The main body of the rechargeable cylindrical battery according to claim 2, characterized in that: The isolation base further protrudes laterally from the current collecting plate, and the through hole is located at the center of the isolation base.
4. The main body of the rechargeable cylindrical battery according to claim 1, characterized in that: The isolation body further includes an extension body extending from the outer edge of the isolation base along the height direction of the shell. The extension body is located between the side wall of the shell and the winding core, and the extension body is also arranged around the winding core.
5. The main body of the rechargeable cylindrical battery according to claim 1, characterized in that: The shell bottom includes an outer ring base and a sunken inner ring portion that is sunken relative to the outer ring base. The outer ring base supports the isolation base from below, and the welding portion is welded to the sunken inner ring portion.
6. The main body of the rechargeable cylindrical battery according to claim 1, characterized in that: The isolation substrate is in sheet shape.
7. The main body of the rechargeable cylindrical battery according to claim 2, characterized in that: The collecting plate includes a collecting plate body and a bent body bent downward from the end of the collecting plate body. The bent body is arranged in layers at a certain distance from the collecting plate body in the height direction of the shell. The bent body is inserted into the through hole, and the welding portion is formed on the bent body.
8. The main body of the rechargeable cylindrical battery according to claim 7, characterized in that: The bent body includes a first bent body bent downward from the end of one side of the collecting plate body and a second bent body bent downward from the end of the other side of the collecting plate body. The second bent body is bent below the first bent body, and the second bent body is also partially stacked with the first bent body. The welding portion is formed on the second bent body.
9. The main body of the rechargeable cylindrical battery according to claim 8, characterized in that: The collecting plate body is provided with a through hole which is arranged to penetrate the shell in the height direction, and the first bent body is arranged opposite to the through hole in the height direction of the shell.
10. The main body of the rechargeable cylindrical battery according to claim 1, characterized in that: The center of the winding core has a central channel, and the central channel is arranged opposite to the through hole in the height direction of the shell.