Cylindrical roll core with same-side tabs, roll core preparation equipment and battery

Abstract

The utility model provides a cylindrical roll core with tabs on the same side, roll core preparation equipment and a battery, and relates to the technical field of lithium ion batteries, the end face on the same side of the cylindrical roll core is provided with a positive pole tab area and a negative pole tab area, and the negative pole tab in the negative pole tab area is provided with salient points; and the top of the salient point is flush with the top of a positive pole lug arranged in the positive pole lug area. The cylindrical roll core has the beneficial effects that the convex points on the negative pole lug of the cylindrical roll core can increase the height of the negative pole lug, so that the negative pole lug is matched with the positive pole lug in height, and the heights of the end surfaces of the positive pole lug and the negative pole lug can be kept consistent after a leveling process. The height consistency of the end surfaces of the flatted tabs can be more easily controlled; meanwhile, the height and the compactness of the tabs are better controlled, and the subsequent welding process is more stable and reliable, so that the overall production yield is improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to lithium ion battery technical field especially relates to a cylindrical winding core of the same side of pole lug, winding core preparation equipment and battery. BACKGROUND

[0002] Cylindrical lithium ion battery is widely used in mobile phone, tablet computer, wearable device, mobile power, electric tool and energy storage system and many other fields because of high energy density and superior cycle performance. The winding core design of traditional cylindrical lithium ion battery usually adopts the form of two-end pole lug, whether single pole lug, multiple pole lug or full pole lug, all rely on the shell as the flow body, which not only increases the battery internal resistance, reduces the energy conversion efficiency, but also increases the cost. The positive and negative pole lug concentrated area is formed at one end of the winding core, and this structure significantly reduces the battery resistance and significantly improves the electrochemical performance of the battery.

[0003] In the prior art, for the cylindrical battery with positive and negative pole lugs on the same side, the positive current collector adopts aluminum foil, and the negative current collector adopts copper foil. Due to the different thicknesses of the two, the heights of the positive and negative pole lugs after superposition are inconsistent. During the pole lug flattening process, it is difficult to control the consistency of the end face height of the positive and negative pole lugs after flattening, and the flattening density of the pole lug cannot be guaranteed, which adversely affects the subsequent welding process and overall production yield. SUMMARY

[0004] In view of the problems existing in the prior art, the utility model provides a cylindrical winding core with pole lugs on the same side, the same side end face of the cylindrical winding core is provided with a positive pole lug area and a negative pole lug area, the negative pole lug in the negative pole lug area has a protrusion, and the top of the protrusion is flush with the top of the positive pole lug provided in the positive pole lug area.

[0005] Preferably, the center of the cylindrical winding core has a center hole, and the positive pole lug area and the negative pole lug area are symmetrically distributed about the center hole.

[0006] Preferably, the positive pole lug area and the negative pole lug area further include a low pole lug area therebetween.

[0007] Preferably, the height of the protrusion is 2-50 microns.

[0008] Preferably, the protrusion is a circular protrusion.

[0009] The utility model also provides a winding core preparation equipment, which comprises:

[0010] A knurling piece, a laser cutting piece, a winding piece and a flattening piece are sequentially arranged along the direction of conveying the to-be-embossed pole piece.

[0011] The embossing member is used for embossing the tab area of the to-be-embossed pole piece to form protrusions to obtain an embossed pole piece.

[0012] The laser cutting member is used for laser cutting the tab area of the embossed pole piece to obtain a negative pole piece.

[0013] The winding member is used for winding the negative pole piece and the positive pole piece into a winding core, and the flattening member is used for flattening the negative tab and the positive tab of the winding core to obtain the cylindrical winding core as described above.

[0014] Preferably, the embossing member comprises:

[0015] A soft roller on which the to-be-embossed pole piece is wound;

[0016] An embossing roller arranged on one side of the soft roller and corresponding to the tab area of the to-be-embossed pole piece;

[0017] A pneumatic cylinder used for pushing the embossing roller towards the soft roller.

[0018] Preferably, the depth of the pattern on the embossing roller is 2-50 microns.

[0019] Preferably, the shape of the protrusion pattern on the embossing roller is circular.

[0020] The utility model also provides a battery comprising the cylindrical winding core.

[0021] The above technical solution has the following advantages or beneficial effects:

[0022] The protrusions on the negative tab of the cylindrical winding core can increase the height of the negative tab, so that the height of the negative tab matches the height of the positive tab, and the end face height of the positive and negative tabs can be kept consistent after the flattening process. The end face height consistency of the flattened tabs can be more easily controlled; at the same time, since the height and density of the tabs are better controlled, the subsequent welding process will also be more stable and reliable, thereby improving the overall production yield. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 In a preferred embodiment of the utility model, a top view of the cylindrical winding core with tabs on the same side;

[0024] Figure 2 In a preferred embodiment of the utility model, a sectional view of the cylindrical winding core with tabs on the same side;

[0025] Figure 3 In a preferred embodiment of the utility model, a structural schematic view of a winding core preparation device. DETAILED DESCRIPTION

[0026] The utility model is not limited to the embodiment, and other embodiments can also belong to the scope of the utility model as long as they meet the main idea of the utility model.

[0027] In the preferred embodiment of the utility model, based on the above problems existing in the prior art, a cylindrical core with tabs on the same side is provided, as shown in Figure 1 and Figure 2 The same side end surface of the cylindrical core 1 is provided with a positive tab area 11 and a negative tab area 12. The negative tab 121 in the negative tab area 12 has a protrusion on the top, and the top of the protrusion is flush with the top of the positive tab 111 provided in the positive tab area 11.

[0028] Specifically, the embodiment provides a cylindrical core with tabs on the same side. On the same side end surface of the cylindrical core 1, a positive tab area 11 and a negative tab area 12 are respectively provided. This partition design helps better manage and control the position and height of the positive and negative tabs during the manufacturing process. This structure can solve the design and manufacturing problems caused by the positive and negative tabs being on the same side.

[0029] Further, by providing a protrusion on the negative tab 121, the thickness of the negative tab can be artificially increased to match the height of the positive tab. The design and size of the protrusion can be accurately calculated to ensure that the end surface height of the positive and negative tabs remains consistent after the flattening process.

[0030] Since the height of the positive and negative tabs is matched, the difficulty of the flattening process is greatly reduced, and the end surface height consistency of the tabs after flattening can be more easily controlled. At the same time, since the height and density of the tabs are better controlled, the subsequent welding process will also be more stable and reliable, thereby improving the overall production yield.

[0031] In the preferred embodiment of the utility model, the cross-sectional center of the cylindrical core 1 has a center hole 13, and the positive tab area 11 and the negative tab area 12 are symmetrically distributed about the center hole 13.

[0032] Further, the embodiment includes a low tab area 14 between the positive tab area 11 and the negative tab area 12.

[0033] Specifically, in the embodiment, the positive tab area 11 and the negative tab area 12 are symmetrically distributed about the center hole 13. This design makes the cylindrical core 1 more balanced in structure, which helps to reduce stress concentration caused by uneven distribution of tabs, thereby improving the overall structural stability and safety of the battery.

[0034] The symmetrical distribution of the tab regions also helps the current flow more uniformly inside the battery, reducing problems such as performance degradation or local overheating caused by uneven current distribution.

[0035] The addition of the low tab region 14 between the positive tab region 11 and the negative tab region 12 can make more effective use of the end face space of the cylindrical core. This design not only helps to reduce the interference between the tabs, but also provides more possibilities for the arrangement of other components such as temperature sensors, safety valves, etc.

[0036] The setting of the low tab region 14 can also improve the heat dissipation performance of the battery to some extent. Since the tab is one of the main areas of heat generation inside the battery, by optimizing the layout and distribution of the tab, the local temperature of the tab area can be reduced, thereby improving the overall thermal stability and safety of the battery.

[0037] Specifically, in the present embodiment, the thickness-consistent negative tab 121 and positive tab 111 can control the consistency of the end face height after tab flattening during the tab flattening process, and the tab flattening density can also be guaranteed. The subsequent welding process will also be more stable and reliable, thereby improving the overall production yield.

[0038] In a preferred embodiment of the present application, the height of the protrusions is 2-50 microns.

[0039] In a preferred embodiment of the present application, the protrusions are circular protrusions.

[0040] Specifically, in the present embodiment, the circular protrusions have a smooth shape and have less impact on the tabs during the manufacturing process. They will not cause cracking or belt breaking of the tabs due to piercing the tabs, and the embossing strength retention rate is high. The height range can be adjusted between 2-50 microns, which can meet the thickness difference of most positive and negative tabs.

[0041] The present application also provides a core preparation equipment, as shown in Figure 3 The present application also provides a core preparation equipment, as shown in

[0042] The embossing member 100, the laser cutting member 200, the winding member 300, and the flattening member are sequentially arranged along the conveying direction of the to-be-embossed tab;

[0043] The embossing member 100 is used for embossing the tab region 401 of the to-be-embossed tab 400 to obtain an embossed tab 500;

[0044] The laser cutting member 200 is used for laser cutting the tab region of the embossed tab 500 to obtain a negative tab 600;

[0045] The winding piece 300 is used for winding the negative electrode sheet 600 and the positive electrode sheet 700 into a core, and the flattening piece is used for flattening the negative electrode tabs and the positive electrode tabs of the core to obtain the cylindrical core 1 as described above.

[0046] Specifically, the present embodiment provides a core preparation device for preparing the aforementioned cylindrical core, in which the embossed electrode sheet 400 is sequentially subjected to embossing treatment, tab laser cutting and winding process in the device to finally obtain the cylindrical core 1 with the tabs on the same side, and the positive and negative electrode tabs are flattened from the vertical state (before flattening) to the horizontal state by flattening, thereby meeting the process requirements for preparing the aforementioned cylindrical core. Figure 2

[0047] The utility model also provides a battery comprising the aforementioned cylindrical core.

[0048] Subsequently, the current collector plate is placed on the welding tool clamp, and the cylindrical core is vertically placed on the current collector plate for welding, and finally the cylindrical core, the positive and negative electrode posts and the shell are welded to obtain the battery provided by the utility model.

[0049] In the preferred embodiment of the utility model, as shown in Figure 3 The embossing piece 100 comprises:

[0050] The soft roller 110 has the embossed electrode sheet 400 wound thereon;

[0051] The embossing roller 120 is arranged on one side of the soft roller 100 and corresponds to the tab area 410 of the embossed electrode sheet 400;

[0052] The cylinder is used for pushing the embossing roller towards the soft roller.

[0053] Specifically, in the present embodiment, the embossing treatment refers to the extrusion force generated by the cylinder driving the embossing roller, and the process comprises:

[0054] By adjusting the cylinder pressure, adjusting the extrusion gap between the embossing roller and the soft roller, and generating different pits on the electrode sheet foil, a plurality of convex points are formed.

[0055] Further, the tab laser cutting is performed:

[0056] The positive and negative electrode tab distribution mode is two symmetrical fan-shaped areas, and the laser cutting of the embossed electrode sheet can adopt the prior art, as shown in Figure 3 Each negative electrode tab on the negative electrode sheet after laser cutting has a certain spacing, and the spacing is calculated according to the Archimedes spiral formula, and then cutting is performed, and this part can adopt the prior art, and will not be described in detail.

[0057] ​In the preferred embodiment of the utility model, the depth of the embossed lines of the embossing roller is 2-50 microns.

[0058] In the preferred embodiment of the utility model, the shape of the embossed lines on the embossing roller is circular.

[0059] Specifically, in the embodiment, because the thickness of the positive and negative tabs is inconsistent (for example, 13 microns for the positive tab and 6 microns for the negative tab), the depth of the embossing is in the range of 2-50 microns, and accordingly, the depth of the embossed lines on the embossing roller is also generally in the range of 2-50 microns; the diameter is between 2-50 microns. In addition, the shape of the embossed lines on the embossing roller is circular, which is smooth in shape and has less impact on the tabs, and will not cause the tabs to be pierced, resulting in cracking of the tabs, breaking of the tabs, and other phenomena, and the embossing strength retention rate is high.

[0060] The circular protrusions on the surface of the embossing roller are processed by laser engraving, and the laser engraving machine has high control accuracy, high image precision, accurate processing technology, and is made of steel; the soft roller is made of rubber.

[0061] The above is only the preferred embodiment of the utility model, and does not limit the implementation and protection scope of the utility model. For those skilled in the art, it should be realized that any equivalent replacement and obvious change made according to the content of the specification and drawings should be included in the protection scope of the utility model.

Claims

1. A cylindrical core with tabs on the same side, characterized by, The same side end surface of the cylindrical core is provided with a positive electrode tab area and a negative electrode tab area, and the negative electrode tab in the negative electrode tab area has a convex point, and the top of the convex point is flush with the top of the positive electrode tab provided in the positive electrode tab area.

2. The cylindrical core according to claim 1, characterized in that The cross-sectional center of the cylindrical core has a center hole, and the positive electrode tab area and the negative electrode tab area are symmetrically distributed about the center hole.

3. The cylindrical core according to claim 1, characterized in that The positive electrode tab area and the negative electrode tab area further include a low tab area.

4. The cylindrical core according to claim 1, characterized in that The height of the convex point is 2-50 microns.

5. The cylindrical core according to claim 1, characterized in that, The convex point is a circular convex point.

6. A core preparation apparatus, characterized by comprising: The embossing piece, the laser cutting piece, the winding piece and the flattening piece are sequentially arranged along the conveying direction of the to-be-embossed tab sheet. The embossing piece is used for embossing the tab area of the to-be-embossed tab sheet to form a convex point to obtain an embossed tab sheet. The laser cutting piece is used for laser cutting the tab area of the embossed tab sheet to obtain a negative electrode tab sheet. The winding piece is used for winding the negative electrode tab sheet and the positive electrode tab sheet into a core, and the flattening piece flattens the negative electrode tab and the positive electrode tab of the core to obtain the cylindrical core of any one of claims 1-5.

7. The core preparation apparatus according to claim 6, characterized by The embossing piece comprises: A soft roller on which the to-be-embossed tab sheet is wound; An embossing roller provided on one side of the soft roller and corresponding to the tab area of the to-be-embossed tab sheet; An air cylinder for pushing the embossing roller towards the soft roller.

8. The core preparation apparatus according to claim 7, characterized by The depth of the pattern on the embossing roller is 2-50 microns.

9. The core preparation apparatus according to claim 7, characterized by The shape of the convex pattern on the embossing roller is circular.

10. A battery, characterized by The cylindrical core as claimed in any one of claims 1-5.

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