Battery roll core, battery and manufacturing method of battery roll core

Abstract

The invention provides a battery roll core, a battery and a manufacturing method of the battery roll core. A specific embodiment of the method comprises the following steps: alternately laminating diaphragms and pole pieces which are wound into a columnar roll core; a plurality of tab notches are formed in the pole piece side edge of the end surface of the columnar roll core formed by winding the pole piece; the tab notches are laminated on the end surface of the columnar roll core to form a diaphragm exposure area; a part of the side edge of the diaphragm on the same side as the side edge of the pole piece is exposed in the diaphragm exposure area, and under the condition that the columnar roll core is soaked in electrolyte, the part of the exposed side edge of the diaphragm is in full contact with the electrolyte in the diaphragm exposure area. The battery roll core can be in full contact with an electrolyte when the electrolyte is added.

Description

Technical Field

[0001] The embodiments of this application relate to the technical field of batteries, and more particularly to a battery core, a battery, and a method for manufacturing the battery core. Background Technology

[0002] In the structure of the relevant battery core, after the electrode and the separator are wound together, the tabs of the electrode are located on the end face of the cylindrical core and need to be folded down to cover the end face. Therefore, the tabs of the electrode often cover the separator, so that very little part of the separator is exposed.

[0003] Since the separator is almost completely covered by the tabs, it also has the function of absorbing and guiding the diffusion of electrolyte when injecting electrolyte into the battery core. This makes electrolyte injection difficult, as the electrolyte penetration path is blocked by the tabs. The injection process often requires a higher vacuum, a longer holding time, or even high-pressure injection, secondary injection, and heating assistance, which increases the complexity of the process and the manufacturing cost.

[0004] Furthermore, if a cell experiences localized liquid shortage during manufacturing or recycling, the separator is covered by the tabs, making it impossible to replenish the liquid quickly, which leads to a decrease in battery performance consistency and a reduction in battery life.

[0005] Meanwhile, the gas generated during the charging and discharging of the battery cell is difficult to escape smoothly from the end because the separator is covered by the tabs. It tends to accumulate locally inside the battery core, causing safety hazards such as lithium plating. Summary of the Invention

[0006] In view of this, embodiments of the present disclosure provide a method for manufacturing a battery core, a battery, and a battery core.

[0007] In a first aspect, embodiments of this disclosure provide a battery winding core, the battery winding core comprising:

[0008] Diaphragms and electrodes are alternately layered and wound into a cylindrical core;

[0009] Multiple tab notches are provided on the side of the electrode sheet, which is formed by winding the electrode sheet into a columnar core.

[0010] Each tab notch is stacked on the end face of the columnar core to form a diaphragm exposure area;

[0011] The diaphragm exposure area exposes a portion of the diaphragm side on the same side as the electrode side. When the columnar core is immersed in the electrolyte, the exposed portion of the diaphragm side comes into contact with the electrolyte in the diaphragm exposure area.

[0012] In some alternative embodiments, the diaphragm includes a first diaphragm and a second diaphragm;

[0013] The electrode includes a first electrode and a second electrode;

[0014] The first diaphragm, the first electrode, the second diaphragm, and the second electrode are alternately stacked and wound into a cylindrical core.

[0015] In some alternative implementations, the end face of the cylindrical core includes a first end face and a second end face;

[0016] The first electrode sheet is formed by winding one side of the electrode sheet to form the first end face;

[0017] The second electrode is formed by winding the other side of the electrode to form the second end face.

[0018] In some alternative implementations, the multiple tab notches include multiple first tab notches and multiple second tab notches;

[0019] On the first electrode, a first electrode tab with a preset width is provided along the side of the electrode on the first end face; on the second electrode, a second electrode tab with a preset width is provided along the side of the electrode on the second end face.

[0020] The first electrode ear has multiple first electrode ear notches, and the second electrode ear has multiple second electrode ear notches.

[0021] In some alternative embodiments, the portion of the first electrode sheet other than the first tab is a first coating area coated with active material;

[0022] The portion of the second electrode plate, excluding the second electrode tab, is a second coating area coated with active material.

[0023] In some alternative embodiments, neither the first tab notch nor the second tab notch is connected to the first coating area or the second coating area;

[0024] The distance between the edge of the first tab notch and the farthest point from the first end face is greater than or equal to the distance between the diaphragm side edge on the same side of the diaphragm and the first end face.

[0025] The distance between the edge of the second tab notch and the farthest point from the second end face is greater than or equal to the distance between the diaphragm side edge on the same side of the diaphragm and the second end face.

[0026] In some alternative embodiments, the diaphragm exposure area includes a first diaphragm exposure area and a second diaphragm exposure area;

[0027] Each of the first electrode notches is stacked on the first end face to form the first diaphragm exposure area;

[0028] The notches of each second electrode tab are stacked on the second end face to form the second diaphragm exposure area.

[0029] In some optional embodiments, the diaphragm side includes the first diaphragm side of the first diaphragm and the first diaphragm side of the second diaphragm on the same side as the first tab, and the second diaphragm side of the first diaphragm and the second diaphragm side of the second diaphragm on the same side as the second tab.

[0030] The first diaphragm exposure area exposes a portion of the first diaphragm side of the first diaphragm and a portion of the first diaphragm side of the second diaphragm;

[0031] The second diaphragm exposure area exposes a portion of the second diaphragm side of the first diaphragm and a portion of the second diaphragm side of the second diaphragm.

[0032] Secondly, embodiments of this disclosure provide a battery, comprising:

[0033] The battery core and current collector as described in the preceding item, the current collector including a first current collector and / or a second current collector;

[0034] The first end face of the battery core is welded to the first current collector.

[0035] The second end face of the battery core is welded to the second current collector.

[0036] In some alternative implementations, the first collector plate has an opening in the region corresponding to the first diaphragm exposure area in the first end face that matches the first diaphragm exposure area.

[0037] Thirdly, embodiments of this disclosure provide a method for manufacturing a battery core, for manufacturing a battery core as described in any of the preceding embodiments, the method comprising:

[0038] Multiple tab notches are provided on the side of the electrode sheet used to wind and form the end face of the columnar core;

[0039] The diaphragm and electrode sheets are alternately stacked and wound into a cylindrical core;

[0040] The notches of each electrode are stacked on the end face of the columnar core to form the diaphragm exposure area;

[0041] A portion of the diaphragm side, which is on the same side as the electrode side, is exposed through the diaphragm exposure area. When the columnar core is immersed in the electrolyte, the exposed portion of the diaphragm side comes into contact with the electrolyte in the diaphragm exposure area.

[0042] To address the problems of difficult electrolyte injection, insufficient wetting, and poor venting, the battery core, battery, and battery core manufacturing method provided in the embodiments of this disclosure, based on the aforementioned battery core structure, create multiple tab notches on the side of the electrode sheet. This allows for the formation of a separator exposure area after the electrode sheet and separator are wound together, directly exposing a portion of the separator side. Consequently, during electrolyte injection, the contact area and wetting efficiency between the electrolyte and the separator are significantly increased, effectively improving the uniformity of electrolyte distribution within the battery core, shortening the wetting time, and enhancing injection performance and overall manufacturing efficiency.

[0043] In addition, the formation of the separator exposure area not only helps the electrolyte to penetrate and spread quickly and evenly, but also provides an effective exhaust channel for the gas generated during the charging and discharging process of the battery, which helps to prevent the gas from accumulating inside the battery core and improves the battery's cycle performance and safety reliability. Attached Figure Description

[0044] Other features, objects, and advantages of this disclosure will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings. The drawings are for illustrative purposes only and are not intended to limit the invention. In the drawings:

[0045] Figure 1 A structural diagram of one embodiment of a battery winding core;

[0046] Figure 2 This is a structural diagram of another embodiment of the battery winding core disclosed herein;

[0047] Figure 3 This is a structural diagram of one embodiment of the first electrode sheet of this disclosure when unfolded;

[0048] Figure 4A This is a structural diagram of an embodiment of the vertical tab on the end face of the battery core disclosed herein;

[0049] Figure 4B A structural diagram of one embodiment of the battery core end face flattening or kneading the tabs of this disclosure;

[0050] Figure 4C This is a structural diagram of an embodiment of the battery core end face with stacked tabs disclosed herein;

[0051] Figure 5 Structural diagrams of embodiments with different geometric shapes of the end face of the disclosed columnar core;

[0052] Figure 6 Structural diagrams of embodiments with different geometric shapes of the tab notch in this disclosure;

[0053] Figure 7This is a structural diagram of one embodiment of the collector disk of this disclosure;

[0054] Figure 8 This is a structural diagram of another embodiment of the collector disk of this disclosure;

[0055] Figure 9 This is a structural diagram of yet another embodiment of the collector disk of this disclosure;

[0056] Figure 10 A perspective view of one embodiment of the battery disclosed herein;

[0057] Figure 11 This is a cross-sectional view of one embodiment of the battery disclosed herein;

[0058] Figure 12 This is a cross-sectional view of another embodiment of the battery disclosed herein;

[0059] Figure 13 This is a cross-sectional view of yet another embodiment of the battery disclosed herein;

[0060] Figure 14 This is a flowchart of the method for manufacturing the battery core disclosed herein.

[0061] The reference numerals in the above figures are as follows:

[0062] 100. Battery core; 101. Separator; 102. Electrode;

[0063] 103. End face of columnar core; 104. Side of electrode sheet; 105. Notch of electrode tab;

[0064] 106. Diaphragm exposed area; 200. Battery core; 201. First electrode;

[0065] 2011, First electrode tab; 2012, First coating area; 2013, First electrode tab notch;

[0066] 203, First diaphragm; 205, First end face; 2051, First diaphragm exposed area;

[0067] 202, Second electrode plate; 2021, Second electrode tab; 2022, Second coating area;

[0068] 204. Second diaphragm; 206. Second end face; 2014. Width of the first tab;

[0069] 2015, Width of the first coating area; 2016, Width of the first electrode; 2031, Side of the first diaphragm;

[0070] 207. Electrode; 501. Diaphragm exposure area; 502. Diaphragm exposure area;

[0071] 503. Diaphragm exposed area; 504. Diaphragm exposed area; 505. Diaphragm exposed area;

[0072] 506. Diaphragm exposed area; 507. Diaphragm exposed area; 508. Diaphragm exposed area;

[0073] 509. Diaphragm exposed area; 510. Diaphragm exposed area; 511. Diaphragm exposed area;

[0074] 512. Diaphragm exposure area; 601. Tab notch; 602. Tab notch;

[0075] 603. Notch on the tab; 604. Notch on the tab; 606. Notch on the tab;

[0076] 606. Notch on the tab; 607. Notch on the tab; 608. Notch on the tab;

[0077] 609. Notch on the tab; 610. Notch on the tab; 611. Notch on the tab;

[0078] 612. Notch in the tab; 701. First diaphragm exposure area; 702. Second diaphragm exposure area;

[0079] 703, First current collector; 704, Second current collector; 705, Battery core;

[0080] 7041, Second manifold opening; 706, Central channel; 801, First diaphragm exposure area;

[0081] 802. Second diaphragm exposure area; 803. First manifold; 804. Second manifold;

[0082] 8041, Second collector plate opening; 8032, First embossing boss; 8042, Second embossing boss;

[0083] 805. Central channel; 901. First diaphragm exposure area; 902. Second diaphragm exposure area;

[0084] 903, First collector disk; 904, Second collector disk; 9041, Opening of the second collector disk;

[0085] 905. Central channel; 1001. Top cover; 1002. Shell;

[0086] 1003. Bottom cover. Detailed Implementation

[0087] The present disclosure will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, only the parts relevant to the invention are shown in the accompanying drawings.

[0088] It should be noted that, unless otherwise defined, the technical or scientific terms used in the embodiments of this application should have the ordinary meaning understood by one of ordinary skill in the art to which this application pertains. The terms "first," "second," and similar terms used in the embodiments of this application do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are only used to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0089] As described in the background section, the relevant battery cores are still insufficient to meet the needs of actual battery manufacturing.

[0090] In the process of developing this application, the applicant discovered that the main problem with the relevant battery core is that in the existing battery core structure, after the electrode and separator are wound together, the electrode tabs are located on the end face of the cylindrical core and need to be bent over to cover the end face. Therefore, the electrode tabs often cover the separator, resulting in very little of the separator being exposed.

[0091] Because the separator is difficult to almost completely cover the tabs, it also has the function of absorbing and guiding the diffusion of electrolyte when injecting electrolyte into the battery core. This makes electrolyte injection difficult, as the electrolyte penetration path is blocked by the tabs. The injection process often requires higher vacuum, longer holding time, and even high-pressure injection, secondary injection, and heating assistance, which increases the complexity of the process and manufacturing cost.

[0092] Furthermore, if a cell experiences localized liquid shortage during manufacturing or recycling, the separator is covered by the tabs, making it impossible to replenish the liquid quickly, which leads to a decrease in battery performance consistency and a reduction in battery life.

[0093] Meanwhile, the gas generated during the charging and discharging of the battery cell is difficult to escape smoothly from the end because the separator is covered by the tabs. It tends to accumulate locally inside the battery core, causing safety hazards such as lithium plating.

[0094] According to the shape of the tabs, the tabs of the battery core can include, but are not limited to: vertically welded full tabs, flattened full tabs, flattened full tabs, and folded full tabs.

[0095] For vertically welded full tabs, most of the metal foil on the end face remains upright, and only the part welded to the current collector structure is pressed down and welded. Since the effective exposure of the diaphragm at the end is still insufficient, the above-mentioned problems still exist.

[0096] For flattened full-tab, after winding, the metal foil at the end of the electrode is flattened to make the end face a continuous metal plane before contacting the current collector. Its disadvantage is that the end of the core is almost completely covered by metal, and the diaphragm cannot be effectively exposed. Problems such as difficulty in liquid injection, insufficient wetting, and poor air venting still exist.

[0097] For flattened full-tie tabs, similar to flattened tabs, the end metal foil is processed by pressing. Although the process path is different, the end structure and problem manifestations are almost the same as those of flattened tabs.

[0098] For folded full tabs, several folded sheets are cut into the empty foil area of ​​the electrode sheet. During the winding process, the folded sheets fall towards the center of the core and are stacked on top of each other. After being flattened, they are welded to the current collector to establish multi-point contact. However, the end of the battery core in this method is still mainly covered by metal foil, which also has the problems of insufficient separator exposure, poor liquid injection and venting. Even if the folded sheets are locally stacked in the core hole or end, local foil cutting is usually performed. However, the purpose is to eliminate defects or equalize the thickness, but it still cannot improve the above-mentioned problems of insufficient separator exposure, poor liquid injection and venting.

[0099] Based on this, one or more embodiments of this application provide a battery core, a battery, and a method for manufacturing a battery core, based on designing a tab opening structure on the tab, thereby forming a separator exposure area on the end face of the battery core that can expose the separator, thereby allowing the separator to be fully exposed and fully wetted with electrolyte.

[0100] This disclosure will now be described in detail with reference to the accompanying drawings and embodiments.

[0101] It should be noted that, unless otherwise specified, the embodiments and features described in this disclosure can be combined with each other.

[0102] refer to Figure 1 The diagram illustrates a structural representation of an embodiment of the battery core disclosed herein. The battery core 100 includes: a separator 101 and an electrode 102 alternately layered and wound into a cylindrical core. Wherein:

[0103] Multiple tab notches 105 are provided on the side 104 of the electrode sheet 102, which is formed by winding into a columnar core end face 103.

[0104] Each tab notch 105 is stacked on the end face 103 of the columnar core to form a diaphragm exposure area 106.

[0105] The diaphragm exposure area 106 exposes a portion of the diaphragm 101 side on the same side as the electrode side 104. When the columnar core is immersed in the electrolyte, the exposed portion of the diaphragm 101 side comes into contact with the electrolyte in the diaphragm exposure area 106.

[0106] like Figure 1 As shown, the separator 101 can be a porous film that can serve as electronic insulation. When the battery core 100 is wetted by electrolyte, the separator 101 provides a channel for venting gas while providing liquid absorption and wetting functions.

[0107] The electrode 102 can be made of metal foil, such as aluminum foil or copper foil.

[0108] The alternatingly stacked diaphragm 101 and electrode 102 are wound together to form a cylindrical core, i.e. Figure 1 The battery core 100 shown.

[0109] The battery core 100 formed by winding the electrode 102 and the separator 101 is cylindrical. Because the relative positions of the two sides of the electrode 102 and the separator 101 are not aligned during winding, but rather the electrode side 104 of the electrode 102 protrudes beyond the separator side of the separator 101, the cylindrical battery core 100 formed by winding is vertically positioned... Figure 1 In this case, along Figure 1 In the vertical axial positive direction, electrode 102 is in Figure 1 The upper electrode side 104 is higher than the same-side diaphragm 101 side of the diaphragm 101, or the electrode 102 is... Figure 1 The lower electrode side 104 is lower than the same side of the separator 101. Therefore, for the battery core 100 formed by winding, the electrode side 104 of the electrode 102 forms the upper and lower columnar core end faces 103 of the battery core 100 after winding.

[0110] like Figure 1 As shown, the columnar core can be, for example, a cylindrical shape with a circular or elliptical end face 103, or a prismatic shape with a triangular, rectangular, or irregular polygonal end face 103.

[0111] For each electrode 102, there are two parallel and opposite electrode sides 104. Multiple notches are cut at the electrode side 104 where the core is wound to form a columnar core end face 103. Each notch serves as an electrode tab notch 105.

[0112] Since each electrode sheet 102 has multiple tab notches 105 on the side of the columnar core end face 103, after the electrode sheet 102 is wound, the space of the multiple tab notches 105 at the columnar core end face 103 formed by the side 104 of the electrode sheet can be along... Figure 1The radial stacking shown forms a complete region, which is the diaphragm exposure area 106.

[0113] like Figure 1 As shown, when the electrode side 104 protrudes from the diaphragm side 101, by cutting out the tab notch 105 at the end face 103 of the columnar core, the diaphragm side 101 at the diaphragm exposure area 106 of the end face 103 of the columnar core protrudes from the electrode side 104, while the non-diaphragm exposure area 106 where the tab notch 105 is not cut out still has the electrode side 104 protruding from the diaphragm side 101.

[0114] This exposes the side of the diaphragm 101 at the corresponding position in the diaphragm exposure area 106. When the cylindrical core is immersed in the electrolyte, the side of the diaphragm 101 exposed in the diaphragm exposure area 106 can directly contact the electrolyte, compared to the side of the diaphragm 101 not in the diaphragm exposure area 106.

[0115] Based on the structure of the battery core 100 described above, by providing multiple tab notches 105 on the side 104 of the electrode sheet, a separator exposure area 106 can be formed after the electrode sheet 102 and the separator 101 are wound together. This allows a portion of the side of the separator 101 to be directly exposed, thereby significantly increasing the direct contact area and wetting efficiency between the electrolyte and the separator 101 when electrolyte is injected. This effectively improves the uniformity of electrolyte distribution inside the battery core 100, shortens the wetting time, and enhances the electrolyte injection performance and overall manufacturing efficiency.

[0116] In addition, the formation of the separator exposure area 106 not only helps the electrolyte to penetrate and diffuse rapidly and evenly, but also provides an effective exhaust channel for the gas generated during the charging and discharging process of the battery, which helps to prevent the gas from accumulating inside the battery core 100 and improves the battery's cycle performance and safety reliability.

[0117] It should be noted that the above effects are not limited to lithium-ion systems, but are also applicable to sodium-ion, potassium-ion, or other secondary batteries that use separators and liquid electrolytes. Furthermore, there are no restrictions on the diameter of the battery core, including but not limited to battery cores with diameters of Φ18, Φ21, Φ32, and Φ46, all of which can achieve the above effects.

[0118] In some alternative implementations, refer to Figure 2 This shows a structural diagram of another embodiment of the battery core 200 of this disclosure.

[0119] The diaphragm includes a first diaphragm 203 and a second diaphragm 204.

[0120] The electrode includes a first electrode 201 and a second electrode 202.

[0121] The first diaphragm 203, the first electrode 201, the second diaphragm 204, and the second electrode 202 are alternately stacked and wound into a columnar core.

[0122] like Figure 2 As shown, the separator of the battery core 200 includes a first separator 203 and a second separator 204, and the electrode includes a first electrode 201 and a second electrode 202.

[0123] Accordingly, the diaphragm and the electrode can be alternately stacked in the order of first diaphragm 203, first electrode 201, second diaphragm 204 and second electrode 202.

[0124] Among them, the first electrode 201 along Figure 2 The first diaphragm 203 and the second diaphragm 204 protrude in the positive axial direction shown in Figure 2, while the second electrode 202 protrudes in the negative axial direction shown in Figure 2.

[0125] Based on the alternating layering arrangement described above, the first diaphragm 203, the first electrode 201, the second diaphragm 204, and the second electrode 202 are wound together to form a cylindrical core, i.e. Figure 2 The battery core 200 shown.

[0126] Based on the alternating layering arrangement described above, in this columnar core, the outermost layer is the first diaphragm 203, the next layer adjacent to the first diaphragm 203 is the first electrode 201, the next layer adjacent to the first electrode 201 is the second diaphragm 204, and the next layer adjacent to the second diaphragm 204 is the second electrode 202.

[0127] by Figure 2 Taking a cylindrical core formed by winding as an example, the cylindrical core has a first end face 205 and a second end face 206.

[0128] Among them, due to the first electrode 201 along Figure 2 As shown in Figure 2, the first end face 205 is formed by winding the first electrode 201 around one side of the first electrode 201 that protrudes from the first electrode 203 and the second electrode 204, i.e., formed by the electrode side of the first electrode 201 in the positive axial direction. Since the second electrode 202 protrudes from the first electrode 203 and the second electrode 204 in the negative axial direction shown in Figure 2, the second end face 206 is formed by the second electrode 202 protruding from the other side of the first electrode 203 and the second electrode 204, i.e., formed by the electrode side of the second electrode 202 in the negative axial direction.

[0129] In other words, the first end face 205 is a columnar core. Figure 2When placed vertically, the upper columnar core end face, and the second end face 206 are columnar cores. Figure 2 When placed vertically, the lower cylindrical core end face.

[0130] In some embodiments, each electrode may be provided with a tab, with a first tab 2011 provided on the first electrode 201 and a second tab 2021 provided on the second electrode 202.

[0131] Among them, such as Figure 2 As shown, the first tab 2011 is disposed in a strip-shaped area on the side of the first electrode 201 where the first electrode 201 forms the first end face 205, and its length is the length of the side of the electrode, and its width is a preset width. The second tab 2021 is disposed in a strip-shaped area on the side of the second electrode 202 where the second electrode 202 forms the second end face 206, and its length is the length of the side of the electrode, and its width is a preset width.

[0132] Therefore, the multiple electrode notches may include multiple first electrode notches 2013 provided on the first electrode 2011, and multiple second electrode notches provided on the second electrode 2021.

[0133] Furthermore, a coating area is provided on the electrode sheet. This coating area is the region other than the tabs on the electrode sheet, and it is used for coating active materials, such as... Figure 2 As shown, a first coating area 2012 is provided on the first electrode 201, and a second coating area 2022 is provided on the second electrode 202, and active materials are coated on the first coating area 2012 and the second coating area 2022 respectively.

[0134] Among them, the side of the first coating area 2012 and the side of the second coating area 2022, which are on the same side as the same electrode, have different height positions in the axial direction. In the axial upward direction, the side of the first coating area 2012 is higher than the side of the second coating area 2022, and in the axial downward direction, the side of the first coating area 2012 is lower than the side of the second coating area 2022, so that the first coating area 2012 can completely cover the second coating area 2022.

[0135] Furthermore, each diaphragm has a first diaphragm side 2031 and a second diaphragm side, wherein the first diaphragm side 2031 of each diaphragm is the diaphragm side on the same side as the first tab 2011, and the second diaphragm side is the diaphragm side on the same side as the second tab 2021. Therefore, in Figure 2In the axial positive direction shown, the boundary position between the first tab 2011 and the first coating area 2012 is lower than the first diaphragm side 2031 of the first diaphragm 203 and the first diaphragm side 2031 of the second diaphragm 204, and the boundary position between the second tab 2021 and the second coating area 2022 is higher than the second diaphragm side of the first diaphragm 203 and the second diaphragm side of the second diaphragm 204. That is, the two diaphragm sides of each diaphragm are within the width range of the tabs on the same side in the axial direction.

[0136] Specifically, Figure 3 A structural diagram of one embodiment of the first electrode 201 of this disclosure is shown when it is unfolded.

[0137] Combination Figure 2 and 3 As shown, Figure 2 and Figure 3 The width 2014 of the first electrode tab and the width 2015 of the first coating area in the axial direction constitute the width 2016 of the first electrode sheet. Figure 2 and Figure 3 The lengths of the first tab 2011 and the first coating area 2012 in the vertical direction of the axial direction shown are both the electrode side lengths of the first electrode 201.

[0138] Since the first diaphragm 203 and the first electrode 201 need to be stacked, the length of the first diaphragm side 2031 in the direction of the first electrode side, that is, the direction perpendicular to the axial direction, is the same as the length of the first electrode side.

[0139] Therefore, Figure 3 The first electrode notch 2013 provided along the length of the first electrode 2011 shown has its edge at the lowest position in the positive axial direction higher than the side edge on the same side as the first coating area 2012.

[0140] In other words, the height difference D2 between the lowest position of the notch edge of the first tab notch 2013 in the positive axial direction and the side edge on the same side of the first coating area 2012 is greater than 0.

[0141] Furthermore, in the axial direction, the notch edge of the first tab notch 2013 is lower than or equal to the first diaphragm side 2031 on the same side of the first diaphragm 203 and the first diaphragm side 2031 on the same side of the second diaphragm 204 at its lowest position in the positive axial direction.

[0142] In terms of relative position, the farthest position of the notch edge of the first tab notch 2013 from the first end face 205 is greater than or equal to the distance between the first diaphragm side 2031 on the same side and the first end face 205. That is, the difference D1 between the lowest position of the notch edge of the first tab notch 2013 in the positive axial direction and the height of the first diaphragm side 2031 on the same side is greater than or equal to 0.

[0143] It should be noted that, Figure 3 Only a portion of the length and the full axial width of the first electrode 201 are shown; therefore, Figure 3 Only one of the multiple first electrode notches 2013 on the first electrode 2011 is shown.

[0144] Similarly, each second tab notch provided along the length of the second tab 2021 has its notch edge positioned at its highest point in the positive axial direction lower than the side edge on the same side as the second coating area 2022.

[0145] In other words, the height difference D3 between the highest position of the notch edge of the second electrode notch in the positive axial direction and the side edge on the same side of the second coating area 2022 is greater than 0.

[0146] Furthermore, in the axial direction, the highest position of the notch edge of the second electrode notch in the positive axial direction is higher than or equal to the second diaphragm side of the first diaphragm 203 on the same side and the second diaphragm side of the second diaphragm 204 on the same side.

[0147] In terms of relative position, the furthest position of the notch edge of the second electrode notch from the second end face 206 is greater than or equal to the distance between the side of the second diaphragm on the same side and the second end face 206. That is, the difference D4 between the highest position of the notch edge of the second electrode notch in the positive axial direction and the height of the side of the second diaphragm on the same side is greater than or equal to 0.

[0148] Based on this, the notches of each tab can be kept away from the coating area, thereby avoiding damage to the coating area during the processing of the tab notches, which could lead to defective products with safety hazards.

[0149] It should be noted that for the notches cut on each tab, the sum of the side lengths of all the notches is less than or equal to 90% of the total side length of the tabs. This ensures that a certain area of ​​the diaphragm exposure area is formed after the electrode and diaphragm are wound. This ensures that the diaphragm can be directly exposed while also ensuring that the area of ​​the non-diaphragm exposure area, i.e., the tab part, is not too small. In other words, it will not form an excessively narrow welding area like that of multi-tab, thus ensuring the effectiveness of the subsequent welding process.

[0150] In some alternative embodiments, a cylindrical core, namely a battery core 200, is formed by winding the first separator 203, the first electrode 201, the second separator 204, and the second electrode 202, and the first end face 205 and the second end face 206 can form the structure shown in FIG4.

[0151] Specifically, further reference Figure 4A , Figure 4B and Figure 4C It shows a structural diagram of embodiments of the battery core 200 with different tab end faces of the present disclosure.

[0152] in, Figure 4A The structure of the battery core end face formed by the vertical tab structure is shown, such as Figure 4A As shown, the vertical tab structure means that the tab 207 extends in the plane where the corresponding electrode is located, that is, the tabs 207 are all vertical without bending, forming a vertical tab structure.

[0153] in, Figure 4B The structure of the battery core end face formed by flattening or kneading the tab structure is shown, such as... Figure 4B As shown, the flattening or kneading of the tab structure refers to flattening or kneading the tab 207 so that the tab 207 in the non-exposed area of ​​the battery core end face becomes a continuous and flat metal plane.

[0154] in, Figure 4C The structure of the battery core end face formed by the folded tab structure is shown, as follows: Figure 4C As shown, the folded tab structure refers to cutting the tab 207 into several folded pieces. During the winding process, the folded pieces are flattened and laid flat in the radial direction towards the center of the core, so that the tab 207 in the non-exposed area of ​​the battery core end face becomes a continuous metal plane.

[0155] in, Figure 4A , Figure 4B and Figure 4C It can be either the first end face 205 or the second end face 206 of the cylindrical core.

[0156] like Figure 4A , Figure 4B and Figure 4C As shown, based on Figure 1 After an electrode sheet with multiple tab notches is wound, it forms a columnar core end face as shown in Figure 4. In this columnar core end face, since one of the two electrode sheet sides on the same side protrudes from the diaphragm side on the same side, and since the diaphragm side of each diaphragm is within the axial width range of the tab 207 on the same side, the electrode sheet side that forms the columnar core end face is the tab side of this electrode sheet.

[0157] Since each tab 207 has multiple tab notches, the shape and spacing of the multiple tab notches can be adjusted so that after the tab 207 of the electrode sheet is wound, each tab notch can be stacked radially at the end face of the columnar core. At the stacked tab notches, a diaphragm exposure area as shown in Figure 4 is formed, thereby exposing a portion of the diaphragm side on the same side as the tab 207 to the diaphragm exposure area.

[0158] Furthermore, for the first end face 205 of the cylindrical core, since the first end face 205 is formed by the first tab 2011, the diaphragm exposure area formed by the first tab notch 2013 is designated as the first diaphragm exposure area 2051. For the second end face 206 of the cylindrical core, since the second end face 206 is formed by the second tab 2021, the diaphragm exposure area formed by the second tab notch is designated as the second diaphragm exposure area.

[0159] Accordingly, the diaphragm side exposed in the first diaphragm exposure area 2051 is the first diaphragm side 2031 of the first diaphragm 203 and the first diaphragm side 2031 of the second diaphragm 204, while the diaphragm side exposed in the second diaphragm exposure area is the second diaphragm side of the first diaphragm 203 and the second diaphragm side of the second diaphragm 204.

[0160] pass Figure 4A , Figure 4B and Figure 4C It can be seen that regardless of the shape of the tab 207 forming the end face, an effective diaphragm exposure area 106 can be formed. Therefore, the structure of the diaphragm exposure area can be applied to the above-mentioned vertical tab structure, flattened tab structure, kneaded tab structure and folded tab structure.

[0161] In some alternative implementations, the exposed areas of the wound diaphragm can be one or more.

[0162] Specifically, further reference Figure 5 It shows a structural diagram of embodiments with different geometric shapes of the end face of the columnar core of this disclosure.

[0163] like Figure 5 As shown, the exposed area of ​​the wound diaphragm can exhibit various geometric shapes on the end face of the columnar core. The exposed area of ​​the diaphragm can be: a single fan-shaped area facing the center of the core, for example... Figure 5 A single diaphragm exposure area 501; or multiple fan-shaped areas facing the center of the core, for example Figure 5 Two diaphragm exposure areas 506, three diaphragm exposure areas 507, and four diaphragm exposure areas 508; or a single fan-shaped area facing the center of the core, for example... Figure 5 Diaphragm exposure areas 501 and 502; or one or more rectangular or elongated linear areas, for example Figure 5 The diaphragm exposure area 503 and diaphragm exposure area 505; or one or more strip-shaped areas extending arcuately along the end face, for example Figure 5 The diaphragm exposure area 504; or one or more concentric annular regions centered on the end face center, for example... Figure 5 The diaphragm exposure area 509; or one or more square or circular areas, for example Figure 5 The three diaphragm exposure areas 510 and 511; or irregular blocky or strip-shaped regions formed by process combinations or phase differences, for example Figure 5 The diaphragm exposure area 512; or a combination of the above geometric shapes.

[0164] also, Figure 5 The diaphragm exposure areas 502 to 512 shown can all be based on their current geometry, with a narrow annular diaphragm exposure area cut along the edge of the columnar core end face, so that the diaphragm can be better exposed to the electrolyte; a small circular opening covering the center of the columnar core end face can also be cut at the center of the columnar core end face, which can also allow the diaphragm to be better exposed to the electrolyte.

[0165] exist Figure 5 The columnar core end faces and diaphragm exposure areas with different geometric shapes shown can all be directly exposed to form gas-liquid channels dominated by the diaphragm.

[0166] The multiple tabs of each tab can be set according to the geometric parameters of the columnar core, such as inner diameter, number of layers, thickness of the electrode sheet and thickness of the diaphragm, as well as the winding process parameters, such as tension and start and end phases, to set the phase offset (distance) between the tabs and the size and shape of the tabs. This allows each tab to be stacked and aligned after winding, thus ensuring that after winding, the tabs form a diaphragm exposure area in the radial direction of the end face of the columnar core.

[0167] At the same time, based on the different phase offsets (distances) between the tab notches and the different geometric shapes and sizes of the tab notches, diaphragm exposure areas with different geometric shapes can also be obtained.

[0168] Among them, reference Figure 6 The diagram shows a structural diagram of embodiments of different geometries of the tab notch of this disclosure.

[0169] like Figure 6 As shown, the geometry of the tab notch can be trapezoidal, for example... Figure 6 The tab notches 605 and 608 in the figure; or they can be rectangular, for example. Figure 6The tab notches 601, 602, and 603 are shown in the figure; or they can be parallelograms, for example... Figure 6 The notch in the tab is 606; or it can be semi-circular, for example. Figure 6 The notch in the tab is 604; or it can be semi-elliptical, for example. Figure 6 The notch 609 in the electrode lug; or it could be triangular, for example... Figure 6 The tab notch 607 in the middle; or the tab notch 610 corresponding to the folded tab structure.

[0170] It should be further explained that the tab notch 610 includes not only a parallelogram-shaped notch, but also multiple oblique slits for realizing the folded tab structure.

[0171] In the different geometric shapes of the above-mentioned tab notches, in order to reduce stress concentration that causes the foil of the electrode to tear, the corners of the notch can be designed as rounded corners or chamfers.

[0172] Based on this, in actual production, due to the tolerance between the thickness of the electrode sheet and the thickness of the separator, fluctuations in winding tension, and slight deviations in the cutting phase, the exposed area of ​​the separator on the end face of the cylindrical core may exhibit slight misalignment, distortion, or irregular edges. For example, the expected fan-shaped or rectangular geometric shape of the exposed area may actually appear as an unexpected block or strip-shaped area. However, as long as the exposed area of ​​the separator is not largely closed due to the above errors, and the electrode area outside the exposed area can still be welded normally, the slight misalignment, distortion, or irregular edges caused by the above deviations will not affect the expected functions of providing liquid absorption and wetting, as well as the channel function of venting gas. Therefore, the manufacturing tolerance of the battery core is high, and the expected effect can be stably achieved under actual mass production conditions.

[0173] Based on this, by designing the shape, size and arrangement of the tab notch, a diaphragm exposure area with a specific geometric shape can be formed on the end face of the columnar core after winding. This allows the diaphragm exposure area to directly expose the diaphragm side, thereby forming an effective gas-liquid channel dominated by the diaphragm when the electrolyte is injected, which significantly improves the electrolyte wetting efficiency and gas discharge capacity.

[0174] In some alternative embodiments, the battery includes the aforementioned battery core, i.e., a cylindrical core, and a current collector; the current collector may include a first current collector and a second current collector, which are respectively welded to the two cylindrical core end faces of the battery core.

[0175] The two columnar core end faces can correspond to the two poles of the battery core, for example, the first end face corresponds to the negative pole of the battery core and the second end face corresponds to the positive pole of the battery core. The first end face is welded to the first current collector and the second end face is welded to the second current collector. The geometric shapes of the first current collector and the second current collector can be the same or different.

[0176] Since the two battery core end faces correspond to the positive and negative electrodes respectively, and both are provided with a separator exposure area, for the battery core end face corresponding to the positive electrode, an opening with a matching geometry can be set in the area corresponding to the separator exposure area in its corresponding current collector.

[0177] In some cases, taking the example that both the first end face and the second end face are provided with a fan-shaped membrane exposure area, the first end face corresponds to the negative electrode of the battery. For the first current collector corresponding to the first end face, the same fan-shaped opening can be provided in the area of ​​the first current collector corresponding to the first membrane exposure area, so as to ensure that the first current collector and the second current collector will not cover the membrane, so that the membrane can be fully exposed; while the second current collector is not provided with an opening.

[0178] In other cases, such as when the opening shape of the manifold allows most of the diaphragm exposure area to be fully exposed, it can also be considered that the opening of the manifold matches the geometry of the diaphragm exposure area.

[0179] refer to Figure 7 The diagram shows a structural diagram of one embodiment of the collector disk of this disclosure.

[0180] in, Figure 7 Corresponding Figure 4B The columnar core end face formed by the flattened or patted tab structure, such as Figure 7 As shown, the first separator exposure area 701 of the battery core 705 corresponds to the negative electrode of the battery, and the second separator exposure area 702 corresponds to the positive electrode of the battery. When both the first separator exposure area 701 and the second separator exposure area 702 are fan-shaped, the second current collector opening 7041 of the second current collector 704 is rectangular, but it can still expose most of the second separator exposure area 702. Therefore, even if the geometry of the second current collector opening 7041 is different from that of the second separator exposure area 702, it can still be considered that the second current collector opening 7041 matches the second separator exposure area 702, while the first current collector 703 has no opening.

[0181] refer to Figure 8 This shows a structural diagram of another embodiment of the collector disk of this disclosure.

[0182] in, Figure 8 Corresponding Figure 4A The columnar core end face formed by the vertical tab structure in the middle, such as Figure 8 As shown, the first diaphragm exposure area 801 corresponds to the negative electrode of the battery, and the second diaphragm exposure area 802 corresponds to the positive electrode of the battery. When both the first diaphragm exposure area 801 and the second diaphragm exposure area 802 are fan-shaped, the second current collector opening 8041 of the second current collector 804 is circular, but it can still expose most of the second diaphragm exposure area 802. Therefore, even if the geometry of the second current collector opening 8041 is different from that of the second diaphragm exposure area 802, it can still be considered that the second current collector opening 8041 matches the second diaphragm exposure area 802; while the first current collector 803 has no opening.

[0183] refer to Figure 9 This shows a structural diagram of another embodiment of the collector disk of this disclosure.

[0184] in, Figure 9 Corresponding Figure 4C The columnar core end face formed by the folded tab structure in the middle, such as Figure 9 As shown, the first separator exposure area 901 corresponds to the negative electrode of the battery, and the second separator exposure area 902 corresponds to the positive electrode of the battery. When both the first separator exposure area 901 and the second separator exposure area 902 are fan-shaped, the shape of the second current collector 904 is a circle with the core removed and three other large fan-shaped areas larger than the fan-shaped areas of the second separator exposure area. This exposes not only the entire second separator exposure area 902, but also a portion of the electrode tabs. Therefore, even though the geometry of the second current collector opening 9041 is different from that of the second separator exposure area 902, it can still be considered that the second current collector opening 9041 of the second current collector 903 matches the second separator exposure area 902; while the first current collector 903 has no opening.

[0185] Based on this, by setting an opening on the current collector that matches the geometry of the separator exposure area, it is ensured that the separator exposure area on the end face of the battery core can be fully exposed. This allows the current collector to achieve the function of welding connection with the tabs without obstructing or hindering the gas-liquid channel dominated by the separator. This ensures that there is sufficient welding area between the tabs and the current collector to achieve a reliable welding connection, while maintaining the unobstructed flow of the separator exposure area, so that the electrolyte wetting and gas conduction functions can be effectively performed.

[0186] In some alternative implementations, the battery core is welded to the corresponding current collector.

[0187] Specifically, the tabs on the two end faces of the columnar core are welded to the corresponding collector plates, and the welding positions can be far away from the diaphragm exposure area.

[0188] exist Figure 7In the example, on the side of the second collector plate 703 opposite to the cylindrical end face of the core, a limiting tie or a limiting step structure can be provided at the edge of the opening 7041 of the second collector plate, corresponding to the flattened electrode tab structure or the flattened electrode tab structure on the cylindrical end face of the core.

[0189] Based on this, by setting a limiting tie or limiting step at the edge of the opening 7041 of the second collector plate, the relative position of the second collector plate 704 to the core column end face can be fixed, ensuring that the second collector plate 704 does not shift, thus providing a stable and reliable connection basis for welding.

[0190] exist Figure 8 In the example, on the side of the first collector plate 803 opposite to the cylindrical end face of the core, a plurality of first embossing protrusions 8032 are provided along the radial direction of the first collector plate 803, corresponding to the vertical tab structure on the cylindrical end face of the core. The distance between each first embossing protrusion 8032 can be uniform or non-uniform. On the side of the second collector plate 804 opposite to the cylindrical end face of the core, a plurality of second embossing protrusions 8042 are also provided along the radial direction of the second collector plate 804. The distance between each second embossing protrusion 8042 can be uniform or non-uniform. The number of first embossing protrusions 8032 and second embossing protrusions 8042 can be the same or different.

[0191] The first embossing protrusion 8032 and the second embossing protrusion 8042 are used to press the electrode tabs together and weld them to the electrode tabs.

[0192] Specifically, the first embossing protrusion 8032 and the second embossing protrusion 8042 can deform or collapse the corresponding electrode tab when it is pressed tightly into it, so as to make it closely abut against the electrode tab, thereby allowing the first embossing protrusion 8032 and the second embossing protrusion 8042 to be welded to the corresponding electrode tab.

[0193] When the first embossed protrusion 8032 and the second embossed protrusion 8042 are welded to their corresponding tabs, welding can be achieved by, for example, laser welding, in which a laser is directed from the outward side of the first embossed protrusion 8032 and the second embossed protrusion 8042 into the welding position.

[0194] Based on this, by setting radially distributed embossed protrusions on the manifold and pressing them into the tabs to deform or collapse them, a large-area close contact between the manifold and the tabs is achieved, thus providing a stable and reliable connection basis for welding.

[0195] exist Figure 9 In the example, on the side of the second collector plate 904 opposite to the cylindrical end face of the core, a limiting tie or a limiting step structure can be provided at the edge of the opening 9041 of the second collector plate, corresponding to the folded tab structure on the cylindrical end face of the core.

[0196] Based on this, by setting a limiting tie or limiting step at the edge of the opening 9041 of the second collector plate, the relative position of the second collector plate 904 to the cylindrical end face of the core can be fixed, ensuring that the second collector plate 904 does not shift, thus providing a stable and reliable connection basis for welding.

[0197] In some alternative embodiments, the battery may further include a top cover, a casing, and a bottom cover, based on the battery core with the first and second current collectors welded on.

[0198] refer to Figure 10 The diagram shows a perspective view of one embodiment of the battery disclosed herein.

[0199] like Figure 10 As shown, the top cover 1001 is located at the positive terminal of the battery. When the second current collector corresponds to the positive terminal, the top cover 1001 can be used to cover the second current collector, and the bottom cover 1003 is used to cover the first current collector.

[0200] In some other cases, the top cover 1001, the housing 1002, and the bottom cover 1003 can also be directly installed on a battery core that does not have a first current collector and a second current collector. The top cover 1001 and the bottom cover 1003 can respectively directly cover the second end face and the first end face.

[0201] Figure 10 This corresponds to the above. Figure 7 , Figure 8 and Figure 9 For example, after welding the second current collector and the first current collector to the battery core, the housing 1002 and the bottom cover 1003 can be installed. After the housing 1002 and the bottom cover 1003 seal the battery core with the first current collector and the second current collector, electrolyte can be injected into it.

[0202] The bottom cover 1003 and the shell 1002 can be two separate parts, or they can be two parts of an integral cup-shaped component. If the bottom cover 1003 and the shell 1002 are two parts of an integral cup-shaped component, then the top cover 1001 and this cup-shaped component are two separate parts.

[0203] In other cases, the top cover 1001 and the housing 1002 can be two separate parts, or they can be two parts of an integral cup-shaped component. If the top cover 1001 and the housing 1002 are two parts of an integral cup-shaped component, then the bottom cover 1003 and this cup-shaped component are two separate parts.

[0204] After the electrolyte is injected, the diaphragm can fully contact the electrolyte through the central channel formed by the winding of the electrode and the diaphragm and the exposed area of ​​the diaphragm. This allows the electrolyte to be absorbed and guided to the electrode by the diaphragm, so that the electrode can be fully wetted by the electrolyte.

[0205] Meanwhile, the gas generated inside the battery core can also be discharged through the diaphragm exposure strip.

[0206] refer to Figure 11 The diagram shows a cross-sectional view of one embodiment of the battery disclosed herein.

[0207] Figure 11 The cross-sectional view corresponds to the above. Figure 7 Examples, such as Figure 11 As shown, the first current collector 703 and the second current collector 704 can be tightly attached to the flattened electrode tab structure or the flattened electrode tab structure. The central channel 706 and the separator exposure area formed after the electrode sheet and separator are wound can serve as a complete gas-liquid channel inside the battery core. When electrolyte is injected into the battery core, the electrolyte can reach the bottom of each electrode layer through the central channel 706 and the bottom second separator exposure area 702, and reach the top of each electrode layer through the top first separator exposure area 701. This can greatly optimize the liquid injection and wetting effect. At the same time, the gas generated inside the battery core can be discharged from the first separator exposure area 701, which can prevent the accumulation of gas inside the battery core from affecting the cycle and safety performance.

[0208] refer to Figure 12 The diagram shows a cross-sectional view of another embodiment of the battery disclosed herein.

[0209] Figure 12 The cross-sectional view corresponds to the above. Figure 8 Examples, such as Figure 12 As shown, the first current collector 803 and the second current collector 804 can press their respective protrusions into the vertical electrode structure, thereby making tight contact with the vertical electrode structure. The central channel 805 and the separator exposure area formed after the electrode and separator are wound can serve as complete gas-liquid channels inside the battery core. When electrolyte is injected into the battery core, the electrolyte can reach the bottom of each electrode layer through the central channel 805 and the bottom second separator exposure area 802, and reach the top of each electrode layer through the top first separator exposure area 801. This can greatly optimize the liquid injection and wetting effect. At the same time, the gas generated inside the battery core can be discharged from the first separator exposure area 801, which can prevent the accumulation of gas inside the battery core from affecting the cycle and safety performance.

[0210] refer to Figure 13 The diagram shows a cross-sectional view of yet another embodiment of the battery disclosed herein.

[0211] Figure 13 The cross-sectional view corresponds to the above. Figure 9 Examples, such as Figure 13 As shown, the first current collector 903 and the second current collector 904 can be closely attached to the stacked electrode tab structure. The central channel 905 and the separator exposure area formed after the electrode sheets and separator are wound can serve as complete gas-liquid channels inside the battery core. When electrolyte is injected into the battery core, the electrolyte can reach the bottom of each electrode layer through the central channel 905 and the bottom second separator exposure area 902, and reach the top of each electrode layer through the top first separator exposure area 901. This can greatly optimize the liquid injection and wetting effect. At the same time, the gas generated inside the battery core can be discharged from the first separator exposure area 901, which can prevent the accumulation of gas inside the battery core from affecting the cycle and safety performance.

[0212] Based on this, a complete gas-liquid channel is constructed inside the battery through the synergistic effect of the central channel and the exposed area of ​​the separator. The electrolyte can fully reach the bottom of each electrode layer through the central channel and the bottom exposed area of ​​the separator, while effectively covering the top of each electrode layer through the top exposed area of ​​the separator, thereby achieving rapid and uniform wetting of the electrolyte inside the core.

[0213] At the same time, it provides an effective exhaust path for the gas generated during the charging and discharging process of the battery. The gas can be smoothly discharged from the top diaphragm exposure area, avoiding the accumulation of gas inside the core, thereby helping to improve the cycle life and safety performance of the battery.

[0214] Further reference Figure 14 As a realization process of the battery core shown in the above figures, this disclosure provides an embodiment of a method for manufacturing a battery core, which is similar to... Figure 1 The embodiments of the battery core shown correspond to those for manufacturing the battery cores in any of the preceding embodiments, and the method can be specifically implemented by various electronic devices.

[0215] like Figure 14 As shown, the process 1400 of the battery core manufacturing method in this embodiment includes:

[0216] Embodiments of this disclosure provide a method for manufacturing a battery core, comprising:

[0217] S1401, multiple tab notches are provided on the side of the electrode sheet used to wind the electrode sheet to form the end face of the columnar core.

[0218] S1402, the diaphragm and electrode are alternately stacked and wound into a cylindrical core.

[0219] S1403, the notches of each tab are stacked on the end face of the columnar core to form the diaphragm exposure area.

[0220] S1404, through the diaphragm exposure area, a portion of the diaphragm side on the same side as the electrode side is exposed. When the columnar core is immersed in the electrolyte, the exposed portion of the diaphragm side comes into contact with the electrolyte in the diaphragm exposure area.

[0221] In this embodiment, the specific processing of the battery core manufacturing method and its resulting technical effects can be referred to separately. Figure 1 The relevant descriptions in the corresponding embodiments will not be repeated here.

[0222] The above description is merely a preferred embodiment of this disclosure and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of this disclosure is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the above-described concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features disclosed in this disclosure that have similar functions.

Claims

1. A battery jelly-roll, comprising: a separator and a tab sheet alternately laminated and wound into a cylindrical jelly-roll; a plurality of tab cutouts are provided on a tab sheet side edge of the tab sheet wound to form an end face of the cylindrical jelly-roll; each of the tab cutouts laminates to form a separator exposure area on the end face of the cylindrical jelly-roll; the separator exposure area exposes a partial area of a separator side edge on the same side as the tab sheet side edge, and in the case of immersing the cylindrical jelly-roll in an electrolyte, the partial area of the separator side edge exposed contacts the electrolyte at the separator exposure area.

2. The battery jelly-roll of claim 1, wherein, the separator comprises a first separator and a second separator; the tab sheet comprises a first tab sheet and a second tab sheet; the first separator, the first tab sheet, the second separator and the second tab sheet are alternately laminated and wound into a cylindrical jelly-roll.

3. The battery jelly-roll of claim 2, wherein, the end face of the cylindrical jelly-roll comprises a first end face and a second end face; one side tab sheet side edge of the first tab sheet is wound to form the first end face; the other side tab sheet side edge of the second tab sheet is wound to form the second end face.

4. The battery jelly-roll of claim 3, wherein, the plurality of tab cutouts comprises a plurality of first tab cutouts and a plurality of second tab cutouts; on the first tab sheet, a first tab with a preset width is provided along the tab sheet side edge of the first end face, and on the second tab sheet, a second tab with a preset width is provided along the tab sheet side edge of the second end face; the first tab is provided with a plurality of first tab cutouts, and the second tab is provided with a plurality of second tab cutouts.

5. The battery jelly-roll of claim 4, wherein, a part of the first tab sheet other than the first tab is a first coated area coated with an active material; a part of the second tab sheet other than the second tab is a second coated area coated with an active material.

6. The jelly-roll battery core according to claim 5, wherein the first tab cutout and the second tab cutout are both not connected to the first coated area and the second coated area; a distance between a position farthest from the first end face of a cutout edge of the first tab cutout and the first end face is greater than or equal to a distance between the separator side edge on the same side as the first end face and the first end face; a distance between a position farthest from the second end face of a cutout edge of the second tab cutout and the second end face is greater than or equal to a distance between the separator side edge on the same side as the second end face and the second end face.

7. The jelly-roll battery core of claim 4, wherein, the separator exposure area comprises a first separator exposure area and a second separator exposure area; each of the first tab cutouts laminates to form the first separator exposure area on the first end face; each of the second tab cutouts laminates to form the second separator exposure area on the second end face.

8. The battery jelly-roll of claim 5, wherein, the separator side edge comprises a first separator side edge of the first separator and a first separator side edge of the second separator on the same side as the first tab, and a second separator side edge of the first separator and a second separator side edge of the second separator on the same side as the second tab; the first separator exposure area exposes a partial area of the first separator side edge of the first separator and a partial area of the first separator side edge of the second separator; the second separator exposure area exposes a partial area of the second separator side edge of the first separator and a partial area of the second separator side edge of the second separator.

9. A battery comprising: a current collector and the battery jelly-roll according to any one of claims 1-8, the current collector comprises a first current collector and / or a second current collector. The first end surface of the battery jelly-roll is welded to the first current collector plate. The second end surface of the battery jelly-roll is welded to the second current collector plate.

10. The battery of claim 9, wherein, The first current collector plate is provided with an opening matching the first separator exposed area in a region corresponding to the first separator exposed area in the first end surface.

11. A method for manufacturing a battery jelly-roll, for manufacturing the battery jelly-roll according to any one of claims 1-8, the method comprising: providing a plurality of tab cutouts on the tab side edges of the pole pieces used to wind the pole pieces to form the cylindrical jelly-roll end surface; alternately stacking the separator and the pole pieces to wind the pole pieces into a cylindrical jelly-roll; stacking each tab cutout in the cylindrical jelly-roll end surface to form a separator exposed area; exposing a partial area of the separator side edge on the same side as the tab side edge through the separator exposed area, and in the case of immersing the cylindrical jelly-roll in electrolyte, the partial area of the separator side edge exposed is in contact with the electrolyte at the separator exposed area.

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