Battery electrode plate, battery, and method for manufacturing battery electrode plate

Abstract

The present disclosure provides a battery electrode plate, a battery, and a method for manufacturing the battery electrode plate. The battery electrode plate includes an electrode plate body and a tab, the electrode plate body is provided with a tab mounting groove communicating with a first edge of the electrode plate body and a first groove communicating with a second edge of the electrode plate body, the first edge and the second edge being two opposing edges of the electrode plate body, and the tab is connected in the tab mounting groove. The battery electrode plate of the present disclosure is less likely to break, and the battery has high reliability.

Description

[Technical Field]

[0001] FIELD OF THE DISCLOSURE The present disclosure relates to the field of battery technology, and in particular to battery electrode plates, batteries, and methods of fabricating battery electrode plates. [Background technology]

[0002] With the development of science and technology, lithium ion battery technology has developed rapidly. At the same time, users' requirements for fast charging capability of lithium ion batteries have increased, and fast charging lithium ion batteries have become the development trend of consumer lithium ion batteries.

[0003] To improve the battery's fast charging performance, a tab-intermediate placement structure is commonly used in lithium-ion batteries. Specifically, the tabs are moved to positions such as 3 / 4, 1 / 3, or 1 / 2 of the positive and negative electrode plates to reduce the cell's internal resistance, optimize the current density distribution on the electrode plates during charging and discharging, and improve the battery's fast charging capability. When using the tab-intermediate placement structure, a wide-width cleaning technique is typically used to improve production efficiency and reduce battery safety risks. Specifically, a single electrode plate substrate is first machined with tab welding grooves on both the front and back sides, which are blank current collectors. The electrode plate substrate is then cut along the widthwise edges of the tab welding grooves into multiple battery electrode plates. During this process, due to inconsistencies in the cutting or the precision of the cutting equipment, the cutting often does not follow the widthwise edges of the tab welding grooves. This results in a coating area between the electrode plate edge and the tab welding groove edge. To prevent this from affecting the flatness of the battery electrode plate, a subsequent punching process is performed to remove the coating area.

[0004] In the battery electrode plate formed by the above process, a through groove is formed by punching between the tab welding groove and the edge of the electrode plate, and the side of the through groove closer to the battery edge has a notch structure, and the side closer to the tab welding groove is directly connected to the tab welding groove. The thickness at the location of the tab welding groove is thin, and not only does it have to withstand the thickness of the current collector, but it also has to withstand high-temperature welding when attaching the lug. As a result, stress is concentrated on the side of the through groove closer to the tab welding groove, making the electrode plate prone to rupture and affecting the reliability of the battery. Summary of the Invention [Problem to be solved by the invention]

[0005] In view of the above problems, the embodiments of the present application provide a battery electrode plate, a battery, and a method for manufacturing a battery electrode plate, which makes the battery electrode plate highly reliable and less susceptible to damage. [Means for solving the problem]

[0006] In order to achieve the above object, a first aspect of the present application provides an electrode plate for a battery, comprising an electrode plate body and a tab, the electrode plate body having a tab mounting groove communicating with a first edge of the electrode plate body and a first groove communicating with a second edge of the electrode plate body, the first edge and the second edge being two opposing edges of the electrode plate body, and the tab being connected within the tab mounting groove.

[0007] In one possible embodiment, along a direction from the second edge to the first edge, the projection of the first groove on the first edge covers at least a portion of the projection of the tab attachment groove on the first edge.

[0008] In one possible embodiment, the first groove has a groove opening located at the second edge, and the length of the groove opening of the first groove along a direction parallel to the first edge is greater than the width of the tab; and / or The tab mounting groove has an opening located at the first edge, and the first groove has a slot mouth located at the second edge, and the length of the opening is less than or equal to the length of the slot mouth along a direction parallel to the first edge.

[0009] In one possible embodiment, the electrode plate body includes a current collector and an active material layer provided on at least one surface of the current collector, with the active material layer in the region between the tab attachment groove and the first groove.

[0010] In one possible embodiment, the width of the active material layer between the tab attachment groove and the first groove along the direction from the first edge to the second edge is greater than the sum of the widths of the tab attachment groove and the first groove.

[0011] In one possible embodiment, the tab mounting groove has an opening located at the first edge, the bottom of the tab mounting groove is a current collector, and three peripheral sides of the tab mounting groove are active material layers.

[0012] In one possible embodiment, an active material layer is provided on each of the two surfaces of the current collector, and the active material layer on the surface of the current collector opposite the tab mounting groove is provided with a second tab mounting groove arranged opposite the tab mounting groove, and the length of the second tab mounting groove is greater than the length of the tab mounting groove and / or the width of the second tab mounting groove is greater than the width of the tab mounting groove along the width direction of the electrode plate body.

[0013] In one possible embodiment, the first groove has a groove opening located at the second edge, the bottom of the first groove is the current collector, and the peripheral side of the first groove is the active material layer.

[0014] In one possible embodiment, an active material layer is provided on each of the two surfaces of the current collector, and the active material layer on the surface of the current collector opposite the first groove is provided with a second groove arranged to face the first groove, and the length of the second groove is longer than the length of the first groove along the length direction of the electrode plate body, and / or the width of the second groove is No. Greater than the width of one groove.

[0015] In one possible embodiment, an active material layer is provided on each of the two surfaces of the current collector, a tab attachment groove is provided in the active material layer on one side, the tab is welded to the current collector, and the weld point on the surface of the current collector opposite the tab is covered with the active material layer.

[0016] In one possible embodiment, the first groove is located on the same side of the active material layer as the tab attachment groove, and the other side of the current collector opposite the first groove has an active material layer.

[0017] In one possible embodiment, the tab mounting groove in which the tab is received is covered with a first insulating layer, and / or the first groove is covered with a second insulating layer.

[0018] In one possible embodiment, the tab has a first step located within the tab mounting groove and a second step extending from the tab mounting groove, with a tab adhesive provided on the second step, and the first insulating layer covering a portion of the tab adhesive.

[0019] In one possible embodiment, the second insulating layer extends beyond the second edge by a distance of less than 3 mm.

[0020] In one possible embodiment, a second tab mounting groove is provided on the surface of the battery electrode plate opposite the tab mounting groove, the second tab mounting groove being provided opposite the tab mounting groove, the second tab mounting groove being covered with a fifth insulating layer, and the first insulating layer The part beyond the first edge of and portions beyond the first edge of the fifth insulating layer are bonded to each other.

[0021] In one possible embodiment, the first groove is a through groove that penetrates the electrode plate along the thickness direction of the electrode plate.

[0022] In one possible embodiment, the size of the tab mounting groove along the width direction of the electrode plate body is L1, the size of the first groove along the width direction of the electrode plate body is L2, the sizes of the tab mounting groove and the first groove along the length direction of the electrode plate body are both D, the size of the tab along the length direction of the electrode plate body is W, and the size of the electrode plate substrate along the length direction of the electrode plate body is Z; L1 ≥ L2, L1 = (0.1 ~ 0.6) × Z, L2 is 0.1mm to 15.0mm. The condition D = (1.0~4.0) × W is met.

[0023] In a second aspect of the present application, a battery is provided, comprising a cell formed by stacking a first electrode plate, a separator, and a second electrode plate and then winding the stack, wherein the first electrode plate and the second electrode plate have opposite polarities, and the first electrode plate is an electrode plate for the battery described above.

[0024] In one possible embodiment, the surface of the active material layer of the second electrode plate facing the tab attachment groove is covered with a third insulating layer.

[0025] In one possible embodiment, the surface of the active material layer of the second electrode plate facing the first groove is covered with a fourth insulating layer.

[0026] In a third aspect of the present application, there is provided a method for fabricating an electrode plate for a battery, the method comprising: Providing a plurality of recessed grooves spaced apart in a first direction of the electrode plate substrate on one surface of the electrode plate substrate; cutting the electrode plate substrate into a plurality of electrode plate bodies along a plurality of cutting lines, and dividing each groove into a tab mounting groove and a first groove along the cutting lines, the tab mounting groove and the first groove divided and cut from the same groove being located in different electrode plate bodies; and welding the tab into the tab mounting groove of the electrode plate body to form the battery electrode plate; A plurality of cutting lines are provided on the electrode plate substrate at intervals along the first direction, and the plurality of cutting lines are provided in one-to-one correspondence with the grooves, and each cutting line passes through the corresponding groove.

[0027] In one possible embodiment, After welding the tab into the tab mounting groove of the electrode plate body, The method further includes covering a first insulating layer at the groove opening of the tab mounting groove where the tab is mounted, and covering a second insulating layer at the groove opening of the first groove.

[0028] In one possible embodiment, After cutting to obtain the electrode plate body, The method further includes punching a notch in the electrode plate body at the position where the first groove is formed. [Effects of the Invention]

[0029] According to the battery electrode plate, battery, and method for manufacturing the battery electrode plate of the present application, the battery electrode plate comprises an electrode plate body and a tab, the electrode plate body is provided with a tab mounting groove communicating with a first edge of the electrode plate body and a first groove communicating with a second edge of the electrode plate body, the first edge and the second edge being two opposing edges of the electrode plate body, and the tab is connected to the tab mounting groove. In the above solution, the tab mounting groove communicates with the first edge of the electrode plate body, and the first edge is flat and has no notch, thereby reducing the probability of rupture and improving the safety and reliability of the battery electrode plate.

[0030] The configuration of the present disclosure, as well as other objects and advantageous effects of the disclosure, will become clearer and easier to understand by describing preferred embodiments with reference to the drawings. [Brief explanation of the drawings]

[0031] [Figure 1a] 1 is a schematic diagram of the structure of a battery electrode plate cut when there is a difference in cutting in the prior art. [Figure 1b] 10 is a schematic diagram of the structure of a battery electrode plate cut when there is a difference in cutting operation and no tab is attached to the cut electrode plate in the prior art. [Figure 2] 1 is a flowchart of a method for manufacturing a battery electrode plate according to an embodiment of the present application. [Figure 3] 1 is a structural schematic diagram of an electrode plate substrate in a first state in a method for manufacturing a battery electrode plate provided by an embodiment of the present application; FIG. [Figure 4] 2 is a structural schematic diagram of an electrode plate body in an embodiment of the present application. FIG. [Figure 5] 3 is a structural schematic diagram of a battery electrode plate in a second state in the method for manufacturing a battery electrode plate provided by an embodiment of the present application; FIG. [Figure 6] 1 is a schematic diagram of one structure of an electrode plate for a battery provided by an embodiment of the present application. [Figure 7]2 is a schematic diagram of another structure of a battery electrode plate provided by an embodiment of the present application; FIG. [Figure 8] FIG. 7 is a schematic diagram of the back surface structure of the battery electrode plate shown in FIG. 6. DETAILED DESCRIPTION OF THE INVENTION

[0032] In order to make the objectives, technical solutions and advantages of the present disclosure clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present disclosure with reference to the drawings of the embodiments of the present disclosure, and it should be understood that the described embodiments are only a part of the embodiments of the present disclosure, and not all of the embodiments thereof, and all other embodiments obtained by those skilled in the art based on the embodiments of the present disclosure without any creative work fall within the protection scope of the present disclosure.

[0033] 1a and 1b show a state of a battery electrode plate 100' cut when uneven cutting occurs in the conventional technology. In this case, the edge of the groove 120' for welding the tab 140' is a certain distance from the edge of the battery electrode plate 100', and a coating area is formed between the edge of the groove 120' and the edge of the battery electrode plate 100'. When the coating area is punched, a punching groove 101, which is a through groove, is formed. The side of the punching groove 101 near the edge of the battery has a notch structure, and the side near the groove 120' is directly connected to the groove 120'. Connected However, since the thickness at the position of the groove 120' is thinner and must withstand high-temperature welding when attaching the lug, stress concentration is likely to occur on the side of the punched groove 101 near the groove 120', which may cause the electrode plate to burst.

[0034] Hereinafter, a battery, a battery electrode plate, and a manufacturing method thereof according to embodiments of the present application will be described with reference to the drawings. For ease of explanation, a first direction F and a second direction S are defined as being perpendicular to each other in the plate surface direction of a plate-shaped electrode plate substrate. Here, the first direction F may be, for example, the width direction of the electrode plate substrate, and the second direction S may be, for example, the length direction of the electrode plate substrate. The direction perpendicular to the first direction F and the second direction S is defined as the thickness direction of the electrode plate substrate.

[0035] Furthermore, after the electrode plate body is manufactured from the electrode plate substrate, the width direction K of the electrode plate body becomes the first direction F of the electrode plate substrate, and the length direction L of the electrode plate body becomes the second direction S of the electrode plate substrate.

[0036] The electrode plate body may have a first edge 131 and a second edge 132 facing each other, and the width direction K of the electrode plate body extends from the first edge 131 to the second edge 132. cormorant The length direction L of the electrode plate body is perpendicular to the width direction K of the electrode plate body.

[0037] FIG. 2 is a flow chart of a method for manufacturing a battery electrode plate according to an embodiment of the present application, and FIG. 3 is a flow chart of a method for manufacturing a battery electrode plate according to an embodiment of the present application. electrode plate FIG. 2 is a structural schematic diagram of a substrate in a first state.

[0038] Referring to FIG. 2, the method for manufacturing a battery electrode plate of the present application includes steps S10 to S30, In step S10, a plurality of recessed grooves are provided on one surface of the electrode plate substrate at intervals in a first direction of the electrode plate substrate; In S20, the electrode plate substrate is cut along a plurality of cutting lines into a plurality of electrode plate bodies, and each groove is divided and cut along the cutting lines into a tab mounting groove and a first groove, and the tab mounting groove and the first groove divided and cut from the same groove are located in different electrode plate bodies; In S30, the tabs are welded into the tab mounting grooves of the electrode plate body to form the battery electrode plate.

[0039] Referring to Figure 3, multiple cutting lines 111 are arranged at intervals on the electrode plate substrate 110 along the first direction F, and the multiple cutting lines 111 are arranged in one-to-one correspondence with the grooves 120, and each cutting line 111 passes through the corresponding groove 120.

[0040] In the above solution, a groove 120 is formed in the electrode plate substrate 110, and the electrode plate substrate 110 is cut along a cutting line 111 that passes through the groove 120. When the tab mounting groove 121 and the first groove 122 are separated and cut from the groove 120, the edge of the tab mounting groove 121 inevitably communicates with a side edge, such as the first edge 131, of the battery electrode plate 100. The through groove punched out from the end of the tab mounting groove in the prior art can be changed to a tab mounting groove structure, which increases the thickness of the electrode plate body at that position, reducing the probability of rupture and improving the safety and reliability of the battery electrode plate.

[0041] Furthermore, in the present application, because the cutting line 111 is within the groove 120, even if the cutting line 111 is slightly misaligned, it is less likely to deviate from the groove 120, compared to the prior art in which the cutting line 111 is located at the edge of the tab mounting groove 121. That is, even if the cutting line 111 is misaligned, it will still be located within the groove 120. This effectively avoids the coating area between the edge of the battery electrode plate 100 and the edge of the tab mounting groove 121, ensures the thickness of the mounting area of ​​the battery electrode plate 100, and improves battery performance. This is also beneficial to the consistency of the interface of the battery electrode plate after formation, reducing battery safety risks.

[0042] 3, the electrode plate substrate 110 is a base material for producing the battery electrode plate 100. Since its size is larger than the battery electrode plate 100, at least two battery electrode plates 100 can be produced by cutting one electrode plate substrate 110. The electrode plate substrate 110 can include a current collector and an active material layer 133 formed on at least one surface of the current collector. For example, when forming a positive battery electrode plate, the electrode plate substrate 110 includes a positive electrode current collector and a positive electrode active material layer formed on at least one surface of the positive electrode current collector. However, when forming a negative battery electrode plate, the electrode plate substrate 110 includes a negative electrode current collector and a negative electrode active material layer formed on at least one surface of the negative electrode current collector.

[0043] The two ends of the electrode plate substrate 110 along the second direction S can form a winding head end and a winding tail end, that is, after the battery electrode plate 100 is manufactured from the electrode plate substrate 110, the two ends of the battery electrode plate 100 along the second direction S become the winding head end and the winding tail end at which the battery electrode plate 100 is wound.

[0044] In step S10, providing a plurality of grooves 120 on one surface of the electrode plate substrate 110 means providing a plurality of grooves 120 on the same surface of the electrode plate substrate 110, and a plurality of grooves 120 used for attaching tabs 140 can be provided on one surface of the electrode plate substrate 110. Specifically, the grooves 120 can be formed by washing away the active material layer 133 on the surface of the current collector.

[0045] Of course, the present application is not limited to providing multiple grooves 120 on only one surface of the electrode plate substrate 110, but recessed structures can also be provided on the surface of the electrode plate substrate 110 opposite the grooves 120.

[0046] For example, when welding the tab 140 by ultrasonic welding, in order to perform the ultrasonic welding smoothly, it is necessary to form an auxiliary groove that corresponds one-to-one with the above-mentioned groove 120 on the surface opposite the above-mentioned groove 120 of the electrode plate substrate 110.

[0047] In the present embodiment, the plurality of grooves 120 are spaced apart in the first direction F of the electrode plate substrate 110, for example, spaced apart at equal intervals in the first direction F. In this way, when battery electrode plates 100 are manufactured from the electrode plate substrate 110, each battery electrode plate 100 can have the same width. Furthermore, each groove 120 can be aligned in the first direction F, and the tabs 140 corresponding to the battery electrode plates 100 manufactured in this way can be attached to the same positions on the battery electrode plates 100.

[0048] The size of the groove 120 along the first direction F and the size of the groove 120 along the second direction S can be determined according to the size of the tab 140 to be actually attached.

[0049] In step S20, first, a cutting line 111 for the electrode plate substrate 110 is determined, and then the electrode plate substrate 110 is cut along the cutting line 111.

[0050] That is, the electrode plate substrate 110 can be cut into a plurality of electrode plate bodies 130 along a plurality of cutting lines 111, and the plurality of cutting lines 111 can be provided at intervals on the electrode plate substrate 110 along the first direction F. The plurality of cutting lines 111 can be parallel to each other, for example, the plurality of cutting lines 111 can all be parallel to the second direction S. The intervals between the respective cutting lines 111 can be equal so that battery electrode plates 100 of the same size can be cut.

[0051] In addition, it is necessary to provide a plurality of cutting lines 111 passing through the corresponding grooves 120 in one-to-one correspondence with the grooves 120.

[0052] 4 is a schematic diagram of the structure of an electrode plate body in an embodiment of the present application. Referring to FIGS. 3 and 4, because the cutting line 111 passes through the grooves 120, each groove 120 can be divided and cut into a tab mounting groove 121 and a first groove 122. Furthermore, in one electrode plate body 130, the tab mounting groove 121 is located at the first edge 131 of the electrode plate body 130, and the first groove 122 is located at the second edge 132 of the electrode plate body 130. In this case, the tab mounting groove 121 communicates with the widthwise edge K of the electrode plate body 130, for example, the first edge 131. Therefore, when the tab 140 is attached to the tab mounting groove 121 from the top side of the electrode plate body 130, the thickness of the attachment area of ​​the tab 140 is more uniform and no partial protrusion in the thickness direction occurs. This improves the flatness of the battery electrode plate 100 and enhances the battery performance.

[0053] Also, please note that since one groove 120 is cut and divided along one cutting line 111, the tab mounting groove 121 and the first groove 122, which are cut and divided from the same groove 120, are located on different electrode plate bodies 130.

[0054] In one electrode plate substrate 110, three electrode plate bodies 130 and the strip-shaped electrode plates located at the top and bottom can be cut along the four cutting lines 111 shown in FIG. 3. Department Since the strip-shaped electrode plate does not have a tab mounting groove 121, it can be discarded without being used. The bottommost strip-shaped electrode plate does not have the first groove 122 formed therein, The strip-shaped electrode plate located on the bottom side has a tab mounting groove 121 formed therein, so it can be understood that it can be used as a battery electrode plate 100 after the tab is welded thereto.

[0055] In the embodiment of the present application, when the spacing between each cutting line 111 is equal, each groove 120 can have the same size along the first direction F, and each cutting line 111 can be located at the same position of the corresponding groove 120 along the first direction F.

[0056] In step S30, in addition to the electrode plate body 130 shown in FIG. 4, a tab 140 can be welded into the tab mounting groove 121 of the electrode plate body 130 to form a battery electrode plate in a second state shown in FIG. 5.

[0057] In the embodiment of the present application, in the electrode plate body 130, the tab mounting groove 121 can be used to mount the tab 140, and the first groove 122 is a structure that is inevitably generated during processing. In order to improve insulation, after step S30, in addition to the battery electrode plate in the second state shown in FIG. 5, a first insulating layer 151 can be covered at the groove opening position of the tab mounting groove 121 where the tab 140 is mounted, and a second insulating layer 152 can be covered at the groove opening position of the first groove 122, thereby forming the battery electrode plate 100 shown in FIG. 6.

[0058] Alternatively, the first insulating layer 151 may be provided at the groove opening of the tab mounting groove 121, and at the same time, the first insulating layer 151 may also be provided on the side of the electrode plate body 130 opposite the tab mounting groove 121. The first insulating layer 151 may be provided at the groove opening of the first groove 122, and at the same time, the first insulating layer 151 may also cover the side of the electrode plate body 130 opposite the first groove 122.

[0059] The size of the first insulating layer 151 is set to a size that can completely cover the opening of the tab mounting groove 121, and the size of the second insulating layer 152 is set to a size that can completely cover the opening of the first groove 122. In this solution, by covering the first groove 122 with the second insulating layer 152, problems with burrs and dust generated during the punching process are avoided, the risk of battery short circuits is reduced, and the quality of the cell is improved.

[0060] FIG. 7 is a schematic diagram of another structure of a battery electrode plate provided by an embodiment of the present application.

[0061] In this embodiment of the present application, after step S30, in addition to the battery electrode plate in the second state shown in Fig. 5, a notch 153 can be punched at the position where the first groove 122 is formed in the electrode plate body 130. There is an active material layer on the current collector surface around the notch 153, and the electrode plate in this area is thick and less likely to burst.

[0062] 7 can be formed by covering the opening of the tab mounting groove 121 to which the tab 140 is attached with a first insulating layer 151. Alternatively, the opening of the tab mounting groove 121 and the side of the electrode plate body 130 opposite the tab mounting groove 121 can be covered with the first insulating layer 151 at the same time.

[0063] In the embodiment of the present application, the insulating measure at the position of the first groove 122 can be determined depending on the size of the notch 153 .

[0064] For example, when the first groove 122 is completely punched out, there is no need to provide an insulating film at the position of the notch 153 as shown in FIG.

[0065] Alternatively, if the first groove 122 is completely punched out, a second insulating layer (not shown) is provided at the location of the notch 153 .

[0066] Alternatively, if the first groove 122 is not completely punched out, a second insulating layer (not shown) is provided at the location of the notch 153 .

[0067] When the second insulating layer is provided, the size of the second insulating layer must be larger than the size of the notch 153, that is, the second insulating layer must completely cover the notch 153.

[0068] Referring to FIG. 5, the above-mentioned battery electrode plate 100 has a size L1 of the tab mounting groove 121 along the first direction F (corresponding to the width direction K of the electrode plate body), a size L2 of the first groove 122 along the first direction F, a size D of both the tab mounting groove 121 and the first groove 122 along the second direction S (corresponding to the length direction L of the electrode plate body), a size W of the tab 140 along the second direction S, and a size Z of the electrode plate substrate 110 along the second direction S. The size of each structure must satisfy the following conditions: L1 ≥ L2, L1 = (0.1 ~ 0.6) × Z, L2 is 0.1mm to 15.0mm. D=(1.0~4.0)×W.

[0069] Hereinafter, two specific examples will be given to explain the method of manufacturing the battery electrode plate 100.

[0070] Example 1:

[0071] An electrode plate substrate 110 of model number 473590, which has a size of 83 mm along the first direction F, is selected, and a groove 120, which has a size of 25 mm along the first direction F and a size of 10 mm along the second direction S, is washed in a specified area of ​​the electrode plate substrate 110. After cutting the electrode plate substrate 110 along the cutting line 111, the tab mounting groove 121 and the first groove 122 are cut apart from the recessed groove 120, and the tab mounting groove 121 has a size of 22 mm along the first direction F, the first groove 122 has a size of 3 mm along the first direction F, and the size of the tab mounting groove 121 along the second direction S and the size of the first groove 122 along the second direction S are both 10 mm. The tab 140 has a size of 6 mm along the second direction S, and is welded into the tab mounting groove 121 . A first insulating layer 151 is provided at the groove opening of the tab mounting groove 121 and at a position opposite the tab mounting groove 121 on the electrode plate body 130, and a second insulating layer 152 is provided at the groove opening of the first groove 122 and at a position opposite the first groove 122 on the electrode plate body 130. The first insulating layer 151 is 26 mm in size along the first direction F and 16 mm in size along the second direction S, and the second insulating layer 152 is 6 mm in size along the first direction F and 16 mm in size along the second direction S.

[0072] After the above battery electrode plate fabrication is completed, the positive battery electrode plate, separator layer, and negative battery electrode plate can be wound together to form a wound cell.

[0073] Example 2

[0074] An electrode plate substrate 110 of model number 473590, which has a size of 83 mm along the first direction F, is selected, and a groove 120, which has a size of 25 mm along the first direction F and a size of 10 mm along the second direction S, is flushed in a predetermined area of ​​the electrode plate substrate 110. After cutting the electrode plate substrate 110 along the cutting line 111, the recessed groove 120 is divided and cut into a tab mounting groove 121 and a first groove 122, the tab mounting groove 121 having a size of 22 mm along the first direction F, the first groove 122 having a size of 3 mm along the first direction F, and the size of the tab mounting groove 121 along the second direction S and the size of the first groove 122 along the second direction S are both 10 mm. The size of the tab 140 along the second direction S is 6 mm, and the tab 140 is welded into the tab mounting groove 121 . A first insulating layer 151 having a size of 26 mm along the first direction and a size of 16 mm along the length direction is provided at the groove opening of the tab mounting groove 121 and at a position opposite the tab mounting groove 121 on the electrode plate body 130, respectively. At the position where the first groove 122 is formed on the electrode plate body 130, a die punching means is used to form a notch 153 at the position of the first groove 122, having a size of 5 mm along the first direction F and a size of 12 mm along the second direction S, thereby ensuring that the first groove 122 is completely punched out.

[0075] After the above battery electrode plate fabrication is completed, the positive battery electrode plate, separator layer, and negative battery electrode plate can be wound together to form a wound cell.

[0076] The present embodiment further provides an electrode plate 100 for a battery.

[0077] Referring to FIG. 6, the battery electrode plate 100 includes an electrode plate body 130 provided with a tab attachment groove 121 and a first groove 122, and a tab 140.

[0078] For example, the electrode plate body 130 has a first edge 131 and a second edge 132 along its width direction K, and the tab mounting groove 121 communicates with the first edge 131 of the electrode plate body 130, and the first groove 122 communicates with the second edge 132 of the electrode plate body 130. The tab 140 is connected within the tab mounting groove 121.

[0079] In other words, the edge of the tab mounting groove 121 is close to the first edge 131 of the electrode plate body 130, and the entire groove of the tab mounting groove 121 extends straight to the first edge 131 of the electrode plate body 130. As a result, there is no punched-out through-groove between the edge of the battery electrode plate 100 and the edge of the tab mounting groove 121. That is, the through-groove structure provided at the end of the tab welding groove in the prior art is replaced by the tab mounting groove 121, and the electrode plate body 130 is thicker at that position, which reduces the probability of rupture and improves the safety and reliability of the battery electrode plate 100.

[0080] Furthermore, a first groove 122 is formed in the battery electrode plate 100, and the entire first groove 122 is a through groove, and the structural layer at the groove opening edge of the first groove 122 comprises a current collector and an active material layer covering the front and back surfaces of the current collector, and is thick and strong, so it can be understood that the electrode plate is unlikely to burst at that location.

[0081] In the embodiment of the present application, in the direction from the second edge 132 toward the first edge 131, i.e., along the width direction K of the electrode plate body 130, the projection of the first groove 122 on the first edge 131 covers at least a portion of the projection of the tab mounting groove 121 on the first edge 131. This means that the positions of the first groove 122 and the tab mounting groove 121 at least partially overlap in the length direction of the electrode plate body 130, but it is understood that the present application is not limited to this, and the positions of the first groove 122 and the tab mounting groove 121 may be completely aligned in the length direction of the electrode plate body 130.

[0082] Also, referring to Figure 6, as mentioned above, since the first groove 122 is connected to the second edge 132 of the electrode plate body 130, the first groove 122 has a groove opening located at the second edge 132, and the length D of the groove opening of the first groove 122 along the direction parallel to the first edge 131 is greater than the width W of the tab 140. In addition, the tab mounting groove 121 communicates with the first edge 131 of the electrode plate body 130, and the tab mounting groove 121 has an opening located at the first edge 131, and the length of the opening along a direction parallel to the first edge 131 is equal to the length of the groove opening.

[0083] 7, tab attachment groove 121 has an opening located at first edge 131, and a length D2 of the opening of tab attachment groove 121 along a direction parallel to first edge 131 is smaller than a length D1 of the groove opening of first groove 122. This corresponds to the case where first groove 122 is formed by punching.

[0084] It should also be understood that the electrode plate body 130 may include a current collector and an active material layer 133 formed on at least one surface of the current collector. For example, when forming a positive battery electrode plate, the electrode plate body 130 includes a positive current collector and a positive active material layer formed on at least one surface of the positive current collector. When forming a negative battery electrode plate, the electrode plate body 130 includes a negative current collector and a negative active material layer formed on at least one surface of the negative current collector. In the present application, the tab attachment groove 121 and the first groove 122 can be formed by washing away the active material layer 133 on the current collector surface. The current collector may be copper foil, aluminum foil, nickel foil, copper mesh, aluminum mesh, carbon-coated copper foil, carbon-coated aluminum foil, or a polymer current collector having a conductive layer formed on or within the polymer.

[0085] It can be understood that when the tab mounting groove 121 and the first groove 122 are formed on the same surface of the electrode plate body 130, the area between the tab mounting groove 121 and the first groove 122 should have an active material layer 133.

[0086] Furthermore, referring to FIG. 6, in the direction from the first edge 131 to the second edge 132, i.e., along the width direction K of the electrode plate body 130, the width L3 of the active material layer 133 between the tab mounting groove 121 and the first groove 122 should be greater than the sum of the width L1 of the tab mounting groove 121 and the width L2 of the first groove 122.

[0087] In the present embodiment, as described above, the tab mounting groove 121 has an opening located at the first edge 131, and when the tab mounting groove 121 is formed in the active material layer 133, the bottom of the tab mounting groove 121 is the current collector, and the three sides of the tab mounting groove 121 are the active material layer 133.

[0088] FIG. 8 is a schematic diagram of the back surface structure of the battery electrode plate shown in FIG.

[0089] In one possible embodiment, the active material layer 133 may be provided on either of the two surfaces of the current collector. Referring to the schematic diagram of the back surface of a battery electrode plate 200 shown in FIG. 8, the active material layer 133 on the surface of the current collector opposite the tab mounting groove 121 is provided with a second tab mounting groove 124 (the tab mounting groove 121 is shown by a dashed line) that is arranged to face the tab mounting groove 121. Along the length direction L of the electrode plate body 130, the length D2' of the second tab mounting groove 124 is greater than the length D2 of the tab mounting groove 121, and along the width direction K of the electrode plate body 130, the width L1' of the second tab mounting groove 124 is greater than the width L1 of the tab mounting groove 121.

[0090] Depending on the arrangement of the tab attachment groove 121, the bottom of the first groove 122 is the current collector, and the periphery of the first groove 122 is the active material layer.

[0091] In addition, in one possible embodiment, when an active material layer 133 is provided on both of the two surfaces of the current collector, the active material layer 133 on the surface opposite the first groove 122 of the current collector is provided with a second groove 123 (the first groove 122 is shown by a dashed line) arranged opposite the first groove 122, and in the longitudinal direction L of the electrode plate body 130, the length D' of the second groove 123 is greater than the length D of the first groove 122, and in the width direction K of the electrode plate body 130, the width L2' of the second groove 123 is greater than the width L2 of the first groove 122.

[0092] In the present embodiment, as described above, active material layers 133 are provided on both surfaces of the current collector, tab mounting grooves 121 are provided in the active material layers 133 on one side, tabs 140 are welded to the current collector, and the welding points on the surface of the current collector opposite tabs 140 are covered by active material layers 133. This achieves the purpose of insulating and protecting the welding points.

[0093] For example, the first groove 122 is located on the same side of the active material layer 133 as the tab attachment groove 121, and the other side of the current collector facing the first groove 122 also has an active material layer 133. In other words, the electrode plate body is not penetrated by the first groove 122, and the side of the electrode plate body 130 opposite the first groove 122 also has an active material layer 133.

[0094] In the present embodiment, referring to FIG. 6, the tab mounting groove 121 in which the tab 140 is accommodated is covered with a first insulating layer 151 in order to insulate the tab 140 .

[0095] Also, referring to Figure 8, when the second tab mounting groove 124 is provided on the surface opposite the tab mounting groove 121 of the electrode plate body 130, the second tab mounting groove 124 is provided so as to face the tab mounting groove 121, the second tab mounting groove 124 is covered with the fifth insulating layer 155, and the portions of the first insulating layer 151 and the fifth insulating layer 155 that extend beyond the first edge 131 are bonded to each other.

[0096] 7, the first groove 122 can communicate with the second edge 132. When the battery electrode plate is manufactured using the above-described electrode plate manufacturing method, the first groove 122 is a structure that is inevitably generated when the tab mounting groove 121 is cut.

[0097] The electrode plate body 130 has two ends along the length direction L of the electrode plate body that can form a winding head end and a winding tail end, that is, the two ends along the length direction L of the electrode plate body 130 become the winding head end and the winding tail end around which the battery electrode plate 100 is wound.

[0098] In one possible embodiment, the tab attachment groove 121 and the first groove 122 are located at the same position in the longitudinal direction L of the electrode plate body. Furthermore, the tab attachment groove 121 and the first groove 122 have the same extension length in the longitudinal direction L of the electrode plate body. This makes it possible to easily cut the electrode plate body 130 from the electrode plate substrate 110.

[0099] For example, the first groove 122 penetrates the electrode plate body 130 along the thickness direction of the battery electrode plate 100, that is, the first groove is a through groove.

[0100] In another possible embodiment, the depth of the first grooves 122 is smaller than the thickness of the electrode plate body 130 , and the openings of the first grooves 122 are covered with the second insulating layer 152 .

[0101] As described above, the battery electrode plate 100 has the first groove 122 and the second groove 123 that are provided opposite each other, and the tab mounting groove 121 and the second tab mounting groove 124 that are provided opposite each other. This makes it easy to mount the tab 140 in the tab mounting groove 121 by ultrasonic welding. It can be understood that if the tab is welded into the tab mounting groove 121 by laser welding, the second groove 123 and the second tab mounting groove 124 do not need to be provided.

[0102] For example, the size of the tab mounting groove 121 along the width direction K of the electrode plate body is L1, the size of the first groove 122 along the width direction K of the electrode plate body is L2, the size of the tab mounting groove 121 and the first groove 122 along the length direction L of the electrode plate body are both D, the size of the tab along the length direction L of the electrode plate body is W, and the size of the electrode plate base material along the length direction L of the electrode plate body is Z, L1 ≥ L2, L1 = (0.1 ~ 0.6) × Z, L2 is 0.1mm to 15.0mm. The condition D = (1.0~4.0) × W is met.

[0103] It is understood that the battery electrode plate 100 of the embodiment of the present application may be manufactured by the above-mentioned manufacturing method of a battery electrode plate, or may be obtained by processing by other methods, but the present application is not limited thereto.

[0104] Referring to FIG. 7, the tab 140 has a first step 141 positioned within the tab mounting groove 121 and a second step 142 extending from the tab mounting groove 121, with a tab adhesive 143 provided on the second step 142, and a first insulating layer 151 covering a portion of the tab adhesive 143.

[0105] Referring to FIG. 6, in one possible embodiment, the second insulating layer 152 extends beyond the second edge 132 by a distance of less than 3 mm.

[0106] An embodiment of the present application further provides a battery comprising a case and a wound cell enclosed within the case. Illustratively, the case can be an aluminum plastic film case.

[0107] The wound cell is formed by stacking a first electrode plate, a separator, and a second electrode plate, and then winding them together, and the first electrode plate and the second electrode plate have opposite polarities, and the first electrode plate can be the above-mentioned battery electrode plate. Also, since the structure and functional principles of the battery electrode plate have been described in detail above, they will not be described again here.

[0108] For example, in the above-described battery, the surface of the active material layer of the second electrode plate facing the tab mounting groove 121 is covered with a third insulating layer. Also, the surface of the active material layer of the second electrode plate facing the first groove is covered with a fourth insulating layer. This allows for insulation protection between the first and second electrode plates.

[0109] In describing this disclosure, unless otherwise specified, it should be understood that the terms "attach," "couple," and "connect" should be understood broadly and may refer to, for example, a fixed connection, an indirect connection through an intermediate medium, or an internal communication between two components or an interactive relationship between two components. Those skilled in the art may understand the specific meaning of the above terms in this disclosure depending on the particular situation.

[0110] In describing the present disclosure, it should be understood that orientations or positional relationships indicated by terms such as "upper," "lower," "front," "rear," "vertical," "horizontal," "top," "bottom," "inner," "outer," etc. are based on orientations or positional relationships shown in the drawings, are intended merely to facilitate explanation and simplification of the present disclosure, and do not expressly or imply that the devices or elements shown must have a particular orientation, be configured, or operate in a particular orientation, and therefore cannot be understood as limiting the present disclosure.

[0111] The terms "first," "second," "third," "fourth," etc. (when present) in the specification and claims of this application, and in the drawings described above, are intended to distinguish between similar objects and are not necessarily intended to describe a particular order or sequence. It should be understood that the data used in such a manner may be appropriately interchanged so that the embodiments of this application described herein, for example, can be practiced in orders other than those shown or described herein.

[0112] Additionally, the terms "comprise" and "have," and all variations thereof, are intended to cover non-exclusive inclusions, for example, a process, method, system, product, or device comprising a series of steps or units need not be limited to the steps or units explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to the process, method, product, or device.

[0113] Finally, it should be noted that the above embodiments are used to explain the technical solutions of the present disclosure, but are not intended to limit the same. The present disclosure will be described in detail with reference to the above embodiments. However, those skilled in the art can still modify the technical solutions described in the above embodiments or make equivalent substitutions for some or all of the technical features thereof, and such modifications or substitutions will not cause the essence of the corresponding technical solutions to depart from the scope of the technical solutions of the embodiments of the present disclosure.

[0114] This application claims priority from a Chinese patent application filed with the China Patent Office on September 9, 2021, bearing application number 202111053876.9 and entitled "Battery electrode plate, battery, and method for manufacturing battery electrode plate," the entire contents of which are incorporated herein by reference. [Explanation of symbols]

[0115] Electrode plate for 100, 100', 200 batteries 101 punching groove 110 Electrode plate base material 111 Cutting line 120, 120' groove 121 Tab mounting groove 122 First groove 123 Second groove 124 Second tab mounting groove 130, 130' electrode plate body 131 First Edge 132 Second Edge 133 Active material layer 140, 140' tab 141 Stage 1 142 2nd stage 143 Tab Adhesive 151 First insulating layer 152 Second insulating layer 153 Notch 155 5th insulating layer

Claims

1. The electrode plate body includes an electrode plate body and a tab, the electrode plate body having a tab mounting groove communicating with a first edge of the electrode plate body and a first groove communicating with a second edge of the electrode plate body, the first edge and the second edge being two opposing edges of the electrode plate body, and the tab being connected within the tab mounting groove; The tab mounting groove has a size L1 along the width direction of the electrode plate body, and the first groove has a size L2 along the width direction of the electrode plate body, where L1>L2; The electrode plate for a battery, wherein the first groove is a through groove that penetrates the electrode plate along a thickness direction of the electrode plate.

2. 2. The battery electrode plate according to claim 1, wherein a projection of the first groove on the first edge covers at least a portion of a projection of the tab mounting groove on the first edge along a direction from the second edge toward the first edge.

3. the first groove has an opening located at the second edge, and the length of the opening of the first groove along a direction parallel to the first edge is greater than the width of the tab; and / or 2. The battery electrode plate according to claim 1, wherein the tab mounting groove has an opening located at the first edge, the first groove has a groove mouth located at the second edge, and a length of the opening is less than or equal to a length of the groove mouth along a direction parallel to the first edge.

4. the electrode plate body includes a current collector and an active material layer provided on at least one surface of the current collector, and the active material layer is provided in a region between the tab attachment groove and the first groove; 2. The battery electrode plate according to claim 1, wherein a width of the active material layer between the tab attachment groove and the first groove along a direction from the first edge toward the second edge is greater than a sum of the widths of the tab attachment groove and the first groove.

5. 5. The battery electrode plate according to claim 4, wherein the tab mounting groove has an opening positioned at the first edge, a bottom of the tab mounting groove is the current collector, and three peripheral sides of the tab mounting groove are active material layers.

6. an active material layer is provided on each of two surfaces of the current collector, and a second tab mounting groove is provided in the active material layer on the surface of the current collector opposite the tab mounting groove so as to face the tab mounting groove; The length of the second tab mounting groove is greater than the length of the tab mounting groove along the length direction of the electrode plate body, and / or the width of the second tab mounting groove is greater than the width of the tab mounting groove along the width direction of the electrode plate body, 6. The electrode plate for a battery according to claim 5, wherein the width direction of the electrode plate body is a direction from the first edge toward the second edge, and the length direction of the electrode plate body is perpendicular to the width direction.

7. 5. The battery electrode plate according to claim 4, wherein the first groove has a groove opening located at the second edge, a bottom of the first groove is the current collector, and a peripheral side of the first groove is the active material layer.

8. an active material layer is provided on each of two surfaces of the current collector, and a second groove is provided in the active material layer on the surface of the current collector opposite to the first groove, the second groove being provided so as to face the first groove; The length of the second groove is greater than the length of the first groove along the length direction of the electrode plate body, and / or the width of the second groove is greater than the width of the first groove along the width direction of the electrode plate body, 8. The battery electrode plate according to claim 7, wherein the width direction of the electrode plate body is a direction from the first edge toward the second edge, and the length direction of the battery electrode plate is perpendicular to the width direction.

9. 5. The battery electrode plate according to claim 4, wherein an active material layer is provided on each of two surfaces of the current collector, the tab attachment groove is provided in the active material layer on one of the surfaces, the tab is welded to the current collector, and the welding point on the surface of the current collector opposite the tab is covered with the active material layer.

10. 10. The battery electrode plate according to claim 9, wherein the first groove is located on the same side of the active material layer as the tab attachment groove, and the other surface of the current collector facing the first groove has an active material layer.

11. The tab mounting groove in which the tab is accommodated is covered with a first insulating layer, and / or the first groove is covered with a second insulating layer; 4. The battery electrode plate according to claim 1, wherein the second insulating layer extends beyond the second edge by a distance of less than 3 mm.

12. 12. The battery electrode plate according to claim 11, wherein the tab has a first step positioned within the tab mounting groove and a second step extending from the tab mounting groove, a tab adhesive is provided on the second step, and the first insulating layer covers a portion of the tab adhesive.

13. 12. The battery electrode plate according to claim 11, wherein a second tab mounting groove is provided on a surface of the battery electrode plate opposite the tab mounting groove so as to face the tab mounting groove, the second tab mounting groove is covered with a fifth insulating layer, and portions of the first insulating layer and the fifth insulating layer that extend beyond the first edge are bonded to each other.

14. The tab mounting groove and the first groove each have a size D along the length direction of the electrode plate body, the tab has a size W along the length direction of the electrode plate body, and the electrode plate base material has a size Z along the length direction of the electrode plate body, where L1=(0.1 to 0.6)×Z. L2 is 0.1 mm to 15.0 mm, 4. The battery electrode plate according to claim 1, wherein the condition D=(1.0 to 4.0)×W is satisfied.

15. A battery comprising a cell formed by stacking a first electrode plate, a separator, and a second electrode plate and then winding the stacked electrodes, wherein the first electrode plate and the second electrode plate have opposite polarities, A battery, wherein the first electrode plate is the battery electrode plate according to any one of claims 1 to 10.

16. a surface of the active material layer of the second electrode plate facing the tab mounting groove is covered with a third insulating layer; 16. The battery according to claim 15, wherein a surface of the active material layer of the second electrode plate facing the first groove is covered with a fourth insulating layer.

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