Electrode plate, battery cell and full-tab battery

Abstract

The utility model provides an electrode plate, a battery cell and a full-tab battery. The electrode plate comprises an electrode plate substrate, an active conducting layer and an insulating layer, the active conducting layer is arranged in a coating area, and the coating area is provided with a winding starting end and a winding ending end; a head insulator layer and a tail insulator layer of the insulating layer are arranged on the blank area at intervals, the head insulator layer is located on the first side, close to the winding starting end, of the blank area, the tail insulator layer is located on the second side, close to the winding ending end, of the blank area, and the height of the head insulator layer and the height of the tail insulator layer are both smaller than the height of the blank area. According to the electrode plate, the head insulator layer is arranged adjacent to the winding starting end, the tail insulator layer is arranged adjacent to the winding ending end, and a gap can be formed between the head insulator layer and the tail insulator layer, so that the use amount of the insulating layers is reduced, and a certain supporting effect on the battery cell is achieved, so that the phenomenon that the battery cell is excessively twisted is avoided; and moreover, the safety of the full-tab battery is improved, and the reject ratio of the K value of the battery cell is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of full-tab battery production, in particular to an electrode sheet, a battery core and a full-tab battery. Background Art

[0002] The full-tab battery is also called the "tab-free battery". It uses the flattening technology to flatten the current collector foil (tab) at both ends of the battery cell, and then welds the current collector plates on both sides of the winding core, so that the entire positive / negative current collector can be turned into tabs to prepare a full-tab battery. The battery cell is an extremely important component of the full-tab battery, and its quality directly determines the overall electrical performance of the full-tab battery. Therefore, the production of the battery cell is particularly important.

[0003] In actual applications, the steps of making a battery cell include: first, coating the positive / negative active materials on the current collectors respectively, then drying and cutting to obtain the positive / negative electrode sheets required for production, i.e., electrode sheets, and then winding the electrode sheets, separators, and negative electrode sheets to obtain a battery cell. However, in the process of making a battery cell, burrs are likely to appear on both sides of the cut positive / negative electrode sheets, which may easily pierce the separator after long-term use, causing a short circuit in the battery cell.

[0004] In order to solve the above-mentioned technical problems, a new type of electrode plate has appeared on the market. For example, Chinese patent No. CN112490407 A discloses an electrode plate and its preparation method and a lithium-ion battery, and specifically discloses an electrode plate, including a current collector, an electrode layer and an insulating layer, the electrode layer is stacked on the current collector; the insulating layer is stacked on the current collector and abuts against the electrode layer, and the insulating layer includes dioctyl terephthalate, so that the added insulating layer can prevent burrs from piercing the plate and causing a short circuit.

[0005] Although the insulating layer added to the electrode plate can effectively prevent the burr from piercing the electrode plate and causing a short circuit, since the insulating layer and the electrode layer are both in strip shape, the extending direction of the insulating layer is the same as the extending direction of the electrode layer, and the insulating layer is in the same direction as the electrode layer. Figure 1 It can be seen that the insulating layer is continuously arranged on both sides of the electrode layer, which easily causes the overall weight of the battery cell to be heavier, which is not conducive to the development of lightweight lithium batteries, and also causes higher production costs. It also causes the thickness of the battery cell ends to be thicker, which is not conducive to the flattening operation of the full-tab battery, resulting in the two ends of the battery cell being easily over-kneaded or uneven after flattening. Utility Model Content

[0006] The purpose of the utility model is to overcome the shortcomings of the prior art and to provide an electrode sheet, a battery cell and a full-tab battery which can reduce the usage of an insulating layer, provide better support for the ends of the battery cell, effectively avoid the phenomenon of over-kneading of the battery cell, improve the safety of the full-tab battery, and reduce the defective rate of the battery cell K value.

[0007] The purpose of this utility model is achieved through the following technical solutions:

[0008] An electrode sheet comprises an electrode sheet substrate, an active conductive layer and an insulating layer, wherein a first surface of the electrode sheet substrate comprises a coating area and a blank area, and the active conductive layer is arranged on the coating area.

[0009] The coating area has a winding start end and a winding end end;

[0010] The insulating layer includes a head insulating sublayer and a tail insulating sublayer, and the head insulating sublayer and the tail insulating sublayer are spaced apart on the blank area. The head insulating sublayer is located on a first side of the blank area adjacent to the starting end of the winding, and the tail insulating sublayer is located on a second side of the blank area adjacent to the ending end of the winding, and the heights of the head insulating sublayer and the tail insulating sublayer are both smaller than the height of the blank area.

[0011] In one embodiment, the number of the head insulating sub-layers is two, and the blank area includes a first edge blank sub-area and a second edge blank sub-area, and the first edge blank sub-area and the second edge blank sub-area are respectively located on both sides of the coating area; the two head insulating sub-layers are respectively arranged on the first edge blank sub-area and the second edge blank sub-area.

[0012] In one of the embodiments, the number of the tail insulating sub-layers is two, and the two tail insulating sub-layers are respectively located on the first edge blank sub-region and the second edge blank sub-region.

[0013] In one of the embodiments, one end of the head insulating sublayer abuts against the active conductive layer.

[0014] In one of the embodiments, one end of the tail insulating sublayer abuts against the active conductive layer.

[0015] In one embodiment, the insulating layer is a ceramic insulating layer.

[0016] In one embodiment, the thickness of the head insulating sublayer is 5um to 50um, the width is 2mm to 4mm and the length is 220mm to 260mm; and / or,

[0017] The tail insulating sublayer has a thickness of 5um to 50um, a width of 2mm to 4mm and a length of 220mm to 260mm.

[0018] In one embodiment, the distance between the head insulating sublayer and the tail insulating sublayer is 1980 mm to 2340 mm; and / or,

[0019] The height difference between the head insulating sublayer and the blank area is 7 mm to 8 mm; and / or,

[0020] The height difference between the tail insulating sublayer and the blank area is 7 mm to 8 mm; and / or,

[0021] The blank area is extended along the length direction of the coating area; and / or,

[0022] The number of the active conductive layers is multiple; and / or,

[0023] The second surface of the pole piece substrate is provided with the coating area, the blank area, the active conductive layer and the insulating layer.

[0024] A battery cell comprises a positive electrode sheet and a negative electrode sheet, wherein the positive electrode sheet and / or the negative electrode sheet adopts the electrode sheet described in any of the above embodiments.

[0025] A full-tab battery comprises the battery cell described in any one of the above embodiments.

[0026] Compared with the prior art, the utility model has at least the following advantages:

[0027] 1) Since the head insulating sublayer and the tail insulating sublayer are arranged on the blank area at intervals, a gap can be formed between the head insulating sublayer and the tail insulating sublayer, thereby reducing the use of the insulating layer in the middle of the blank area. In this way, it is ensured that the overall weight of the battery cell will not change significantly, which is conducive to the development of lightweight lithium batteries and reduces production costs. It also ensures that the thickness of the end of the battery cell is thinner, which is more conducive to the flattening operation of the full-tab battery. Since the height of the head insulating sublayer and the tail insulating sublayer are both less than the height of the blank area, gaps are formed between the head insulating sublayer and the tail insulating sublayer and the edges of the blank area, that is, the head insulating sublayer and the tail insulating sublayer do not completely cover the blank area, so as to ensure that the end of the battery cell formed by subsequent winding can conduct electricity, thereby ensuring the normal operation of the full-tab battery.

[0028] 2) Since the head insulating sublayer is arranged on the first side of the blank area adjacent to the winding starting end, the head insulating sublayer is arranged adjacent to the winding starting end, and the tail insulating sublayer is arranged on the second side of the blank area adjacent to the winding ending end, the tail insulating sublayer is arranged adjacent to the winding ending end. After the electrode sheet is wound, the head insulating sublayer is located inside the battery cell, and the tail insulating sublayer is located outside the battery cell. In this way, on the one hand, it can provide better support for the end of the battery cell to ensure that the battery cell will not be over-kneaded after the flattening operation. On the other hand, the additional insulating layer can also effectively avoid the battery cell from short-circuiting due to the misalignment of the end end of the positive electrode sheet and the end end of the negative electrode sheet after winding, thereby improving the safety of the full-ear battery. On the other hand, the additional insulating layer can also provide better protection for the winding starting end and the winding ending end of the first side of the electrode sheet substrate, effectively improving the phenomenon that the burrs pierce the diaphragm at the winding starting end and the winding ending end to cause local short-circuiting of the battery, thereby reducing the defective rate of the battery cell K value. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the utility model and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying creative work.

[0030] Figure 1 A schematic diagram of the structure of an electrode sheet in one direction according to an embodiment of the utility model;

[0031] Figure 2 This is a schematic diagram of the structure of an electrode sheet in one direction according to another embodiment of the utility model;

[0032] Figure 3 for Figure 2 A cross-sectional view of the electrode sheet shown in one direction;

[0033] Figure 4 for Figure 3 A partial enlarged view shown in the middle.

[0034] Figure numerals: 10, electrode sheet; 100, electrode sheet substrate; 110, first side of electrode sheet substrate; 111, coating area; 1111, winding starting end; 1112, winding ending end; 112, blank area; 1121, first edge blank sub-area; 1122, second edge blank sub-area; 120, second side of electrode sheet substrate; 200, active conductive layer; 300, insulating layer; 310, head insulating sub-layer; 320, tail insulating sub-layer. DETAILED DESCRIPTION

[0035] In order to facilitate the understanding of the present invention, the present invention will be described more comprehensively with reference to the relevant drawings. The drawings provide preferred embodiments of the present invention. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thoroughly and comprehensively understood.

[0036] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only and do not represent the only implementation method.

[0037] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art in the technical field of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0038] In order to better understand the technical solutions and beneficial effects of the present invention, the present invention is further described in detail below in conjunction with specific embodiments:

[0039] like Figures 1 to 3 As shown, an electrode sheet 10 of an embodiment includes an electrode sheet substrate 100, an active conductive layer 200 and an insulating layer 300, the first surface 110 of the electrode sheet substrate includes a coating area 111 and a blank area 112, the active conductive layer 200 is arranged on the coating area 111, and the coating area 111 has a winding starting end 1111 and a winding ending end 1112; the insulating layer 300 includes a head insulating sublayer 310 and a tail insulating sublayer 320, the head insulating sublayer 310 and the tail insulating sublayer 320 are arranged on the blank area 112 at intervals, the head insulating sublayer 310 is located on a first side of the blank area 112 adjacent to the winding starting end 1111, the tail insulating sublayer 320 is located on a second side of the blank area 112 adjacent to the winding ending end 1112, and the heights of the head insulating sublayer 310 and the tail insulating sublayer 320 are both smaller than the height of the blank area 112.

[0040] It can be understood that since the first side 110 of the electrode substrate includes a coating area 111 and a blank area 112, the active conductive layer 200 can be located in the coating area 111, and the insulating layer 300 is located in the blank area 112, so as to facilitate subsequent coating, so as to realize the arrangement of the active conductive layer 200 and the insulating layer 300 on the first side of the electrode sheet 10. Since the coating area 111 has a winding start end 1111 and a winding end end 1112, on the one hand, it is convenient for subsequent winding, and on the other hand, it provides a positioning function for the insulating layer 300, so that the head insulating sublayer 310 and the tail insulating sublayer 320 can be arranged at the winding start end 1111 and the winding end end 1112 respectively; since the head insulating sublayer 310 and the tail insulating sublayer 320 are arranged at intervals on the blank area 112, a gap can be formed between the head insulating sublayer 310 and the tail insulating sublayer 320, thereby reducing the use of the insulating layer 300 in the middle of the blank area 112, thus ensuring that the overall weight of the battery cell is not There will be a big change, which is beneficial to the development of lightweight lithium batteries, and it also reduces the production cost, and ensures that the thickness of the end of the battery cell is thinner, which is more conducive to the flattening operation of the full-tab battery. Because the height of the head insulating sublayer 310 and the tail insulating sublayer 320 are both smaller than the height of the blank area 112, the head insulating sublayer 310 and the tail insulating sublayer 320 form gaps with the edges of the blank area 112 respectively, that is, the head insulating sublayer 310 and the tail insulating sublayer 320 do not completely cover the blank area 112, so as to ensure that the end of the battery cell formed by subsequent winding can conduct electricity, thereby ensuring the normal operation of the full-tab battery.

[0041] It should be noted that, for a wound-type battery cell, the electrode sheet 10 includes a positive electrode sheet and a negative electrode sheet. When the electrode sheet 10 is wound, the end ends of the positive electrode sheet and the negative electrode sheet are prone to misalignment, which increases the probability of contact between the positive electrode sheet and the negative electrode sheet, causing a greater safety hazard to the battery cell. Therefore, in the present disclosure, the head insulating sublayer 310 is arranged on the first side of the blank area 112 adjacent to the winding starting end 1111, so that the head insulating sublayer 310 is arranged adjacent to the winding starting end, and the tail insulating sublayer 320 is arranged on the second side of the blank area 112 adjacent to the winding ending end 1112, so that the tail insulating sublayer 320 is arranged adjacent to the winding ending end 1112. When the electrode sheet 10 is wound, the head insulating layer 310 is located inside the battery cell, and the tail insulating sub-layer 320 is located outside the battery cell. In this way, on the one hand, it can provide better support for the end of the battery cell to ensure that the battery cell will not be over-kneaded after the flattening operation. On the other hand, the added insulating layer 300 can also effectively prevent the battery cell from short-circuiting due to the misalignment of the end end of the positive electrode sheet and the end end of the negative electrode sheet after winding, thereby improving the safety of the full-ear battery; on the other hand, the added insulating layer 300 can also provide better protection for the winding starting end 1111 and the winding ending end 1112 of the first side 110 of the electrode substrate, effectively improving the phenomenon that the winding starting end 1111 and the winding ending end 1112 pierce the diaphragm due to burrs to cause local short circuit in the battery, thereby reducing the defective rate of the battery cell K value.

[0042] It is worth mentioning that in actual mass production, since the pole piece substrate 100 is coated and produced in a whole roll, the pole piece substrate 100 needs to be cut and split after coating and drying. If the head insulating sublayer 310 and the tail insulating sublayer 320 are not respectively provided at the winding starting end 1111 and the winding ending end 1112 of the pole piece substrate 100, it is easy to form more burrs during the cutting, resulting in the winding starting end 1111 and the winding ending end 1112 to easily pierce the diaphragm during winding, causing a local short circuit in the battery. Therefore, the present invention adds a head insulating sublayer 310 and a tail insulating sublayer 320 at the winding starting end 1111 and the winding ending end 1112, respectively, which can provide better protection for the winding starting end 1111 and the winding ending end 1112 of the first side 110 of the pole piece substrate, and effectively improve the phenomenon that the winding starting end 1111 and the winding ending end 1112 are pierced through the diaphragm by burrs to cause local short circuit in the battery.

[0043] like Figure 1 and Figure 3As shown, in one embodiment, the number of the head insulating sub-layers 310 is two, and the blank area 112 includes a first edge blank sub-area 1121 and a second edge blank sub-area 1122, and the first edge blank sub-area 1121 and the second edge blank sub-area 1122 are respectively located on both sides of the coating area 111; the two head insulating sub-layers 310 are respectively arranged on the first edge blank sub-area 1121 and the second edge blank sub-area 1122.

[0044] It can be understood that since the two head insulating sub-layers 310 are respectively arranged on the first edge blank sub-area 1121 and the second edge blank sub-area 1122, the two head insulating sub-layers 310 can be respectively arranged on both sides of the active conductive layer 200. In this way, on the one hand, the protection area of ​​the head insulating sub-layer 310 for the winding starting end 1111 is increased, and the phenomenon of the burrs piercing the diaphragm at the winding starting end 1111 to cause local short circuit of the battery is more effectively improved, and the defective rate of the K value of the battery cell is better reduced; on the other hand, it can play a better supporting role for the ends of the battery cell to better ensure that the two ends of the battery cell will not be over-kneaded after the flattening operation, and on the other hand, it can better ensure that the ends of the two ends of the battery cell after winding are not prone to short circuit, thereby better improving the safety of the full-ear battery.

[0045] Likewise, if Figure 1 As shown, in one of the embodiments, the number of the tail insulating sub-layers 320 is two, and the two tail insulating sub-layers 320 are respectively located on the first edge blank sub-area 1121 and the second edge blank sub-area 1122, so that, on the one hand, the two additional tail insulating sub-layers 320 increase the protection area of ​​the winding end 1112, and more effectively improve the phenomenon that the winding end 1112 pierces the diaphragm due to burrs to cause local short circuit of the battery, and better reduce the defective rate of the K value of the battery cell; on the other hand, it can play a better supporting role on the ends of the battery cell, so as to better ensure that the ends of the battery cell will not be over-kneaded after the flattening operation, and on the other hand, better ensure that the ends of the battery cell after winding are not prone to short circuit, thereby better improving the safety of the full-ear battery.

[0046] like Figure 1 and Figure 2 As shown, in one embodiment, the blank area 112 is extended along the length direction of the coating area 111 to ensure that the head insulating sublayer 310 and the tail insulating sublayer 320 are arranged with a long interval. In this way, the use of the insulating layer 300 can be minimized while ensuring that the thickness of the battery cell end is thin, which is conducive to the development of lightweight lithium batteries and reduces costs. It also improves the phenomenon that the burrs pierce the diaphragm at the starting end 1111 and the ending end 1112 of the winding to cause local short circuits in the battery.

[0047] Specifically, Figure 2 and Figure 3 As shown, in one embodiment, the first edge blank sub-area 1121 and the second edge blank sub-area 1122 are extended along the length direction of the coating area 111 to ensure that the two end insulating sub-layers can be arranged with long intervals in the first edge blank sub-area 1121, and the two tail insulating sub-layers 320 can be arranged with long intervals in the second edge blank sub-area 1122.

[0048] like Figure 3 and Figure 4 As shown, in one embodiment, one end of the head insulating sublayer 310 is in contact with the active conductive layer 200, so that there is no gap in the connection between the head insulating sublayer 310 and the active conductive layer 200, so as to ensure that the width distribution area of ​​the head insulating sublayer 310 in the blank area 112 is large, thereby preventing burrs from piercing the first surface 110 of the pole piece substrate during winding to the greatest extent, causing the battery cell to be prone to local short circuit during long-term use.

[0049] Similarly, the tail insulating sublayer 320 also has a similar structure. For example, in one embodiment, one end of the tail insulating sublayer 320 abuts against the active conductive layer 200 to prevent burrs from piercing the first surface 110 of the pole piece substrate during winding to the greatest extent, thereby causing the battery cell to be prone to local short circuit during long-term use.

[0050] In one embodiment, the insulating layer 300 is a ceramic insulating layer 300. It can be understood that, since the ceramic insulating layer 300 has good support, it is ensured that the additional ceramic insulating layer 300 can play a good supporting role on the inside and outside of the end of the battery cell, and more effectively avoid the phenomenon that the battery cell is prone to over-kneading during the flattening operation. At the same time, the ceramic insulating layer 300 also has good heat dissipation performance, so as to ensure that the ceramic insulating layer 300 at the end can quickly dissipate the heat inside the battery cell, thereby improving the heat dissipation performance of the battery cell, especially with the use of one end of the head insulating sublayer 310 abutting against the active conductive layer 200 and one end of the tail insulating sublayer 320 abutting against the active conductive layer 200, so as to better achieve heat dissipation inside the battery cell.

[0051] In one embodiment, the thickness of the head insulating sublayer 310 is 5um~50um, the width is 2mm~4mm and the length is 220mm~260mm, so as to ensure that the distribution of the head insulating sublayer 310 in the blank area 112 is more appropriate, especially in conjunction with the use of the tail insulating sublayer 320 with a thickness of 5um~50um, a width of 2mm~4mm and a length of 220mm~260mm, so as to ensure that the distribution of the head insulating sublayer 310 and the tail insulating sublayer 320 in the blank area 112 is more appropriate. In this way, while reducing the usage of the insulating layer 300, it can also provide better support for the ends of the battery cell, effectively avoiding the phenomenon of over-kneading of the battery cell, and effectively improving the phenomenon of local short circuit of the battery caused by burrs piercing the diaphragm at the starting end 1111 and the ending end 1112 of the winding, thereby improving the safety of the full-ear battery and reducing the defective rate of the battery cell K value.

[0052] In one of the embodiments, the distance between the head insulating sublayer 310 and the tail insulating sublayer 320 is 1980 mm to 2340 mm, so as to achieve a long interval arrangement of the head insulating sublayer and the tail insulating sublayer 320 .

[0053] In one embodiment, the height difference between the head insulating sublayer 310 and the blank area 112 is 7mm to 8mm, so as to ensure that the gap formed by the head insulating sublayer 310 and the edge of the blank area 112 is more appropriate. Similarly, in other embodiments, the height difference between the tail insulating sublayer 320 and the blank area 112 is 7mm to 8mm, so as to ensure that the gap formed by the tail insulating sublayer 320 and the edge of the blank area 112 is more appropriate, so as to ensure that the end of the battery cell formed by subsequent winding can conduct electricity, thereby ensuring the normal operation of the battery.

[0054] like Figure 2 and Figure 3 As shown, in one embodiment, the number of the active conductive layer 200 is multiple. It can be understood that multiple active conductive layers 200 are stacked in sequence to set the coating area 111 to ensure that a high-energy battery cell is prepared. Specifically, the number can be two, three, four or more, and those skilled in the art can select according to actual production needs.

[0055] In order to prepare high energy batteries, Figures 2 to 4As shown, in one embodiment, the second side 120 of the pole piece substrate is provided with the coating area 111, the blank area 112, the active conductive layer 200 and the insulating layer 300. It can be understood that by also providing the coating area 111, the blank area 112, the active conductive layer 200 and the insulating layer 300 on the second side 120 of the pole piece substrate, the second side 120 of the pole piece substrate also has the structure of the first side. In this way, while improving the energy density of the electrode sheet 10, the use amount of the insulating layer 300 is also reduced, and the end of the battery cell can be better supported, effectively avoiding the phenomenon that the battery cell is prone to over-kneading, and improving the safety of the full-ear battery, and reducing the defective rate of the battery cell K value.

[0056] The present disclosure also provides a battery cell, including a positive electrode sheet and a negative electrode sheet, wherein the positive electrode sheet and / or the negative electrode sheet adopts the electrode sheet 10 described in any of the above embodiments. It can be understood that since the battery cell includes a positive electrode sheet, a negative electrode sheet and a separator, the user can select the positive electrode sheet to adopt the structure of the electrode sheet 10 disclosed in the present disclosure, or the negative electrode sheet to adopt the structure of the electrode sheet 10 disclosed in the present disclosure, or the positive / negative electrode sheet to adopt the structure of the electrode sheet 10 disclosed in the present disclosure according to actual production needs. In this way, not only the use amount of the insulating layer 300 at the end of the battery cell is effectively reduced, but also the end of the battery cell can be better supported, effectively avoiding the phenomenon that the battery cell is prone to over-kneading, and effectively improving the phenomenon that the burrs pierce the separator at the winding start end 1111 and the winding end end 1112 to cause a local short circuit in the battery, thereby improving the safety of the full-ear battery and reducing the defective rate of the battery cell K value.

[0057] In one embodiment, when the active conductive layer 200 of the electrode sheet 10 is a positive active conductive layer 200, it can be made into a positive electrode sheet, and when the active conductive layer 200 of the electrode sheet 10 is a negative active conductive layer 200, it can be made into a negative electrode sheet.

[0058] In one of the embodiments, the positive electrode sheet adopts the electrode sheet 10 structure disclosed in the present invention, and the sum of the heights of the positive electrode sheet insulating layer 300 and the positive electrode active conductive layer 200 is controlled to be higher than the height of the negative electrode active conductive layer 200 of the negative electrode sheet, so as to ensure that the insulating layer 300 added to the positive electrode sheet can have a good insulating effect on the negative electrode sheet after the winding operation, thereby improving the safety of the battery cell.

[0059] The present disclosure also provides a full-tab battery, including the battery cell described in any of the above embodiments. It can be understood that since the flattened density of the end of the full-tab battery is relatively high, by adding an insulating layer 300 at the end of the battery cell, on the one hand, the phenomenon of excessive flattened density at the end of the full-tab battery can be improved, and on the other hand, the added insulating layer 300 can also play a good supporting role at the end of the full-tab battery, effectively avoiding the phenomenon of over-kneading of the battery cell, and on the other hand, it can also improve the heat dissipation and safety of the full-tab battery.

[0060] Compared with the prior art, the utility model has at least the following advantages:

[0061] 1) Since the head insulating sublayer 310 and the tail insulating sublayer 320 are arranged at intervals on the blank area 112, a gap can be formed between the head insulating sublayer 310 and the tail insulating sublayer 320, thereby reducing the use of the insulating layer 300 in the middle of the blank area 112. In this way, it is ensured that the overall weight of the battery cell will not change significantly, which is conducive to the development of lightweight lithium batteries and reduces production costs. It also ensures that the thickness of the end of the battery cell is thinner, which is more conducive to the flattening operation of the full-tab battery. Since the height of the head insulating sublayer 310 and the tail insulating sublayer 320 are both less than the height of the blank area 112, gaps are formed between the head insulating sublayer 310 and the tail insulating sublayer 320 and the edges of the blank area 112, that is, the head insulating sublayer 310 and the tail insulating sublayer 320 do not completely cover the blank area 112, so as to ensure that the end of the battery cell formed by subsequent winding can be conductive, thereby ensuring the normal operation of the full-tab battery.

[0062] 2) Since the head insulating sublayer 310 is arranged on the first side of the blank area 112 adjacent to the winding starting end 1111, the head insulating sublayer 310 is arranged adjacent to the winding starting end, and the tail insulating sublayer 320 is arranged on the second side of the blank area 112 adjacent to the winding ending end 1112, the tail insulating sublayer 320 is arranged adjacent to the winding ending end 1112. When the electrode sheet 10 is wound, the head insulating sublayer 310 is located inside the battery cell, and the tail insulating sublayer 320 is located outside the battery cell. In this way, on the one hand, it can provide a better support for the end of the battery cell, ensuring The battery cell will not be over-kneaded after the flattening operation. On the other hand, the added insulating layer 300 can effectively prevent the battery cell from short-circuiting due to the misalignment of the end end of the positive electrode sheet and the end end of the negative electrode sheet after winding, thereby improving the safety of the full-ear battery; on the other hand, the added insulating layer 300 can also provide better protection for the winding starting end 1111 and the winding ending end 1112 of the first side 110 of the electrode substrate, effectively improving the phenomenon of local short circuit of the battery caused by burrs piercing the diaphragm at the winding starting end 1111 and the winding ending end 1112, thereby reducing the defective rate of the battery cell K value.

[0063] The above-mentioned embodiments only express several implementation methods of the utility model, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the utility model patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the utility model, which all belong to the protection scope of the utility model. Therefore, the protection scope of the utility model patent shall be based on the attached claims.

Claims

1. An electrode sheet, comprising an electrode sheet substrate, an active conductive layer and an insulating layer, wherein the first surface of the electrode sheet substrate comprises a coating area and a blank area, and the active conductive layer is disposed on the coating area, characterized in that: The coating area has a winding start end and a winding end end; The insulating layer includes a head insulating sublayer and a tail insulating sublayer, and the head insulating sublayer and the tail insulating sublayer are spaced apart on the blank area. The head insulating sublayer is located on a first side of the blank area adjacent to the starting end of the winding, and the tail insulating sublayer is located on a second side of the blank area adjacent to the ending end of the winding, and the heights of the head insulating sublayer and the tail insulating sublayer are both smaller than the height of the blank area.

2. The electrode sheet according to claim 1, characterized in that: The number of the head insulating sub-layers is two, and the blank area includes a first edge blank sub-area and a second edge blank sub-area, and the first edge blank sub-area and the second edge blank sub-area are respectively located on both sides of the coating area; the two head insulating sub-layers are respectively arranged on the first edge blank sub-area and the second edge blank sub-area.

3. The electrode sheet according to claim 2, characterized in that: The number of the tail insulating sub-layers is two, and the two tail insulating sub-layers are respectively located on the first edge blank sub-region and the second edge blank sub-region correspondingly.

4. The electrode sheet according to claim 1, characterized in that: One end of the head insulating sublayer abuts against the active conductive layer.

5. The electrode sheet according to claim 1, characterized in that: One end of the tail insulating sublayer abuts against the active conductive layer.

6. The electrode sheet according to claim 1, characterized in that: The insulating layer is a ceramic insulating layer.

7. The electrode sheet according to claim 6, characterized in that: The thickness of the head insulating layer is 5um to 50um, the width is 2mm to 4mm and the length is 220mm to 260mm; and / or, The tail insulating sublayer has a thickness of 5um to 50um, a width of 2mm to 4mm and a length of 220mm to 260mm.

8. The electrode sheet according to claim 7, characterized in that: The distance between the head insulating sublayer and the tail insulating sublayer is 1980 mm to 2340 mm; and / or, The height difference between the head insulating sublayer and the blank area is 7 mm to 8 mm; and / or, The height difference between the tail insulating sublayer and the blank area is 7 mm to 8 mm; and / or, The blank area is extended along the length direction of the coating area; and / or, The number of the active conductive layers is multiple; and / or, The second surface of the pole piece substrate is provided with the coating area, the blank area, the active conductive layer and the insulating layer.

9. A battery cell, comprising a positive electrode sheet and a negative electrode sheet, characterized in that: The positive electrode sheet and / or the negative electrode sheet adopts the electrode sheet according to any one of claims 1 to 8.

10. A full-tab battery, characterized in that: Comprising the battery cell as claimed in claim 9.

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