Battery cell, battery and electronic equipment

Abstract

The utility model discloses a battery cell, battery and electronic equipment, the battery cell includes: a main body including a positive pole piece and a negative pole piece, the main body is formed by winding after the positive pole piece and the negative pole piece are laminated; the first positive tab is electrically connected to the positive plate; the second positive tab is electrically connected to the positive plate; the negative tab is electrically connected to the negative plate; wherein the first positive tab and the negative tab are respectively positioned on two sides of the width direction of the second positive tab; the main body is provided with a first thinned area, a second thinned area and a third thinned area, in the thickness direction of the main body, the projection of the first positive tab falls within the projection range of the first thinned area, the projection of the second positive tab falls within the projection range of the second thinned area, and the projection of the third thinned area falls within the projection range of the third thinned area. And the projection of the negative tab falls within the projection range of the third thinning area. The battery cell disclosed by the utility model can have relatively high energy density.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, in particular to a battery cell, a battery and an electronic device. Background Art

[0002] In the related art, the battery cell includes a positive electrode sheet, a negative electrode sheet and a separator. The positive electrode sheet is usually made of an active material with a high energy density (such as lithium cobalt oxide, nickel cobalt manganese ternary material or lithium iron phosphate) coated on a conductive current collector (such as aluminum foil). It is responsible for storing lithium ions during the charging process and releasing these ions to generate electrical energy during discharge. The negative electrode sheet mostly uses graphite or silicon-carbon composite materials as the active material, and is also coated on a current collector such as copper foil. It receives lithium ions migrated from the positive electrode during charging and releases them back to the positive electrode during discharge, completing the conversion between electrical energy and chemical energy. The separator mainly allows ions in the electrolyte to shuttle freely to maintain the smooth circuit and prevent short circuits between the positive and negative electrodes.

[0003] Furthermore, in order to increase the charging speed of the battery cell, a plurality of tabs are usually provided on the battery cell. However, after the plurality of tabs are provided, the tabs will occupy space in the thickness direction of the battery cell, resulting in a lower energy density of the battery cell. Utility Model Content

[0004] The present invention aims to solve at least one of the technical problems in the prior art. To this end, the present invention provides a battery cell having a high energy density.

[0005] The utility model also provides a battery.

[0006] The utility model also provides an electronic device.

[0007] The battery cell according to the first embodiment of the present invention includes:

[0008] A main body, comprising a positive electrode sheet and a negative electrode sheet, wherein the main body is formed by stacking the positive electrode sheet and the negative electrode sheet and then winding them;

[0009] a first positive electrode tab, electrically connected to the positive electrode sheet;

[0010] a second positive electrode tab, electrically connected to the positive electrode sheet;

[0011] a negative electrode tab, electrically connected to the negative electrode sheet;

[0012] In which, the first positive electrode ear and the negative electrode ear are respectively located on both sides of the width direction of the second positive electrode ear; the main body is provided with a first thinning area, a second thinning area and a third thinning area, and along the thickness direction of the main body, the projection of the first positive electrode ear falls within the projection range of the first thinning area, the projection of the second positive electrode ear falls within the projection range of the second thinning area, and the projection of the negative electrode ear falls within the projection range of the third thinning area.

[0013] The battery cell according to the embodiment of the present invention has at least the following beneficial effects: along the thickness direction of the main body, the projection of the first positive electrode ear falls within the projection range of the first thinned area, the projection of the second positive electrode ear falls within the projection range of the second thinned area, and the projection of the negative electrode ear falls within the projection range of the third thinned area. In the prior art, after the main body has multiple tabs, there is no thinned area on the main body. Therefore, multiple tabs will lead to a low energy density of the battery cell. In the present application, the first thinned area can provide a space for the first positive electrode ear to accommodate, thereby effectively avoiding the first positive electrode ear from occupying too much in the thickness direction of the main body. Similarly, the second thinned area can provide a space for the second positive electrode ear to accommodate, thereby effectively avoiding the second positive electrode ear from occupying too much in the thickness direction of the main body. The third thinned area can provide a space for the negative electrode ear to accommodate, thereby effectively avoiding the negative electrode ear from occupying too much in the thickness direction of the main body. In this way, the energy density of the battery cell of the present application is relatively high. Specifically, the battery cell can have a relatively high energy density.

[0014] According to the battery cell of some embodiments of the present invention, the first thinned area, the second thinned area and the third thinned area are all arranged on the positive electrode sheet.

[0015] In the battery cell according to some embodiments of the present invention, the first thinned region is connected to the second thinned region.

[0016] According to the battery cell of some embodiments of the present invention, two ends of the second thinned region are respectively connected to the first thinned region and the third thinned region.

[0017] According to some embodiments of the battery cell of the present invention, the first thinned area, the second thinned area and the third thinned area are all arranged on the negative electrode sheet, and the positive electrode sheet corresponding to the first thinned area, the second thinned area and the third thinned area is provided with an insulating layer

[0018] According to some embodiments of the battery cell of the present invention, the first thinned area and the second thinned area are both arranged on the positive electrode sheet, the third thinned area is arranged on the negative electrode sheet, and an insulating layer is provided on the positive electrode sheet corresponding to the third thinned area.

[0019] According to some embodiments of the present invention, the battery cell further comprises two positive electrode tab glues, and the two positive electrode tab glues are respectively attached to the first positive electrode tab and the second positive electrode tab.

[0020] According to the battery cell of some embodiments of the present invention, the shoulder width of the positive electrode tab glue in the width direction of the main body is M, and 2mm≤M≤3mm.

[0021] According to some embodiments of the battery cell of the present invention, along the width direction of the main body, the distance between the first positive electrode tab and the second positive electrode tab is L1, and L1 ≥ 2M.

[0022] According to some embodiments of the battery cell of the present invention, along the width direction of the main body, the distance between the first positive electrode tab and the negative electrode tab is L2, and L2-L1≥2M.

[0023] According to some embodiments of the present invention, the battery cell further includes a separator, and the separator is located between the positive electrode sheet and the negative electrode sheet.

[0024] A battery according to an embodiment of the second aspect of the present invention includes:

[0025] a housing having a storage cavity;

[0026] The battery cell according to any one of the embodiments of the first aspect is arranged in the storage cavity.

[0027] According to the battery of the embodiment of the present invention, there are at least the following beneficial effects: along the thickness direction of the main body, the projection of the first positive electrode ear falls within the projection range of the first thinned area, the projection of the second positive electrode ear falls within the projection range of the second thinned area, and the projection of the negative electrode ear falls within the projection range of the third thinned area. In the prior art, after the main body has multiple tabs, there is no thinned area on the main body. Therefore, multiple tabs will lead to a low energy density of the battery cell. In the present application, the first thinned area can provide a space for the first positive electrode ear to accommodate, thereby effectively avoiding the first positive electrode ear from occupying too much in the thickness direction of the main body. Similarly, the second thinned area can provide a space for the second positive electrode ear to accommodate, thereby effectively avoiding the second positive electrode ear from occupying too much in the thickness direction of the main body. The third thinned area can provide a space for the negative electrode ear to accommodate, thereby effectively avoiding the negative electrode ear from occupying too much in the thickness direction of the main body. In this way, the energy density of the battery cell of the present application is high. Specifically, the battery cell can have a high energy density. Furthermore, the energy density of the battery cell with this battery cell is high.

[0028] An electronic device according to an embodiment of the third aspect of the present invention includes the battery described in the embodiment of the second aspect.

[0029] The electronic device according to the embodiment of the present invention has at least the following beneficial effects: along the thickness direction of the main body, the projection of the first positive tab falls within the projection range of the first thinned area, the projection of the second positive tab falls within the projection range of the second thinned area, and the projection of the negative tab falls within the projection range of the third thinned area. In the prior art, after the main body has multiple tabs, there is no thinned area on the main body. Therefore, the multiple tabs will lead to a low energy density of the battery cell. In the present application, the first thinned area can provide a space for the first positive tab to be accommodated, thereby effectively preventing the first positive tab from occupying too much of the thickness direction of the main body. Similarly, the second thinned area can provide a space for the second positive tab to be accommodated, thereby effectively preventing the second positive tab from occupying too much of the thickness direction of the main body. The third thinned area can provide a space for the negative tab to be accommodated, thereby effectively preventing the negative tab from occupying too much of the thickness direction of the main body. As a result, the energy density of the battery cell of the present application is high. Specifically, the battery cell can have a high energy density. Furthermore, the energy density of the battery cell is high. Furthermore, the electronic device with the battery has a good battery life.

[0030] Additional aspects and advantages of the present invention will be given in part in the following description and will become apparent from the following description or learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The present invention will be further described below with reference to the accompanying drawings and embodiments, wherein:

[0032] Figure 1 A schematic diagram of a battery cell according to a first embodiment of the present invention;

[0033] Figure 2 A schematic diagram of a battery cell according to a second embodiment of the present invention;

[0034] Figure 3 is a schematic diagram of a battery cell according to a third embodiment of the present invention;

[0035] Figure 4 is a schematic diagram of a battery cell according to a fourth embodiment of the present invention;

[0036] Figure 5 is a schematic diagram of a battery cell according to a fifth embodiment of the present invention;

[0037] Figure 6 FIG. 1 is a schematic diagram of a battery cell according to a sixth embodiment of the present invention.

[0038] Reference numerals:

[0039] Battery cell 10, main body 100, first thinned area 110, second thinned area 120, third thinned area 130, positive electrode sheet 200, negative electrode sheet 300, separator 400, first positive electrode tab 500, second positive electrode tab 600, negative electrode tab 700, positive electrode tab glue 800, negative electrode tab glue 900, insulating layer 1000. DETAILED DESCRIPTION

[0040] The following describes embodiments of the present invention in detail. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended only to explain the present invention and are not to be construed as limiting the present invention.

[0041] In the description of the present invention, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on the present invention.

[0042] In the description of this utility model, "several" means more than one, "plurality" means more than two, "greater than," "less than," and "exceed" are understood to exclude the number itself, while "above," "below," and "within" are understood to include the number itself. The use of the terms "first" and "second" is solely for the purpose of distinguishing technical features and is not to be construed as indicating or implying relative importance, implicitly specifying the number of the indicated technical features, or implicitly specifying the order of the indicated technical features.

[0043] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, and connecting should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0044] In the description of the present invention, reference to terms such as "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the exemplary expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0045] In the related art, the battery cell 10 includes a positive electrode sheet 200, a negative electrode sheet 300 and a separator 400. The positive electrode sheet 200 is usually made of an active material with a high energy density (such as lithium cobalt oxide, nickel-cobalt-manganese ternary material or lithium iron phosphate) coated on a conductive current collector (such as aluminum foil). It is responsible for storing lithium ions during the charging process and releasing these ions to generate electrical energy during discharge. The negative electrode sheet 300 often uses graphite or silicon-carbon composite materials as the active material and is also coated on a current collector such as copper foil. It receives lithium ions migrated from the positive electrode during charging and releases them back to the positive electrode during discharge, completing the conversion between electrical energy and chemical energy. The separator 400 mainly allows ions in the electrolyte to shuttle freely to maintain the smooth circuit and prevents short circuits between the positive electrode sheet 200 and the negative electrode sheet 300.

[0046] Furthermore, to increase the charging speed of the battery cell 10, multiple tabs are typically provided on the battery cell 10. However, these tabs occupy space in the thickness direction of the battery cell 10, resulting in a lower energy density of the battery cell 10. For example, the battery cell 10 may be provided with two positive tabs, wherein the positive tabs are connected to the current collector of the positive electrode sheet 200. The thickness of the positive tabs may be greater than the thickness of the active material layer on the positive electrode sheet 200, so that the positive tabs protrude relative to the positive electrode sheet 200. This increases the thickness of the battery cell 10 and reduces the energy density of the battery cell 10. To this end, the present application proposes a battery cell 10.

[0047] Please refer to Figures 1 to 6In some embodiments, the battery cell 10 includes: a main body 100, a first positive electrode tab 500, a second positive electrode tab 600, and a negative electrode tab 700. The main body 100 includes a positive electrode sheet 200 and a negative electrode sheet 300, and the main body 100 is formed by stacking the positive electrode sheet 200 and the negative electrode sheet 300 and then winding them. Specifically, the positive electrode sheet 200 is usually made of an active material with a high energy density coated on a conductive current collector, such as lithium cobalt oxide, nickel cobalt manganese ternary material or lithium iron phosphate, and the conductive current collector can be, for example, aluminum foil. The negative electrode sheet 300 is mostly made of graphite or silicon-carbon composite materials as the active material, and is coated on a current collector such as copper foil. Among them, after the positive electrode sheet 200 and the negative electrode sheet 300 are stacked in the thickness direction of the positive electrode sheet 200, the same end of the positive electrode sheet 200 and the negative electrode sheet 300 are wound to form the main body 100. The tabs include a positive tab and a negative tab 700. During charging, an external power source inputs electrical energy into the battery cell 10 through the positive tab, causing lithium ions to be released from the positive electrode material and migrate to the negative electrode through the electrolyte. During discharge, lithium ions are released from the negative electrode material, return to the positive electrode through the electrolyte, and release electrical energy. This process also requires the positive tabs to transmit electrical energy to the external circuit. In the application, the positive tabs include a first positive tab 500 and a second positive tab 600. The first positive tab 500 is electrically connected to the positive electrode sheet 200, and the second positive tab 600 is electrically connected to the positive electrode sheet 200. The number of first positive tabs 500 and second positive tabs 600 is not specifically limited. For example, the number of first positive tabs 500 can be one, two, or more, and the number of second positive tabs 600 can be one, two, or more. The electrical connection of the first positive tab 500 to the positive electrode sheet 200 can specifically be achieved by welding the first positive tab 500 to the positive electrode sheet 200. The second positive electrode tab 600 is electrically connected to the positive electrode sheet 200 by, for example, welding the second positive electrode tab 600 to the positive electrode sheet 200. The negative electrode tab 700 is electrically connected to the negative electrode sheet 300, and the number of negative electrode tabs 700 can be one. The negative electrode tab 700 is electrically connected to the negative electrode sheet 300 by, for example, welding the negative electrode tab 700 to the negative electrode sheet 300. The first positive electrode tab 500 and the negative electrode tab 700 are respectively located on either side of the second positive electrode tab 600 in the width direction.

[0048] Please refer to Figures 1 to 6The main body 100 is provided with a first thinned area 110, a second thinned area 120, and a third thinned area 130. The first thinned area 110 can be formed by providing a groove in the active material layer of the positive electrode sheet 200, or the first thinned area 110 can be formed by providing a groove in the active material layer of the negative electrode sheet 300, or the first thinned area 110 can be formed by removing the active material on the positive electrode sheet 200, or the first thinned area 110 can be formed by removing the active material on the negative electrode sheet 300. The second thinned area 120 can be formed by providing a groove in the active material layer of the positive electrode sheet 200, or the second thinned area 120 can be formed by providing a groove in the active material layer of the negative electrode sheet 300, or the second thinned area 120 can be formed by removing the active material on the positive electrode sheet 200, or the second thinned area 120 can be formed by removing the active material on the negative electrode sheet 300. The third thinned region 130 can be formed by providing a groove in the active material layer of the positive electrode sheet 200, or by providing a groove in the active material layer of the negative electrode sheet 300, or by removing the active material from the positive electrode sheet 200, or by removing the active material from the negative electrode sheet 300. Along the thickness direction of the body 100, the projection of the first positive electrode tab 500 falls within the projection range of the first thinned region 110. "The projection of the first positive electrode tab 500 falls within the projection range of the first thinned region 110" specifically means that the width and length of the first positive electrode tab 500 are equal to the width and length of the first thinned region 110, or the width and length of the first positive electrode tab 500 are less than the width and length of the first thinned region 110. That is, in the thickness direction of the body 100, the first positive tab 500 corresponds to the first thinned region 110, so that the protruding dimension of the first positive tab 500 is compensated by the first thinned region 110. For example, the protruding dimension of the first positive tab 500 from the positive electrode sheet 200 can be 1 mm, and the depth of the first thinned region 110 can be 1 mm or 2 mm. In this case, the problem of the first positive tab 500 causing the battery cell 10 to have a low energy density can be effectively avoided. The projection of the second positive tab 600 falls within the projection range of the second thinned region 120. Specifically, the projection of the second positive tab 600 falls within the projection range of the second thinned region 120 means that the width and length of the second positive tab 600 are equal to the width and length of the second thinned region 120, or the width and length of the second positive tab 600 are less than the width and length of the second thinned region 120.That is, in the thickness direction of the body 100, the second positive electrode tab 600 corresponds to the second thinned region 120, so that the protruding dimension of the second positive electrode tab 600 is compensated by the second thinned region 120. For example, the protruding dimension of the second positive electrode tab 600 from the positive electrode sheet 200 can be 1 mm, and the depth of the second thinned region 120 can be 1 mm or 2 mm. In this case, the problem of the second positive electrode tab 600 causing the battery cell 10 to have a low energy density can be effectively avoided. The projection of the negative electrode tab 700 falls within the projection range of the third thinned region 130. Specifically, the projection of the negative electrode tab 700 falling within the projection range of the third thinned region 130 means that the width and length of the negative electrode tab 700 are equal to the width and length of the third thinned region 130, or the width and length of the negative electrode tab 700 are less than the width and length of the third thinned region 130. That is, in the thickness direction of the main body 100, the negative and positive electrode tabs correspond to the third thinning zone 130, so that the protruding size of the negative electrode tab 700 is compensated by the third thinning zone 130. For example, the protruding size of the negative electrode tab 700 from the negative electrode sheet 300 can be 1 mm, and the depth of the third thinning zone 130 can be 1 mm or 2 mm. In this case, the problem of low energy density of the battery cell 10 caused by the negative electrode tab 700 can be effectively avoided. Specifically, along the thickness direction of the main body 100, the projection of the first positive electrode tab 500 falls within the projection range of the first thinning zone 110, the projection of the second positive electrode tab 600 falls within the projection range of the second thinning zone 120, and the projection of the negative electrode tab 700 falls within the projection range of the third thinning zone 130. In the prior art, after the main body 100 has multiple tabs, there is no thinning zone on the main body 100. Therefore, multiple tabs will lead to a lower energy density of the battery cell 10. In the present application, the first thinning zone 110 can provide the first positive electrode tab 500 with The first positive electrode tab 500 can be accommodated in a space, thereby effectively preventing the first positive electrode tab 500 from occupying too much of the thickness direction of the main body 100. Similarly, the second thinned area 120 can provide a space for accommodating the second positive electrode tab 600, thereby effectively preventing the second positive electrode tab 600 from occupying too much of the thickness direction of the main body 100. The third thinned area 130 can provide a space for accommodating the negative electrode tab 700, thereby effectively preventing the negative electrode tab 700 from occupying too much of the thickness direction of the main body 100. In this way, the energy density of the battery cell 10 of the present application is relatively high. Specifically, the battery cell 10 can have a relatively high energy density.

[0049] Further, the following describes a specific method in which the main body 100 is provided with the first thinning area 110, the second thinning area 120 and the third thinning area 130, please refer to Figures 1 to 4In some embodiments, the first thinned region 110, the second thinned region 120, and the third thinned region 130 are all disposed on the positive electrode sheet 200. Specifically, as mentioned above, the main body 100 is formed by stacking the positive electrode sheet 200 and the negative electrode sheet 300 and then winding them. Since the first thinned region 110, the second thinned region 120, and the third thinned region 130 can be formed by removing active material, after the first thinned region 110, the second thinned region 120, and the third thinned region 130 are all disposed on the positive electrode sheet 200, a portion of the active material of the positive electrode can be removed, which can effectively prevent the problem of lithium plating in the battery cell 10.

[0050] For further information, please refer to Figure 3 In some embodiments, the first thinned area 110 is connected to the second thinned area 120. Specifically, the first thinned area 110 is connected to the second thinned area 120, and the first thinned area 110 can be a groove, and the second thinned area 120 can be a groove, and the grooves are connected to each other. This method can reduce the number of processing times on the positive electrode sheet 200 (processing the first thinned area 110 and the second thinned area 120 at one time), thereby improving processing efficiency. In addition, please refer to Figure 4 In other embodiments, the ends of the second thinned area 120 are connected to the first thinned area 110 and the third thinned area 130, respectively. Specifically, the ends of the second thinned area 120 are connected to the first thinned area 110 and the third thinned area 130, respectively, which means that the first thinned area 110 can be a groove, the second thinned area 120 can be a groove, and the third thinned area 130 can be a groove, and the three grooves are interconnected, which can also reduce the number of processing times and improve processing efficiency. It is conceivable that in other embodiments, the second thinned area 120 is connected to the third thinned area 130.

[0051] Furthermore, if the first thinned area 110, the second thinned area 120 and the third thinned area 130 are all disposed on the positive electrode sheet 200, the amount of active material in the positive electrode sheet 200 may be small. Therefore, the first thinned area 110 and the second thinned area 120 may be disposed on the positive electrode sheet 200, and the third thinned area 130 may be disposed on the negative electrode sheet 300. For details, please refer to Figure 5In some embodiments, the first and second skived regions 110, 120 are both located on the positive electrode sheet 200, the third skived region 130 is located on the negative electrode sheet 300, and an insulating layer 1000 is provided on the positive electrode sheet 200 corresponding to the third skived region 130. The fact that the first and second skived regions 110, 120 are both located on the positive electrode sheet 200, and the third skived region 130 is located on the negative electrode sheet 300, can reduce the amount of active material on the positive electrode sheet 200 to less than that on the negative electrode sheet 300, effectively preventing lithium deposition in the battery cell 10. Furthermore, the insulating layer 1000 can inactivate the positive electrode active material corresponding to the third skived region 130, further effectively preventing lithium deposition in the battery cell 10.

[0052] Furthermore, in some embodiments, the first thinned region 110, the second thinned region 120, and the third thinned region 130 are all disposed on the negative electrode sheet 300, and an insulating layer 1000 is disposed on the positive electrode sheet 200 corresponding to the first thinned region 110, the second thinned region 120, and the third thinned region 130. Specifically, the insulating layer 1000 can inactivate the positive electrode active material corresponding to the first thinned region 110, the second thinned region 120, and the third thinned region 130, thereby further effectively preventing lithium deposition in the battery cell 10.

[0053] For further information, please refer to Figure 1 In some embodiments, the battery cell 10 further includes two positive electrode tab glues 800, which are respectively attached to the first positive electrode tab 500 and the second positive electrode tab 600. The primary function of the positive electrode tab glue 800 is insulation, preventing the tabs from directly contacting other parts of the battery (such as the aluminum-plastic film) and causing a short circuit. During the battery packaging process, the positive electrode tab glue 800 is heated and hot-melt-sealed to the aluminum-plastic film, forming an effective insulation barrier to ensure safe battery operation. In this way, after the two positive electrode tab glues 800 are respectively attached to the first positive electrode tab 500 and the second positive electrode tab 600, the safety of the battery can be improved. The battery cell 10 further includes a negative electrode tab glue 900, which is attached to the negative electrode tab 700.

[0054] For further information, please refer to Figure 1In some embodiments, the shoulder width of the positive electrode ear glue 800 in the width direction of the main body 100 is M, 2mm≤M≤3mm. The shoulder width of the positive electrode ear glue 800 refers to the portion of the positive electrode ear glue 800 that protrudes relative to the ear. The shoulder width of the positive electrode ear glue 800 in the width direction of the main body 100 may be 2mm, 2.5mm or 3mm. When the shoulder width of the positive electrode ear glue 800 in the width direction of the main body 100 is less than 2mm, due to the small size of the positive electrode ear glue 800, this may cause the insulation of the positive electrode ear glue 800 to be poor. When the shoulder width of the positive electrode ear glue 800 in the width direction of the main body 100 is greater than 3mm, on the premise that the positive electrode ear glue 800 meets the insulation performance, the excessive size will lead to waste of material.

[0055] For further information, please refer to Figures 1 to 6 In some embodiments, along the width direction of the main body 100, the distance between the first positive tab 500 and the second positive tab 600 is L1, L1 ≥ 7 mm, L1 ≥ 2M. Along the width direction of the main body 100, the distance between the first positive tab 500 and the second positive tab 600 can be 7 mm, 8 mm, or 9 mm, etc. When the distance between the first positive tab 500 and the second positive tab 600 is relatively close, the first positive tab 500 and the second positive tab 600 may overlap in the thickness direction of the main body 100, which increases the thickness of the battery cell 10, thereby reducing the energy density of the battery cell 10. In addition, when L1 is not less than 2M, the packaging effect of the battery cell 10 can be improved, thereby improving the reliability of the battery cell 10.

[0056] For further information, please refer to Figures 1 to 6 In some embodiments, along the width direction of the body 100, the distance between the first positive tab 500 and the negative tab 700 is L2, and L2-L1 ≥ 2M. If the distance between the second positive tab 600 and the negative tab 700 is too close, this may cause the second positive tab 600 and the negative tab 700 to contact, thereby causing a short circuit in the battery cell 10. When L2-L1 ≥ 2M is satisfied, the battery cell 10 has a good packaging effect and high reliability. For details, please refer to Table 1.

[0057] Table 1

[0058]

[0059] The test method involves dripping penetrant liquid onto the inside of the top seal of the battery cell 10, leaving it for 10 minutes, then cleaning it. The gel is then removed and inspected for any red traces. The table above shows that when L2-L1≥2M is met, the packaging of the battery cell 10 is excellent, achieving a 100% pass rate. However, when L2-L1≥2M is not met, the pass rate is lower.

[0060] For further information, please refer to Figures 1 to 6 In some embodiments, the battery cell 10 further includes a diaphragm 400, which is located between the positive electrode sheet 200 and the negative electrode sheet 300. Specifically, the main function of the diaphragm 400 is to prevent the positive electrode sheet 200 and the negative electrode sheet 300 from direct contact, thereby avoiding internal short circuit of the battery cell 10. At the same time, the diaphragm 400 can also allow electrolyte ions (such as lithium ions) to pass freely during the charging and discharging process to complete the storage and release of electrical energy. The diaphragm 400 has good insulation, ion permeability and certain mechanical strength. Specifically, the diaphragm 400 is usually made of microporous materials, such as polyethylene (PE), polypropylene (PP) or their composites. These materials have good insulation properties and can effectively prevent direct contact between the positive and negative poles of the battery. At the same time, their microporous structure allows electrolyte ions to pass through during the charging and discharging process to ensure the normal operation of the battery.

[0061] In some embodiments, the battery includes: a shell and the battery cell 10 in the above embodiment. The shell has a storage cavity. The shell can be an aluminum-plastic film or a metal shell, such as a steel shell or an aluminum shell. The battery cell 10 is arranged in the storage cavity. Specifically, along the thickness direction of the main body 100, the projection of the first positive electrode ear 500 falls within the projection range of the first thinning area 110, the projection of the second positive electrode ear 600 falls within the projection range of the second thinning area 120, and the projection of the negative electrode ear 700 falls within the projection range of the third thinning area 130. In the prior art, after the main body 100 has multiple pole ears, there is no thinning area on the main body 100. Therefore, multiple pole ears will cause the energy density of the battery cell 10 to be lower. In the present application, the first thinning area 110 can provide the first positive electrode ear 500 with The first positive electrode tab 500 is provided with a space for accommodation, thereby effectively preventing the first positive electrode tab 500 from occupying too much of the thickness direction of the main body 100. Similarly, the second thinned area 120 can provide a space for accommodation for the second positive electrode tab 600, thereby effectively preventing the second positive electrode tab 600 from occupying too much of the thickness direction of the main body 100. The third thinned area 130 can provide a space for accommodation for the negative electrode tab 700, thereby effectively preventing the negative electrode tab 700 from occupying too much of the thickness direction of the main body 100. In this way, the energy density of the battery cell 10 of the present application is relatively high. Specifically, the battery cell 10 can have a relatively high energy density. Furthermore, the battery having the battery cell 10 has a relatively high energy density.

[0062] In some embodiments, the electronic device includes the battery of the above embodiment. Specifically, along the thickness direction of the main body 100, the projection of the first positive electrode tab 500 falls within the projection range of the first thinned area 110, the projection of the second positive electrode tab 600 falls within the projection range of the second thinned area 120, and the projection of the negative electrode tab 700 falls within the projection range of the third thinned area 130. In the prior art, after the main body 100 has multiple tabs, there is no thinned area on the main body 100. Therefore, multiple tabs will lead to a lower energy density of the battery cell 10. In this application, the first thinned area 110 can provide the first positive electrode tab 500 with a thinned area. A space for accommodation, thereby effectively preventing the first positive electrode ear 500 from occupying too much of the dimension in the thickness direction of the main body 100. Similarly, the second thinned area 120 can provide a space for accommodation for the second positive electrode ear 600, thereby effectively preventing the second positive electrode ear 600 from occupying too much of the dimension in the thickness direction of the main body 100. The third thinned area 130 can provide a space for accommodation for the negative electrode ear 700, thereby effectively preventing the negative electrode ear 700 from occupying too much of the dimension in the thickness direction of the main body 100. In this way, the energy density of the battery cell 10 of the present application is relatively high. Specifically, the battery cell 10 can have a relatively high energy density. Furthermore, the energy density of the battery having the battery cell 10 is relatively high. Furthermore, the endurance of the electronic device having the battery is relatively good.

[0063] While the embodiments of the present invention have been described in detail above with reference to the accompanying drawings, the present invention is not limited to the embodiments described above. Various modifications may be made within the scope of knowledge possessed by a person skilled in the art without departing from the spirit of the present invention. Furthermore, the embodiments of the present invention and the features of the embodiments may be combined with each other unless there is a conflict.

Claims

1. A battery cell, characterized in that: include: A main body, comprising a positive electrode sheet and a negative electrode sheet, wherein the main body is formed by stacking the positive electrode sheet and the negative electrode sheet and then winding them; a first positive electrode tab, electrically connected to the positive electrode sheet; a second positive electrode tab, electrically connected to the positive electrode sheet; a negative electrode tab, electrically connected to the negative electrode sheet; In which, the first positive electrode ear and the negative electrode ear are respectively located on both sides of the width direction of the second positive electrode ear; the main body is provided with a first thinning area, a second thinning area and a third thinning area, and along the thickness direction of the main body, the projection of the first positive electrode ear falls within the projection range of the first thinning area, the projection of the second positive electrode ear falls within the projection range of the second thinning area, and the projection of the negative electrode ear falls within the projection range of the third thinning area.

2. The battery cell according to claim 1, characterized in that The first thinned area, the second thinned area and the third thinned area are all arranged on the positive electrode sheet.

3. The battery cell according to claim 2, characterized in that The first thinned region is connected to the second thinned region.

4. The battery cell according to claim 2, characterized in that Two ends of the second thinned region are respectively connected to the first thinned region and the third thinned region.

5. The battery cell according to claim 1, characterized in that The first thinned area, the second thinned area and the third thinned area are all arranged on the negative electrode sheet, and an insulating layer is provided on the positive electrode sheet corresponding to the first thinned area, the second thinned area and the third thinned area.

6. The battery cell according to claim 1, characterized in that The first thinned area and the second thinned area are both arranged on the positive electrode sheet, the third thinned area is arranged on the negative electrode sheet, and an insulating layer is provided on the positive electrode sheet corresponding to the third thinned area.

7. The battery cell according to claim 1, characterized in that The battery cell further includes two positive electrode tab glues, which are respectively attached to the first positive electrode tab and the second positive electrode tab.

8. The battery cell according to claim 7, characterized in that: The shoulder width of the positive electrode tab glue in the width direction of the main body is M, and 2mm≤M≤3mm.

9. The battery cell according to claim 8, characterized in that Along the width direction of the main body, the distance between the first positive electrode tab and the second positive electrode tab is L1, and L1 is greater than or equal to 2M.

10. The battery cell according to claim 9, characterized in that: Along the width direction of the main body, the distance between the first positive electrode tab and the negative electrode tab is L2, and L2-L1≥2M.

11. The battery cell according to claim 1, characterized in that The battery cell further includes a separator, which is located between the positive electrode sheet and the negative electrode sheet.

12. A battery, characterized in that include: a housing having a storage cavity; The battery cell according to any one of claims 1 to 11, arranged in the storage cavity.

13. An electronic device, characterized in that Comprising the battery of claim 12.

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