Battery cell, battery and electronic device

Abstract

Disclosed in the present application are a battery cell, a battery and an electronic device. The battery cell comprises: a body, comprising a positive electrode plate and a negative electrode plate, wherein the body is formed by stacking the positive electrode plate and the negative electrode plate and then winding same; a first positive tab electrically connected to the positive electrode plate; a second positive tab electrically connected to the positive electrode plate; and a negative tab electrically connected to the negative electrode plate. The first positive tab and the negative tab are respectively located on two sides of the second positive tab in the direction of width. The body is provided with a first thinned region, a second thinned region and a third thinned region. In the direction of thickness of the body, a projection of the first positive tab falls within a projection of the first thinned region, a projection of the second positive tab falls within a projection of the second thinned region, and a projection of the negative tab falls within a projection of the third thinned region. The battery cell of the present application can have a relatively high energy density.

Description

Battery cell, battery and electronic device TECHNICAL FIELD

[0001] The present application relates to the technical field of battery, in particular to a battery cell, a battery and an electronic device. BACKGROUND

[0002] In the related art, a 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 (such as lithium cobaltate, nickel cobalt manganese ternary material or iron lithium phosphate) with high energy density coated on a conductive current collector (such as aluminum foil), which is responsible for storing lithium ions during charging and releasing these ions to generate electric energy during discharging. The negative electrode sheet usually uses graphite or silicon-carbon composite material as an active material, which is also coated on a current collector such as copper foil, which receives lithium ions migrated from the positive electrode during charging and releases them back to the positive electrode during discharging, completing the conversion between electric energy and chemical energy. The separator mainly plays the role of allowing ions in the electrolyte to freely shuttle to maintain the smoothness of the circuit and prevent the short circuit of the positive electrode sheet and the negative electrode sheet.

[0003] Further, in order to improve 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 occupy the space in the thickness direction of the battery cell, resulting in a low energy density of the battery cell. SUMMARY

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

[0005] The present application also provides a battery.

[0006] The present application also provides an electronic device.

[0007] The battery cell according to the first aspect of the present application comprises:

[0008] a main body comprising a positive electrode sheet and a negative electrode sheet, the main body being formed by winding the positive electrode sheet and the negative electrode sheet after being stacked;

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

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

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

[0012] The first positive tab and the negative tab are respectively located on both sides of the width direction of the second positive tab; 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 tab falls within the projection range of the first thinning area, the projection of the second positive tab falls within the projection range of the second thinning area, and the projection of the negative tab falls within the projection range of the third thinning area.

[0013] The electric core according to the embodiments of the present application 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 thinning area, the projection of the second positive tab falls within the projection range of the second thinning area, and the projection of the negative tab falls within the projection range of the third thinning area; in the prior art, the main body has no thinning area after having multiple tabs, so the multiple tabs result in a low energy density of the electric core, while in the present application, the first thinning area can provide a containing space for the first positive tab, thereby effectively avoiding the first positive tab from occupying a size that is too large in the thickness direction of the main body; similarly, the second thinning area can provide a containing space for the second positive tab, thereby effectively avoiding the second positive tab from occupying a size that is too large in the thickness direction of the main body, and the third thinning area can provide a containing space for the negative tab, thereby effectively avoiding the negative tab from occupying a size that is too large in the thickness direction of the main body; in this way, the electric core has a high energy density. Specifically, the electric core can have a high energy density.

[0014] The first thinning area, the second thinning area and the third thinning area are all arranged on the positive tab.

[0015] The first thinning area is connected to the second thinning area.

[0016] The two ends of the second thinning area are respectively connected to the first thinning area and the third thinning area.

[0017] The first thinning area, the second thinning area and the third thinning area are all arranged on the negative tab, and the positive tab corresponding to the first thinning area, the second thinning area and the third thinning area is provided with an insulating layer.

[0018] The first thinning area and the second thinning area are arranged on the positive tab, and the third thinning area is arranged on the negative tab, and the positive tab corresponding to the third thinning area is provided with an insulating layer.

[0019] The battery cell according to some embodiments of the present application further comprises two positive tab adhesives, each of which is attached to the first positive tab and the second positive tab.

[0020] The battery cell according to some embodiments of the present application, the shoulder width of the positive tab adhesive is M, 2mm≤M≤3mm in the width direction of the main body.

[0021] The battery cell according to some embodiments of the present application, the distance between the first positive tab and the second positive tab is L1 in the width direction of the main body, L1≥2M.

[0022] The battery cell according to some embodiments of the present application, the distance between the first positive tab and the negative tab is L2 in the width direction of the main body, L2-L1≥2M.

[0023] The battery cell according to some embodiments of the present application further comprises a diaphragm between the positive sheet and the negative sheet.

[0024] The battery according to the second aspect of the embodiments of the present application comprises:

[0025] The shell has a storage cavity.

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

[0027] The battery according to the embodiments of the present application has at least the following beneficial effects: in the thickness direction of the main body, the projection of the first positive tab falls within the projection range of the first thinning area, the projection of the second positive tab falls within the projection range of the second thinning area, and the projection of the negative tab falls within the projection range of the third thinning area. In the prior art, the main body does not have a thinning area after having multiple tabs, so the multiple tabs result in a lower energy density of the battery cell. In the present application, the first thinning area can provide a space for the first positive tab, thereby effectively avoiding the first positive tab occupying too large a size in the thickness direction of the main body. Similarly, the second thinning area can provide a space for the second positive tab, thereby effectively avoiding the second positive tab occupying too large a size in the thickness direction of the main body. The third thinning area can provide a space for the negative tab, thereby effectively avoiding the negative tab occupying too large a size in the thickness direction of the main body. In this way, the battery cell of the present application has a higher energy density. Specifically, the battery cell can have a higher energy density. Further, the battery having the battery cell has a higher energy density.

[0028] The electronic device according to the third aspect of the embodiments of the present application comprises the battery according to the second aspect of the embodiments.

[0029] According to the electronic device provided in the embodiments of the present application, the following beneficial effects are achieved: the projection of the first positive tab falls within the projection range of the first thinning area, the projection of the second positive tab falls within the projection range of the second thinning area, and the projection of the negative tab falls within the projection range of the third thinning area. In the prior art, after the main body has multiple tabs, there is no thinning area on the main body. Therefore, the multiple tabs result in a low energy density of the battery cell. In the present application, the first thinning area can provide a space for the first positive tab, thereby effectively avoiding the first positive tab from occupying too large a size in the thickness direction of the main body. Similarly, the second thinning area can provide a space for the second positive tab, thereby effectively avoiding the second positive tab from occupying too large a size in the thickness direction of the main body. The third thinning area can provide a space for the negative tab, thereby effectively avoiding the negative tab from occupying too large a size in the thickness direction of the main body. In this way, the battery cell provided in the present application has a high energy density. Specifically, the battery cell can have a high energy density. Further, the battery provided with the battery cell has a high energy density. Still further, the electronic device provided with the battery has good endurance.

[0030] Additional aspects and advantages of the present application will be made apparent from the following description. BRIEF DESCRIPTION OF DRAWINGS

[0031] The present application will be further described below in conjunction with the accompanying drawings and embodiments, in which:

[0032] FIG. 1 is a schematic view of a battery cell according to a first embodiment of the present application;

[0033] FIG. 2 is a schematic view of a battery cell according to a second embodiment of the present application;

[0034] FIG. 3 is a schematic view of a battery cell according to a third embodiment of the present application;

[0035] FIG. 4 is a schematic view of a battery cell according to a fourth embodiment of the present application;

[0036] FIG. 5 is a schematic view of a battery cell according to a fifth embodiment of the present application;

[0037] FIG. 6 is a schematic view of a battery cell according to a sixth embodiment of the present application.

[0038] Reference signs: battery cell 10, main body 100, first thinning area 110, second thinning area 120, third thinning area 130, positive tab 200, negative tab 300, separator 400, first positive tab 500, second positive tab 600, negative tab 700, positive tab gasket 800, negative tab gasket 900, insulating layer 1000. DETAILED DESCRIPTION

[0039] Embodiments of the present application are described below in the accompanying drawings, in which like reference numerals refer to items of like functions in the various figures during the description. Embodiments described below are examples of the present application and are not intended to be limiting of the present application unless otherwise explicitly indicated herein.

[0040] In the description of the present application, if the orientation description, such as the upper, lower, front, back, left, right, and the like, is described, the orientation or position relationship shown in the drawings is based on the orientation or position relationship, which is only for the purpose of describing the present application and simplifying the description, and does not indicate or imply that the device or element indicated must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation of the present application.

[0041] In the description of the present application, if the meaning of several is more than one, the meaning of multiple is more than two, greater than, less than, more than, and the like are understood as not including the number, above, below, and the like are understood as including the number. If the first, second, and the like are described, they are only used for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features or the order of indicated technical features.

[0042] In the description of the present application, unless otherwise explicitly limited, the words such as setting, installing, connecting, and the like should be broadly understood, and the person skilled in the art can reasonably determine the specific meaning of the above words in the present application in combination with the specific content of the technical solution.

[0043] In the description of the present application, the description of the terms "one embodiment", "some embodiments", "exemplary embodiment", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in combination with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the exemplary description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0044] 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 (such as lithium cobaltate, nickel cobalt manganese ternary material, or iron lithium phosphate) with high energy density coated on a conductive current collector (such as an aluminum foil), which is responsible for storing lithium ions during charging and releasing these ions to generate electric energy during discharging. The negative electrode sheet 300 usually uses graphite or silicon-carbon composite material as the active material, which is also coated on a copper foil or other current collector. During charging, the negative electrode sheet 300 receives lithium ions migrated from the positive electrode, and during discharging, the negative electrode sheet 300 releases the lithium ions back to the positive electrode, completing the conversion between electric energy and chemical energy. The separator 400 mainly plays the role of allowing ions in the electrolyte to shuttle freely to maintain the smoothness of the circuit, and preventing the positive electrode sheet 200 and the negative electrode sheet 300 from short-circuiting.

[0045] Further, in order to improve the charging speed of the battery cell 10, usually a plurality of tabs are arranged on the battery cell 10. However, after arranging a plurality of tabs, the tabs will occupy the space in the thickness direction of the battery cell 10, resulting in a lower energy density of the battery cell 10. For example, two positive tabs are arranged on the battery cell 10, wherein the positive tabs are connected to the current collector of the positive electrode sheet 200. The thickness of the positive tab is greater than the thickness of the active material layer on the positive electrode sheet 200, so that the positive tab protrudes relative to the positive electrode sheet 200, which increases the thickness of the battery cell 10, thereby reducing the energy density of the battery cell 10. Therefore, the present application proposes a battery cell 10.

[0046] Referring to FIGS. 1-6, in some embodiments, the battery cell 10 includes a main body 100, a first positive tab 500, a second positive tab 600, and a negative tab 700. The main body 100 includes a positive sheet 200 and a negative sheet 300, and the main body 100 is formed by winding the positive sheet 200 and the negative sheet 300 after being stacked. Specifically, the positive sheet 200 is generally made of an active material with 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 an aluminum foil. The negative sheet 300 is generally made of graphite or silicon-carbon composite material as an active material, coated on a copper foil current collector. The positive sheet 200 and the negative sheet 300 are stacked in the thickness direction of the positive sheet 200, and then the same end of the positive sheet 200 and the negative sheet 300 is wound to form the main body 100. The tabs include the positive tabs and the negative tab 700. During charging, an external power source inputs electrical energy to the inside of the battery cell 10 through the positive tabs, causing lithium ions to be released from the positive material and migrate to the negative electrode through the electrolyte. During discharging, lithium ions are released from the negative material, travel back to the positive electrode through the electrolyte, and release electrical energy. This process also requires the electrical energy to be transmitted to the external circuit through the positive tabs. In the application, the positive tabs include the first positive tab 500 and the second positive tab 600. The first positive tab 500 is electrically connected to the positive sheet 200, and the second positive tab 600 is electrically connected to the positive sheet 200. The number of the first positive tab 500 and the second positive tab 600 is not specifically limited, such as one, two, or more first positive tabs 500, and one, two, or more second positive tabs 600. The first positive tab 500 can be electrically connected to the positive sheet 200 by being welded to the positive sheet 200. The second positive tab 600 can be electrically connected to the positive sheet 200 by being welded to the positive sheet 200. The negative tab 700 can be electrically connected to the negative sheet 300, and the number of the negative tab 700 can be one. The negative tab 700 can be electrically connected to the negative sheet 300 by being welded to the negative sheet 300. The first positive tab 500 and the negative tab 700 are respectively located on both sides of the second positive tab 600 in the width direction of the second positive tab 600.

[0047] Referring to FIGS. 1-6, the main body 100 is provided with a first thinning area 110, a second thinning area 120 and a third thinning area 130. The first thinning area 110 can be formed by providing a groove on the active material layer of the positive electrode sheet 200, or the first thinning area 110 can be formed by providing a groove on the active material layer of the negative electrode sheet 300, or the first thinning area 110 can be formed by removing the active material on the positive electrode sheet 200, or the first thinning area 110 can be formed by removing the active material on the negative electrode sheet 300. The second thinning area 120 can be formed by providing a groove on the active material layer of the positive electrode sheet 200, or the second thinning area 120 can be formed by providing a groove on the active material layer of the negative electrode sheet 300, or the second thinning area 120 can be formed by removing the active material on the positive electrode sheet 200, or the second thinning area 120 can be formed by removing the active material on the negative electrode sheet 300. The third thinning area 130 can be formed by providing a groove on the active material layer of the positive electrode sheet 200, or the third thinning area 130 can be formed by providing a groove on the active material layer of the negative electrode sheet 300, or the third thinning area 130 can be formed by removing the active material on the positive electrode sheet 200, or the third thinning area 130 can be formed by removing the active material on the negative electrode sheet 300. In the thickness direction of the main body 100, the projection of the first positive tab 500 falls within the projection range of the first thinning area 110, which specifically means that the width and length of the first positive tab 500 are equal to or less than the width and length of the first thinning area 110. That is, in the thickness direction of the main body 100, the first positive tab 500 corresponds to the first thinning area 110, so that the size of the first positive tab 500 protruding from the positive electrode sheet 200 is compensated by the first thinning area 110. For example, the size of the first positive tab 500 protruding from the positive electrode sheet 200 can be 1 mm, and the depth of the first thinning area 110 can be 1 mm or 2 mm, which can effectively avoid the problem of low energy density of the battery cell 10 caused by the first positive tab 500. The projection of the second positive tab 600 falls within the projection range of the second thinning area 120, which specifically means that the width and length of the second positive tab 600 are equal to or less than the width and length of the second thinning area 120.That is, in the thickness direction of the body 100, the second positive lug 600 and the second thinning area 120 correspond, so that the size of the second positive lug 600 protruding out of the positive plate 200 is compensated by the second thinning area 120. For example, the size of the second positive lug 600 protruding out of the positive plate 200 can be 1mm, and the depth of the second thinning area 120 can be 1mm or 2mm, at this time, the problem of low energy density of the battery cell 10 caused by the second positive lug 600 can be effectively avoided. The projection of the negative lug 700 falls within the projection range of the third thinning area 130, which means that the width and length of the negative lug 700 are equal to or less than the width and length of the third thinning area 130. That is, in the thickness direction of the body 100, the negative lug and the third thinning area 130 correspond, so that the size of the negative lug 700 protruding out of the negative plate 300 is compensated by the third thinning area 130. For example, the size of the negative lug 700 protruding out of the negative plate 300 can be 1mm, and the depth of the third thinning area 130 can be 1mm or 2mm, at this time, the problem of low energy density of the battery cell 10 caused by the negative lug 700 can be effectively avoided. Specifically, in the thickness direction of the body 100, the projection of the first positive lug 500 falls within the projection range of the first thinning area 110, the projection of the second positive lug 600 falls within the projection range of the second thinning area 120, and the projection of the negative lug 700 falls within the projection range of the third thinning area 130. In the prior art, after the body 100 has multiple lugs, there is no thinning area on the body 100, so multiple lugs will cause the energy density of the battery cell 10 to be low. In the present application, the first thinning area 110 can provide a space for the first positive lug 500, thereby effectively avoiding the first positive lug 500 occupying too much size in the thickness direction of the body 100. Similarly, the second thinning area 120 can provide a space for the second positive lug 600, thereby effectively avoiding the second positive lug 600 occupying too much size in the thickness direction of the body 100. The third thinning area 130 can provide a space for the negative lug 700, thereby effectively avoiding the negative lug 700 occupying too much size in the thickness direction of the body 100. In this way, the energy density of the battery cell 10 of the present application is high. Specifically, the battery cell 10 can have a high energy density.

[0048] Further, the specific manners that the main body 100 is provided with the first thinning area 110, the second thinning area 120 and the third thinning area 130 are introduced as follows, please refer to FIG. 1 to FIG. 4. In some embodiments, the first thinning area 110, the second thinning area 120 and the third thinning area 130 are all arranged on the positive electrode sheet 200. Specifically, it is mentioned above that the main body 100 is formed by winding after the positive electrode sheet 200 and the negative electrode sheet 300 are stacked. Since the first thinning area 110, the second thinning area 120 and the third thinning area 130 can be formed by removing active material, after the first thinning area 110, the second thinning area 120 and the third thinning area 130 are all arranged on the positive electrode sheet 200, a part of the active material of the positive electrode can be removed, which can effectively avoid the problem of lithium precipitation of the battery cell 10.

[0049] Further, please refer to FIG. 3. In some embodiments, the first thinning area 110 is connected to the second thinning area 120. The first thinning area 110 being connected to the second thinning area 120 specifically means that the first thinning area 110 can be a groove, the second thinning area 120 can be a groove, and the groove and the groove are connected to each other. Such a manner can reduce the number of processing times on the positive electrode sheet 200 (processing the first thinning area 110 and the second thinning area 120 at one time), thereby improving the processing efficiency. In addition, please refer to FIG. 4. In other embodiments, two ends of the second thinning area 120 are respectively connected to the first thinning area 110 and the third thinning area 130. The two ends of the second thinning area 120 being respectively connected to the first thinning area 110 and the third thinning area 130 specifically means that the first thinning area 110 can be a groove, the second thinning area 120 can be a groove, the third thinning area 130 can be a groove, and the three grooves are connected to each other, which can also reduce the number of processing times and improve the processing efficiency. It can be conceived that in other embodiments, the second thinning area 120 is connected to the third thinning area 130.

[0050] Further, if the first thinning area 110, the second thinning area 120 and the third thinning area 130 are all arranged on the positive plate 200, it is possible to cause the amount of active material of the positive plate 200 to be small, and therefore, the first thinning area 110 and the second thining area 120 can be arranged on the positive plate 200, and the third thinning area 130 can be arranged on the negative plate 300. Specifically, referring to FIG. 5, in some embodiments, the first thinning area 110 and the second thinning area 120 are arranged on the positive plate 200, and the third thinning area 130 is arranged on the negative plate 300, and the positive plate 200 corresponding to the third thinning area 130 is provided with an insulating layer 1000. Among them, the first thinning area 110 and the second thinning area 120 are arranged on the positive plate 200, and the third thinning area 130 is arranged on the negative plate 300, which can make the amount of active material on the positive plate 200 less than the amount of active material on the negative plate 300, which can effectively avoid the problem of lithium precipitation of the battery cell 10. In addition, the insulating layer 1000 can also make the positive active material corresponding to the third thinning area 130 lose activity, thereby further effectively avoiding the problem of lithium precipitation of the battery cell 10.

[0051] Further, in some embodiments, the first thinning area 110, the second thinning area 120 and the third thinning area 130 are all arranged on the negative plate 300, and the positive plate 200 corresponding to the first thinning area 110, the second thinning area 120 and the third thinning area 130 is provided with an insulating layer 1000. Specifically, the insulating layer 1000 can make the positive active material corresponding to the first thinning area 110, the second thinning area 120 and the third thinning area 130 lose activity, thereby further effectively avoiding the problem of lithium precipitation of the battery cell 10.

[0052] Further, referring to FIG. 1, in some embodiments, the battery cell 10 further comprises two positive tab rubbers 800, and the two positive tab rubbers 800 are respectively attached to the first positive tab 500 and the second positive tab 600. Among them, the main function of the positive tab rubber 800 is insulation, which prevents the tab from directly contacting other parts of the battery (such as the aluminum plastic film) to cause short circuit. During the packaging process of the battery, the positive tab rubber 800 is bonded together with the aluminum plastic film by heating and hot melting, forming an effective insulating barrier to ensure the safe operation of the battery. In this way, after the two positive tab rubbers 800 are respectively attached to the first positive tab 500 and the second positive tab 600, the safety of the battery can be improved. Among them, the battery cell 10 further comprises a negative tab rubber 900, and the negative tab rubber 900 is attached to the negative tab 700.

[0053] Further, referring to FIG. 1, in some embodiments, the shoulder width of the positive tab adhesive 800 in the width direction of the main body 100 is M, 2mm≤M≤3mm. The shoulder width of the positive tab adhesive 800 refers to the part of the positive tab adhesive 800 that protrudes relative to the tab. The shoulder width of the positive tab adhesive 800 in the width direction of the main body 100 can be 2mm, 2.5mm, or 3mm. When the shoulder width of the positive tab adhesive 800 in the width direction of the main body 100 is less than 2mm, due to the small size of the positive tab adhesive 800, this can result in poor insulation of the positive tab adhesive 800. When the shoulder width of the positive tab adhesive 800 in the width direction of the main body 100 is greater than 3mm, under the premise that the positive tab adhesive 800 meets the insulation performance, the excessive size can result in waste of material.

[0054] Further, referring to FIGS. 1-6, in some embodiments, the distance between the first positive tab 500 and the second positive tab 600 in the width direction of the main body 100 is L1, L1≥7mm, L1≥2M. The distance between the first positive tab 500 and the second positive tab 600 in the width direction of the main body 100 can be 7mm, 8mm, or 9mm, etc. When the distance between the first positive tab 500 and the second positive tab 600 is relatively close, this can cause the first positive tab 500 and the second positive tab 600 to overlap in the thickness direction of the main body 100, which can increase the thickness of the battery cell 10, thereby making the energy density of the battery cell 10 smaller. In addition, when L1 is not less than 2M, this can make the packaging effect of the battery cell 10 better, thereby improving the reliability of the battery cell 10.

[0055] Further, referring to FIGS. 1-6, in some embodiments, the distance between the first positive tab 500 and the negative tab 700 in the width direction of the main body 100 is L2, L2-L1≥2M. When the distance between the second positive tab 600 and the negative tab 700 is relatively close, this can cause the second positive tab 600 and the negative tab 700 to contact, thereby causing the battery cell 10 to short circuit. When L2-L1≥2M is satisfied, the packaging effect of the battery cell 10 is good, and the reliability is high. For details, refer to Table 1.

[0056] Table 1

[0057] In which, the test method is to fill the inside of the top seal edge of the battery cell 10 with a penetrating liquid drop, clean it after standing for 10 minutes, and tear open the sol to observe whether there is a red trace channel. From the above table, it can be seen that when L2-L1≥2M is satisfied, the packaging effect of the battery cell 10 is better, and the pass rate is 100%, while when L2-L1≥2M is not satisfied, the packaging pass rate of the battery cell 10 is lower.

[0058] Further, referring to FIGS. 1-6, in some embodiments, the battery cell 10 further comprises a separator 400 between the positive electrode sheet 200 and the negative electrode sheet 300. Specifically, the main role of the separator 400 is to prevent the positive electrode sheet 200 and the negative electrode sheet 300 from directly contacting each other, thereby avoiding internal short circuit of the battery cell 10. At the same time, the separator 400 can also allow electrolyte ions (such as lithium ions) to pass freely during charging and discharging to complete the storage and release of electrical energy. The separator 400 has good insulation, ion permeability and certain mechanical strength. Specifically, the separator 400 is usually made of microporous materials such as polyethylene (PE), polypropylene (PP) or their composite materials. These materials have good insulation performance and can effectively prevent the positive and negative electrodes of the battery from directly contacting each other. At the same time, their microporous structure allows electrolyte ions to pass during charging and discharging, ensuring the normal operation of the battery

[0059] In some embodiments, the battery comprises: a housing and the battery cell 10 in the above embodiments. The housing has a storage cavity. The housing can be an aluminum plastic film or a metal housing 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 tab 500 falls within the projection range of the first thinning area 110, the projection of the second positive tab 600 falls within the projection range of the second thinning area 120, and the projection of the negative tab 700 falls within the projection range of the third thinning area 130. In the prior art, after the main body 100 has multiple tabs, the main body 100 has no thinning area, and therefore the multiple tabs can result in a low energy density of the battery cell 10. In the present application, the first thinning area 110 can provide a space for accommodating the first positive tab 500, thereby effectively preventing the first positive tab 500 from occupying too large a size in the thickness direction of the main body 100. Similarly, the second thinning area 120 can provide a space for accommodating the second positive tab 600, thereby effectively preventing the second positive tab 600 from occupying too large a size in the thickness direction of the main body 100. The third thinning area 130 can provide a space for accommodating the negative tab 700, thereby effectively preventing the negative tab 700 from occupying too large a size in the thickness direction of the main body 100. In this way, the battery cell 10 has a high energy density. Specifically, the battery cell 10 can have a high energy density. Further, the battery with the battery cell 10 has a high energy density.

[0060] In some embodiments, the electronic device includes the battery in the above embodiments. Specifically, along the thickness direction of the main body 100, the projection of the first positive tab 500 falls within the projection range of the first thinning area 110, the projection of the second positive tab 600 falls within the projection range of the second thinning area 120, and the projection of the negative tab 700 falls within the projection range of the third thinning area 130. In the prior art, after the main body 100 has multiple tabs, there is no thinning area on the main body 100, so the multiple tabs will cause the energy density of the battery cell 10 to be low. In the present application, the first thinning area 110 can provide a space for the first positive tab 500, thereby effectively avoiding the first positive tab 500 occupying too large a size in the thickness direction of the main body 100. Similarly, the second thinning area 120 can provide a space for the second positive tab 600, thereby effectively avoiding the second positive tab 600 occupying too large a size in the thickness direction of the main body 100. The third thinning area 130 can provide a space for the negative tab 700, thereby effectively avoiding the negative tab 700 occupying too large a size 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 high. Specifically, the battery cell 10 can have a high energy density. Further, the battery having the battery cell 10 has a high energy density. Still further, the electronic device having the battery has good endurance.

[0061] The embodiments of the present application are described in detail above with reference to the drawings, but the present application is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made to the embodiments of the present application without departing from the spirit of the present application. Furthermore, the embodiments of the present application and the features in the embodiments can be combined with each other without conflict.

Claims

1. An electric cell, comprising: a main body comprising a positive sheet and a negative sheet, the main body being formed by winding after layering the positive sheet and the negative sheet; a first positive tab electrically connected to the positive sheet; a second positive tab electrically connected to the positive sheet; a negative tab electrically connected to the negative sheet; wherein the first positive tab and the negative tab are respectively located on both sides of the second positive tab in a width direction of the main body; the main body is provided with a first thinning area, a second thinning area and a third thinning area, and in a thickness direction of the main body, a projection of the first positive tab falls within a projection range of the first thinning area, a projection of the second positive tab falls within a projection range of the second thinning area, and a projection of the negative tab falls within a projection range of the third thinning area.

2. The electric cell of claim 1, wherein, The first thinning area, the second thinning area and the third thinning area are all arranged on the positive sheet.

3. The electric cell of claim 2, wherein, The first thinning area is connected to the second thinning area.

4. The electric cell of claim 2, wherein, Two ends of the second thinning area are respectively connected to the first thinning area and the third thinning area.

5. The electric cell of claim 1, wherein, The first thinning area, the second thinning area and the third thinning area are all arranged on the negative sheet, and an insulating layer is arranged on the positive sheet corresponding to the first thinning area, the second thinning area and the third thinning area.

6. The electric cell of claim 1, wherein, The first thinning area and the second thinning area are arranged on the positive sheet, and the third thinning area is arranged on the negative sheet, and an insulating layer is arranged on the positive sheet corresponding to the third thinning area.

7. The electric cell of claim 1, wherein, The electric cell further comprises two positive tab rubbers, and the two positive tab rubbers are respectively attached to the first positive tab and the second positive tab.

8. The electric cell of claim 7, wherein, A shoulder width of the positive tab rubber in a width direction of the main body is M, and 2mm≤M≤3mm.

9. The electric cell of claim 8, wherein, In the width direction of the main body, a distance between the first positive tab and the second positive tab is L1, and L1≥2M.

10. The electric cell of claim 9, wherein, In the width direction of the main body, a distance between the first positive tab and the negative tab is L2, and L2-L1≥2M.

11. The electric cell of claim 1, wherein, The electric cell further comprises a separator, and the separator is located between the positive sheet and the negative sheet. 12.A battery, comprising: a shell having a storage cavity; the electric cell according to any one of claims 1 to 11, arranged in the storage cavity. 13.An electronic device comprising the battery according to claim 12.

Images