Battery

Abstract

The utility model relates to the technical field of battery cell assemblies, and particularly provides a battery which comprises a positive plate, a negative plate, a positive lug and a negative adapter plate, the positive plate comprises a positive current collector and a positive material layer, the positive material layer is provided with a positive tab groove, the positive tab comprises a body part arranged in the positive tab groove and an extending part extending out, and a first bending angle alpha is formed between the extending part and the positive current collector; the negative plate comprises a negative current collector and a negative soft tab, the negative soft tab comprises a lamination section and a collection section, the lamination section is formed by extending from one side of the negative current collector, the collection section is connected with the negative switching plate, a second bending angle beta is formed between the collection section and the negative current collector, and beta is smaller than alpha. The lamination section is connected with the multiple layers of negative plates and then is conducted with the negative adapter plate through the collection section, so that the current flux is improved, the internal resistance of the battery is reduced, the ion migration speed is accelerated, and the charge-discharge rate of the battery is improved; the angle between the converging section and the negative plate is small, the space of the head of the battery is reduced, and the energy density is increased.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of an electric cell assembly, and particularly discloses a battery. BACKGROUND

[0002] With the development of technology, batteries have been widely applied to the fields of electronic devices, electric vehicles and the like. At present, the market continuously puts forward new requirements for batteries, and not only needs to control the space occupied by the batteries, but also needs to improve the endurance and the charging and discharging rate of the batteries, which requires the batteries to improve the charging and discharging rate while pursuing high volume energy density, thereby forming a certain degree of challenge to the batteries in the related art. CONTENT OF THE UTILITY MODEL

[0003] The application aims to solve at least part of the technical problems mentioned in the above content, and the purpose is achieved by the following technical scheme:

[0004] The application discloses a battery, which comprises a positive electrode sheet, a negative electrode sheet, a shell for accommodating the positive electrode sheet and the negative electrode sheet, a positive electrode lug and a negative electrode adapter sheet. The positive electrode sheet comprises a positive electrode current collector and a positive electrode material layer located on the positive electrode current collector. The positive electrode material layer comprises a positive electrode lug groove exposing the positive electrode current collector, and the positive electrode lug is partially located in the positive electrode lug groove. The negative electrode sheet comprises a negative electrode current collector and a negative electrode material layer located on the negative electrode current collector. The negative electrode material layer comprises silicon-carbon composite material and / or silicon-oxygen composite material. The negative electrode sheet further comprises a negative electrode soft lug extending outward from one side of the negative electrode current collector. The positive electrode sheet and the negative electrode sheet are laminated and wound to form a winding core. The positive electrode lug comprises a body part located in the positive electrode lug groove and an extension part extending out of the positive electrode lug groove. A first bending angle α is formed between the extension part and the positive electrode current collector of the positive electrode sheet. The negative electrode soft lug is laminated to form a lamination section and a collection section connected with the lamination section. The collection section is located on the side of the lamination section away from the negative electrode current collector. The collection section is connected with the negative electrode adapter sheet. The negative electrode adapter sheet comprises a first negative electrode section and a second negative electrode section connected at an angle. The first negative electrode section is connected with the collection section. A fourth bending point is formed at the connection between the first negative electrode section and the second negative electrode section.

[0005] A second bending angle β is formed between the plane where the collection section is located and the plane where the negative electrode current collector is located, and β < α.

[0006] In some embodiments, 90° ≤ α ≤ 160°, and further, 50° ≤ β ≤ 150°.

[0007] In some embodiments, the battery further comprises a shell accommodating the positive electrode sheet and the negative electrode sheet, the shell having an edge sealing portion at one end along a length direction of the shell; the extension portion of the positive electrode tab comprises a first extension segment and a second extension segment connected to each other, the first extension segment being connected to the body portion of the positive electrode tab, the second extension segment extending from the edge sealing portion to an outside of the shell, the body portion and the second extension segment forming a first bending point and a second bending point at the connection points of the first extension segment, respectively; the connection point of the stacking segment of the negative electrode soft tab and the collection segment forms a third bending point; along a thickness direction of the battery, the first bending point and the third bending point are both located at the offset portion of the shell.

[0008] In some embodiments, the first bending point is located at a distance d1 from the one end of the shell where the edge sealing portion is located, the third bending point is located at a distance d2 from the one end of the shell where the edge sealing portion is located, and d2 < d1, 0.1 mm ≤ d1 ≤ 3 mm, and / or 0 mm < d2 ≤ 2.5 mm.

[0009] In some embodiments, the first bending point is located at a distance d3 from the nearest end of the shell along a thickness direction of the shell, the third bending point is located at a distance d4 from the nearest end of the shell along the thickness direction of the shell, and d4 < d3.

[0010] In some embodiments, the second negative electrode segment extends from the edge sealing portion to the outside of the shell, a distance between the third bending point and the fourth bending point along a length direction of the battery is d5, and 0.05 mm ≤ d5 ≤ 3 mm.

[0011] In some embodiments, the first negative electrode segment is connected to a side of the collection segment facing the negative electrode sheet.

[0012] In some embodiments, the battery further comprises a first insulating layer and a second insulating layer, the first insulating layer covering at least the first negative electrode segment and separating the first negative electrode segment from the negative electrode sheet, the second insulating layer covering at least the collection segment and separating the collection segment from an inner wall of the shell; the second negative electrode segment is covered with a negative electrode insulating adhesive, the negative electrode insulating adhesive having an overlapping portion with the first insulating layer and / or the second insulating layer; a size of the overlapping portion along a length direction of the battery is d6, and 0 mm < d6 ≤ 1 mm.

[0013] In some embodiments, the first insulating layer and the second insulating layer do not overlap with the negative electrode sheet along a thickness direction of the battery.

[0014] In some embodiments, a bending direction of the positive electrode tab and a bending direction of the negative electrode soft tab are opposite.

[0015] The technical solutions provided in the present application have at least the following technical effects:

[0016] In the present application, the laminated section of the negative soft tab is connected with the multi-layer negative plate, and then connected with the negative adapter plate through the collecting section of the negative soft tab, so that the current flux can be improved, the internal resistance of the battery can be reduced, the migration speed of ions can be accelerated, and the charging and discharging rate of the battery can be improved. Furthermore, the first bending angle between the extension and the positive current collector of the positive plate (110) is greater than the second bending angle between the plane where the collecting section is located and the plane where the negative current collector is located. On the one hand, the angle between the collecting section and the negative plate is relatively small, which reduces the space of the head of the battery, increases the volume energy density of the battery, and also prevents the expansion of the silicon-doped negative plate from easily driving the laminated section and the collecting section of the negative soft tab back during the formation process. If the angle is too large, the fourth bending point of the negative soft tab can easily exceed the overall thickness of the battery cell, even contact the shell and cause the bulging of the region. Furthermore, the angle formed by the positive extension is large, and correspondingly, under the premise of preventing the contact between the vertex of the soft tab and the shell, the expansion space of the silicon-oxygen composite material and / or the silicon-carbon composite material-doped negative plate in the length direction of the shell is reserved in advance during the charging and discharging process, preventing the silicon-oxygen composite material and / or the silicon-carbon composite material-doped negative plate from expanding and pressing the shell, which can cause the shell to break. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to better combine the content shown in the drawings of the specification with the content described in the specific embodiments, the drawings of the specification are briefly introduced as follows. It can be understood that the drawings of the specification mentioned below only schematically show the related technical solutions and some embodiments of the technical solutions of the present application, and under the premise of not paying creative labor, those skilled in the art can also make drawings showing other embodiments.

[0018] Specifically, the annotations of the drawings of the specification are as follows:

[0019] Figure 1 The first cross-sectional view of the battery described in some embodiments of the present application, wherein the positive tab is mainly shown;

[0020] Figure 2 The second cross-sectional view of the battery described in some embodiments of the present application, wherein the negative soft tab and the negative adapter plate are mainly shown;

[0021] Figure 3 The enlarged structural schematic view of Figure 1 , wherein the structure near one end of the sealing edge part of the shell is mainly shown;

[0022] Figure 4 The enlarged structural schematic view of Figure 2 , wherein the structure near one end of the sealing edge part of the shell is mainly shown.

[0023] Specifically, the annotations of the drawings of the specification are as follows:

[0024] 100. Battery; 110. Positive electrode plate; 120. Negative electrode plate; 130. Positive electrode tab; 140. Negative electrode adapter plate; 150. Negative electrode flexible tab; 160. Casing; 170. Separator; 131. Body section; 132. First extension section; 133. Second extension section; 141. First negative electrode section; 142. Second negative electrode section; 151. Lamination section; 152. Converging section; 161. Sealing section; 181. First insulating layer; 182. Second insulating layer; 183. Negative electrode insulating adhesive; 184. Positive electrode insulating adhesive; D1. First bending point; D2. Second bending point; D3. Third bending point; D4. Fourth bending point; X. Thickness direction; Y. Length direction. Detailed Implementation

[0025] To make the embodiments of this application clearer, they will be described below in conjunction with the accompanying drawings. It is to be understood that the content mentioned below is only a partial embodiment of this application, while the complete list of all embodiments is provided. Therefore, other embodiments obtained based on the following embodiments without any inventive effort all fall within the protection scope of this application.

[0026] It should be understood that the terminology used herein is for the purpose of describing specific embodiments only and is not intended to impose strict limitations on the technical solutions unless the context clearly indicates otherwise. For example, the use of "a," "an," and "the" to modify a feature does not preclude the possibility that the feature may be plural in other embodiments.

[0027] It should be understood that the terms "comprising," "including," and "having" are open-ended, indicating the presence of the stated features but not excluding the possibility of other features in the embodiment. Similarly, the use of terms such as "first," "second," etc., to describe multiple features only indicates the distinction between one feature and another, and such terms do not imply order or sequence unless explicitly stated in the context.

[0028] It should be understood that, unless the context clearly indicates otherwise, the terms "setup," "connection," and "installation" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integrated connection; they can refer to a direct connection or an indirect connection via a medium. Those skilled in the art will understand the specific meaning of these terms in this document based on the specific circumstances.

[0029] In addition, for ease of description, the text will use terms of spatial relative relationship to describe the position of one feature relative to another feature, such as "inner", "outer", "end", "side", "upper", "middle", "lower", "high", "low", "axial", "circumferential", "radial", "horizontal", "vertical", "first direction", "second direction", etc. It can be understood that the spatial relative relationship between two features should include other specific situations besides those shown in the accompanying drawings of the specification.

[0030] The embodiments of this application will now be described with reference to the accompanying drawings.

[0031] Reference Figures 1 to 4 This application provides an embodiment of a battery 100, which includes a positive electrode 110, a negative electrode 120, a positive electrode tab 130, and a negative electrode adapter 140. The positive electrode 110 includes a positive current collector and a positive electrode material layer on the positive current collector. The positive electrode material layer includes a positive electrode tab groove that exposes the positive current collector. The positive electrode tab 130 is partially located within the positive electrode tab groove. The negative electrode 120 includes a negative current collector and a negative electrode material layer on the negative current collector. The negative electrode 120 also includes a negative electrode soft tab 150 extending outward from one side of the negative current collector. The positive electrode 110 and the negative electrode tab... The core is formed by 120 layers of winding. The positive electrode tab 130 includes a body portion 131 located in the positive electrode tab groove and an extension portion extending out of the positive electrode tab groove. The extension portion forms a first bending angle α with the positive electrode current collector of the positive electrode plate 110. The negative electrode soft tab 150 is formed by stacking a stacked section 151 and a collecting section 152 connected to the stacked section 151. The collecting section 152 is located on the side of the stacked section 151 away from the negative electrode current collector. The collecting section 152 is connected to the negative electrode adapter plate 140. A second bending angle β is formed between the plane where the collecting section 152 is located and the plane where the negative electrode current collector is located, and β < α.

[0032] In this embodiment, the stacked segment 151 of the negative electrode tab 150 is connected to the multilayer negative electrode sheet 120, and then connected to the negative electrode adapter sheet 140 through the collecting segment 152 of the negative electrode tab 150. This reduces the internal resistance of the battery 100, increases the current flow, accelerates the migration speed of ions, and improves the charge and discharge rate of the battery 100. Furthermore, the first bending angle formed between the extension and the positive electrode current collector of the positive electrode sheet 110 is greater than the second bending angle formed between the plane of the collecting segment and the plane of the negative electrode current collector. Firstly, the angle between the collecting segment and the negative electrode sheet is relatively small, reducing the space at the battery head and increasing the volumetric energy density of the battery. Secondly, it can prevent damage during the formation process. In the process, the expansion of the silicon-doped negative electrode sheet can easily cause the stacked and converged sections of the negative electrode tab to retract. If the angle is too large, the fourth bending point of the negative electrode tab may exceed the overall thickness of the cell, or even contact the casing, causing the casing to bulge or crack in that area. Furthermore, the angle formed by the positive electrode extension is relatively large. Correspondingly, in addition to preventing the tip of the tab from contacting the casing, expansion space is reserved in the length direction of the casing in advance for the expansion of the negative electrode sheet doped with silicon-oxygen composite material and / or silicon-carbon composite material during the charging and discharging process. This prevents the expansion of the negative electrode sheet doped with silicon-oxygen composite material and / or silicon-carbon composite material from squeezing the casing and causing the casing to crack.

[0033] It should be noted that, referring to Figure 3 and Figure 4 The positive electrode tab 130 is directly connected to the positive electrode plate 110, while the negative electrode adapter 140 (also known as the negative electrode rigid tab) is connected to the negative electrode plate 120 through the negative electrode flexible tab 150. Due to the presence of the stacked section 151 in the negative electrode flexible tab 150, the starting bending point of the negative electrode flexible tab 150 is closer to the end of the battery 100 in the length direction Y (i.e., the head of the battery 100) than the starting bending point of the positive electrode tab 130. In other words, the third bending point D3 is closer to the end of the battery 100 in the length direction Y than the first bending point D1. Therefore, in order to shorten the length direction Y dimension of the battery 100, the slope of the converging section 152 of the negative electrode flexible tab 150 should be greater, that is, the second bending angle β between the converging section 152 and the negative electrode plate 120 should be smaller than the first bending angle α between the positive electrode tab 130 and the positive electrode plate 110.

[0034] Furthermore, in this embodiment, reference is made to Figure 3 and Figure 4The body 131 of the positive electrode tab 130 overlaps with the positive electrode sheet 110 along the thickness direction X of the battery 100, and the stacked segment 151 of the negative electrode tab 150 is connected to one end of the negative electrode sheet 120 along the length direction Y of the battery 100. Specifically, there are multiple stacked segments 151, and each stacked segment 151 is connected to one side of the multi-layer negative electrode sheet 120 along its length direction Y, so that the multiple stacked segments 151 and the negative electrode sheet 120 do not overlap in the thickness direction X of the battery 100, thereby ensuring the flatness of the core and preventing the expansion of the negative electrode sheet 120 during charge and discharge cycles, which would cause the size of the connection point along the thickness direction X of the battery 100 to become too large and damage the casing 160. In contrast, the positive tab 130 is only connected to one layer of positive electrode 110, and the positive electrode 110 generally does not expand or expands only slightly. Therefore, the main body 131 of the positive tab 130 is directly connected to the positive electrode 110 along its thickness direction X without affecting the battery 100. At the same time, it can increase the connection area between the two and increase the connection strength.

[0035] In some embodiments, refer to Figure 3 and Figure 4 , 90°≤α≤160°, and further, 50°≤β≤150°.

[0036] It should be noted that the first bending angle α between the positive electrode tab 130 and the positive electrode plate 110 cannot be too small; otherwise, the positive electrode tab 130 may easily interfere with the positive electrode plate 110, causing damage to the positive electrode tab 130 and / or the positive electrode plate 110. At the same time, the first bending angle α cannot be too large either; otherwise, the positive electrode tab 130 may interfere with the housing 160, causing damage to the positive electrode tab 130 and / or the housing 160, or making the size of the housing 160 along its length direction Y too large. Therefore, the first bending angle α should be moderate; for example, α can be any one of 90°, 100°, 110°, 120°, 130°, 140°, 150°, and 160°, or a range of any two of these values.

[0037] Similarly, the second bending angle β between the collecting section 152 and the negative electrode 120 should not be too small. Otherwise, the collecting section 152 may easily interfere with the stacked section 151, causing compression of the stacked section 151, which in turn may compress the negative electrode 120, potentially damaging the stacked section 151, the collecting section 152, and / or the negative electrode 120. At the same time, the second bending angle β should not be too large either. Otherwise, the collecting section 152 may interfere with the housing 160, causing damage to the collecting section 152 and / or the housing 160, or making the size of the housing 160 too large along the length Y direction of the battery 100. Therefore, the second bending angle β should also be moderate. For example, while ensuring that β is less than α, β can take any one or any two of the following values: 50°, 60°, 70°, 80°, 90°, 100°, 110°, 120°, 130°, 140°, and 150°.

[0038] Optionally, the battery 100 is a pouch battery, and the casing 160 is an aluminum-plastic film.

[0039] In some embodiments, refer to Figure 1 and Figure 2 The battery 100 also includes a housing 160 that houses the positive electrode 110 and the negative electrode 120. One end of the housing 160 along its length direction Y has a sealed edge portion 161. The extension portion of the positive electrode tab 130 includes a first extension segment 132 and a second extension segment 133 connected to each other. The first extension segment 132 is connected to the body portion 131 of the positive electrode tab 130. The second extension segment 133 extends from the sealed edge portion 161 to the outside of the housing 160. The connection points between the body portion 131 and the second extension segment 133 and the first extension segment 132 respectively form a first bending point D1 and a second bending point D2. The connection point between the stacked segment 151 and the converging segment 152 of the negative electrode soft tab 150 forms a third bending point D3. Along the thickness direction X of the battery 100, the first bending point D1 and the third bending point D3 are both located at the offset portion of the housing 160.

[0040] It should be noted that, referring to Figure 1 The first bending point D1 is located at an offset position of the housing 160 along its thickness direction X, that is, the connection position between the positive electrode tab 130 and the positive electrode sheet 110 (that is, the position where the body part 131 of the positive electrode tab 130 is connected to one of the positive electrode sheets 110) is located at an offset position of the housing 160 along its thickness direction X (that is, a non-central position). Specifically, when the positive electrode sheet 110 and the negative electrode sheet 120 are wound into a core, the end of the positive electrode sheet 110 starts to be wound from the inside out. After winding, the end of the positive electrode sheet 110 is approximately located at the very center of the core, that is, the end of the positive electrode sheet 110 is located at the center position of the housing 160 along its thickness direction X. Therefore, the connection position between the positive tab 130 and the positive electrode plate 110 is located at a non-central position along the thickness direction X of the housing 160. This means that the positive tab 130 is not connected to the end of the positive electrode plate 110. That is, when the positive electrode plate 110 is unfolded, the positive tab 130 is centered or slightly offset on the positive electrode plate 110. Compared with the positive tab 130 being connected to the end of the positive electrode plate 110, this arrangement shortens the electron movement time and improves the charge and discharge rate of the battery 100. (Simplified view, when the positive tab 130 is connected to the end of the positive electrode plate 110, the positive tab 130 is centered or slightly offset on the positive electrode plate 110.) When the positive electrode 110 is located at one end, electrons at the other end need to travel the entire length of the positive electrode 110 to reach the positive electrode tab 130. In other words, it takes a relatively long time for all moving electrons on the positive electrode 110 to travel to the positive electrode tab 130. However, when the positive electrode tab 130 is located in the middle of the positive electrode 110, electrons at both ends of the positive electrode 110 only need to travel half the length of the positive electrode 110 to reach the positive electrode tab 130. In other words, it takes a relatively short time for all moving electrons on the positive electrode 110 to travel to the positive electrode tab 130.

[0041] In addition, refer to Figure 2 Since the converging section 152 is a standard part with a fixed length, if the third bending point D3 is located in the middle of the housing 160 along the X direction, the top of the converging section 152 will interfere with the housing 160, which may easily damage the converging section 152 and / or the housing 160. Therefore, the third bending point D3 is located at the offset part of the housing 160 along the X direction, so that the converging section 152 and the housing 160 avoid each other.

[0042] In particular, the collecting section 152 of the negative electrode soft tab 150 and the first negative electrode section 141 of the negative electrode adapter 140 are overlapped, which has good connection firmness and current conduction effect.

[0043] In some embodiments, refer to Figure 3 and Figure 4 The distance between the first bending point D1 and the end of the shell 160 with the sealing part 161 is d1, and the distance between the third bending point D3 and the end of the shell 160 with the sealing part 161 is d2, and d2 < d1 is satisfied.

[0044] In this embodiment, the third bending point D3 is closer to the end of the battery 100 along the length direction Y than the first bending point D1, that is, d2 < d1. Its effect is similar to the effect of β < α described above, that is, shortening the size of the battery 100 along the length direction Y and increasing the energy density.

[0045] In some embodiments, 0.1mm ≤ d1 ≤ 3mm, and / or 0mm < d2 ≤ 2.5mm.

[0046] In this embodiment, similar to the analysis of the values ​​of α and β described above, the values ​​of d1 and d2 should also be appropriate. For example, d1 can take any one of 0.1mm, 0.5mm, 1mm, 1.5mm, 2mm, 2.5mm, and 3mm, or a range of any two of these values. Similarly, while ensuring that d2 < d1, d2 can take any one of 0.1mm, 0.5mm, 1mm, 1.5mm, 2mm, and 2.5mm, or a range of any two of these values.

[0047] In some embodiments, refer to Figure 3 and Figure 4 The distance between the first bending point D1 and the nearest end of the shell 160 along the thickness direction X is d3, and the distance between the third bending point D3 and the nearest end of the shell 160 along the X direction is d4, and d4 < d3 is satisfied.

[0048] In this embodiment, referring to the above description, the third bending point D3 is closer to one end of the housing 160 along its thickness direction X than the first bending point D1, thereby ensuring that the top of the converging section 152 avoids mutual avoidance with the housing 160.

[0049] In some embodiments, refer to Figure 4 The distance along the Y direction between the third bend point D3 and the fourth bend point D4 is d5, and satisfies 0.05mm≤d5≤3mm.

[0050] In this embodiment, referring to the above description, if the distance d5 between the third bending point D3 and the fourth bending point D4 along the length Y direction of the battery 100 is too small, the collecting segment 152 is prone to interfering with the stacked segment 151, causing compression of the stacked segment 151, thereby compressing the negative electrode 120, which may damage the stacked segment 151, the collecting segment 152, and / or the negative electrode 120. If d5 is too large, the collecting segment 152 will interfere with the housing 160, causing damage to the collecting segment 152 and / or the housing 160, or making the size of the housing 160 along the length Y direction too large. Therefore, d5 should be moderate. For example, d5 can be any one of 0.05mm, 0.1mm, 0.5mm, 1mm, 1.5mm, 2mm, 2.5mm, and 3mm, or a range of any two of these values.

[0051] In some embodiments, refer to Figure 2 The first negative electrode section 141 and the collecting section 152 are connected to the side facing the negative electrode plate 120.

[0052] In this embodiment, the first negative electrode segment 141 of the negative electrode adapter 140 is connected to the side of the collecting segment 152 facing away from the housing 160, thereby keeping the first negative electrode segment 141 away from the housing 160 and preventing the negative electrode adapter 140 from directly contacting the housing 160 and causing a short circuit.

[0053] In some embodiments, refer to Figure 2 The battery 100 also includes a first insulating layer 181 and a second insulating layer 182. The first insulating layer 181 covers at least the first negative electrode section 141 and isolates the first negative electrode section 141 from the negative electrode sheet 120. The second insulating layer 182 covers at least the collecting section 152 and isolates the collecting section 152 from the inner wall of the housing 160.

[0054] In this embodiment, the first insulating layer 181 is used to prevent the negative electrode adapter 140 from being directly connected to the negative electrode plate 120, which would cause the negative electrode tab 150 to fail and thus affect the charge and discharge rate. The second insulating layer 182 is used to prevent the collecting section 152 from being connected to the housing 160, which would cause a short circuit.

[0055] In some embodiments, the second negative electrode segment 142 is covered with negative electrode insulating adhesive 183, and the negative electrode insulating adhesive 183 overlaps with the first insulating layer 181 and / or the second insulating layer 182.

[0056] In this embodiment, the negative electrode insulating adhesive 183 is used to prevent the second negative electrode segment 142 of the negative electrode adapter 140 from contacting the housing 160 and causing a short circuit. The negative electrode insulating adhesive 183 is overlapped with the above-mentioned insulating layer, thereby further ensuring the insulation between the negative electrode tab and the housing 160.

[0057] In some embodiments, the dimension of the overlapping portion along the length direction Y of the battery 100 is d6, and satisfies 0mm < d6 ≤ 1mm.

[0058] In this embodiment, the dimension d6 of the overlapping portion along the length Y of the battery 100 should not be too large, otherwise the first insulating layer 181 and / or the second insulating layer 182 will be exposed from the sealing edge 161 of the housing 160, affecting the flatness of the housing 160 and the subsequent assembly of the battery 100. For example, d6 can be any one of 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm and 1mm or any two of these values.

[0059] In some embodiments, the first insulating layer 181 and the second insulating layer 182 do not overlap with the negative electrode 120 along the thickness direction X of the battery 100.

[0060] In this embodiment, the first insulating layer 181 and the second insulating layer 182 do not overlap with the negative electrode sheet 120 along the thickness direction X of the battery 100. That is, neither the first insulating layer 181 nor the second insulating layer 182 can extend too far in the direction of the negative electrode sheet 120 to cover the negative electrode sheet 120. This can ensure the flatness of the core and avoid the first insulating layer 181 and the second insulating layer 182 from affecting the lithium intercalation capability of the negative electrode sheet 120.

[0061] It should be noted that, referring to Figure 1 The second extension 133 of the positive electrode tab 130 is also covered with positive electrode insulating adhesive 184, thereby preventing the positive electrode tab 130 from directly contacting the housing 160. In some embodiments not shown in the figures, the positive electrode tab 130 is also provided with an insulating layer to cover the first extension 132. Similarly, the positive electrode insulating adhesive 184 on the second extension 133 and the insulating layer on the first extension 132 may overlap.

[0062] In some embodiments, refer to Figure 1 and Figure 2 The bending direction of the positive electrode tab 130 is opposite to that of the bending direction of the negative electrode soft electrode tab 150.

[0063] In this embodiment, the bending direction of the positive electrode tab 130 is opposite to the bending direction of the negative electrode soft tab 150, so as to... Figure 1 and Figure 2Taking the illustrated case as an example, the first extension 132 of the positive electrode tab 130 is bent upward relative to the body portion 131, while the stacked portion 151 of the negative electrode soft tab 150 is bent downward relative to the negative electrode sheet 120 (it should be understood that in some other embodiments, the first extension 132 of the positive electrode tab 130 may be bent downward relative to the body portion 131, while the stacked portion 151 of the negative electrode soft tab 150 may be bent upward relative to the negative electrode sheet 120). In this way, the positive electrode tab 130 and the negative electrode soft tab 150 are staggered in the thickness direction X of the battery 100, which prevents them from interfering with each other and causing a short circuit, and can also improve the utilization rate of the head space of the battery 100.

[0064] In particular, the term "and / or" in this application should be understood as follows:

[0065] In the first case, the term “and / or” located between the first subject and the second subject includes any of the following meanings: (1) only the first subject; (2) only the second subject; and (3) both the first subject and the second subject.

[0066] In the second case, the term "and / or" between the last two of three or more subjects means including at least any one of the subjects. For example, "first subject, second subject and / or third subject" has the same meaning as "first subject and / or second subject and / or third subject", specifically including the following combinations: (1) only the first subject; (2) only the second subject; (3) only the third subject; (4) first subject and second subject and no third subject; (5) first subject and third subject and no second subject; (6) second subject and third subject and no first subject; and (7) first subject, second subject and third subject;

[0067] Furthermore, the character " / " in this application generally indicates that the objects before and after it are in an "or" relationship.

[0068] In particular, although the embodiments of this application have been described above in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the concept of this application, and such modifications and variations all fall within the scope of protection of this application.

Claims

1. A battery, characterized in that, It includes a positive electrode (110), a negative electrode (120), a housing (160) for accommodating the positive electrode (110) and the negative electrode (120), a positive electrode tab (130), and a negative electrode adapter (140); The positive electrode sheet (110) includes a positive current collector and a positive electrode material layer located on the positive current collector. The positive electrode material layer includes a positive electrode tab groove that exposes the positive current collector. The positive electrode tab (130) is partially located in the positive electrode tab groove. The negative electrode sheet (120) includes a negative electrode current collector and a negative electrode material layer located on the negative electrode current collector. The negative electrode material layer includes a silicon-carbon composite material and / or a silicon-oxygen composite material. The negative electrode sheet (120) also includes a negative electrode soft tab (150) extending outward from one side of the negative electrode current collector. The positive electrode (110) and the negative electrode (120) are stacked and wound to form a core. The positive electrode tab (130) includes a body portion (131) located in the positive electrode tab groove and an extension portion extending out of the positive electrode tab groove. The extension portion forms a first bending angle α with the positive electrode current collector of the positive electrode (110). The negative electrode soft tab (150) is stacked to form a stacked section (151) and a collecting section (152) connected to the stacked section (151). The collecting section (152) is located on the side of the stacked section (151) away from the negative electrode current collector. The collecting section (152) is connected to the negative electrode adapter (140). The negative electrode adapter (140) includes a first negative electrode segment (141) and a second negative electrode segment (142) connected by a corner. The first negative electrode segment (141) is connected to the collection segment (152). The connection between the first negative electrode segment (141) and the second negative electrode segment (142) forms a fourth bending point (D4). The plane where the collecting section (152) is located forms a second bending angle β with the plane where the negative electrode current collector is located, and β < α.

2. The battery according to claim 1, characterized in that, 90°≤α≤160°, and further, 50°≤β≤150°.

3. The battery according to claim 1, characterized in that, The housing (160) has a sealing edge (161) at one end along its length direction (Y); The extension of the positive electrode tab (130) includes a first extension segment (132) and a second extension segment (133) connected to each other. The first extension segment (132) is connected to the body portion (131) of the positive electrode tab (130). The second extension segment (133) extends from the sealing portion (161) to the outside of the housing (160). The connection points of the body portion (131) and the second extension segment (133) with the first extension segment (132) respectively form a first bending point (D1) and a second bending point (D2). The connection between the stacked section (151) and the converging section (152) of the negative electrode soft tab (150) forms the third bending point (D3); Along the thickness direction (X) of the battery (100), the first bending point (D1) and the third bending point (D3) are both located at the offset portion of the housing (160).

4. The battery according to claim 3, characterized in that, The distance between the first bending point (D1) and the end of the shell (160) with the sealing part (161) is d1, and the distance between the third bending point (D3) and the end of the shell (160) with the sealing part (161) is d2, and satisfies d2<d1, 0.1mm≤d1≤3mm, and / or 0mm<d2≤2.5mm.

5. The battery according to claim 3, characterized in that, The distance between the first bending point (D1) and the nearest end of the shell (160) along its thickness direction (X) is d3, and the distance between the third bending point (D3) and the nearest end of the shell (160) along its thickness direction (X) is d4, and d4 < d3.

6. The battery according to claim 3, characterized in that, The second negative electrode section (142) extends from the sealing portion (161) to the outside of the housing (160); The distance between the third bending point (D3) and the fourth bending point (D4) along the length direction (Y) of the battery (100) is d5, and satisfies 0.05mm≤d5≤3mm.

7. The battery according to claim 6, characterized in that, The first negative electrode segment (141) is connected to the side of the collecting segment (152) facing the negative electrode plate (120).

8. The battery according to claim 7, characterized in that, The battery (100) further includes a first insulating layer (181) and a second insulating layer (182), wherein the first insulating layer (181) covers at least the first negative electrode section (141) and isolates the first negative electrode section (141) from the negative electrode sheet (120), and the second insulating layer (182) covers at least the collecting section (152) and isolates the collecting section (152) from the inner wall of the housing (160); The second negative electrode segment (142) is covered with negative electrode insulating adhesive (183), and the negative electrode insulating adhesive (183) overlaps with the first insulating layer (181) and / or the second insulating layer (182); The overlapping portion has a dimension of d6 along the length direction (Y) of the battery (100), and satisfies 0mm < d6 ≤ 1mm.

9. The battery according to claim 8, characterized in that, The first insulating layer (181) and the second insulating layer (182) do not overlap with the negative electrode sheet (120) along the thickness direction (X) of the battery (100).

10. The battery according to any one of claims 1 to 9, characterized in that, The bending direction of the positive electrode tab (130) is opposite to that of the bending direction of the negative electrode soft electrode tab (150).

Images