Battery cell, battery and vehicle

Abstract

The utility model discloses a battery cell, a battery and a vehicle, the battery cell comprises a pole piece and a diaphragm, and the diaphragm and the pole piece are laminated. The diaphragm comprises a base membrane, a first coating and a second coating, the adhesion of the first coating is greater than that of the second coating, and the wettability of the second coating is greater than that of the first coating. At least one first coating and at least one second coating are respectively coated on the base film, so that the wettability of a pole piece in the middle of the battery cell is greater than that of a pole piece at the edge of the battery cell on an orthographic projection surface in the thickness direction of the battery cell; and the adhesion between the diaphragm at the edge of the battery cell and the pole piece is greater than that between the diaphragm at the middle part of the battery cell and the pole piece. According to the battery cell and the battery, the wettability of the pole pieces can be improved, and the adhesion of the pole pieces can be ensured. Therefore, the reliability of the vehicle using the battery is improved.

Description

Technical Field

[0001] The present disclosure relates to the field of battery technology, and in particular to a battery cell, a battery and a vehicle. Background Art

[0002] With the vigorous development of electric vehicles, energy storage industry, electronic products and other industries, the research and development of large-capacity, long-life, high-safety, and fast-charging batteries has received widespread attention. As one of the core materials in the battery, the diaphragm is placed between the positive and negative electrodes of the battery to isolate the positive and negative electrodes and provide a lithium ion migration channel. The diaphragm plays a vital role in the internal resistance, cycle performance, safety, and charge and discharge performance of lithium-ion batteries.

[0003] In the related technology, the wettability of the diaphragm is not enough to support the fast charging capability of the battery throughout its life cycle, but if the wettability of the diaphragm is selectively improved, the adhesion of the diaphragm will be reduced. The reduction of the adhesion of the diaphragm will cause poor control of the gap between the finished battery pole pieces, as well as safety and life attenuation problems such as fast charging and lithium deposition derived from poor adhesion. Utility Model Content

[0004] In view of this, the present disclosure provides a battery cell, a battery and a vehicle, wherein the battery cell can both improve the wettability of the electrode piece and ensure the adhesion of the electrode piece.

[0005] Specifically, the present disclosure is implemented through the following technical solutions.

[0006] According to the first aspect of the embodiment of the present disclosure, a battery cell is provided, comprising a pole piece and a diaphragm, wherein the diaphragm and the pole piece are stacked. The diaphragm comprises a base film, a first coating and a second coating, wherein the adhesion of the first coating is greater than the adhesion of the second coating, and the wettability of the second coating is greater than the wettability of the first coating. At least one first coating and at least one second coating are applied to the base film respectively, so that on the orthographic projection surface in the thickness direction of the battery cell, the wettability of the pole piece in the middle of the battery cell is greater than the wettability of the pole piece at the edge of the battery cell, and the adhesion between the diaphragm at the edge of the battery cell and the pole piece is greater than the adhesion between the diaphragm and the pole piece in the middle of the battery cell.

[0007] The technical solution provided by the embodiments of the present disclosure may include the following beneficial effects.

[0008] By applying at least one first coating and at least one second coating on the base film respectively, the adhesion of the first coating is greater than that of the second coating, and the wettability of the second coating is greater than that of the first coating. The wettability of the middle part of the battery cell is greater than that of the edge of the battery cell, that is, the wettability of the pole piece located in the middle of the battery cell is greater than that of the pole piece located at the edge of the battery cell. And the adhesion between the diaphragm and the pole piece at the edge of the battery cell is greater than the adhesion between the diaphragm and the pole piece in the middle of the battery cell. Thereby, the wettability of the pole piece and the diaphragm is improved, and the adhesion between the pole pieces and between the pole piece and the diaphragm is guaranteed. Then the service life of the battery cell is guaranteed, the long-term fast charging capability is improved, and the safety of the battery cell is improved.

[0009] The technical solution of the present disclosure is further described below.

[0010] In one embodiment, on the orthographic projection surface in the thickness direction of the battery cell, the battery cell includes a first region located in the middle of the battery cell and a second region located at the edge of the battery cell. The sum of the areas of the first coating located in the second region is greater than the sum of the areas of the first coating located in the first region. The sum of the areas of the second coating located in the first region is greater than the sum of the areas of the second coating located in the second region.

[0011] In one embodiment, the first coating layer and the second coating layer are in strip shape, the first coating layer and the second coating layer are spaced apart along the width direction of the base film, and the area of ​​the first coating layer is smaller than the area of ​​the second coating layer.

[0012] In one embodiment, the first coating and the second coating are both in strip shape, and multiple first coatings and multiple second coatings are arranged in sequence along the length direction of the base film, and on the orthographic projection surface in the thickness direction of the battery cell, the first coating is applied at both ends of the base film along the length direction of the base film.

[0013] In one embodiment, the first coating layer is rectangular in shape, and a plurality of first coating layers are spaced apart along the length direction and the width direction of the base film, and the second coating layer is applied between the plurality of first coating layers.

[0014] In one embodiment, on the orthographic projection surface in the thickness direction of the battery cell, the battery cell includes a first region located in the middle of the battery cell and a second region located at the edge of the battery cell. The areas of the plurality of rectangular first coatings are not equal, and the area of ​​the second coating located in the first region is greater than 1 / 2 of the area of ​​the first region.

[0015] In one embodiment, on the orthographic projection surface in the thickness direction of the battery cell, the battery cell includes a first region located in the middle of the battery cell and a third region located on the diagonal of the battery cell. The sum of the areas of the second coating located in the first region and the third region is greater than 1 / 2 of the sum of the areas of the first region and the third region.

[0016] In one embodiment, the first coating is applied to at least a portion of an edge of the battery cell, avoiding the middle of the battery cell.

[0017] In one embodiment, the second coating is applied to at least a portion of the middle portion of the battery cell, avoiding the edge of the battery cell.

[0018] According to a second aspect of an embodiment of the present application, a battery is further provided, comprising a shell assembly and a battery cell according to any of the above embodiments, wherein the shell assembly is provided with a receiving cavity, the battery cell is arranged in the receiving cavity, and the receiving cavity is filled with an electrolyte.

[0019] The technical solution provided by the embodiments of the present disclosure may include the following beneficial effects.

[0020] The battery uses the battery cell in any of the above embodiments, which improves the wettability of the pole piece and ensures the adhesion of the pole piece, thereby ensuring the service life of the battery, improving the long-term fast charging capability and improving the safety of the battery.

[0021] According to a third aspect of an embodiment of the present application, a vehicle is also provided, comprising the battery of the above embodiment.

[0022] The technical solution provided by the embodiments of the present disclosure may include the following beneficial effects.

[0023] The vehicle uses the battery in the above embodiment, which improves the battery's service life, long-term fast charging capability, and battery safety, thereby improving the reliability of the vehicle.

[0024] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] BRIEF DESCRIPTION OF THE DRAWINGS The drawings constituting a part of the present disclosure are used to provide a further understanding of the present disclosure. The illustrative embodiments of the present disclosure and the description thereof are used to explain the present disclosure and do not constitute an improper limitation on the present disclosure.

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0027] Figure 1 FIG. 4 is a schematic diagram of the structure of a battery shown in an embodiment.

[0028] Figure 2 FIG. 4 is a schematic diagram of the structure of a diaphragm shown in an embodiment.

[0029] Figure 3 FIG. 4 is a schematic diagram of the structure of a diaphragm shown in an embodiment.

[0030] Figure 4 FIG. 4 is a schematic diagram of the structure of a diaphragm shown in an embodiment.

[0031] Figure 5 FIG. 4 is a schematic diagram of the structure of a diaphragm shown in an embodiment.

[0032] Figure 6 FIG. 4 is a schematic diagram of the structure of a diaphragm shown in an embodiment.

[0033] Figure 7 FIG. 4 is a schematic diagram of the structure of a diaphragm shown in an embodiment.

[0034] Figure 8 FIG. 4 is a schematic diagram of the structure of a diaphragm shown in an embodiment.

[0035] Fig. 9 The figure is a schematic diagram of the structure of a vehicle shown in an embodiment.

[0036] Description of Figure Numbers.

[0037] 1. Vehicle; 10. Battery; 100. Battery cell; 110. Pole piece; 120. Diaphragm; 121. Base film; 122. First coating layer; 123. Second coating layer; 200. Housing assembly; 210. Accommodating cavity; a. First region; b. Second region; c. Third region. DETAILED DESCRIPTION

[0038] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present disclosure. Instead, they are merely examples of devices and methods consistent with some aspects of the present disclosure as detailed in the appended claims.

[0039] The terms used in this disclosure are for the purpose of describing specific embodiments only and are not intended to limit the disclosure. The singular forms "a", "an" and "the" used in this disclosure and the appended claims are also intended to include plural forms unless the context clearly indicates otherwise. It should also be understood that the term "and / or" used herein refers to and includes any or all possible combinations of one or more associated listed items.

[0040] It should be understood that although the terms first, second, third, etc. may be used in the present disclosure to describe various information, such information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of the present disclosure, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Depending on the context, the word "if" as used herein may be interpreted as "at the time of" or "when" or "in response to determining".

[0041] With the vigorous development of electric vehicles, energy storage industry, electronic products and other industries, the research and development of large-capacity, long-life, high-safety and fast-charging batteries has attracted widespread attention. At present, there are many types and brands of batteries, which makes consumers have many choices. How to win the favor of consumers and improve product competitiveness has become an issue that battery manufacturers are paying more and more attention to.

[0042] As one of the core materials in the battery, the diaphragm is placed between the positive and negative electrodes of the battery to isolate the positive and negative electrodes and provide a channel for the migration of lithium ions. The diaphragm plays a vital role in the internal resistance, cycle performance, safety, and charge and discharge performance of lithium-ion batteries. In related technologies, the wettability of the diaphragm is not sufficient to support the fast charging capability of the battery throughout its life cycle, but if the wettability of the diaphragm is selectively improved, the adhesion of the diaphragm will be reduced. The reduction in the adhesion of the diaphragm will also cause poor control of the gap between the finished battery pole pieces, as well as safety and life attenuation issues such as fast charging and lithium precipitation derived from poor adhesion.

[0043] Based on this, the present disclosure provides a cell 100, a battery 10 and a vehicle 1, which can both improve the wettability of the pole piece 110 and ensure the adhesion of the pole piece 110, thereby improving the reliability of the vehicle 1 using the battery 10.

[0044] The technical solution of the present disclosure is further described below in conjunction with the specific structural drawings.

[0045] In order to better understand the battery cell 100 of the present disclosure, a battery 10 to which the battery cell 100 is applied is used for illustration.

[0046] like Figure 1 As shown, a battery 10 is provided, the battery 10 includes a battery cell 100 and a housing assembly 200, the housing assembly 200 is provided with a receiving cavity 210, the battery cell 100 is arranged in the receiving cavity 210, and the receiving cavity 210 is filled with an electrolyte. The battery cell 100 can improve the wettability of the electrode sheet 110 and the diaphragm 120 in the electrolyte, and can ensure the adhesion between the electrode sheets 110 and between the electrode sheets 110 and the diaphragm 120.

[0047] Specifically, Figures 1 to 8As shown, the battery cell 100 includes a pole piece 110 and a diaphragm 120, and the diaphragm 120 and the pole piece 110 are stacked. The diaphragm 120 includes a base film 121, a first coating 122 and a second coating 123, the adhesion of the first coating 122 is greater than the adhesion of the second coating 123, and the wettability of the second coating 123 is greater than the wettability of the first coating 122. At least one first coating 122 and at least one second coating 123 are applied to the base film 121 respectively, so that on the orthographic projection surface in the thickness direction of the battery cell 100, the wettability of the pole piece 110 in the middle of the battery cell 100 is greater than the wettability of the pole piece 110 at the edge of the battery cell 100, and the adhesion between the diaphragm 120 and the pole piece 110 at the edge of the battery cell 100 is greater than the adhesion between the diaphragm 120 and the pole piece 110 in the middle of the battery cell 100.

[0048] In this way, by applying at least one first coating 122 and at least one second coating 123 on the base film 121, the adhesion of the first coating 122 is greater than that of the second coating 123, and the wettability of the second coating 123 is greater than that of the first coating 122. The wettability of the middle of the battery cell 100 is greater than that of the edge of the battery cell 100, that is, the wettability of the pole piece 110 located in the middle of the battery cell 100 is greater than that of the pole piece 110 located at the edge of the battery cell 100. And the adhesion between the diaphragm 120 and the pole piece 110 at the edge of the battery cell 100 is greater than the adhesion between the diaphragm 120 and the pole piece 110 in the middle of the battery cell 100. Therefore, the wettability of the middle of the pole piece 110 and the diaphragm 120 is improved, and the adhesion around the pole pieces 110 and between the pole pieces 110 and the diaphragm 120 is guaranteed. This ensures the service life of the battery cell 100 , improves the long-term fast charging capability, and improves the safety of the battery cell 100 .

[0049] It should be noted that the thickness direction of the battery cell 100 is as follows: Figure 1 Y direction shown.

[0050] It should be noted that wettability can be understood as the ability of the electrode 110 or the separator 120 to be wetted by the electrolyte when the battery cell 100 is in the electrolyte. Adhesion can be understood as the adhesion between the separator 120 and the electrode 110 or between the electrode 110.

[0051] For areas where there are large gaps between the pole pieces 110 (such as thinned areas and other locations), there is a risk of poor adhesion during long-term use of the battery 10, and accordingly the adhesion of the diaphragm 120 is increased in this area; for areas where the pole pieces 110 are difficult to wet (such as the center of the pole pieces 110 and other locations), there is a risk that the electrolyte is difficult to wet during long-term use of the battery 10, or cannot be fully wetted in a short period of time, and accordingly the wettability of the diaphragm 120 is increased in this area and in the path where the electrolyte diffuses to this area.

[0052] like Figures 2 to 8 As shown, in some embodiments, on the orthographic projection surface in the thickness direction of the battery cell 100, the battery cell 100 includes a first region a located in the middle of the battery cell 100 and a second region b located at the edge of the battery cell 100. The sum of the areas of the first coating 122 located in the second region b is greater than the sum of the areas of the first coating 122 located in the first region a. The sum of the areas of the second coating 123 located in the first region a is greater than the sum of the areas of the second coating 123 located in the second region b. In this way, the sum of the areas of the first coating 122 located in the second region b is greater than the sum of the areas of the first coating 122 located in the first region a. The adhesion of the second region b is greater than the adhesion of the second region b, that is, the adhesion of the region located at the edge of the battery cell 100 is greater than the adhesion of the region located in the middle of the battery cell 100, thereby improving the adhesion of the pole piece 110 at the edge of the battery cell 100. The sum of the areas of the second coating 123 located in the first region a is greater than the sum of the areas of the second coating 123 located in the second region b. The wettability of the first area a is greater than that of the second area b, that is, the wettability of the area in the middle of the battery cell 100 is greater than that of the area at the edge of the battery cell 100, thereby improving the wettability of the electrode 110 in the middle of the battery cell 100 and preventing the electrolyte from having difficulty in wetting the electrode 110 in the middle of the battery cell 100. This ensures the service life of the battery cell 100, improves the long-term fast charging capability, and improves the safety of the battery cell 100.

[0053] like Figure 2 As shown, in some embodiments, the first coating layer 122 and the second coating layer 123 are in strip shape, and the first coating layer 122 and the second coating layer 123 are arranged at intervals along the width direction of the base film 121, and the area of ​​the first coating layer 122 is smaller than the area of ​​the second coating layer 123. In this way, the first coating layer 122 and the second coating layer 123 in strip shape are arranged along the width direction of the base film 121, that is, along Figure 4 The first coating 122 is arranged in the Y direction. At least one side edge of the battery cell 100 is coated with the first coating 122, and the adhesion of the first coating 122 is greater than that of the second coating 123, thereby improving the adhesion of at least one side edge of the battery cell 100. The area of ​​the second coating 123 is greater than that of the first coating 122, so that the area of ​​the second coating 123 located in the middle of the battery cell 100 is larger, thereby improving the wettability of the middle of the battery cell 100. In addition, the coating layout method is simple and easy to produce.

[0054] like Figure 3As shown, in some embodiments, the first coating 122 and the second coating 123 are both in strip shape, and a plurality of first coatings 122 and a plurality of second coatings 123 are sequentially arranged at intervals along the length direction of the base film 121, and on the orthographic projection surface in the thickness direction of the battery cell 100, the first coating 122 is applied to both ends of the base film 121 along the length direction of the base film 121. In this way, by sequentially arranging a plurality of first coatings 122 and second coatings 123 in strip shape at intervals along the length direction of the base film 121, that is, along Figure 5 The coating on the base film 121 can be more evenly covered, thereby improving the reliability of the battery cell 100 after coating. In addition, on the orthographic projection surface in the thickness direction of the battery cell 100, the base film 121 is coated with the first coating 122 at both ends along its length direction, so that the edge of the base film 121 is coated with the first coating 122, thereby improving the adhesion of the edge of the battery cell 100. In this way, the service life of the battery cell 100 is guaranteed and the safety of the battery cell 100 is improved.

[0055] like Figure 4 As shown, in some embodiments, the first coating layer 122 is rectangular, and a plurality of first coating layers 122 are spaced apart along the length direction and the width direction of the base film 121, and the second coating layer 123 is applied between the plurality of first coating layers 122. In this way, by arranging the rectangular first coating layers 122 spaced apart along the length direction and the width direction of the base film 121, the uniformity of the coating layer distribution on the base film 121 is improved, thereby improving the reliability of the battery cell 100 after coating.

[0056] Furthermore, in one embodiment, on the orthographic projection surface in the thickness direction of the battery cell 100, the base film 121 is coated with the first coating 122 at both ends in the length direction and both ends in the width direction of the base film 121. In this way, it can be further ensured that the edge of the battery cell 100 is coated with the first coating 122, thereby increasing the adhesion of the edge of the battery cell 100. Thereby, the service life of the battery cell 100 and the safety of the battery cell 100 are improved.

[0057] like Figure 5As shown, in some embodiments, on the orthographic projection surface in the thickness direction of the battery cell 100, the battery cell 100 includes a first area a located in the middle of the battery cell 100 and a second area b located at the edge of the battery cell 100. The areas of the plurality of rectangular first coatings 122 are not equal, and the area of ​​the second coating 123 located in the first area a is greater than 1 / 2 of the area of ​​the first area a. In this way, by setting the areas between the plurality of rectangular first coatings 122 to be unequal, the first coating 122 of the corresponding area can be applied to the base film 121 according to actual conditions to meet different coating area requirements. In addition, the area of ​​the second coating 123 set in the first area a is greater than 1 / 2 of the area of ​​the first area a, so that the area of ​​the second coating 123 in the first area a is larger, thereby improving the wettability of the pole piece 110 and the diaphragm 120 in the middle of the battery cell 100. To improve the long-term fast charging capability of the battery cell 100.

[0058] like Figure 6 as well as Figure 7 As shown, in some embodiments, on the orthographic projection surface in the thickness direction of the battery cell 100, the battery cell 100 includes a first region a located in the middle of the battery cell 100 and a third region c located on the diagonal of the battery cell 100. The sum of the areas of the second coating 123 located in the first region a and the third region c is greater than 1 / 2 of the sum of the areas of the first region a and the third region c. In this way, by applying the second coating 123 to the first region a in the middle of the battery cell 100 and the third region c on the diagonal of the battery cell 100, the wettability of the middle region and the diagonal region of the battery cell 100 is improved to improve the long-term fast charging capability of the battery cell 100. In addition, the area of ​​the second coating 123 located in the first region a and the third region c is 1 / 2 of the sum of the areas of the first region a and the third region c, which further increases the area of ​​the second coating 123 located in the first region a and the third region c, thereby further improving the wettability of the pole piece 110 and the diaphragm 120 in the middle region and the diagonal region of the battery cell 100. Further improve the long-term fast charging capability of battery cell 100.

[0059] like Figure 8 As shown, in some embodiments, the first coating 122 is applied to at least a portion of the edge of the battery cell 100 avoiding the middle of the battery cell 100. In this way, by avoiding the middle of the battery cell 100 and applying the first coating 122 to at least a portion of the edge of the battery cell 100, the adhesion between the pole pieces 110 at the edge of the battery cell 100 or between the pole piece 110 and the separator 120 is improved, thereby improving the service life of the battery cell 100 and the safety of the battery cell 100.

[0060] like Figure 8As shown, in some embodiments, the second coating 123 is applied to at least a portion of the middle of the battery cell 100, avoiding the edge of the battery cell 100. In this way, by applying the first and second coatings 123 to at least a portion of the middle of the battery cell 100, avoiding the edge of the battery cell 100, the wettability of the electrode 110 and the separator 120 in the middle of the battery cell 100 is improved, so as to improve the long-term fast charging capability of the battery cell 100.

[0061] Furthermore, if Figure 8 As shown, in one embodiment, the first coating 122 is applied to the edge of the battery cell 100 avoiding the middle of the battery cell 100, and the second coating 123 is applied to the middle of the battery cell 100 avoiding the edge of the battery cell 100. In this way, the wettability of the electrode sheet 110 and the diaphragm 120 in the middle of the battery cell 100 is improved, and the adhesion between the electrode sheets 110 at the edge of the battery cell 100 and between the electrode sheets 110 and the diaphragm 120 is improved, thereby improving the service life of the battery cell 100, the long-term fast charging capability and the safety of the battery cell 100.

[0062] In some embodiments, Fig. 9 As shown, a vehicle 1 is provided, comprising a battery 10 according to any of the above embodiments, wherein the battery 10 applies a battery cell 100 according to any of the above embodiments, and can also improve the wettability of the pole piece 110 and ensure the adhesion of the pole piece 110, thereby improving the reliability of the vehicle 1 applying the battery 10.

[0063] It should be noted that the above embodiments can complement each other if there is no conflict.

[0064] The components included in the "component", "device" and "equipment" disclosed in the present invention can also be flexibly combined, that is, modular production can be carried out according to actual conditions and modular assembly can be carried out as an independent module; or they can be assembled separately to form a module in the present device.

[0065] The division of the above components in the present disclosure is only one of the embodiments, for the convenience of reading, rather than limiting the scope of protection of the present disclosure. As long as the above components are included and have the same function, it should be understood that they are equivalent technical solutions of the present disclosure. In the description of the present disclosure, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate the orientation or position relationship based on the orientation or position relationship shown in the accompanying drawings, only for the convenience of describing the present disclosure and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present disclosure.

[0066] In addition, the terms "first", "second", etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first", "second", etc. may explicitly or implicitly include at least one of the features. In the description of the present disclosure, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0067] In the present disclosure, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present disclosure can be understood according to specific circumstances.

[0068] In the present disclosure, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0069] It should be noted that when an element is referred to as being "fixed to", "disposed on", "fixedly arranged on" or "installed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. Furthermore, when an element is considered to be "fixedly connected to" another element, the two may be fixed in a detachable connection manner or in a non-detachable connection manner, such as socketing, snap-fitting, integral molding, welding, etc., which can be achieved in traditional technologies and will not be repeated here.

[0070] The technical features of the above embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0071] The above embodiments only express several implementation methods of the present disclosure, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the utility model patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the utility model concept of the present disclosure, and these all belong to the protection scope of the present disclosure.

Claims

1. A battery cell, characterized in that: include: Pole piece; A diaphragm, the diaphragm and the pole piece are stacked; the diaphragm comprises a base film, a first coating and a second coating, the adhesion of the first coating is greater than the adhesion of the second coating, and the wettability of the second coating is greater than the wettability of the first coating; At least one of the first coatings and at least one of the second coatings are respectively applied to the base film, so that on the orthographic projection surface in the thickness direction of the battery cell, the wettability of the electrode sheet in the middle of the battery cell is greater than the wettability of the electrode sheet at the edge of the battery cell, and the adhesion between the diaphragm and the electrode sheet at the edge of the battery cell is greater than the adhesion between the diaphragm and the electrode sheet in the middle of the battery cell.

2. The battery cell according to claim 1, characterized in that: On the orthographic projection surface in the thickness direction of the battery cell, the battery cell includes a first region located in the middle of the battery cell and a second region located at the edge of the battery cell; the sum of the areas of the first coating located in the second region is greater than the sum of the areas of the first coating located in the first region; the sum of the areas of the second coating located in the first region is greater than the sum of the areas of the second coating located in the second region.

3. The battery cell according to claim 1, characterized in that: The first coating layer and the second coating layer are in strip shape, the first coating layer and the second coating layer are spaced apart along the width direction of the base film, and the area of ​​the first coating layer is smaller than the area of ​​the second coating layer.

4. The battery cell according to claim 1, characterized in that: The first coating layer and the second coating layer are both in strip shape, and multiple first coating layers and multiple second coating layers are arranged in sequence along the length direction of the base film at intervals, and on the orthographic projection surface in the thickness direction of the battery cell, the first coating layer is applied to both ends of the base film along the length direction of the base film.

5. The battery cell according to claim 1, characterized in that: The first coating layer is rectangular in shape, and a plurality of the first coating layers are spaced apart along the length direction and the width direction of the base film, respectively, and the second coating layer is applied between the plurality of the first coating layers.

6. The battery cell according to claim 5, characterized in that: On the orthographic projection surface in the thickness direction of the battery cell, the battery cell includes a first region located in the middle of the battery cell and a second region located at the edge of the battery cell; the areas of the plurality of rectangular first coatings are not equal, and the sum of the areas of the second coatings located in the first regions is greater than 1 / 2 of the area of ​​the first regions.

7. The battery cell according to claim 1, characterized in that: On the orthographic projection plane in the thickness direction of the battery cell, the battery cell includes a first region located in the middle of the battery cell and a third region located on the diagonal of the battery cell; the sum of the areas of the second coating located in the first region and the third region is greater than 1 / 2 of the sum of the areas of the first region and the third region.

8. The battery cell according to claim 1, characterized in that: The first coating is applied to at least a portion of an edge of the battery cell, avoiding a middle portion of the battery cell.

9. The battery cell according to claim 1, characterized in that: The second coating is applied to at least a portion of a middle portion of the battery cell, avoiding edges of the battery cell.

10. A battery, characterized in that: It comprises a shell component and a battery cell as claimed in any one of claims 1 to 9, wherein the shell component is provided with a receiving cavity, the battery cell is arranged in the receiving cavity, and the receiving cavity is filled with an electrolyte.

11. A vehicle, characterized in that: Comprising the battery as claimed in claim 10.

Images