Battery and electric equipment

Abstract

The utility model relates to the field of lithium ion batteries, and discloses a battery and electric equipment, the battery comprises a battery cell and a membrane shell with a curved side wall, the battery cell comprises a diaphragm, and first pole pieces and second pole pieces which are alternately stacked in a first direction; in the second direction, the battery cell is provided with a first side and a second side which are opposite to each other, and at least on the first side of the battery cell, the first end part of the target first pole piece protrudes out of other first pole pieces and all second pole pieces; in the first direction, the target first pole piece is provided with a first surface and a second surface which are opposite to each other, and at least in the direction away from the first surface of the target first pole piece, the projections of the first end parts of other first pole pieces on the target first pole piece are sequentially away from the first end part of the target first pole piece; the first end part of the first pole piece is in contact with the side wall of the membrane shell; the projection of the second pole piece in the second direction is located in the projection range of the adjacent first pole piece in the second direction. The battery can be matched with the curved side wall of the battery compartment, so that the space utilization rate of the battery compartment is improved.

Description

Technical Field

[0001] This application relates to the field of lithium-ion batteries, and in particular to a battery and an electrical device. Background Technology

[0002] With the development of electronic products, curved structures have gradually emerged, and the sidewalls of the battery compartment near the curved edges are also curved. To better utilize the internal space of the battery compartment, wound cells can be used. However, because wound cells have arc segments on both sides in the width direction, stress cannot be released in the width direction when the cell expands, leading to problems such as compression deformation and breakage. Stacked cells, because they do not have arc segments on both sides in the width direction, can avoid deformation and breakage. However, stacked cells have other problems: the edges of stacked cells are right angles, which may not be suitable for battery compartments with curved sidewalls, or they may not fit snugly against the curved parts of the battery compartment, resulting in low space utilization and lower battery energy density.

[0003] Therefore, how to solve the above-mentioned technical problems should be a key focus for those skilled in the art. Utility Model Content

[0004] The purpose of this application is to provide a battery and an electrical device that adapts the battery to the curved sidewalls of the battery compartment, thereby improving the space utilization of the battery compartment and increasing the energy density of the battery.

[0005] To solve the above-mentioned technical problems, this application provides a battery, including: a battery cell and a membrane shell with curved sidewalls, wherein the battery cell includes a separator and a first electrode and a second electrode alternately stacked in a first direction, and the separator is located between the first electrode and the second electrode;

[0006] In the second direction, the cell has opposing first and second sides, and at least on the first side of the cell, the first end of the target first electrode protrudes beyond the first ends of the other first electrodes and the first ends of all the second electrodes; the target first electrode is one of the first electrodes.

[0007] In a first direction, the target first electrode has opposing first and second surfaces, and at least in a direction away from the first surface of the target first electrode, the projections of the first ends of other first electrodes on the target first electrode are sequentially away from the first ends of the target first electrode, and the second direction is perpendicular to the first direction;

[0008] The first end of the first electrode is in contact with the sidewall of the membrane shell;

[0009] The projection of the second pole piece in the second direction is located within the projection range of the adjacent first pole piece in the second direction.

[0010] Optionally, on the second side of the battery cell, the second ends of all the first pole pieces are flush, and the second ends of all the second pole pieces are flush.

[0011] On the second side of the battery cell, the second end of the target first pole piece protrudes from the second ends of the other first pole pieces and the second ends of all the second pole pieces; in the direction away from the first surface of the target first pole piece, the projections of the second ends of the other first pole pieces on the target first pole piece are sequentially away from the second end of the target first pole piece.

[0012] Optionally, the other first pole pieces and the second pole pieces are only located on one side of the first surface of the target first pole piece; or,

[0013] In the direction away from the second surface of the target first pole piece, the projections of the first ends of the other first pole pieces on the target first pole piece are sequentially away from the first end of the target first pole piece.

[0014] Optionally, when the projections of the first ends of the other first pole pieces on the target first pole piece are sequentially away from the first end of the target first pole piece, at least on the first side of the battery cell, the side surface of the battery cell is a semicircular surface, and the diameter of the semicircular surface is equal to the thickness of the battery cell in the first direction.

[0015] Optionally, at least on the first side of the battery cell, in the direction away from the first surface of the target first pole piece, the distances between the first ends of the other first pole pieces and / or the first ends of the second pole pieces and the first end of the target first pole piece in the second direction form an arithmetic sequence; and / or,

[0016] On the second side of the battery cell, when the second ends of all the first pole pieces are flush and the second ends of all the second pole pieces are flush, the distance between the second end of the second pole piece and the second end of the first pole piece in the second direction is d5, 0.5mm≤d5≤1mm; and / or,

[0017] On the first side of the battery cell and in the direction away from the first surface of the target first pole piece, the first angle between the line connecting the first end of the pole piece farthest from the target first pole piece and the first end of the target first pole piece and the first surface of the target first pole piece is α1, 35°≤α1≤75°; and / or,

[0018] In the first side of the battery cell, and in the direction away from the second surface of the target first tab, the second angle between the line connecting the first end of the tab farthest from the target first tab and the second surface of the target first tab is a2, 35°≤a2≤75°; and / or,

[0019] In the second side of the battery cell, and in the direction away from the first surface of the target first tab, the third angle between the line connecting the second end of the tab farthest from the target first tab and the first end of the target first tab and the first surface of the target first tab is a3, 35°≤a3≤75°;

[0020] In the second side of the battery cell, and in the direction away from the second surface of the target first tab, the fourth angle between the line connecting the second end of the tab farthest from the target first tab and the second end of the target first tab and the second surface of the target first tab is a4, 35°≤a4≤75°.

[0021] Optionally, the first angle and the second angle are equal in size; and / or,

[0022] The third angle and the fourth angle are equal in size.

[0023] Optionally, in the first direction, when the tab farthest from the target first tab is a negative tab, the separator is distributed on the side of the negative tab away from the target first tab; and / or,

[0024] The active material layer of the first tab comprises a silicon-based active material layer.

[0025] Optionally, the lengths of all the separators in the second direction are equal, and the length of the separator is greater than the length of the target first tab in the second direction; or,

[0026] The length of the separator in the second direction is greater than the length of the adjacent first tab in the second direction, and the lengths of the separators in the second direction are not completely equal.

[0027] Optionally, when the lengths of all the separators in the second direction are equal, in the first side of the battery cell, the distance between the first end of the separator and the first end of the target first tab in the second direction is d6, 0.5mm≤d6≤1mm; and / or,

[0028] When the lengths of all the separators in the second direction are equal, in the second side of the battery cell, the distance between the second end of the separator and the second end of the target first tab in the second direction is d7, 0.5mm≤d7≤1mm; and / or,

[0029] When the length of the separator in the second direction is greater than the length of the adjacent first tab in the second direction, and the length of each separator in the second direction is not completely equal, on the first side of the battery cell, the distance between the first end of the separator and the first end of the adjacent first tab in the second direction is d6, 0.5mm≤d6≤1mm; and / or,

[0030] When the length of the separator in the second direction is greater than the length of the adjacent first tab in the second direction, and the length of each separator in the second direction is not completely equal, on the second side of the battery cell, the distance between the second end of the separator and the second end of the adjacent first tab in the second direction is d7, 0.5mm≤d7≤1mm.

[0031] The application also provides a battery using device.

[0032] The application provides a battery, comprising: a battery cell and a film shell with a curved side wall, the battery cell comprises a separator and first and second tabs alternately stacked in a first direction, the separator is located between the first and second tabs; in a second direction, the battery cell has opposite first and second sides, and at least on the first side of the battery cell, the first end of a target first tab protrudes from the first ends of other first tabs and the first ends of all second tabs; the target first tab is one of the first tabs; in the first direction, the target first tab has opposite first and second surfaces, and at least in the direction away from the first surface of the target first tab, the projections of the first ends of other first tabs on the target first tab successively move away from the first end of the target first tab, and the second direction is perpendicular to the first direction; the first end of the first tab is in contact with the side wall of the film shell; the projection of the second tab in the second direction is located within the projection range of the adjacent first tab in the second direction.

[0033] It can be seen that the battery cell in the battery of the application is a laminated battery cell, at least on the first side of the battery cell, the first end of the target first tab protrudes from the first ends of other tabs, and since the projections of the first ends of the first tabs successively stacked on the first surface of the target first tab successively move away from the first end of the target first tab, the first end of the first tab is in contact with the side wall of the film shell, and since the projection of the second tab in the second direction is within the projection range of the adjacent first tab, the first end of the second tab on the first side does not affect the shape of the first end of the first tab, i.e. the battery of the application can be matched and fitted with a battery compartment with a curved side wall, improving the space utilization of the battery compartment and the energy density of the battery.

[0034] In addition, the application also provides a battery using device with the above advantages. Attached Figure Description

[0035] To more clearly illustrate the technical solutions of the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0036] Figure 1 A top view of a battery cell provided in an embodiment of this application;

[0037] Figure 2 The following are provided for the embodiments of this application: Figure 1 Schematic diagram of the cell cross section of section AA Figure 1 ;

[0038] Figure 3 The following are provided for the embodiments of this application: Figure 1 Schematic diagram of the cell cross section of section AA Figure 2 ;

[0039] Figure 4 for Figure 2 and Figure 3 The diagram shows the distribution of battery compartments in electronic products to which the battery cells can be used.

[0040] Figure 5 The following are provided for the embodiments of this application: Figure 1 Schematic diagram of the cell cross section of section AA Figure 3 ;

[0041] Figure 6 The following are provided for the embodiments of this application: Figure 1 Schematic diagram of the cell cross section of section AA Figure 4 ;

[0042] Figure 7 for Figure 5 and Figure 6 The diagram shows the distribution of battery compartments in electronic products to which the battery cells can be applied. Figure 1 ;

[0043] Figure 8 for Figure 5 and Figure 6 The diagram shows the distribution of battery compartments in electronic products to which the battery cells can be applied. Figure 2 ;

[0044] Figure 9 This is a schematic diagram illustrating the positional relationship between a target first electrode and other first electrodes provided in an embodiment of this application.

[0045] Figure 10This is a schematic diagram illustrating the positional relationship between the first and second target electrodes provided in an embodiment of this application.

[0046] Figure 11 This is a schematic diagram showing the angle between the outermost electrode of the battery cell and the first electrode of the target.

[0047] Figure 12 This is a schematic diagram of the outermost arrangement of a battery cell provided in an embodiment of this application. Figure 1 ;

[0048] Figure 13 This is a schematic diagram of the outermost arrangement of a battery cell provided in an embodiment of this application. Figure 2 ;

[0049] Figure 14 This is a schematic diagram of the distribution of the diaphragm provided in the embodiments of this application. Figure 1 ;

[0050] Figure 15 This is a schematic diagram of the distribution of the diaphragm provided in the embodiments of this application. Figure 2 ;

[0051] In the diagram, 1 is the first electrode, 2 is the second electrode, 3 is the separator, 4 is the positive electrode tab, 5 is the negative electrode tab, 100 is the electronic product, and 101 is the battery compartment. Detailed Implementation

[0052] To enable those skilled in the art to better understand the present application, the present application will be further described in detail below with reference to the accompanying drawings and specific embodiments. Obviously, the described embodiments are merely some embodiments of the present application, and not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0053] Many specific details are set forth in the following description in order to provide a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Those skilled in the art can make similar extensions without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0054] As described in the background section, the edges of current stacked battery cells are right angles, which may not be suitable for battery compartments with curved sidewalls, or may not fit snugly with the curved part of the battery compartment, resulting in low space utilization of the battery compartment and relatively low energy density of the battery.

[0055] In view of this, this application provides a battery, please refer to... Figures 1-2 , Figure 14 and Figure 15The battery can include an electrode core and a film casing having a curved side wall, the electrode core can include:

[0056] a separator 3 and first and second pole pieces 1 and 2 alternately stacked in a first direction Z, the separator 3 being located between the first and second pole pieces 1 and 2;

[0057] In a second direction Y, the electrode core has opposite first and second sides C1 and C2, and at least on the first side C1 of the electrode core, a first end portion of a target first pole piece 1 protrudes from first end portions of other first pole pieces 1 and first end portions of all second pole pieces 2; the target first pole piece 1 is one of the first pole pieces 1;

[0058] In the first direction Z, the target first pole piece 1 has opposite first and second surfaces S1 and S2, and in at least a direction away from the first surface S1 of the target first pole piece 1, projections of the first end portions of the other first pole pieces 1 on the target first pole piece 1 are sequentially away from the first end portion of the target first pole piece 1, the second direction Y being perpendicular to the first direction Z;

[0059] The first end portion of the first pole piece is in contact with the side wall of the film casing;

[0060] A projection of the second pole piece 2 in the second direction is located within a projection range of an adjacent first pole piece 1 in the second direction.

[0061] It should be noted that the battery further includes a positive tab 4 and a negative tab 5, the positive tab 4 being electrically connected to the positive pole piece, and the negative tab 5 being electrically connected to the negative pole piece.

[0062] The electrode core is located in the film casing, and the film casing can be an aluminum plastic film or the like.

[0063] The first direction Z is a thickness direction of the electrode core, the second direction Y is a width direction of the electrode core, and the third direction X is a length direction of the electrode core.

[0064] The first pole piece 1 can be a negative pole piece, and the second pole piece 2 can be a positive pole piece. The negative pole piece includes a negative current collector and a negative active material layer located on a surface of the negative current collector. When the negative pole piece has a positive pole piece on both sides in the first direction Z, both surfaces of the negative current collector opposite in the first direction Z are distributed with the negative active material layer. When the negative pole piece has a positive pole piece on only one side in the first direction Z, the surface of the negative current collector opposite the positive pole piece is distributed with the negative active material layer, and the other surface is not distributed with the negative active material layer.

[0065] In this embodiment, the material of the active material layer of the first pole piece 1 is not limited, for example, it can be a carbon material or a non-carbon material, etc. Among them, the carbon material includes but is not limited to graphite, soft carbon material, and hard carbon material.

[0066] In one possible implementation, the active material layer of the first electrode 1 includes a silicon-based active material layer. The silicon-based active material layer contains silicon-based materials, and the specific capacity of the silicon-based materials is greater than that of the graphite materials, which can improve the energy density of the battery.

[0067] The ratio of the mass of silicon-based material to the total weight of the silicon-based active material layer can range from 5% to 35%.

[0068] Silicon-based materials include, but are not limited to, any one or any combination of elemental silicon, silicon-carbon, silicon oxide compounds, lithium-silicon compounds, and silicon alloys. Among them, silicon-carbon is a porous carbon-deposited silicon material, comprising a framework, which includes a porous carbon framework body and silicon material. The porous carbon framework body has pores, and the silicon material fills at least a portion of the pores in the porous carbon framework body.

[0069] The positive electrode includes a positive current collector and a positive active material layer on the surface of the positive current collector. When there are negative electrodes on both sides of the positive electrode in the first direction Z, the positive active material layer is distributed on both opposite surfaces of the positive current collector in the first direction Z. When there is only one negative electrode on one side of the positive electrode in the first direction Z, the positive active material layer is distributed on the surface of the positive current collector opposite to the negative electrode, and the other surface does not have a positive active material layer.

[0070] The thickness of the negative electrode active material layer on the surface of the negative electrode current collector can be set according to actual conditions, and is not limited in this embodiment. As one possible implementation, the thickness of the negative electrode active material layer on the surface of the negative electrode current collector can range from 20μm to 75μm. For example, the thickness of the negative electrode active material layer on the surface of the negative electrode current collector can be 20μm, 40μm, 60μm, 70μm, 75μm, etc.

[0071] The thickness of the positive electrode active material layer on the surface of the positive electrode current collector can be set according to actual conditions, and is not limited in this embodiment. As one possible implementation, the thickness of the positive electrode active material layer on the surface of the positive electrode current collector can be in the range of 25μm~60μm. For example, the thickness of the positive electrode active material layer on the surface of the positive electrode current collector can be 25μm, 35μm, 45μm, 55μm, 60μm, etc.

[0072] The thickness of the diaphragm 3 can range from 4μm to 20μm. For example, the thickness of the diaphragm 3 can be 4μm, 8μm, 12μm, 16μm, 20μm, etc.

[0073] like Figure 1 As shown, of the two sides of the battery cell, C1 is on the left and C2 is on the right.

[0074] The length of the target first pole piece 1 in the second direction Y is the longest among all the pole pieces.

[0075] In the direction away from the first surface S1 of the target first pole piece 1, the first pole pieces 1 stacked in sequence can be called the first first pole piece 1, the second first pole piece 1, …, the Mth first pole piece 1 in sequence, and the projections of the first end of the first first pole piece 1, the second first pole piece 1, …, the Mth first pole piece 1 on the target first pole piece 1 are away from the first end of the target first pole piece 1 in sequence, that is, the projections of the first end of the first first pole piece 1, the second first pole piece 1, …, the Mth first pole piece 1 on the target first pole piece 1 are arranged in the direction in which the second side C2 is located in sequence. The first end of the first pole piece is in contact with the side wall of the film shell.

[0076] The projection of the second pole piece 2 in the second direction is located in the projection range of the adjacent first pole piece 1 in the second direction, that is, the length of the second pole piece 2 in the second direction Y is less than the length of the adjacent first pole piece 1 in the second direction Y, that is, the first end of the second pole piece 2 is located on the side of the first end of the adjacent first pole piece 1 close to the second side C2. On the one hand, it can be ensured that the first pole piece 1 matches and fits the battery compartment with a curved side wall, and on the other hand, it can be ensured that the second pole piece 2 is completely covered by the first pole piece 1, so as to avoid the problem of electrolysis caused by poor coverage of the first pole piece 1 to the second pole piece 2 and improve the service life of the battery.

[0077] It should be noted that the distribution of the second side C2 of the battery cell, the second end of the first pole piece 1 and the second end of the second pole piece 2 in the embodiment is not limited, and will be described in the following embodiments.

[0078] As an implementable manner, the side where the second surface S2 of the target first pole piece 1 is located can have no stacking of the first pole piece 1 and the second pole piece 2, as shown in Figure 1 At this time, on the side where the first surface S1 of the target first pole piece 1 is located in the first direction Z, the outermost pole piece can be the first pole piece 1 or the second pole piece 2, which is not limited in the present application.

[0079] As other implementations, the side where the second surface S2 of the target first pole piece 1 is located can also have stacking of the first pole piece 1 and the second pole piece 2, which will be described in the following embodiments. At this time, on the side where the first surface S1 of the target first pole piece 1 is located and on the side where the second surface S2 of the target first pole piece 1 is located in the first direction Z, the outermost pole piece can be the first pole piece 1 or the second pole piece 2, which is not limited in the present application.

[0080] The electric cell in the battery of the embodiment is a laminated electric cell. At least on the first side C1 of the electric cell, the first end of the target first pole piece 1 protrudes from the first end of the other pole pieces. Since the projections of the first end of the first pole pieces 1 on the target first pole piece 1 in sequence are away from the first end of the target first pole piece 1 at least on the first surface S1 of the target first pole piece 1, the first end of the first pole piece is in contact with the side wall of the film shell. Therefore, at least on the first side C1 of the electric cell and above the first surface S1 of the target first pole piece 1, the first pole piece 1 can be matched with the battery compartment with a curved side wall. Since the projection of the second pole piece 2 in the second direction is within the projection range of the adjacent first pole piece 1, the first end of the second pole piece 2 on the first side C1 does not affect the shape of the first end of the first pole piece 1, thereby making the battery of the embodiment matched with the battery compartment with a curved side wall, improving the space utilization of the battery compartment, and the energy density of the battery.

[0081] As shown in Figures 2-3 , on the basis of the above embodiment, in one embodiment of the present application, on the second side C2 of the electric cell, the second ends of all the first pole pieces 1 are flush, and the second ends of all the second pole pieces 2 are flush.

[0082] The electric cell in the embodiment has an arc-shaped curved surface on the first side C1 and a flat surface on the second side C2. The electric cell can be applied to a battery compartment with an arc-shaped curved surface on one side and a flat surface on the other side. At this time, the position of the battery compartment 101 in the electronic product 100 is as shown in Figure 4 , the arc-shaped curved surface of the battery compartment is matched with the arc-shaped surface of the electronic product, and the flat surface of the battery compartment is located on the inner side of the electronic product.

[0083] It should be pointed out that in the embodiment, whether the second surface S2 of the target first pole piece 1 is distributed with the first pole pieces 1 and the second pole pieces 2 is not limited, and is determined according to the situation.

[0084] As an implementable manner, as shown in Figure 2 , the other first pole pieces 1 and the second pole pieces 2 are located on the side of the first surface S1 of the target first pole piece 1. That is, the second surface S2 of the target first pole piece 1 is not stacked with other pole pieces. The curved surface formed on the first side C1 of the electric cell can be a quarter spherical surface.

[0085] As another implementable manner, as shown in Figure 3 , in the direction away from the second surface S2 of the target first pole piece 1, the projections of the first end of the other first pole pieces 1 on the target first pole piece 1 are away from the first end of the target first pole piece 1 in sequence.

[0086] The first surface S1 and the second surface S2 of the target first electrode 1 are both stacked with the first electrode 1 and the second electrode 2.

[0087] In the direction away from the second surface S2 of the target first electrode 1, the first electrodes 1 stacked sequentially can be referred to as the first first electrode 1, the second first electrode 1, ..., the Nth first electrode 1. The projections of the first ends of the first first electrode 1, the second first electrode 1, ..., the Nth first electrode 1 onto the target first electrode 1 are sequentially farther away from the first end of the target first electrode 1. That is, the projections of the first ends of the first first electrode 1, the second first electrode 1, ..., the Nth first electrode 1 onto the target first electrode 1 are sequentially arranged in the direction of the second side C2. M and N can be equal or unequal, both within the scope of protection of this application.

[0088] like Figures 5-6 As shown, based on the above embodiments, in one embodiment of this application, on the second side C2 of the battery cell, the second end of the target first electrode 1 protrudes beyond the second ends of the other first electrodes 1 and the second ends of all the second electrodes 2; in the direction away from the first surface S1 of the target first electrode 1, the projections of the second ends of the other first electrodes 1 onto the target first electrode 1 are sequentially away from the second ends of the target first electrode 1.

[0089] In the direction away from the second surface S2 of the target first electrode 1, the projections of the second ends of the first first electrode 1, the second first electrode 1, ..., the Mth first electrode 1 onto the target first electrode 1 are sequentially moved away from the second end of the target first electrode 1, that is, the projections of the second ends of the first first electrode 1, the second first electrode 1, ..., the Mth first electrode 1 onto the target first electrode 1 are sequentially arranged in the direction of the first side C1. The second end of the first electrode is in contact with the sidewall of the membrane shell. Therefore, the battery cell of this embodiment has an arc-shaped curved surface on both the first side C1 and the second side C2. This battery cell can be applied to a battery compartment with arc-shaped curved surfaces on both sides. In this case, the position of the battery compartment 101 in the electronic product 100 is as follows: Figure 7 and Figure 8 As shown, one arc-shaped surface of the battery compartment 101 is in contact with the arc-shaped surface of the electronic product 100, and the other arc-shaped surface is located inside the electronic product 100. Alternatively, both arc-shaped surfaces of the battery compartment 101 are in contact with the arc-shaped surface of the electronic product 100.

[0090] It should be noted that in this embodiment, there is no limitation on whether the second surface S2 of the target first electrode 1 is distributed with the first electrode 1 and the second electrode 2, depending on the situation.

[0091] As one possible implementation method, such as Figure 5As shown, other first pole pieces 1 and second pole pieces 2 are only located on the side of the first surface S1 of the target first pole piece 1. That is, the second surface S2 of the target first pole piece 1 is not stacked with other pole pieces. The curved surface formed on the first side C1 and the second side C2 of the battery cell can be a quarter spherical surface respectively.

[0092] As another implementation, as shown in FIG. 1C, in the direction away from the second surface S2 of the target first pole piece 1, the projections of the first end of other first pole pieces 1 on the target first pole piece 1 are sequentially away from the first end of the target first pole piece 1. Figure 6

[0093] The first surface S1 and the second surface S2 of the target first pole piece 1 are both stacked with first pole pieces 1 and second pole pieces 2.

[0094] In the direction away from the second surface S2 of the target first pole piece 1, the sequentially stacked first pole pieces 1 can be sequentially referred to as the first first pole piece 1, the second first pole piece 1, …, the Nth first pole piece 1. The projections of the first end of the first first pole piece 1, the second first pole piece 1, …, the Nth first pole piece 1 on the target first pole piece 1 are sequentially away from the first end of the target first pole piece 1, that is, the projections of the first end of the first first pole piece 1, the second first pole piece 1, …, the Nth first pole piece 1 on the target first pole piece 1 are sequentially arranged in the direction of the second side C2. Wherein, M and N can be equal or not equal, both within the protection scope of the present application.

[0095] Please refer to Figure 6 On the basis of any of the above embodiments, in an embodiment of the present application, at least on the first side C1 of the battery cell, the side surface of the battery cell is a semicircular curved surface, and the diameter d of the semicircular curved surface is equal to the thickness H of the battery cell in the first direction Z.

[0096] The thickness H of the battery cell in the first direction Z is the distance between the two outermost pole pieces in the first direction Z.

[0097] The thickness H of the battery cell can range from 3mm to 7mm. For example, the thickness H of the battery cell can be 3mm, 4mm, 5mm, 6mm, 7mm, etc.

[0098] Please refer to Figure 6 On the first side C1 of the battery cell, the first end of the two outermost pole pieces and the first end of the target first pole piece 1 in the first direction Z can form a semicircular curved surface, and the diameter d of the semicircular curved surface is the distance between the first ends of the two outermost pole pieces in the first direction Z.

[0099] Please refer to Figure 6 ​On the second side C2 of the battery cell, the second end of the two outermost electrode pieces and the second end of the target first electrode piece 1 in the first direction Z can form a semicircular surface, and the diameter d of the semicircular surface is the distance between the first ends of the two outermost electrode pieces in the first direction Z.

[0100] The diameter d of the semicircular surface on the side of the battery cell is equal to the thickness H of the battery cell, which can better match the curved surface of the battery compartment.

[0101] In an embodiment of the present application, at least on the first side C1 of the battery cell, the distance between the first end of the other first electrode piece 1 and the first end of the target first electrode piece 1 in the second direction Y forms an arithmetic sequence in the direction away from the first surface S1 of the target first electrode piece 1, so as to form a smooth curve on the first side C1 and better match the curved side wall of the battery compartment, thereby improving the space utilization of the battery compartment.

[0102] It should be noted that the distance between the first end of the first first electrode piece 1 and the first end of the target first electrode piece 1 in the second direction Y is not limited in the embodiment. For example, please refer to Figure 9 The distance d1 between the first end of the first first electrode piece 1 and the first end of the target first electrode piece 1 in the second direction Y can range from 0.1 mm to 0.7 mm. For example, the distance d1 between the first end of the first first electrode piece 1 and the first end of the target first electrode piece 1 in the second direction Y can be 0.1 mm, 0.3 mm, 0.5 mm, 0.7 mm, etc.

[0103] It should be noted that the common difference of the arithmetic sequence is not limited in the embodiment, and can be determined as appropriate. For example, the common difference of the arithmetic sequence can be 0.3 mm. Accordingly, the distance d2 between the first end of the second first electrode piece 1 and the first end of the target first electrode piece 1 in the second direction Y can range from 0.4 mm to 1.1 mm; the distance between the first end of the third first electrode piece 1 and the first end of the target first electrode piece 1 in the second direction Y can range from 0.7 mm to 1.4 mm, and so on.

[0104] It can be understood that when the first side C1 of the battery cell, when the target first tab 1 is also distributed on the second surface S2 of the first tab 1 and the second tab 2, in the direction away from the second surface S2 of the target first tab 1, the distance between the first end of the other first tab 1 and the first end of the target first tab 1 in the second direction Y can also be an arithmetic sequence. When the second side C2 of the battery cell is also an arc-shaped surface, in the direction away from the first surface S1 of the target first tab 1, the distance between the second end of the other first tab 1 and the second end of the target first tab 1 in the second direction Y can also be an arithmetic sequence; in the direction away from the second surface S2 of the target first tab 1, the distance between the second end of the other first tab 1 and the second end of the target first tab 1 in the second direction Y can also be an arithmetic sequence.

[0105] In an embodiment of the present application, at least on the first side C1 of the battery cell, in the direction away from the first surface S1 of the target first tab 1, the distance between the first end of the second tab 2 and the first end of the target first tab 1 in the second direction Y is an arithmetic sequence, which is well adapted to the length of the first tab 1, ensuring that the projection of the second tab 2 in the second direction is within the projection range of the first tab 1 in the second direction.

[0106] It should be noted that the distance between the first end of the first second tab 2 and the first end of the target first tab 1 in the second direction Y is not limited in the present embodiment. For example, please refer to Figure 10 , the distance between the first end of the first second tab 2 and the first end of the target first tab 1 in the second direction Y is d3, 0.3mm≤d3≤1.0mm. For example, the distance d3 between the first end of the first second tab 2 and the first end of the target first tab 1 in the second direction Y can be 0.3mm, 0.5mm, 0.7mm, 1.0mm, etc.

[0107] It should be noted that the tolerance of the arithmetic sequence is not limited in the present embodiment, which is determined according to the situation. For example, the tolerance of the arithmetic sequence can be 0.3mm. Correspondingly, the distance between the first end of the second second tab 2 and the first end of the target first tab 1 in the second direction Y is d4, 0.6mm≤d4≤1.3mm; the distance between the first end of the third second tab 2 and the first end of the target first tab 1 in the second direction Y can be 0.9mm~1.7mm, and so on.

[0108] It can be understood that when the first side C1 of the battery cell, when the target first tab 1 is also distributed on the second surface S2 of the first tab 1 and the second tab 2, in the direction away from the second surface S2 of the target first tab 1, the distance between the first end of the second tab 2 and the first end of the target first tab 1 in the second direction Y can also be an arithmetic progression. When the second side C2 of the battery cell is also an arc-shaped surface, in the direction away from the first surface S1 of the target first tab 1, the distance between the second end of the second tab 2 and the second end of the target first tab 1 in the second direction Y can also be an arithmetic progression; in the direction away from the second surface S2 of the target first tab 1, the distance between the second end of the second tab 2 and the second end of the target first tab 1 in the second direction Y can also be an arithmetic progression.

[0109] On the basis of any of the above embodiments, in an embodiment of the present application, please refer to Figure 2 and Figure 3 On the second side C2 of the battery cell, when all the second ends of the first tab 1 are flush, all the second ends of the second tab 2 are flush, the distance between the second end of the second tab 2 and the second end of the first tab 1 in the second direction Y is d5, 0.5mm≤d5≤1mm, to ensure that the projection of the second tab 2 in the second direction falls within the projection range of the first tab 1, and avoid the problem of lithium precipitation caused by the second tab 2 not being effectively covered by the first tab 1.

[0110] For example, the distance d5 between the second end of the second tab 2 and the second end of the first tab 1 in the second direction Y can be 0.5mm, 0.7mm, 0.9mm, 1mm, etc.

[0111] Please refer to Figure 11 In an embodiment of the present application, on the first side C1 of the battery cell, and in the direction away from the first surface S1 of the target first tab 1, the first angle between the line connecting the first end of the tab farthest from the target first tab 1 and the first end of the target first tab 1 and the first surface S1 of the target first tab 1 is α1, 35°≤α1≤75°.

[0112] For example, the size of the first angle α1 can be 35°, 45°, 45°, 65°, 75°, etc.

[0113] The tab farthest from the first surface S1 of the target first tab 1, i.e. the outermost tab in the first direction Z, can be a first tab 1 or a second tab 2.

[0114] By setting the first included angle a1 to be 35°-75°, the upper portion of the first surface S1 of the first side C1 of the battery cell and the target first tab 1 can better match the curved side wall of the battery compartment.

[0115] For reference Figure 11 In one embodiment of the present application, on the basis of the above-mentioned embodiments, the second included angle a2 between the line connecting the first end of the tab farthest from the target first tab 1 and the first end of the target first tab 1 and the second surface S2 of the target first tab 1 is 35°-75° on the first side C1 of the battery cell and in the direction away from the second surface S2 of the target first tab 1.

[0116] For example, the second included angle a2 can be 35°, 45°, 45°, 65°, 75°, etc.

[0117] The tab farthest from the second surface S2 of the target first tab 1, i.e., the outermost tab in the first direction Z, can be the first tab 1 or the second tab 2.

[0118] By setting the second included angle a2 to be 35°-75°, the arc-shaped surface of the first side C1 of the battery cell can better match the curved side wall of the battery compartment.

[0119] In the present embodiment, the relationship between the first included angle a1 and the second included angle a2 is not limited, and is determined according to the situation. As one implementation manner, the first included angle a1 and the second included angle a2 can be different in size. As another implementation manner, the first included angle a1 and the second included angle a2 can be equal in size, which can simplify the manufacturing process of the battery cell.

[0120] For reference Figure 11 In one embodiment of the present application, on the basis of the above-mentioned embodiments, the third included angle a3 between the line connecting the second end of the tab farthest from the target first tab 1 and the second end of the target first tab 1 and the first surface S1 of the target first tab 1 is 35°-75° on the second side C2 of the battery cell and in the direction away from the first surface S1 of the target first tab 1.

[0121] For example, the third included angle a3 can be 35°, 45°, 45°, 65°, 75°, etc.

[0122] By setting the third included angle a3 to be 35°-75°, the arc-shaped surface of the first side C1 of the battery cell can better match the curved side wall of the battery compartment, improving the space utilization of the battery compartment.

[0123] For reference Figure 11In an embodiment of the present application, on the second side C2 of the battery cell, and in the direction away from the second surface S2 of the target first tab 1, the fourth included angle between the line connecting the second end of the tab farthest from the target first tab 1 and the second surface S2 of the target first tab 1 is α4, and 35°≤α4≤75°.

[0124] For example, the fourth included angle α4 can be 35°, 45°, 45°, 65°, 75°, etc.

[0125] By setting the fourth included angle α4 to be between 35° and 75°, the arc-shaped surface on the second side C2 of the battery cell can better match the curved side wall of the battery compartment, thereby improving the space utilization of the battery compartment.

[0126] The size relationship between the third included angle α3 and the fourth included angle α4 is not limited in the present embodiment and can be determined as appropriate. As one possible implementation, the third included angle α3 and the fourth included angle α4 can be different in size. As another possible implementation, the third included angle α3 and the fourth included angle α4 can be equal in size, which can simplify the manufacturing process of the battery cell.

[0127] For reference Figure 12 In an embodiment of any of the above embodiments, in the first direction Z, when the tab farthest from the target first tab 1 is a negative tab, the separator 3 is arranged on the side of the negative tab away from the target first tab 1.

[0128] The tab farthest from the target first tab 1, i.e., the outermost tab on the side of the target first tab 1 in the first direction Z; or, the outermost tab on the side of the target first tab 1 in the first direction Z and on the side of the second surface S2 of the target first tab 1.

[0129] Since the negative tab farthest from the target first tab 1 has no positive tab on the side away from the target first tab 1, the negative tab farthest from the target first tab 1 has no negative active material layer on the side away from the target first tab 1, i.e., the negative current collector is directly exposed. Since the negative current collector is generally a copper foil, when the shell of the battery is an aluminum plastic film, a side reaction can occur between the copper foil and the aluminum plastic film. By arranging the separator 3 on the outermost side in the first direction Z, the present embodiment can prevent the occurrence of the side reaction between the copper foil and the aluminum plastic film, thereby preventing the corrosion of the aluminum plastic film.

[0130] In an embodiment of the present application, in the first direction Z, when the tab farthest from the target first tab 1 is a positive tab, the separator 3 can be arranged on the side of the positive tab away from the target first tab 1, or the separator 3 can not be arranged, as shown inFigure 13 As shown, the positive electrode tab farthest from the target first electrode tab 1 has no positive active material layer on the side away from the target first electrode tab 1, i.e., the positive current collector is directly exposed.

[0131] As shown, on the basis of any of the above embodiments, in an embodiment of the present application, the lengths of all the separators 3 in the second direction Y are equal, and the length of the separator 3 is greater than the length of the target first electrode tab 1 in the second direction Y. Figure 14 In the first direction Z, since the lengths of the other first electrode tabs 1 away from the target first electrode tab 1 gradually decrease, the length of the separator 3 beyond the first electrode tab 1 gradually increases on the first side C1 of the battery cell, or on the first side C1 and the second side C2 of the battery cell. Since the material of the separator 3 is relatively soft, the separator 3 can be stacked on the first side C1 of the battery cell, or on the first side C1 and the second side C2 of the battery cell, and can absorb more electrolyte, thereby avoiding edge precipitation.

[0132] As an implementable manner, when the lengths of all the separators 3 in the second direction Y are equal, the distance between the first end of the separator 3 and the first end of the target first electrode tab 1 in the second direction Y on the first side C1 of the battery cell is d6, 0.5mm≤d6≤1mm. On the one hand, this can ensure that the separator 3 can effectively cover the active material layer on the first electrode tab 1, thereby avoiding short circuit problems. On the other hand, this can also avoid excessive use of the separator 3, thereby reducing costs. At the same time, this can also simplify the manufacturing process.

[0133] For example, the distance between the first end of the separator 3 and the first end of the target first electrode tab 1 in the second direction Y can be 0.5mm, 0.7mm, 0.9mm, 1mm, etc.

[0134] As another implementable manner, when the lengths of all the separators 3 in the second direction Y are equal, the distance between the second end of the separator 3 and the second end of the target first electrode tab 1 in the second direction Y on the second side C2 of the battery cell is d7, 0.5mm≤d7≤1mm. On the one hand, this can ensure that the separator 3 can effectively cover the active material layer on the first electrode tab 1, thereby avoiding short circuit problems. On the other hand, this can also simplify the manufacturing process.

[0135] For example, the distance between the second end of the separator 3 and the second end of the target first electrode tab 1 in the second direction Y can be 0.5mm, 0.7mm, 0.9mm, 1mm, etc.

[0136] As shown, on the basis of any of the above embodiments, in an embodiment of the present application, the lengths of all the separators 3 in the second direction Y are equal, and the length of the separator 3 is greater than the length of the target first electrode tab 1 in the second direction Y.

[0137] Figure 15 ​As shown, on the basis of any of the above embodiments, in an embodiment of the present application, the length of the separator 3 in the second direction Y is greater than the length of the adjacent first pole piece 1 in the second direction Y, and the length of each separator 3 in the second direction Y is not completely equal, so as to reduce the amount of the separator 3 and reduce the cost.

[0138] As an implementable manner, when the length of the separator 3 in the second direction Y is greater than the length of the adjacent first pole piece 1 in the second direction Y, and the length of each separator 3 in the second direction Y is not completely equal, the distance between the first end of the separator 3 and the first end of the adjacent first pole piece 1 in the second direction Y on the first side C1 of the battery cell is d6, 0.5mm≤d6≤1mm, so as to ensure that the separator 3 can effectively cover the active material layer on the first pole piece 1 and avoid short circuit problems.

[0139] For example, the distance d6 between the first end of the separator 3 and the first end of the target first pole piece 1 in the second direction Y can be 0.5mm, 0.7mm, 0.9mm, 1mm, etc.

[0140] As an implementable manner, when the length of the separator 3 in the second direction Y is greater than the length of the adjacent first pole piece 1 in the second direction Y, and the length of each separator 3 in the second direction Y is not completely equal, the distance between the second end of the separator 3 and the second end of the adjacent first pole piece 1 in the second direction Y on the second side C2 of the battery cell is d7, 0.5mm≤d7≤1mm, so as to ensure that the separator 3 can effectively cover the active material layer on the first pole piece 1 and avoid short circuit problems.

[0141] For example, the distance d7 between the second end of the separator 3 and the second end of the target first pole piece 1 in the second direction Y can be 0.5mm, 0.7mm, 0.9mm, 1mm, etc.

[0142] The present application also provides a battery for an electric device.

[0143] The electric device includes but is not limited to a smart phone, a tablet computer, a wearable device (such as a smart watch, etc.), etc.

[0144] The embodiments in the specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts of each embodiment can be referred to each other.

[0145] The battery and the electric device provided by the application are described in detail above. The principles and implementation manners of the application are described by applying specific examples in this paper, and the above description of the examples is only used to help understand the scheme of the application and its core idea. It should be pointed out that, for ordinary skilled persons in the technical field, some improvements and modifications can be made to the application without departing from the principles of the application, and these improvements and modifications also fall within the protection scope of the application.

Claims

1. A battery, characterized by, The application relates to a battery cell and a film shell with a curved side wall, the battery cell comprising a diaphragm and first and second electrode plates alternately stacked in a first direction, the diaphragm being located between the first and second electrode plates. In a second direction, the battery cell has opposite first and second sides, and at least on the first side of the battery cell, a first end of a target first electrode plate protrudes from first ends of other first electrode plates and first ends of all second electrode plates; the target first electrode plate is one of the first electrode plates. In the first direction, the target first electrode plate has opposite first and second surfaces, and in a direction away from the first surface of the target first electrode plate, projections of the first ends of the other first electrode plates on the target first electrode plate are sequentially away from the first end of the target first electrode plate, and the second direction is perpendicular to the first direction. The first end of the first electrode plate is in contact with the side wall of the film shell. The projection of the second electrode plate in the second direction is located within the projection range of the adjacent first electrode plate in the second direction. On the second side of the battery cell, second ends of all the first electrode plates are flush, and second ends of all the second electrode plates are flush.

2. The battery of claim 1, wherein, Alternatively, On the second side of the battery cell, a second end of a target first electrode plate protrudes from second ends of other first electrode plates and second ends of all second electrode plates; in a direction away from the first surface of the target first electrode plate, projections of the second ends of the other first electrode plates on the target first electrode plate are sequentially away from the second end of the target first electrode plate. The other first electrode plates and the second electrode plates are only located on one side of the first surface of the target first electrode plate; or 3. The battery of claim 2, wherein the cathode is a lithium cobalt oxide cathode. In a direction away from the second surface of the target first electrode plate, projections of the first ends of the other first electrode plates on the target first electrode plate are sequentially away from the first end of the target first electrode plate. When the projections of the first ends of the other first electrode plates on the target first electrode plate are sequentially away from the first end of the target first electrode plate, at least on the first side of the battery cell, the side of the battery cell is a semicircular curved surface, and the diameter of the semicircular curved surface is equal to the thickness of the battery cell in the first direction.

4. The battery of claim 3, wherein the cathode is a lithium cobalt oxide cathode. At least on the first side of the battery cell, in a direction away from the first surface of the target first electrode plate, distances between the first ends of the other first electrode plates and / or the first ends of the second electrode plates and the first end of the target first electrode plate in the second direction form an arithmetic sequence; and / or 5. The battery of claim 1, wherein the cathode comprises a lithium metal oxide. On the second side of the battery cell, when second ends of all the first electrode plates are flush, and second ends of all the second electrode plates are flush, a distance between the second end of the second electrode plate and the second end of the first electrode plate in the second direction is d5, 0.5mm<=d5<=1mm; and / or On the first side of the battery cell and in a direction away from the first surface of the target first electrode plate, a first included angle between a line connecting the first end of the electrode plate farthest from the target first electrode plate and the first end of the target first electrode plate and the first surface of the target first electrode plate is alpha1, 35<=alpha1<=75; and / or On the second side of the battery cell, a second end of a target first electrode plate protrudes from second ends of other first electrode plates and second ends of all second electrode plates; in a direction away from the first surface of the target first electrode plate, projections of the second ends of the other first electrode plates on the target first electrode plate are sequentially away from the second end of the target first electrode plate. In the first side of the battery cell, and in the direction away from the second surface of the target first tab, the second angle between the line connecting the first end of the tab farthest from the target first tab and the second surface of the target first tab is a2, 35°≤a2≤75°; and / or, In the second side of the battery cell, and in the direction away from the first surface of the target first tab, the third angle between the line connecting the second end of the tab farthest from the target first tab and the second end of the target first tab and the first surface of the target first tab is a3, 35°≤a3≤75°; and / or, In the second side of the battery cell, and in the direction away from the second surface of the target first tab, the fourth angle between the line connecting the second end of the tab farthest from the target first tab and the second end of the target first tab and the second surface of the target first tab is a4, 35°≤a4≤75°.

6. The battery of claim 5, wherein the cathode is a lithium cobalt oxide cathode. The first angle and the second angle are equal in size; and / or, The third angle and the fourth angle are equal in size.

7. The battery of claim 1, wherein the cathode comprises a lithium metal oxide. In the first direction, when the tab farthest from the target first tab is a negative tab, the separator is distributed on the side of the negative tab away from the target first tab; and / or, The active material layer of the first tab comprises a silicon-based active material layer.

8. The battery of any one of claims 1 to 7, wherein, All the separators are equal in length in the second direction, and the length of the separator is greater than the length of the target first tab in the second direction; or, The length of the separator in the second direction is greater than the length of the adjacent first tab in the second direction, and the length of each separator in the second direction is not completely equal.

9. The battery of claim 8, wherein the cathode is a lithium cobalt oxide cathode. When all the separators are equal in length in the second direction, on the first side of the battery cell, the distance between the first end of the separator and the first end of the target first tab in the second direction is d6, 0.5mm≤d6≤1mm; and / or, When all the separators are equal in length in the second direction, on the second side of the battery cell, the distance between the second end of the separator and the second end of the target first tab in the second direction is d7, 0.5mm≤d7≤1mm; and / or, When the length of the separator in the second direction is greater than the length of the adjacent first tab in the second direction, and the length of each separator in the second direction is not completely equal, on the first side of the battery cell, the distance between the first end of the separator and the first end of the adjacent first tab in the second direction is d6, 0.5mm≤d6≤1mm; and / or, When the length of the separator in the second direction is greater than the length of the adjacent first tab in the second direction, and the length of each separator in the second direction is not completely equal, on the second side of the battery cell, the distance between the second end of the separator and the second end of the adjacent first tab in the second direction is d7, 0.5mm≤d7≤1mm.

10. An electric device, characterized by The battery comprises any one of the battery as claimed in claims 1 to 9. The battery comprises any one of the battery as claimed in claims 1 to 9.

Images