Battery, battery module and electric equipment

Abstract

The utility model provides a battery, a battery module and electric equipment, and relates to the field of batteries. The battery comprises a shell, an electrode assembly, electrolyte and electrolyte. Wherein a containing cavity is formed in the shell. The electrode assembly is located in the containing cavity, and a gap is formed between one side of the electrode assembly and the wall face of the containing cavity. The electrolyte is arranged in the containing cavity and makes contact with the electrode assembly. The electrolyte is in a solid state or a semi-solid state, and at least part of the electrolyte is arranged in the gap.

Description

Technical Field

[0001] This application relates to the technical field of batteries, and particularly to a battery, a battery module, and an electrical device. Background Art

[0002] With the increasingly fierce competition in the lithium-ion battery industry, cost reduction has become a key factor in the competition of the lithium-ion battery industry. To reduce the manufacturing and system management costs of batteries, related technologies increase the battery capacity by increasing the electrode size, which can not only reduce the material cost, but also reduce the production cost and system management cost.

[0003] Increasing the battery size in the three dimensions of length, width, and height can all increase the single battery capacity. Increasing the size in the height direction can improve the battery volume utilization rate to a greater extent, thereby enhancing the volume energy density. However, as the battery height increases, the electrode height also increases, the distribution of the electrolyte in the height direction becomes more uneven, and the resistance of the electrolyte to transfer from the bottom to the top becomes greater. In the later stage of battery use, due to the lack of sufficient electrolyte in the height direction of the battery, the lithium-ion transfer resistance increases, and the battery polarization increases, which will greatly affect the battery electrical performance. Summary of the Utility Model

[0004] Embodiments of this application provide a battery, a battery module, and an electrical device, which can improve the problem of insufficient electrolyte at the top of the electrode assembly caused by the increase in battery height, so that the battery has good electrical performance.

[0005] In a first aspect, this application provides a battery, which includes a housing, an electrode assembly, an electrolyte, and an electrolyte. Among them, an accommodation cavity is provided inside the housing. The electrode assembly is located in the accommodation cavity, and there is a gap between one side of the electrode assembly and the wall surface of the accommodation cavity. The electrolyte is arranged in the accommodation cavity and is in contact with the electrode assembly. The electrolyte is solid or semi-solid, and at least part of the electrolyte is arranged in the gap.

[0006] In a possible design of the first aspect, the height of the electrode assembly is greater than half of the theoretical wetting height of the electrolyte.

[0007] In a possible design of the first aspect, the accommodation cavity is provided with a limiting block, and the electrode assembly abuts against the limiting block.

[0008] In a possible design of the first aspect, the accommodation cavity is provided with at least two limiting blocks, and the electrolyte is arranged between the two limiting blocks.

[0009] In a possible design of the first aspect, the electrode assembly includes a first tab group and a second tab group. The first tab group and the second tab group are arranged on the same side of the electrode assembly, the first tab group and the second tab group are arranged between the two limiting blocks, and the electrolyte is arranged between the first tab group and the second tab group.

[0010] In a possible design of the first aspect, the electrolyte is in the shape of a cuboid, a cylinder, an elliptical cylinder or a prism.

[0011] In a possible design of the first aspect, the electrolyte is in the shape of a cuboid. The length of the electrolyte is less than or equal to the distance between the two limiting blocks, and the width of the electrolyte is less than or equal to the width of the electrode assembly.

[0012] In a possible design of the first aspect, the concentration C and volume V of the electrolyte satisfy the following relationship:

[0013] C * V = A * (L1 - H1) / L1 * α,

[0014] where C is the concentration of the electrolyte, V is the volume of the electrolyte, A is the designed capacity of the battery, L1 is the height of the electrode assembly, H1 is the theoretical wetting height of the electrolyte, and α is the electrolyte coefficient of the electrolyte.

[0015] In a second aspect, the present application provides a battery module, including the battery according to the first aspect and any of its possible design manners.

[0016] In a third aspect, the present application provides an electrical device, including the battery module according to the second aspect.

[0017] Advantageous effects of the embodiments of the present application:

[0018] The present application is provided with an electrolyte solution and an electrolyte. During the use of the battery, the side of the battery close to the electrolyte is set upward. At this time, the electrolyte is located at the top of the electrode assembly. The electrode assembly is in contact with the electrolyte solution, and the electrolyte solution wets upward to the theoretical wetting height, and the electrolyte will slowly dissolve and slowly diffuse from top to bottom, which can solve the problem of insufficient electrolyte solution at the top of the electrode assembly caused by the increase in the height of the battery, avoid the increase in the polarization of the electrode assembly, and enable the battery to have good electrical performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application. For those skilled in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0020] Figure 1 It is a schematic structural diagram of a battery provided by an embodiment of the present application;

[0021] Figure 2 It is a comparison diagram of the cycling performance of the first battery and the second battery provided by an embodiment of the present application;

[0022] Figure 3 This is a comparison chart of the cycling performance of the third battery and the fourth battery provided by the embodiments of the present application.

[0023] In the figure:

[0024] 110 - housing; 120 - electrode assembly; 130 - electrolyte; 140 - electrolyte; 150 - limiting block;

[0025] 111 - accommodation cavity; 112 - first pole; 113 - second pole;

[0026] 121 - first tab group; 122 - second tab group. Detailed implementation manners

[0027] Next, the technical solutions in the present application will be described with reference to the accompanying drawings.

[0028] In the embodiments of the present application, words such as "exemplary" or "for example" are used to represent examples, illustrations or explanations. Any embodiment or design solution described as "exemplary" or "for example" in the embodiments of the present application should not be construed as being more preferred or having more advantages than other embodiments or design solutions. Rather, the use of words such as "exemplary" or "for example" is intended to present related concepts in a specific manner.

[0029] In the embodiments of the present application, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of such features.

[0030] It should be understood that the terms used in the description of various examples herein are only for the purpose of describing specific examples and are not intended to be limiting. As used in the description of various examples, the singular forms "a", "an" and "the" are also intended to include the plural forms unless the context clearly indicates otherwise.

[0031] In the present application, "at least one" means one, two or more, and "a plurality" means more than two. "At least one of the following" or its similar expressions refer to any combination of these items, including any combination of single items or plural items. For example, at least one of a, b, or c can represent: a, b, c, a - b, a - c, b - c, or a - b - c, where a, b, c can be single or multiple.

[0032] It should also be understood that in this application, unless otherwise clearly specified and limited, the term "connection" should be understood in a broad sense. For example, "connection" can be a fixed connection, a sliding connection, a detachable connection, or integrated, etc.; it can be directly connected or indirectly connected through an intermediate medium.

[0033] It should also be understood that the term "comprising" (also known as "includes", "including", "comprises" and / or "comprising") when used in this specification specifies the presence of the stated features, integers, steps, operations, elements, and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or their groups.

[0034] It should be understood that the "one embodiment", "another embodiment", and "a possible design method" mentioned throughout the specification mean that specific features, structures, or characteristics related to the embodiment or implementation method are included in at least one embodiment of this application. Therefore, the "in one embodiment of this application" or "in another embodiment of this application", "a possible design method" that appear throughout the specification do not necessarily refer to the same embodiment. In addition, these specific features, structures, or characteristics can be combined in one or more embodiments in any suitable manner.

[0035] It should also be understood that the specific numerical values mentioned in the embodiments of this application do not limit the specific sizes of specific features and structures. The relevant numerical values may be for illustrative convenience or the best theoretical values of a certain feature in theory. In practice, the relevant sizes can be a range around this value. For example, this range can be ±10% of the best theoretical value, or ±20% of the best theoretical value, and in practice, it is subject to achieving the corresponding technical effects.

[0036] As the competition in the lithium-ion battery industry becomes increasingly fierce, cost reduction has become a key factor in the competition in the lithium-ion battery industry. In order to reduce the manufacturing and system management costs of the battery, related technologies increase the battery capacity by increasing the electrode size, which can not only reduce the material cost, but also reduce the production cost and system management cost.

[0037] Increasing the battery size in the three dimensions of length, width, and height can all improve the single-cell capacity. Increasing the size in the height direction can improve the battery volume utilization rate to a greater extent, thereby increasing the volumetric energy density. However, as the battery height increases, the electrode height also increases, and the distribution of the electrolyte in the height direction becomes more uneven. The resistance of the electrolyte to transfer from the bottom to the top becomes greater. In the later stage of battery use, due to the lack of sufficient electrolyte in the battery height direction, the lithium-ion transfer resistance increases, and the battery polarization increases, which will greatly affect the electrical performance of the battery.

[0038] Before introducing the specific solutions of the embodiments of the present application, the theoretical basis adopted by the solutions provided by the embodiments of the present application will be introduced first.

[0039] Referring to Formula (1), Formula (1) is the Lucas-Washburn equation.

[0040]

[0041] Among them, h is the infiltration height of the electrolyte at time t;

[0042] k is the infiltration coefficient of the electrolyte in the electrode or diaphragm. The larger the value of k, the faster the electrolyte flows in the porous material;

[0043] r is the effective radius of the electrode pores or diaphragm pores;

[0044] γ is the surface tension of the electrolyte;

[0045] θ is the contact angle between the electrolyte and the electrode or diaphragm;

[0046] η is the viscosity of the electrolyte.

[0047] Within the preset time, there is a theoretical infiltration height for the infiltration height of the electrolyte. In the same chemical system design, assuming the height of the electrode assembly in the battery is H, within the preset time t, the theoretical infiltration height of the electrolyte is h.

[0048] Then, when H ≤ 0.5h, the infiltration height of the electrolyte in the height direction can meet the requirements of the battery. When H > 0.5h, the infiltration height of the electrolyte in the height direction cannot meet the requirements of the battery. In the later stage of battery use, due to the lack of sufficient electrolyte in the height direction of the battery, the lithium-ion transmission resistance increases, and the battery polarization increases, which will greatly affect the electrical performance of the battery.

[0049] To solve the above problems, the embodiments of the present application provide a battery that can still provide sufficient electrolyte for the electrodes and ensure the electrical performance of the battery after the size of the battery, especially the size in the height direction, is increased.

[0050] Refer to Figure 1 , Figure 1 is a schematic structural diagram of a battery provided by an embodiment of the present application. As Figure 1 shown, a battery provided by an embodiment of the present application includes a housing 110, an electrode assembly 120, an electrolyte 130, and an electrolyte 140. Among them, an accommodation cavity 111 is provided inside the housing 110, and both the electrode assembly 120 and the electrolyte 130 are provided in the accommodation cavity 111. Among them, when the electrode assembly 120 is provided in the accommodation cavity 111, there is a gap between one side of the electrode assembly 120 and the wall surface of the accommodation cavity 111.

[0051] Among them, a filling port is provided on the housing 110, and the electrolyte 130 is filled into the accommodation cavity 111 through the filling port of the housing 110 and contacts the electrode assembly 120, so that the electrode assembly 120 is immersed in the electrolyte 130. The electrolyte 140 is solid or semi-solid, and the electrolyte 140 is disposed on one side of the electrode assembly 120, and at least a part of the electrolyte 140 is located in the gap between the electrode assembly 120 and the accommodation cavity 111.

[0052] Exemplarily, when the battery is placed upright, the electrode assembly 120 is disposed in the accommodation cavity 111, the bottom of the electrode assembly 120 contacts the bottom of the accommodation cavity 111, and there is a gap between the top of the electrode assembly 120 and the top of the accommodation cavity 111. The electrolyte 140 is disposed on the top of the electrode assembly 120, and at least a part of the electrolyte 140 is located in the gap between the top of the electrode assembly 120 and the top of the accommodation cavity 111.

[0053] In the embodiment of the present application, by providing the electrolyte 130 and the electrolyte 140, the electrolyte 130 is liquid, the electrode assembly 120 is immersed in the electrolyte 130, and the electrolyte 130 can be infiltrated to the theoretical infiltration height. The electrolyte 140 is disposed at the top end of the electrode assembly 120. During the use of the battery, the electrolyte 140 will slowly dissolve and slowly diffuse from top to bottom, which can solve the problem of insufficient electrolyte 130 at the top of the electrode assembly 120 caused by the increase in the height of the battery, so that the battery has good electrical performance.

[0054] In addition, during the use of the battery, the heat generated by the battery will accelerate the dissolution of the electrolyte 140, which can effectively solve the infiltration problem of the electrode assembly 120.

[0055] In an embodiment of the present application, the height of the electrode assembly 120 is greater than half of the theoretical infiltration height of the electrolyte 130. In this case, the infiltration height of the electrolyte 130 in the height direction cannot meet the requirements of the battery, and the slowly dissolved electrolyte 140 slowly diffuses from top to bottom, which can solve the problem of insufficient electrolyte 130 at the top of the electrode assembly 120 caused by the increase in the height of the battery.

[0056] It should be noted that in the embodiment of the present application, the theoretical infiltration height of the electrolyte 130 refers to the theoretical infiltration height of the electrolyte 130 within a preset time. Those skilled in the art can set the specific value of the preset time according to actual needs. For example, in practical applications, the preset time can be set to 24 hours, and the environmental temperature at which the electrolyte 130 infiltrates can be set to 45 °C.

[0057] In an embodiment of the present application, the electrode assembly 120 may include a positive electrode plate, a negative electrode plate, and a separator. A plurality of positive electrode plates and a plurality of negative electrode plates are alternately stacked together, and among them, adjacent positive electrode plates and negative electrode plates are separated by a separator.

[0058] In an embodiment of the present application, to facilitate the assembly of the electrode assembly 120 into the accommodation cavity 111, the size of the electrode assembly 120 is generally smaller than that of the accommodation cavity 111. In particular, the height dimension of the electrode assembly 120 is smaller than the height dimension of the accommodation cavity 111. To prevent the electrode assembly 120 from shaking in the accommodation cavity 111, a limiting block 150 is provided at the top of the accommodation cavity 111. When the electrode assembly 120 is assembled into the accommodation cavity 111, the top end of the electrode assembly 120 abuts against the limiting block 150.

[0059] It should be noted that in the embodiment of the present application, the top end of the electrode assembly 120 abutting against the limiting block 150 means that the top end of the electrode assembly 120 may form contact with the limiting block 150, or it may mean that there is a certain gap between the top end of the electrode assembly 120 and the limiting block 150, but this gap is small and does not affect the stability of the electrode assembly 120 in the accommodation cavity 111.

[0060] In an embodiment of the present application, as Figure 1 shown, two limiting blocks 150 are provided at the top of the accommodation cavity 111. Among them, the two limiting blocks 150 are respectively arranged at the corners formed by the top of the accommodation cavity 111 and the two side walls. Since there is a gap between the top end of the electrode assembly 120 and the top of the accommodation cavity 111, by providing two limiting blocks 150, the two limiting blocks 150 respectively limit the two sides of the top end of the electrode assembly 120, which can make the electrode assembly 120 more stable in the accommodation cavity 111. Since the electrolyte 140 is arranged at the top end of the electrode assembly 120, the electrolyte 140 can be arranged in the space between the two limiting blocks 150.

[0061] In an embodiment of the present application, as Figure 1 shown, the electrode assembly 120 further includes a first tab group 121 and a second tab group 122. The first tab group 121 and the second tab group 122 are arranged on the same side of the electrode assembly 120, and the first tab group 121 and the second tab group 122 are arranged between the two limiting blocks 150. The first tab group 121 is connected to the first pole column 112 on the battery, and the second tab group 122 is connected to the second pole column 113 on the battery. The electrolyte 140 is arranged between the first tab group 121 and the second tab group 122.

[0062] Arranging the electrolyte 140 between the first tab group 121 and the second tab group 122 can avoid the influence of the first tab group 121 and the second tab group 122, and the arrangement is more convenient.

[0063] In an embodiment of the present application, the shape of the electrolyte 140 can be set to a cuboid shape, a cylindrical shape, an elliptical cylindrical shape, a polygonal prism shape, or other irregular shapes. Specifically, the shape of the electrolyte 140 can be set according to the shape of the electrode assembly 120. For example, if the electrode assembly 120 is cuboid-shaped, the electrolyte 140 can be set to a cuboid shape. If the electrode assembly 120 is cylindrical-shaped, the electrolyte 140 can be set to a cylindrical shape. If the electrode assembly 120 is cube-shaped, the electrolyte 140 can be set to a cube shape.

[0064] In an embodiment of the present application, the battery is a square shell battery, that is, the overall shape of the housing 110 is cuboid-shaped, and the shape of the battery cell inside the battery is also cuboid-shaped. In order to enable the electrolyte 140 to better infiltrate the electrode assembly 120, the shape of the electrolyte 140 is also set to a cuboid shape. The larger the area of the electrolyte 140 covering the top of the electrode assembly 120, the better the infiltration effect of the electrolyte 140 on the electrode assembly 120 after dissolution.

[0065] As Figure 1 shown, since the limiting blocks 150 are provided on both sides of the top of the accommodation cavity 111, and the electrolyte 140 is arranged between the two limiting blocks 150, the maximum length of the electrolyte 140 is the distance between the two limiting blocks 150. By arranging the two limiting blocks 150 close to the two side walls of the accommodation cavity 111 respectively, the distance between the two limiting blocks 150 is the largest.

[0066] In the embodiment of the present application, the sizes of the two limiting blocks 150 are the same. Among them, let the length of the accommodation cavity 111 be L, and the width dimension of the limiting block 150 in the length direction of the accommodation cavity 111 be m. Then the maximum distance between the two limiting blocks 150 is L - 2m. Therefore, the length of the electrolyte 140 can be set to be less than or equal to L - 2m. Generally, there is no corresponding limiting structure in the width direction of the electrode assembly 120. The shaking of the electrode assembly 120 in the width direction of the accommodation cavity 111 is mainly restricted by setting the ratio between the width dimension of the electrode assembly 120 and the width dimension of the accommodation cavity 111. When setting the size of the electrolyte 140, the width of the electrolyte 140 can be set to be equal to the width of the electrode assembly 120, or the width of the electrolyte 140 can be set to be less than the width of the electrode assembly 120.

[0067] When the length of the electrolyte 140 is set to be equal to L - 2m and the width of the electrolyte 140 is set to be equal to the width of the electrode assembly 120, the covering area of the electrolyte 140 on the electrode assembly 120 is the largest at this time. When the electrolyte 140 dissolves, it can better infiltrate the electrode assembly 120.

[0068] It should be noted that at this time, due to the influence of the first tab group 121 and the second tab group 122, corresponding notches can be provided on the electrolyte 140, so that the first tab group 121 and the second tab group 122 pass through the notches provided on the electrolyte 140.

[0069] In an embodiment of the present application, in order to achieve better wetting of the electrode assembly 120 by the electrolyte 140, the concentration and volume of the electrolyte 140 satisfy the following relational expression (2):

[0070] C*V =A*(H1-H2) / L1*α (2)

[0071] Wherein, C is the concentration of the electrolyte 140, V is the volume of the electrolyte 140. A is the designed capacity of the battery, H1 is the height of the electrode assembly 120, H2 is the theoretical wetting height of the electrolyte 130, and α is the electrolyte coefficient of the electrolyte 130.

[0072] The electrolyte coefficient of the electrolyte 130 is generally set as: 0.9≤α≤5. Among them, when the electrolyte coefficient α of the electrolyte 130 is 1.1 to 3.3, the effect is better.

[0073] When the volume of the electrolyte 140 is determined, the thickness of the electrolyte 140 can be obtained in combination with the length and width of the electrolyte 140. When the height of the battery is set relatively high, the concentration and thickness of the electrolyte 140 can be adjusted according to the actual height requirements, so as to meet the requirements of the electrodes for the electrolyte 130 in batteries of different heights.

[0074] In an embodiment of the present application, the electrolyte 130 generally can adopt a liquid lithium-ion electrolyte 130, or adopt a liquid electrolyte 130 in conventional technologies. The specific components of the electrolyte 130 are not limited in the embodiments of the present application. The electrodes in the battery generally can adopt graphite electrodes. The electrolyte 130 is used to conduct ions and can form a solid electrolyte interface (SEI) film on the surface of the graphite electrode.

[0075] In an embodiment of the present application, a film-forming additive for improving the cycle rate performance of the battery is added to the electrolyte 140 relative to the electrolyte 130. Among them, the film-forming additives mainly include unsaturated lipid additives, sulfur-containing additives, lithium salt additives, inorganic compound additives and other additives.

[0076] Among them, the unsaturated lipid additives are mainly used to improve the cycle rate performance of the battery. The unsaturated lipid additives mainly include VC, FEC, VEC, CC, AEC, VA, etc.

[0077] Sulfur-containing additives mainly include additives such as sultones and sulfates. Lithium salt additives are mainly new lithium salts, including LiBOB, LiODFB, etc. And it includes any one or a mixture of several of lithium hexanitrophosphate, lithium bis(fluorosulfonyl)imide, lithium bis(trifluoromethanesulfonyl)imide, lithium lanthanum zirconium oxide, and lithium titanium aluminum phosphate.

[0078] Other additives can include silane additives, ionic liquids, nitrogen-containing additives, etc.

[0079] In the embodiments of the present application, the electrolyte 140 belongs to a gel polymer, including physically cross-linked type and chemically cross-linked type. The physically cross-linked electrolyte 130 includes polyacrylonitrile (PAN) and its copolymers, polyvinylidene fluoride (PVDF) and its copolymers, PMMA and its copolymers, etc.

[0080] The chemically cross-linked electrolyte 130 includes acrylate polymers with a content of 0.1 - 3 wt%. The organic solvents include chain carbonates, cyclic carbonates, fatty acid carboxylates, etc., with a content of 5 - 95 wt%. The electrolyte 140 salt is a lithium salt, including LiPF6, LiBF4, LiAsF6, LiSbF6, etc., with a content of 0.5 - 5 mol / L%. The additive is a polymer initiator, including azo initiators and peroxide initiators, with a content of 0.001 - 1 wt%.

[0081] In an embodiment of the present application, by setting different electrolytes 130 and electrolytes 140, after the electrolyte 140 is dissolved, the performance of the battery can be improved.

[0082] Next, the performance of the battery in the embodiments of the present application is tested.

[0083] Example 1

[0084] The embodiments of the present application provide two batteries for comparative testing, including a first battery and a second battery. Among them, only an electrolyte is provided in the first battery, and the second battery is the battery provided by the embodiments of the present application. That is, the second battery includes an electrolyte 130 (liquid), and an electrolyte 140 (solid / semi-solid) is provided at the top of the electrode assembly 120. The other parameters of the first battery and the second battery are the same. For example, the battery cell of the first battery is composed of a positive electrode plate, a negative electrode plate, and a separator, and the battery cell of the second battery is composed of a positive electrode plate, a negative electrode plate, and a separator, and the battery cell parameters of both are the same.

[0085] The heights of both the first battery and the second battery are set to 320 mm, and the chemical systems of the first battery and the second battery are the same. The theoretical wetting height of the electrolyte in this chemical system is 242.3 mm. From the above data, it can be seen that 320 mm > 242.3 / 2 = 121.15 mm, that is, the heights of the first battery and the second battery far exceed half of the theoretical wetting height of the electrolyte.

[0086] The first battery is tested in cycles according to the standard 1C fast charging process, and the second battery is also tested in cycles according to the standard 1C fast charging process.

[0087] The cycling performance of the first battery and the second battery can be referred to Figure 2 , Figure 2 which is the comparison chart of the cycling performance of the first battery and the second battery provided in the embodiments of the present application.

[0088] As Figure 2 shown, for the first battery with only the electrolyte set, compared with the second battery with both the electrolyte 130 and the electrolyte 140 set, after 860 cycles, the cycling capacity retention rate of the first battery is significantly lower than that of the second battery. This result shows that by setting both the electrolyte 130 and the electrolyte 140 in the second battery and setting the electrolyte 140 at the top of the electrode assembly 120, a good improvement effect on the cycling performance of the battery is achieved.

[0089] Example 2

[0090] The embodiments of the present application provide two batteries for comparative testing, including a third battery and a fourth battery. Among them, only the electrolyte is set in the third battery, and the fourth battery is the battery provided in the embodiments of the present application. That is, the fourth battery includes the electrolyte 130 (liquid), and the electrolyte 140 (solid / semi-solid) is set at the top of the electrode assembly 120. The other parameters of the third battery and the fourth battery are the same. For example, the battery core of the third battery is composed of a positive electrode plate, a negative electrode plate and a separator, and the battery core of the fourth battery is composed of a positive electrode plate, a negative electrode plate and a separator, and the battery core parameters of the two are the same.

[0091] The heights of both the third battery and the fourth battery are set to 230 mm, and the chemical systems of the third battery and the fourth battery are the same. The theoretical wetting height of the electrolyte in this chemical system is 242.3 mm. From the above data, it can be seen that 230 mm > 242.3 / 2 = 121.15 mm, that is, the heights of the third battery and the fourth battery exceed half of the theoretical wetting height of the electrolyte, but compared with Example 1, the heights of the third battery and the fourth battery are both reduced.

[0092] The third battery is tested in cycles according to the standard 1C fast charging process, and the fourth battery is also tested in cycles according to the standard 1C fast charging process.

[0093] The cycling performance of the third battery and the fourth battery can be referred to Figure 3 , Figure 3 which is the comparison chart of the cycling performance of the third battery and the fourth battery provided by the embodiments of the present application.

[0094] As Figure 3 shown, for the third battery with only electrolyte, after 230 cycles, the cycling capacity retention rate is 92.7%. For the fourth battery with both electrolyte 130 and electrolyte 140, after 500 cycles, the cycling capacity retention rate is 95%. When the second battery has more cycling weeks, its cycling capacity retention rate is still higher than that of the first battery. This result shows that by setting both electrolyte 130 and electrolyte 140 in the fourth battery and setting electrolyte 140 at the top of the electrode assembly 120, a good improvement effect on the cycling performance of the battery is achieved.

[0095] The above is only the specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed in the present application, and all should be covered by the protection scope of the present application.

[0096] Each embodiment in this specification is described in a progressive manner. The key point of each embodiment is to illustrate the differences from other embodiments. The same or similar parts among the embodiments can be referred to each other.

[0097] Although the preferred embodiments of the embodiments of the present application have been described, those skilled in the art can make additional changes and modifications once they know the basic creative concepts. Therefore, the protection scope of the present application includes the preferred embodiments and all changes and modifications falling within the scope of the embodiments of the present application.

[0098] In this article, specific examples are used to elaborate on the working principles and implementation manners of the batteries, battery modules, and electrical equipment of the present application. The descriptions of the above embodiments are only used to help understand the specific settings and core ideas of the present application; at the same time, for those of ordinary skill in the art, according to the idea of the present application, there will be changes in the specific implementation manners and application scopes. In summary, the content of this specification should not be construed as a limitation to the present application.

[0099] The above content is only the specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any change or substitution within the technical scope disclosed in the present application should be covered by the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A battery, characterized in that, Comprising: A housing having an accommodation cavity therein; An electrode assembly located within the accommodation cavity, with a gap between one side of the electrode assembly and the wall surface of the accommodation cavity; An electrolyte disposed within the accommodation cavity and in contact with the electrode assembly; An electrolyte, being solid or semi-solid, with at least a portion of the electrolyte disposed within the gap.

2. The battery according to claim 1, characterized in that, The height of the electrode assembly is greater than half of the theoretical wetting height of the electrolyte.

3. The battery according to claim 2, wherein, The accommodation cavity is provided with a limiting block, and the electrode assembly abuts against the limiting block.

4. The battery according to claim 3, characterized in that, The accommodation cavity is provided with at least two of the limiting blocks, and the electrolyte is disposed between the two limiting blocks.

5. The battery according to claim 4, characterized in that, The electrode assembly includes a first tab group and a second tab group, the first tab group and the second tab group are disposed on the same side of the electrode assembly, the first tab group and the second tab group are disposed between the two limiting blocks, and the electrolyte is disposed between the first tab group and the second tab group.

6. The battery according to any one of claims 1 to 5, characterized in that, The shape of the electrolyte is rectangular parallelepiped, cylindrical, elliptical cylindrical or polygonal prismatic.

7. The battery according to claim 6, characterized in that, The shape of the electrolyte is rectangular parallelepiped, the length of the electrolyte is less than or equal to the distance between the two limiting blocks, and the width of the electrolyte is less than or equal to the width of the electrode assembly.

8. The battery according to any one of claims 2 to 5, characterized in that, The concentration C and volume V of the electrolyte satisfy the following relationship: C * V = A * (L1 - H1) / L1 * α, where C is the concentration of the electrolyte, V is the volume of the electrolyte, A is the designed capacity of the battery, L1 is the height of the electrode assembly, H1 is the theoretical wetting height of the electrolyte, and α is the electrolyte coefficient of the electrolyte.

9. A battery module, characterized in that, Comprising a battery according to any one of claims 1 to 8.

10. An electrical device, characterized in that, Comprising a battery module according to claim 9.

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