Battery monomer, battery and electric equipment

Abstract

The utility model provides a single battery, a battery and electric equipment, the single battery comprises a shell, an electrode assembly, an electrolyte and a blocking piece, the shell is provided with a containing cavity, the electrode assembly is contained in the containing cavity, the electrode assembly comprises a first pole piece and a second pole piece which are opposite in polarity, and the first pole piece and the second pole piece are stacked and spaced to form a gap; the gap penetrates through the outer side of the electrode assembly to form a seam, the electrolyte is contained in the gap, and the blocking piece covers the seam to prevent the electrolyte from being separated from the gap through the seam. According to the battery monomer provided by the invention, the blocking piece covers the seam of the electrode assembly, so that in the charging process of the battery monomer, even if the electrode assembly expands, under the blocking effect of the blocking piece, the electrolyte can be effectively prevented from being separated from the seam through the seam, and the condition that some parts of the electrode assembly are lack of electrolyte is effectively improved; therefore, the risk of metal dendritic crystal precipitation of the electrode assembly is effectively reduced, and the performance of the battery monomer is effectively improved.

Description

Technical Field

[0001] The present application belongs to the field of battery technology, and more specifically, relates to a battery cell, a battery and an electrical device. Background Art

[0002] As the smallest unit of a battery, a battery cell usually includes a shell and an electrode assembly contained in the shell. The electrode assembly undergoes an electrochemical reaction with the electrolyte to form an electric current. However, during the charging process of the battery cell, the electrode assembly will expand, and the expanded electrode assembly will squeeze out the electrolyte inside the electrode assembly, causing a lack of electrolyte in certain parts of the electrode assembly, thereby causing metal dendrites to precipitate in the electrode assembly, which is not conducive to improving the performance of the battery cell. Utility Model Content

[0003] The purpose of the embodiments of the present application is to provide a battery cell, a battery and an electrical device to solve the technical problem in the related art that metal dendrites are easily precipitated from the battery cell, resulting in a decrease in the performance of the battery cell.

[0004] In order to achieve the above-mentioned purpose, the technical solution adopted in the embodiment of the present application is: to provide a battery cell, comprising:

[0005] A housing having a cavity;

[0006] An electrode assembly is accommodated in the cavity, the electrode assembly comprises a first electrode piece and a second electrode piece with opposite polarities, the first electrode piece and the second electrode piece are stacked and spaced to form a gap, and the gap penetrates the outer side of the electrode assembly to form a seam;

[0007] The electrolyte is contained in the gap;

[0008] The blocking member is arranged on the slit opening to prevent the electrolyte from escaping from the slit opening.

[0009] The battery cell provided in the embodiment of the present application has at least the following beneficial effects: the blocking member in the battery cell provided in the embodiment of the present application is covered on the slit of the electrode assembly, so that during the charging process of the battery cell, even if the electrode assembly expands, the blocking action of the blocking member can effectively prevent the electrolyte from escaping from the gap through the slit, effectively improving the situation of lack of electrolyte in certain parts of the electrode assembly, thereby effectively reducing the risk of metal dendrites precipitating from the electrode assembly, and effectively improving the performance of the battery cell.

[0010] In some embodiments of the present application, the shell includes a first wall for supporting the electrode assembly, the blocking member includes a first blocking portion, a gap passes through a side of the electrode assembly away from the first wall to form a first slit, and the first blocking portion covers at least a portion of the first slit.

[0011] By adopting the above technical solution, the situation of lack of electrolyte on the top side of the electrode assembly is effectively improved, thereby effectively reducing the risk of metal dendrite precipitation in the electrode assembly and effectively improving the performance of the battery cell.

[0012] In some embodiments of the present application, the blocking member also includes two second blocking portions, which are arranged on opposite sides of the first blocking portion along the width direction of the battery cell, and the gap penetrates the opposite sides of the electrode assembly along the width direction of the battery cell to form a second slit, and the second blocking portion covers at least part of the second slit.

[0013] By adopting the above technical solution, the situation of lack of electrolyte on the top side of the electrode assembly is further improved, thereby further reducing the risk of metal dendrite precipitation in the electrode assembly and further improving the performance of the battery cell.

[0014] In some embodiments of the present application, the first electrode sheet is a negative electrode sheet, and the blocking member includes a liquid absorption portion, which is attached to the surface of the first electrode sheet along the thickness direction.

[0015] By adopting the above technical solution, the liquid absorption part can absorb the electrolyte located outside the electrode assembly and replenish the electrolyte to the surface of the first electrode sheet, thereby alleviating the precipitation of metal dendrites in the electrode assembly and improving the performance of the battery cell.

[0016] In some embodiments of the present application, the blocking member is provided with exhaust holes.

[0017] By adopting the above technical solution, not only can the electrolyte be prevented from escaping from the gap through the seam, but the gas generated by the electrode assembly during the charging and discharging process can be discharged to the outside of the electrode assembly through the exhaust pores, so as to alleviate the expansion of the electrode assembly, further improve the lack of electrolyte in certain parts of the electrode assembly, thereby further reducing the risk of metal dendrite precipitation in the electrode assembly and further improving the performance of the battery cell.

[0018] In some embodiments of the present application, the porosity of the barrier is 25%-50%.

[0019] By adopting the above technical solution, not only can the blocking member effectively prevent the electrolyte from escaping from the gap through the slit, but the gas generated by the electrode assembly during the charging and discharging process can also be discharged to the outside of the electrode assembly through the exhaust pores, thereby effectively alleviating the expansion of the electrode assembly.

[0020] In some embodiments of the present application, there are multiple blocking members, and the multiple blocking members are stacked.

[0021] By adopting the above technical solution, under the premise that the gas generated by the electrode assembly can be discharged to the outside of the electrode assembly through the exhaust pores, it can more effectively prevent the electrolyte from escaping through the gaps, further improving the situation of lack of electrolyte in certain parts of the electrode assembly, thereby further reducing the risk of metal dendrite precipitation in the electrode assembly and further improving the performance of the battery cell.

[0022] In some embodiments of the present application, the porosity of the plurality of barriers gradually decreases in a direction away from the electrode assembly.

[0023] By adopting the above technical solution, not only can the electrolyte be effectively prevented from escaping from the gap through the slit, but also the blocking member is conducive to the reabsorption of the electrolyte. The electrolyte reabsorbed by the blocking member can be replenished into the gap of the electrode assembly, further improving the situation of lack of electrolyte in certain parts of the electrode assembly, thereby further reducing the risk of metal dendrite precipitation in the electrode assembly and further improving the performance of the battery cell.

[0024] In some embodiments of the present application, the blocking member is a film member, and the blocking member is attached to the outer side of the electrode assembly.

[0025] By adopting the above technical solution, the space occupied by the blocking member is effectively reduced, thereby effectively improving the volume energy density of the battery cell.

[0026] In some embodiments of the present application, the battery cell further includes a connecting member, and the blocking member is fixedly connected to the electrode assembly via the connecting member.

[0027] By adopting the above technical solution, the blocking member can be effectively fixed on the electrode assembly.

[0028] In some embodiments of the present application, the connecting member is an adhesive member.

[0029] By adopting the above technical solution, it is convenient to fix the blocking member on the electrode assembly, thereby effectively improving the production efficiency of the battery cell.

[0030] In some embodiments of the present application, the blocking member includes a connecting portion, which is fixedly connected to the electrode assembly.

[0031] By adopting the above technical solution, the blocking member can be effectively fixed on the electrode assembly.

[0032] In some embodiments of the present application, the connecting portion is an adhesive portion.

[0033] By adopting the above technical solution, it is convenient to fix the blocking member on the electrode assembly, thereby effectively improving the production efficiency of the battery cell.

[0034] To achieve the above objectives, an embodiment of the present application further provides a battery, comprising the battery cell described in any of the above embodiments.

[0035] The battery provided by the embodiments of the present application has at least the following beneficial effects: the battery provided by the embodiments of the present application adopts the battery cell described in any of the above embodiments, thereby effectively improving the performance of the battery.

[0036] To achieve the above objectives, an embodiment of the present application further provides an electrical device, including the above battery.

[0037] The electric device provided in the embodiment of the present application has at least the following beneficial effects: the electric device provided in the embodiment of the present application adopts the above-mentioned battery, thereby effectively improving the performance of the electric device. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0039] Figure 1 A schematic diagram of the structure of a vehicle provided in an embodiment of the present application;

[0040] Figure 2 A schematic diagram of the explosion structure of a battery provided in an embodiment of the present application;

[0041] Figure 3 A schematic diagram of the structure of a battery cell provided in an embodiment of the present application;

[0042] Figure 4 for Figure 3 The exploded structure diagram of the battery cell shown;

[0043] Figure 5 for Figure 4 A schematic diagram of the structure of the electrode assembly in the battery cell shown;

[0044] Figure 6 A schematic diagram of the connection structure between the electrode assembly and the blocking member provided in one embodiment of the present application;

[0045] Figure 7 A schematic diagram of the connection structure between the electrode assembly and the blocking member provided in another embodiment of the present application.

[0046] Among them, the reference numerals in the figure are:

[0047] 1000. Vehicles;

[0048] 100. Battery;

[0049] 10. Box body; 11. First part; 12. Second part;

[0050] 20. Battery cell; 21. Shell; 211. Shell; 2111. First wall; 212. End cover; 213. Receptacle; 22. Electrode assembly; 221. First pole piece; 222. Second pole piece; 223. Slit; 2231. First slit; 2232. Second slit; 224. Tab; 23. Blocking member; 231. First blocking portion; 232. Second blocking portion; 233. Liquid absorption portion; 234. Exhaust pore; 235. Connecting portion; 24. Connecting member; 25. Electrode terminal;

[0051] 200, controller;

[0052] 300. Motor. DETAILED DESCRIPTION

[0053] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0054] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0055] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0056] In addition, the terms "first", "second", "third", and "fourth" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first", "second", "third", and "fourth" may explicitly or implicitly include one or more of the feature. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0057] As the smallest unit of a battery, a battery cell generally includes a housing, an electrode assembly and an electrolyte, wherein the electrode assembly and the electrolyte are contained in the housing. The electrode assembly includes a positive electrode sheet and a negative electrode sheet, which are stacked and spaced apart to form a gap, and at least part of the electrolyte is contained in the gap.

[0058] Taking a lithium-ion battery cell as an example, during the discharge process of a lithium-ion battery cell, the lithium ions in the negative electrode sheet are ionized and separated from the electrons, and the lithium ions pass from the negative electrode sheet to the positive electrode sheet through the electrolyte and recombine with the electrons on the positive electrode sheet. During the charging process of a lithium-ion battery cell, lithium ions are generated on the positive electrode sheet, and the lithium ions move to the negative electrode sheet through the electrolyte and are embedded in the negative electrode sheet.

[0059] However, in the related art, during the charging process of lithium-ion battery cells, the electrode assembly will expand, and the expanded electrode assembly will squeeze out the electrolyte in the gap of the electrode assembly, resulting in a lack of electrolyte in certain parts of the electrode assembly. In the case of a lack of electrolyte in certain parts of the negative electrode sheet of the electrode assembly, lithium ions cannot be embedded in the negative electrode sheet and metal lithium dendrites are formed on the surface of the negative electrode sheet. This phenomenon is called lithium precipitation. The lithium precipitation phenomenon will cause the capacity of the battery cell to decrease. The precipitated metal lithium dendrites may pierce the separator of the electrode assembly, causing a short circuit between the positive and negative electrode sheets, which will have a serious adverse effect on the performance of the battery cell.

[0060] In order to reduce the risk of metal dendrites precipitating from the battery cell and improve the performance of the battery cell, the blocking member in the battery cell provided in the embodiment of the present application is covered on the slit of the electrode assembly. In this way, during the charging process of the battery cell, even if the electrode assembly expands, the blocking action of the blocking member can effectively prevent the electrolyte from escaping from the gap through the slit, effectively improving the situation of lack of electrolyte in certain parts of the electrode assembly, thereby effectively reducing the risk of metal dendrites precipitating from the electrode assembly and effectively improving the performance of the battery cell.

[0061] The battery disclosed in the embodiment of the present application can be used for electrical equipment using the battery as a power source, or for various energy storage systems using the battery as an energy storage element. Electrical equipment can be, but is not limited to, vehicles, mobile phones, portable devices, laptops, ships, spacecraft, electric toys, and electric tools, etc. The vehicle can be a fuel vehicle, a gas vehicle, or a new energy vehicle, and the new energy vehicle can be a pure electric vehicle, a hybrid vehicle, or an extended-range vehicle, etc. Spacecraft include airplanes, rockets, space shuttles, and spacecraft, etc. Electric toys include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc. Electric tools include metal cutting electric tools, grinding electric tools, assembly electric tools, and railway electric tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers, etc.

[0062] For the convenience of description, the following embodiments are described by taking a vehicle as an example of an electrical device in an embodiment of the present application.

[0063] See also Figure 1 , Figure 1 A schematic diagram of the structure of a vehicle 1000 provided in an embodiment of the present application. A battery 100 is provided inside the vehicle 1000, and the battery 100 can be provided at the bottom, head, or tail of the vehicle 1000. The battery 100 can be used to power the vehicle 1000, for example, the battery 100 can be used as an operating power source for the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300, and the controller 200 is used to control the battery 100 to power the motor 300, for example, for starting, navigating, and driving the vehicle 1000.

[0064] In some embodiments of the present application, the battery 100 can not only serve as an operating power source for the vehicle 1000, but also serve as a driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0065] See also Figure 2 , Figure 2Schematic diagram of an explosion of a battery 100 provided in an embodiment of the present application. The battery 100 includes a housing 10 and a battery cell 20, and the battery cell 20 is contained in the housing 10. The housing 10 is used to provide a storage space for the battery cell 20, and the housing 10 can adopt a variety of structures. In some embodiments, the housing 10 can include a first part 11 and a second part 12, and the first part 11 and the second part 12 cover each other, and the first part 11 and the second part 12 jointly define a storage space for accommodating the battery cell 20. The second part 12 can be a hollow structure with one end open, and the first part 11 can be a plate-like structure, and the first part 11 is covered on the open side of the second part 12, so that the first part 11 and the second part 12 jointly define a storage space; the first part 11 and the second part 12 can also be hollow structures with one side open, and the open side of the first part 11 is covered on the open side of the second part 12. Of course, the housing 10 formed by the first part 11 and the second part 12 can be in a variety of shapes, such as a cylinder, a cuboid, etc.

[0066] Of course, in some embodiments, the battery 100 may not include the housing 10 , but rather a plurality of battery cells 20 may be electrically connected and formed into a whole through necessary fixing structures and then assembled into the vehicle 1000 .

[0067] In the battery 100, there may be multiple battery cells 20, and the multiple battery cells 20 may be connected in series, in parallel, or in a mixed connection. A mixed connection means that the multiple battery cells 20 are both connected in series and in parallel. The multiple battery cells 20 may be directly connected in series, in parallel, or in a mixed connection, and then the whole formed by the multiple battery cells 20 is accommodated in the box 10. Of course, the battery 100 may also be a battery module formed by first connecting multiple battery cells 20 in series, in parallel, or in a mixed connection, and then the multiple battery modules are connected in series, in parallel, or in a mixed connection to form a whole, and then accommodated in the box 10.

[0068] Each battery cell 20 may be a secondary battery or a primary battery, wherein a secondary battery refers to a battery cell 20 that can be used continuously by activating the active material by charging after the battery cell 20 is discharged, and a primary battery refers to a battery cell 20 that cannot be used continuously by activating the active material by charging after the power of the battery cell 20 is exhausted; the battery cell 20 may also be a lithium ion battery, a sodium ion battery, a sodium lithium ion battery, a lithium metal battery, a sodium metal battery, a lithium sulfur battery, a magnesium ion battery, a nickel hydrogen battery, a nickel cadmium battery, a lead storage battery, etc., but is not limited thereto. The battery cell 20 may be a cylindrical battery cell, a prismatic battery cell, a soft pack battery cell, or a battery cell of other shapes, wherein the prismatic battery cell includes a square shell battery cell, a blade-shaped battery cell, and a multi-prismatic battery cell, wherein the multi-prismatic battery cell is, for example, a hexagonal battery cell, etc., and the present application has no particular restrictions.

[0069] In order to illustrate the technical solution provided by the present application, a detailed description is given below in conjunction with specific drawings and embodiments.

[0070] First, please also refer to Figures 3 to 7 The embodiment of the present application provides a battery cell 20, including a housing 21, an electrode assembly 22, an electrolyte and a barrier 23. The housing 21 has a cavity 213, and the electrode assembly 22 is accommodated in the cavity 213. The electrode assembly 22 includes a first pole piece 221 and a second pole piece 222 with opposite polarities, and the first pole piece 221 and the second pole piece 222 are stacked and spaced to form a gap 223, and the gap 223 penetrates the outer side of the electrode assembly 22 to form a gap. The electrolyte is accommodated in the gap 223, and the barrier 23 is covered at the gap to prevent the electrolyte from escaping from the gap 223 through the gap.

[0071] The shell 21 is a component for providing a space for accommodating components such as the electrode assembly 22 and the electrolyte. The shell 21 may include a shell 211 and an end cap 212. Among them, the shell 211 is a component for providing an internal environment of the battery cell 20, and the internal environment can be used to accommodate components such as the electrode assembly 22 and the electrolyte. The shell 211 can be an independent component, and an opening can be set on the shell 211. By covering the end cap 212 on the opening to close the internal environment of the battery cell 20, the electrode assembly 22, the electrolyte and other components are accommodated in the internal environment. Specifically, the shell 211 and the end cap 212 can form a common connection surface before other components are put into the shell, and when the interior of the shell 211 needs to be encapsulated, the end cap 212 is covered on the opening of the shell 211. The shape of the shell 211 can be, but not limited to, a rectangular parallelepiped, a cylindrical shape, a hexagonal prism, etc. The material of the shell 211 can be, but not limited to, copper, iron, aluminum, stainless steel, aluminum alloy, etc.

[0072] The end cap 212 refers to a component that is covered at the opening of the shell 211 to isolate the internal environment of the battery cell 20 from the external environment. The shape of the end cap 212 can be adapted to the shape of the shell 211 to match the shell 211. In some embodiments, the end cap 212 can be made of a material with a certain hardness and strength, so that the end cap 212 is not easily deformed when squeezed and collided, so that the battery cell 20 can have a higher structural strength and the safety performance can also be improved. The material of the end cap 212 can be, but is not limited to, copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc.

[0073] The electrode assembly 22 is a component in the battery cell 20 where an electrochemical reaction occurs. The battery cell 20 may include one or more electrode assemblies 22. The main body of the electrode assembly 22 is made of a positive electrode sheet, a negative electrode sheet and a separator by a winding process or a stacking process, wherein one of the first electrode sheet 221 and the second electrode sheet 222 is a positive electrode sheet, and the other of the first electrode sheet 221 and the second electrode sheet 222 is a negative electrode sheet. There may be multiple positive electrode sheets and multiple negative electrode sheets, respectively, and multiple positive electrode sheets and multiple negative electrode sheets are alternately stacked. A gap 223 is formed between adjacent positive electrode sheets and negative electrode sheets, and the gap 223 penetrates the outer side of the electrode assembly 22 to form a slit, and the gap 223 is connected to the above-mentioned cavity 213 through the slit. The separator is arranged in the gap 223 to insulate and separate the positive electrode sheet and the negative electrode sheet. In some embodiments, there may be multiple positive electrode sheets, and the negative electrode sheet is folded to form multiple stacked folded sections, and a positive electrode sheet is clamped between adjacent folded sections. In other embodiments, both the positive electrode sheet and the negative electrode sheet are folded to form a plurality of folded sections stacked in layers. In some embodiments, a plurality of separators may be provided, respectively disposed between any adjacent positive electrode sheets or negative electrode sheets. In other embodiments, the separators may be provided continuously, and disposed between any adjacent positive electrode sheets or negative electrode sheets by folding or winding. The shape of the electrode assembly 22 may be, but is not limited to, cylindrical, flat, or multi-prism-shaped, etc. In some embodiments, the electrode assembly 22 further includes a pole ear 224, and the pole ear 224 includes a positive pole ear and a negative pole ear, the positive pole ear is connected to the positive electrode sheet, and the negative pole ear is connected to the negative electrode sheet, so as to derive the current of the electrode assembly 22 or input the current into the electrode assembly 22.

[0074] During the charge and discharge process of the battery cell 20, active ions (such as lithium ions) are inserted and removed between the positive and negative electrodes. The separator is arranged between the positive and negative electrodes to prevent the positive and negative electrodes from short-circuiting and to allow the active ions to pass through.

[0075] The positive electrode sheet may include a positive electrode current collector and a positive electrode active material disposed on at least one surface of the positive electrode current collector. In some embodiments, the positive electrode current collector has two surfaces opposite to each other in its thickness direction, and the positive electrode active material is disposed on either or both of the two opposite surfaces of the positive electrode current collector.

[0076] As an example, the positive electrode current collector may be a metal foil, a composite current collector or a foamed metal. For example, as a metal foil, aluminum or stainless steel, stainless steel, copper, aluminum, nickel, carbon electrode, carbon, nickel or titanium with a silver surface treatment may be used. The composite current collector may include a polymer material base and a metal layer. The composite current collector may be formed by forming a metal material (aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.). The foamed metal may be a nickel foam, a copper foam, an aluminum foam, a foamed alloy, or a carbon foam, etc. When the foamed metal is used as the positive electrode, the positive electrode active material may not be provided on the surface of the foamed metal, but of course, the positive electrode active material may also be provided. As an example, a lithium source material, potassium metal or sodium metal may also be filled or / and deposited in the foamed metal, and the lithium source material is a lithium metal and / or a lithium-rich material.

[0077] As an example, the positive electrode active material may include at least one of the following materials: lithium-containing phosphates, lithium transition metal oxides, and their respective modified compounds. However, the present application is not limited to these materials, and other traditional materials that can be used as positive electrode active materials for battery cells 20 may also be used. These positive electrode active materials may be used alone or in combination of two or more. Examples of lithium-containing phosphates may include, but are not limited to, lithium iron phosphate (such as LiFePO 4 (also referred to as LFP), composite materials of lithium iron phosphate and carbon, lithium manganese phosphate (such as LiMnPO 4 ), a composite material of lithium manganese phosphate and carbon, lithium iron manganese phosphate, and a composite material of lithium iron manganese phosphate and carbon. Examples of lithium transition metal oxides may include but are not limited to lithium cobalt oxide (such as LiCoO 2 ), lithium nickel oxide (such as LiNiO 2 ), lithium manganese oxide (such as LiMnO 2 、LiMn 2 O 2 ), lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, lithium nickel cobalt manganese oxide (such as LiNi1 / 3Co1 / 3Mn1 / 3O 2 (also referred to as NCM333), LiNi0.5Co0.2Mn0.3O 2 (also referred to as NCM523), LiNi0.5Co0.25Mn0.25O 2 (also referred to as NCM211), LiNi0.6Co0.2Mn0.2O 2 (also referred to as NCM622), LiNi0.8Co0.1Mn0.1O 2(also referred to as NCM811), lithium nickel cobalt aluminum oxide (such as LiNi0.85Co0.15Al0.05O 2 ) and at least one of its modified compounds.

[0078] The negative electrode sheet may include a negative electrode current collector and a negative electrode active material disposed on at least one surface of the negative electrode current collector. In some embodiments, the negative electrode current collector has two surfaces opposite to each other in its thickness direction, and the negative electrode active material is disposed on any one or both of the two opposite surfaces of the negative electrode current collector.

[0079] As an example, the negative electrode current collector can be a metal foil, a composite current collector or a foamed metal. For example, as a metal foil, aluminum or stainless steel, stainless steel, copper, aluminum, nickel, carbon electrode, carbon, nickel or titanium, etc., treated with silver surface, can be used. The composite current collector may include a polymer material base and a metal layer. The composite current collector may be formed by forming a metal material (copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.). The foamed metal may be a nickel foam, a copper foam, an aluminum foam, an alloy foam, or a carbon foam, etc.

[0080] As an example, the negative electrode active material may adopt the negative electrode active material for the battery cell 20 known in the art. As an example, the negative electrode active material may include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, lithium titanate, etc. The silicon-based material may be selected from at least one of elemental silicon, silicon oxide compounds, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. The tin-based material may be selected from at least one of elemental tin, tin oxide compounds, and tin alloys. However, the present application is not limited to these materials, and other traditional materials that can be used as negative electrode active materials for the battery cell 20 may also be used. These negative electrode active materials may be used alone or in combination of two or more.

[0081] In some embodiments, the material of the positive electrode current collector may be aluminum, and the material of the negative electrode current collector may be copper.

[0082] In some embodiments, the separator is a separator. The present application has no particular restrictions on the type of separator, and any known porous structure separator with good chemical stability and mechanical stability can be selected. For example, the material of the separator can be but is not limited to glass fiber, non-woven fabric, polyethylene, polypropylene, polyvinylidene fluoride and ceramics. The separator can be a single-layer film or a multi-layer composite film. In the case where the separator is a multi-layer composite film, the materials of each layer of the separator can be the same or different. The separator can be a separate component located between the positive electrode sheet and the negative electrode sheet, or it can be attached to the surface of the positive electrode sheet and the surface of the negative electrode sheet.

[0083] The electrolyte plays the role of conducting ions between the positive electrode sheet and the negative electrode sheet. A portion of the electrolyte is contained in the gap 223 of the electrode assembly 22, and another portion of the electrolyte is disposed outside the electrode assembly 22, so that at least a portion of the electrode assembly 22 is immersed in the electrolyte. The present application has no specific restrictions on the type of electrolyte, which can be selected according to needs. In some embodiments, the electrolyte can be a liquid electrolyte. Of course, in other embodiments, the electrolyte can also be a gel electrolyte, a solid electrolyte, etc.

[0084] The blocking member 23 is used to cover at least part of the slit of the slit 223 to prevent the electrolyte from escaping from the slit 223 of the electrode assembly 22. The blocking member 23 may cover the entire slit of the slit 223, or may only cover a part of the slit of the slit 223. In the case where the number of positive electrode sheets and the number of negative electrode sheets are both multiple, adjacent positive electrode sheets and negative electrode sheets are spaced to form a slit 223, and the blocking member 23 is covered at the slits of the multiple slits 223. In some embodiments, the blocking member 23 covers the outside of the electrode assembly 22 and is fixedly connected to the electrode assembly 22 to reduce the risk of displacement of the blocking member 23 relative to the electrode assembly 22. The connection method between the blocking member 23 and the electrode assembly 22 may be, but is not limited to, bonding, welding, etc. The blocking member 23 may be a film-like structure or a plate-like structure. In some embodiments, the slit may be completely closed by the blocking member 23, that is, the electrolyte cannot pass through the blocking member 23 to reach the outside of the slit 223. In other embodiments, the barrier 23 may also have a certain permeability, that is, part of the electrolyte can pass through the barrier 23 to the outside of the gap 223. The material of the barrier 23 may be, but is not limited to, glass fiber, non-woven fabric, polyethylene, polypropylene, polyvinylidene fluoride, and ceramics. In some embodiments, the material of the barrier 23 is the same as that of the above-mentioned separator.

[0085] In some embodiments, the battery cell 20 further includes an electrode terminal 25, which is a component electrically connected to the electrode assembly 22 for outputting or inputting electrical energy. The electrode terminal 25 can be arranged in the electrode lead-out hole of the end cap 212, a part of the electrode terminal 25 is arranged in the internal environment of the battery cell 20 and is directly or indirectly connected to the pole ear 224 of the electrode assembly 22, and another part of the electrode terminal 25 is arranged in the external environment of the battery cell 20 and is connected to the converging component, the sampling device and other components. The number of electrode terminals 25 can be two, and the two electrode terminals 25 are respectively arranged on opposite sides of the end cap 212. Optionally, the electrode terminal 25 can be a columnar structure, such as a cylindrical structure, a prismatic structure, etc., and the electrode terminal 25 can also be a plate-like structure, such as a circular plate, a square plate, etc. Of course, in other embodiments, the electrode terminal 25 can also be other irregular three-dimensional structures. The electrode terminal 25 can be made of one metal material or a plurality of metal materials. The metal material can be but is not limited to copper, aluminum, nickel, zinc, iron, etc.

[0086] In some embodiments, the battery cell 20 further includes a pressure relief mechanism, which is a mechanism for releasing the internal pressure when the internal pressure or temperature of the battery cell 20 reaches a threshold value. The pressure relief mechanism can be installed on the end cover 212 or on the housing 211. In the case where the pressure relief mechanism is installed on the end cover 212, the pressure relief mechanism is arranged between the two electrode terminals 25. In the case where the pressure relief mechanism is installed on the housing 211, the pressure relief mechanism can be installed on the wall of the housing 211 opposite to the end cover 212.

[0087] In some embodiments, the main body of the electrode assembly 22 is made of a positive electrode sheet, a negative electrode sheet and a separator by a lamination process. The positive electrode ear and the negative electrode ear are arranged on opposite sides of the main body of the electrode assembly 22, and the shell 211 has two openings, the positive electrode ear is arranged opposite to one opening, and the negative electrode ear is arranged opposite to the other opening. There are two end caps 212, one end cap 212 is arranged to cover one opening, and the other end cap 212 is arranged to cover the other opening. The blocking member 23 is arranged on the main body of the electrode assembly 22 and is located between the positive electrode ear and the negative electrode ear.

[0088] In other embodiments, the main body of the electrode assembly 22 is made of a positive electrode sheet, a negative electrode sheet and a separator by a lamination process. The positive electrode ear and the negative electrode ear are arranged on the same side of the main body of the electrode assembly 22, and the positive electrode ear and the negative electrode ear are arranged opposite to the opening of the shell 211, the end cover 212 is covered on the opening, and the blocking member 23 is covered on the main body of the electrode assembly 22 and is located between the positive electrode ear and the negative electrode ear.

[0089] In some other embodiments, the main body of the electrode assembly 22 is made of a positive electrode sheet, a negative electrode sheet and a separator by a winding process. The positive electrode ear and the negative electrode ear are arranged on the same side of the main body of the electrode assembly 22, and the positive electrode ear and the negative electrode ear are arranged opposite to the opening of the shell 211, the end cover 212 is covered on the opening, and the blocking member 23 is covered on the main body of the electrode assembly 22 and is located between the positive electrode ear and the negative electrode ear.

[0090] The blocking member 23 in the battery cell 20 provided in the embodiment of the present application is covered on the slit of the electrode assembly 22. In this way, during the charging process of the battery cell 20, even if the electrode assembly 22 expands, the blocking effect of the blocking member 23 can effectively prevent the electrolyte from escaping from the gap 223 through the slit, thereby effectively improving the situation where certain parts of the electrode assembly 22 lack electrolyte, thereby effectively reducing the risk of metal dendrites precipitating from the electrode assembly 22, and effectively improving the performance of the battery cell 20.

[0091] In some embodiments of this application, please refer to Figures 4 to 7 The shell 21 includes a first wall 2111 for supporting the electrode assembly 22, the blocking member 23 includes a first blocking portion 231, the gap 223 penetrates the side of the electrode assembly 22 away from the first wall 2111 to form a first slit 2231, and the first blocking portion 231 covers at least a portion of the first slit 2231.

[0092] The first wall 2111 is a wall portion for providing support force for the electrode assembly 22. It can be understood that when the battery cell 20 is placed on any supporting surface, the first wall 2111 refers to the wall portion of the housing 21 that is arranged opposite to the supporting surface. In some embodiments, the first wall 2111 is the bottom wall of the housing 211, and the electrode assembly 22 is placed on the first wall 2111. In other words, the side of the electrode assembly 22 facing away from the first wall 2111 is the top side of the electrode assembly 22. In some embodiments, the housing 21 also includes a second wall and a third wall, the second wall is arranged opposite to the first wall 2111, and the third wall is connected between the first wall 2111 and the second wall, and the first wall 2111, the second wall and the third wall together define the above-mentioned cavity 213.

[0093] The first slit 2231 is a portion of the slit formed on the side of the electrode assembly 22 away from the first wall 2111. The first blocking portion 231 is used to cover at least a portion of the first slit 2231 of the slit 223 to prevent the electrolyte from escaping from the slit 223 of the electrode assembly 22. The first blocking portion 231 may cover the entire first slit 2231 or only a portion of the first slit 2231.

[0094] In the related art, when the electrolyte is a liquid electrolyte, the internal environment of the battery cell 20 usually needs to reserve free space, that is, the internal environment of the battery cell 20 will not be filled with liquid electrolyte. In this way, the top side of the electrode assembly 22 can only be just soaked by the liquid electrolyte or even exposed outside the liquid electrolyte. Therefore, compared with other parts of the electrode assembly 22, during the charging process of the battery cell 20, the top side of the electrode assembly 22 is more likely to lack electrolyte, which makes it easier for metal dendrites to precipitate on the top side of the electrode assembly 22.

[0095] By adopting the above technical solution, the situation of lack of electrolyte on the top side of the electrode assembly 22 is effectively improved, thereby effectively reducing the risk of metal dendrites precipitating from the electrode assembly 22 and effectively improving the performance of the battery cell 20.

[0096] In some embodiments of this application, please refer to Figure 5 and Figure 6 The blocking member 23 also includes two second blocking portions 232, which are respectively arranged on opposite sides of the first blocking portion 231 along the width direction of the battery cell 20, and the gap 223 penetrates the opposite sides of the electrode assembly 22 along the width direction of the battery cell 20 to form a second slit 2232, and the second blocking portion 232 covers at least part of the second slit 2232.

[0097] In this embodiment, the electrode assembly 22 is made of positive electrode sheets, negative electrode sheets and separators by a stacking process, and the direction perpendicular to the stacking direction of the positive electrode sheets, negative electrode sheets and separators and perpendicular to the first wall 2111 is defined as the height direction of the battery cell 20, such as Figures 4 to 7 The Z direction shown in FIG. 1 is defined as the width direction of the battery cell 20, which is perpendicular to the stacking direction of the positive electrode sheet, the negative electrode sheet and the separator and the height direction of the battery cell 20. Figures 4 to 7 The X direction shown in FIG. 1 is a direction perpendicular to the height direction and the width direction of the battery cell 20 and is defined as the thickness direction of the battery cell 20. Figures 4 to 7 In the Y direction shown, the dimension of the battery cell 20 along the width direction may be the same as or different from the dimension of the battery cell 20 along the thickness direction.

[0098] The slit forms the circumference of the electrode assembly 22, wherein the second slit 2232 is a portion of the slit formed on the opposite sides of the electrode assembly 22 along the width direction of the battery cell 20, and the first slit 2231 is a portion of the slit formed on the top side of the electrode assembly 22. The second blocking portion 232 is used to cover at least a portion of the second slit 2232 of the slit 223 to prevent the electrolyte from escaping from the slit 223 of the electrode assembly 22. The second blocking portion 232 may cover the entirety of the second slit 2232, or may only cover a portion of the second slit 2232. In some embodiments, the second blocking portion 232 covers a portion of the second slit 2232 close to the top side of the electrode assembly 22. The two second blocking portions 232 are disposed on opposite sides of the first blocking portion 231 along the width direction of the battery cell 20, and the second blocking portion 232 and the first blocking portion 231 may be integrally formed components, or the second blocking portion 232 and the first blocking portion 231 may be separately formed and then connected into a whole.

[0099] By adopting the above technical solution, the situation of lack of electrolyte on the top side of the electrode assembly 22 is further improved, thereby further reducing the risk of metal dendrite precipitation in the electrode assembly 22 and further improving the performance of the battery cell 20.

[0100] In some embodiments of this application, please refer to Figure 6 and Figure 7 The first electrode sheet 221 is a negative electrode sheet, and the blocking member 23 includes a liquid absorbing portion 233 , which is attached to the surface of the first electrode sheet 221 along the thickness direction.

[0101] In the case where the electrolyte is a liquid electrolyte, the liquid absorption portion 233 can absorb the liquid electrolyte. During the charging process of the battery cell 20, the electrode assembly 22 expands, and the liquid electrolyte is squeezed out of the gap 223 of the electrode assembly 22, so that a metal dendrite precipitation region is formed on the surface of the first pole piece 221. The liquid absorption portion 233 is attached to the surface of the first pole piece 221 along the thickness direction. It can be understood that the liquid absorption portion 233 covers at least part of the above-mentioned metal dendrite precipitation region, and the liquid electrolyte absorbed by the liquid absorption portion 233 can be supplemented to the metal dendrite precipitation region of the above-mentioned first pole piece 221 to alleviate the situation of metal dendrite precipitation of the electrode assembly 22. In some embodiments, the liquid absorption portion 233 covers all of the above-mentioned metal dendrite precipitation region. In other words, the size of the liquid absorption portion 233 along the width direction of the battery cell 20 is greater than the size of the metal dendrite precipitation region along the width direction of the battery cell 20, and the size of the liquid absorption portion 233 along the height direction of the battery cell 20 is greater than the size of the metal dendrite precipitation region along the height direction of the battery cell 20.

[0102] In some embodiments, the liquid absorption portion 233 is provided with a plurality of liquid absorption pores so that the liquid absorption portion 233 has a certain capillary effect. When the liquid electrolyte is squeezed out of the gap 223 of the electrode assembly 22, the liquid absorption portion 233 can absorb the liquid electrolyte through the liquid absorption pores and replenish the liquid electrolyte to the metal dendrite precipitation area of ​​the first electrode piece 221 to alleviate the situation of metal dendrite precipitation in the electrode assembly 22.

[0103] In some embodiments, the electrode assembly 22 is formed of the first pole piece 221 on both sides thereof along the thickness direction of the battery cell 20. In other words, the two large surfaces of the electrode assembly 22 on the thickness direction of the battery cell 20 are formed of the surface of the first pole piece 221. There are two liquid absorption portions 233. The two liquid absorption portions 233 are arranged on both sides thereof along the thickness direction of the battery cell 20. One liquid absorption portion 233 is attached to the surface of the first pole piece 221 on one side of the electrode assembly 22 in the thickness direction of the battery cell 20, and the other liquid absorption portion 233 is attached to the surface of the first pole piece 221 on the other side of the electrode assembly 22 in the thickness direction of the battery cell 20.

[0104] Of course, in other embodiments, one side of the electrode assembly 22 along the thickness direction of the battery cell 20 may be composed of a first pole piece 221, and the other side of the electrode assembly 22 along the thickness direction of the battery cell 20 may be composed of a second pole piece 222, and the number of the liquid absorption parts 233 is two, and the two liquid absorption parts 233 are arranged on the opposite sides of the above-mentioned first blocking part 231 along the thickness direction of the battery cell 20, one liquid absorption part 233 is attached to the surface of the first pole piece 221 located on one side of the electrode assembly 22 along the thickness direction of the battery cell 20, and the other liquid absorption part 233 is attached to the surface of the second pole piece 222 located on the other side of the electrode assembly 22 along the thickness direction of the battery cell 20.

[0105] By adopting the above technical solution, the liquid absorption portion 233 can absorb the electrolyte located outside the electrode assembly 22 and replenish the electrolyte to the surface of the first electrode plate 221, thereby alleviating the precipitation of metal dendrites in the electrode assembly 22 and improving the performance of the battery cell 20.

[0106] In some embodiments of this application, please refer to Figure 6 and Figure 7 The blocking member 23 is provided with an exhaust hole 234 .

[0107] The exhaust pores 234 are hole structures for providing an exhaust channel for gas. The number of the exhaust pores 234 can be multiple, and the multiple exhaust pores 234 are evenly distributed on the surface of the blocking member 23.

[0108] In some embodiments, the blocking member 23 includes a first blocking portion 231 . The first blocking portion 231 is provided with a plurality of exhaust pores 234 . The exhaust pores 234 are evenly distributed on the surface of the first blocking portion 231 .

[0109] In other embodiments, the blocking member 23 includes a first blocking portion 231 and a second blocking portion 232 , each of which is provided with a plurality of exhaust pores 234 , and the exhaust pores 234 are evenly distributed on the surface of the first blocking portion 231 and the surface of the second blocking portion 232 .

[0110] In some other embodiments, the blocking member 23 includes a first blocking portion 231, a second blocking portion 232 and a liquid absorption portion 233, and the first blocking portion 231, the second blocking portion 232 and the liquid absorption portion 233 are all provided with a plurality of exhaust pores 234, and the exhaust pores 234 are evenly distributed on the surface of the first blocking portion 231, the surface of the second blocking portion 232 and the surface of the liquid absorption portion 233.

[0111] By adopting the above-mentioned technical solution, not only can the electrolyte be prevented from escaping from the gap 223 through the gap, but the gas generated by the electrode assembly 22 during the charging and discharging process can be discharged to the outside of the electrode assembly 22 through the exhaust pores 234, so as to alleviate the expansion of the electrode assembly 22, and further improve the situation where certain parts of the electrode assembly 22 lack electrolyte, thereby further reducing the risk of metal dendrite precipitation in the electrode assembly 22, and further improving the performance of the battery cell 20.

[0112] In addition, by opening the exhaust pores 234 on the blocking member 23, the blocking member 23 can also have a certain capillary effect. When the liquid electrolyte is squeezed out of the gap 223 of the electrode assembly 22, the blocking member 23 can absorb the liquid electrolyte through the exhaust pores 234 and replenish the liquid electrolyte into the gap 223 of the electrode assembly 22 to alleviate the precipitation of metal dendrites in the electrode assembly 22.

[0113] In some embodiments of the present application, the porosity of the barrier 23 is 25%-50%.

[0114] The porosity of the blocking member 23 may be determined according to actual application requirements, and may specifically be 25%, 30%, 35%, 40%, 45%, 50%, etc.

[0115] By adopting the above technical solution, not only can the blocking member 23 effectively prevent the electrolyte from escaping from the gap 223 through the gap, but also the gas generated by the electrode assembly 22 during the charging and discharging process can be discharged to the outside of the electrode assembly 22 through the exhaust pores 234, thereby effectively alleviating the expansion of the electrode assembly 22.

[0116] In some embodiments of the present application, there are multiple blocking members 23, and the multiple blocking members 23 are stacked.

[0117] In some embodiments, the number of the blocking members 23 is two, and the two blocking members 23 are stacked and cover the opening of the slit 223 of the electrode assembly 22 .

[0118] By adopting the above-mentioned technical solution, under the premise that the gas generated by the electrode assembly 22 can be discharged to the outside of the electrode assembly 22 through the exhaust pores 234, it can more effectively prevent the electrolyte from escaping from the gap 223 through the gap, thereby further improving the situation where certain parts of the electrode assembly 22 lack electrolyte, thereby further reducing the risk of metal dendrites precipitating in the electrode assembly 22, and further improving the performance of the battery cell 20.

[0119] In some embodiments of the present application, the porosity of the plurality of barriers 23 gradually decreases in a direction away from the electrode assembly 22 .

[0120] In other words, the closer the blocking member 23 is to the outside of the electrode assembly 22 , the greater the porosity of the blocking member 23 , and the farther the blocking member 23 is from the outside of the electrode assembly 22 , the smaller the porosity of the blocking member 23 .

[0121] In some embodiments, there are two blocking members 23 , the first blocking member 23 is attached to the outer side of the electrode assembly 22 , and the second blocking member 23 is attached to the surface of the first blocking member 23 facing away from the electrode assembly 22 , and the porosity of the first blocking member 23 is greater than the porosity of the second blocking member 23 .

[0122] By adopting the above technical solution, not only can the electrolyte be effectively prevented from escaping from the gap 223 through the slit, but it is also beneficial for the blocking member 23 to reabsorb the electrolyte. The electrolyte reabsorbed by the blocking member 23 can be replenished into the gap 223 of the electrode assembly 22, further improving the situation where certain parts of the electrode assembly 22 lack electrolyte, thereby further reducing the risk of metal dendrites precipitating in the electrode assembly 22, and further improving the performance of the battery cell 20.

[0123] In some embodiments of the present application, the blocking member 23 is a film member, and the blocking member 23 is attached to the outer side of the electrode assembly 22 .

[0124] In other words, in this embodiment, the blocking member 23 is a film-like structure. In some embodiments, the material of the blocking member 23 is the same as the material of the above-mentioned isolation member.

[0125] By adopting the above technical solution, the space occupied by the blocking member 23 is effectively reduced, thereby effectively improving the volume energy density of the battery cell 20.

[0126] In some embodiments of this application, please refer to Figure 6The battery cell 20 further includes a connecting member 24 , and the blocking member 23 is fixedly connected to the electrode assembly 22 via the connecting member 24 .

[0127] The connector 24 is a component for connecting the blocking member 23 and the electrode assembly 22. The number of the connector 24 can be one or more. In some embodiments, the connector 24 is connected between the side of the blocking member 23 and the surface of the electrode assembly 22. The connector 24 can be, but is not limited to, an adhesive, a binding tape, etc.

[0128] By adopting the above technical solution, the blocking member 23 is effectively fixed on the electrode assembly 22 .

[0129] In some embodiments of the present application, the connecting member 24 is an adhesive member.

[0130] In other words, the blocking member 23 is bonded to the electrode assembly 22 through the connecting member 24 .

[0131] By adopting the above technical solution, it is convenient to fix the blocking member 23 on the electrode assembly 22, thereby effectively improving the production efficiency of the battery cell 20.

[0132] In some embodiments of this application, please refer to Figure 7 The blocking member 23 includes a connecting portion 235 , and the connecting portion 235 is fixedly connected to the electrode assembly 22 .

[0133] The connection portion 235 is a portion for connecting the electrode assembly 22. The number of the connection portion 235 may be one or more.

[0134] In some embodiments, the blocking member 23 includes a first blocking portion 231, a liquid absorption portion 233 and a connecting portion 235, wherein the liquid absorption portion 233 is connected to the side of the first blocking portion 231, the connecting portion 235 is connected to the side of the liquid absorption portion 233 facing away from the first blocking portion 231, and the connecting portion 235 is connected to the surface of the electrode assembly 22.

[0135] In other embodiments, the blocking member 23 includes a first blocking portion 231, a second blocking portion 232, a liquid absorption portion 233 and a connecting portion 235, the second blocking portion 232 is connected to one side of the first blocking portion 231 along the width direction of the battery cell 20, the liquid absorption portion 233 is connected to one side of the first blocking portion 231 along the thickness direction of the battery cell 20, the number of the connecting portions 235 is multiple, at least one connecting portion 235 is connected to the side of the second blocking portion 232 facing away from the first blocking portion 231, at least another connecting portion 235 is connected to the side of the liquid absorption portion 233 facing away from the first blocking portion 231, and each connecting portion 235 is connected to the surface of the electrode assembly 22.

[0136] By adopting the above technical solution, the blocking member 23 is effectively fixed on the electrode assembly 22 .

[0137] In some embodiments of the present application, the connecting portion 235 is an adhesive portion.

[0138] By adopting the above technical solution, it is convenient to fix the blocking member 23 on the electrode assembly 22, thereby effectively improving the production efficiency of the battery cell 20.

[0139] Second, see Figure 2 , an embodiment of the present application provides a battery 100, comprising the battery cell 20 described in any of the above embodiments.

[0140] The battery 100 provided in the embodiment of the present application adopts the battery cell 20 described in any of the above embodiments, thereby effectively improving the performance of the battery 100.

[0141] Third, see Figure 1 , an embodiment of the present application provides an electrical device, including the above-mentioned battery 100.

[0142] The electric device provided in the embodiment of the present application adopts the above-mentioned battery 100, thereby effectively improving the performance of the electric device.

[0143] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A battery cell, characterized in that: include: A housing having a cavity; An electrode assembly is accommodated in the cavity, the electrode assembly comprising a first electrode sheet and a second electrode sheet with opposite polarities, the first electrode sheet and the second electrode sheet are stacked and spaced to form a gap, and the gap penetrates the outer side of the electrode assembly to form a seam; an electrolyte, contained in the gap; The blocking member is arranged to cover the slit to prevent the electrolyte from escaping from the gap through the slit.

2. The battery cell according to claim 1, characterized in that: The shell includes a first wall for supporting the electrode assembly, the blocking member includes a first blocking portion, the gap passes through a side of the electrode assembly away from the first wall to form a first slit, and the first blocking portion covers at least a portion of the first slit.

3. The battery cell according to claim 2, characterized in that: The blocking member also includes two second blocking portions, which are arranged on opposite sides of the first blocking portion along the width direction of the battery cell, and the gap penetrates the opposite sides of the electrode assembly along the width direction of the battery cell to form a second slit, and the second blocking portion covers at least part of the second slit.

4. The battery cell according to claim 1, characterized in that: The first pole piece is a negative pole piece, and the blocking member includes a liquid absorbing portion, which is attached to a surface of the first pole piece along a thickness direction.

5. The battery cell according to claim 1, characterized in that: The blocking member is provided with an exhaust hole.

6. The battery cell according to claim 5, characterized in that: The porosity of the barrier is 25%-50%.

7. The battery cell according to claim 6, characterized in that: There are multiple blocking members, and the multiple blocking members are stacked.

8. The battery cell according to claim 7, characterized in that: The porosity of the plurality of barrier members gradually decreases in a direction away from the electrode assembly.

9. The battery cell according to any one of claims 1 to 8, characterized in that: The blocking member is a film member, and the blocking member is attached to the outer side of the electrode assembly.

10. The battery cell according to any one of claims 1 to 8, characterized in that: The battery cell further includes a connecting member, and the blocking member is fixedly connected to the electrode assembly through the connecting member.

11. The battery cell according to claim 10, characterized in that: The connecting member is an adhesive member.

12. The battery cell according to any one of claims 1 to 8, characterized in that: The blocking member includes a connecting portion, and the connecting portion is fixedly connected to the electrode assembly.

13. The battery cell according to claim 12, characterized in that: The connecting portion is a bonding portion.

14. A battery, characterized in that: The battery comprises the battery cell according to any one of claims 1 to 13.

15. An electrical equipment, characterized in that: The electric device comprises the battery as claimed in claim 14.

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