Battery

Abstract

The utility model discloses a battery. The battery comprises a battery cell, the shell comprises a sealing part, a storage part and a cover body part, the sealing part is connected to the storage part and the cover body part, the cover body part and the storage part jointly define a storage cavity, and the battery cell is arranged in the storage cavity; the storage cavity is provided with a plurality of cavity walls, the plurality of cavity walls comprise at least one thinned wall and at least one sunken wall, the sunken wall comprises a sunken area and a non-sunken area, and the maximum thickness of the thinned wall is smaller than the maximum thickness of the non-sunken area. The battery disclosed by the utility model can be used for accommodating more electrolyte and battery cells.

Description

TECHNICAL FIELD

[0001] The utility model relates to battery technology field especially is related to a battery. BACKGROUND

[0002] In the related art, the battery comprises a shell and a battery cell. The shell can be an aluminum plastic film. Before the aluminum plastic film is punched, the aluminum plastic film is flat. After the aluminum plastic film is punched, the battery cell can be placed in the pit of the aluminum plastic film, and then the aluminum plastic film is heat sealed to form a package for the battery cell.

[0003] The volume of the aluminum plastic film punched is usually larger than the volume of the battery cell, which can effectively ensure that the battery cell can be placed in the aluminum plastic film. Further, electrolyte needs to be injected before the aluminum plastic film is packaged. The electrolyte can conduct ions. It can be envisaged that the more electrolyte the aluminum plastic film can accommodate and the larger the volume of the battery cell the aluminum plastic film can accommodate, the better the performance of the battery. However, since the size of the aluminum plastic film is a fixed value, the aluminum plastic film cannot accommodate more electrolyte and battery cells. SUMMARY

[0004] The utility model aims at at least one of the technical problems existing in the prior art. To this end, the utility model provides a battery that can accommodate more electrolyte and battery cells.

[0005] The battery according to the embodiments of the utility model comprises:

[0006] a battery cell;

[0007] a shell comprising a sealing part, a storage part, and a cover part, the sealing part being connected to the storage part and the cover part, the cover part and the storage part together defining a storage cavity, the battery cell being disposed in the storage cavity;

[0008] The cavity wall of the storage cavity has a plurality of cavity walls, the plurality of cavity walls comprising at least one thinned wall and at least one recessed wall, the recessed wall comprising a recessed area and a non-recessed area, and the maximum thickness of the thinned wall being smaller than the maximum thickness of the non-recessed area.

[0009] The battery according to the embodiments of the utility model has at least the following beneficial effects: the shell has a storage cavity, and the battery cell is placed in the storage cavity. Among them, the cavity wall of the storage cavity has a plurality of cavity walls, and the plurality of cavity walls comprises at least one thinned wall and at least one recessed wall. That is, at least a part of the cavity wall of the storage cavity is thinned, and a recess is provided on at least a part of the cavity wall of the storage cavity. After the thinning process, the volume of the storage cavity of the present application is larger than that of the prior art. After the recessed area is provided, the recessed part can accommodate more electrolyte. Therefore, the shell can accommodate more electrolyte and battery cells. Specifically, the battery can accommodate more electrolyte and battery cells.

[0010] According to some embodiments of the battery of the utility model, the cavity wall of the storage cavity comprises a surrounding wall and two first walls arranged oppositely, the two first walls are connected with two ends of the surrounding wall respectively, and the two first walls are arranged on two sides of the battery cell along the thickness direction of the battery cell.

[0011] According to some embodiments of the battery of the utility model, the surrounding wall comprises two second walls arranged oppositely and two third walls arranged oppositely, two ends of the second wall are connected with two third walls respectively, and the second wall and the third wall are connected with the first wall.

[0012] According to some embodiments of the battery of the utility model, the first thinning area comprises a first outer layer, a first metal layer and a first heat sealing layer arranged in sequence, the first un-thinning area comprises a second outer layer, a second metal layer and a second heat sealing layer arranged in sequence, and the thickness of the first heat sealing layer is less than the thickness of the second heat sealing layer.

[0013] According to some embodiments of the battery of the utility model, the first thinning area comprises a first metal layer and a first outer layer arranged in sequence.

[0014] According to some embodiments of the battery of the utility model, the first un-thinning area comprises a second outer layer, a second metal layer and a second heat sealing layer arranged in sequence, and the thickness of the first metal layer is less than the thickness of the second metal layer.

[0015] According to some embodiments of the battery of the utility model, the cavity wall of the storage cavity comprises a surrounding wall and two first walls arranged oppositely, the two first walls are connected with two ends of the surrounding wall respectively, and the two first walls are arranged on two sides of the battery cell along the thickness direction of the battery cell.

[0016] According to the battery of some embodiments of the utility model, the surrounding wall comprises two second walls and two third walls, the two ends of the second wall are connected to the two third walls, and the two second walls and the two third walls are connected to the first wall.

[0017] According to the battery of some embodiments of the utility model, the surrounding wall comprises two second walls and two third walls, the two ends of the second wall are connected to the two third walls, and the two second walls and the two third walls are connected to the first wall.

[0018] According to the battery of some embodiments of the utility model, the depth of the recessed area is L, and 10um≤L≤30um.

[0019] The additional aspects and advantages of the utility model will be partially given in the following description, partially will become obvious from the following description, or be understood by the practice of the utility model. BRIEF DESCRIPTION OF DRAWINGS

[0020] The utility model will be further explained in combination with the drawings and embodiments, wherein:

[0021] Figure 1 It is the schematic diagram of the battery of the first embodiment of the utility model;

[0022] Figure 2 It is the schematic diagram of the battery of the second embodiment of the utility model;

[0023] Figure 3 It is the schematic diagram of the battery of the third embodiment of the utility model;

[0024] Figure 4 It is the schematic diagram of the battery of the fourth embodiment of the utility model;

[0025] Figure 5 It is the schematic diagram of the battery of the fifth embodiment of the utility model;

[0026] Figure 6 It is the schematic diagram of the battery of the sixth embodiment of the utility model;

[0027] Figure 7 It is the schematic diagram of the battery of the seventh embodiment of the utility model;

[0028] Figure 8 It is the schematic diagram of the battery of the eighth embodiment of the utility model.

[0029] Reference signs:

[0030] Battery 10, battery cell 100, shell 200, sealing part 210, storage part 220, cover part 230, storage cavity 240, thinning wall 241, recess wall 242, recess area 243, surrounding wall 244, first thinning area 245, first non-thinning area 246, second wall 247, third wall 248, first wall 249, second thinning area 250, second non-thinning area 260, first outer layer 300, first metal layer 400, first heat sealing layer 500, second outer layer 600, second metal layer 700, second heat sealing layer 800. DETAILED DESCRIPTION

[0031] The embodiments of the present application are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar notations represent the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the drawings are exemplary, only for explaining the present application, and cannot be understood as a limitation of the present application.

[0032] In the description of the present application, it is understood that the orientation description, such as the orientation or position relationship indicated by up, down, front, back, left, right, etc. is based on the orientation or position relationship shown in the drawings, only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as a limitation of the present application.

[0033] In the description of the present application, the meaning of several is more than one, the meaning of multiple is more than two, greater than, less than, more than, etc. are understood as not including the number, above, below, etc. are understood as including the number. If it is described as first, second, only for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features or implicitly indicating the order of indicated technical features.

[0034] In the description of the present application, unless otherwise explicitly limited, the words such as setting, installing, connecting, etc. should be broadly understood, and the skilled in the art can reasonably determine the specific meaning of the above words in the present application according to the specific content of the technical scheme.

[0035] In the description of the present utility model, the description of the reference terms "one embodiment", "some embodiments", "illustrative embodiment", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in combination with the embodiment or example are included in at least one embodiment or example of the present utility model. In the specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0036] The battery can 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., and the present application embodiment is not limited thereto.

[0037] The battery generally includes a cell. The cell includes a positive electrode, a negative electrode, and a separator. During the charging and discharging process of the battery, active ions (such as lithium ions) are embedded and extracted between the positive electrode and the negative electrode. The separator is arranged between the positive electrode and the negative electrode, which can prevent the positive and negative electrodes from short-circuiting, and at the same time, the active ions can pass through.

[0038] In some embodiments, the positive electrode can be a positive electrode sheet, which can include a positive electrode current collector and a positive electrode active material arranged on at least one surface of the positive electrode current collector.

[0039] As an example, the positive electrode current collector has two opposite surfaces in the thickness direction of itself, and the positive electrode active material is arranged on any one or both of the two opposite surfaces of the positive electrode current collector.

[0040] As an example, the positive electrode current collector can adopt a metal foil or a composite current collector. For example, as a metal foil, aluminum with silver plating treatment on the surface, stainless steel with silver plating treatment on the surface, stainless steel, copper, aluminum, nickel, carbon electrode, carbon, nickel, or titanium, etc. can be adopted. The composite current collector can include a high polymer material base layer and a metal layer. The composite current collector can be formed by forming a metal material (aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a high polymer material base material (such as a base material of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0041] As an example, the positive electrode active material can include at least one of a lithium-containing phosphate, a lithium transition metal oxide, and a modified compound of each thereof. However, the present application is not limited to these materials, and other conventional materials that can be used as a battery positive electrode active material can also be used. These positive electrode active materials can be used alone only one or two or more can be used in combination. Among them, examples of the lithium-containing phosphate can include, but are not limited to, at least one of lithium iron phosphate (such as LiFeP04 (which can also be referred to as LFP)), a composite of lithium iron phosphate and carbon, lithium manganese phosphate (such as LiMnP04), a composite of lithium manganese phosphate and carbon, lithium manganese iron phosphate, and a composite of lithium manganese iron phosphate and carbon. Examples of the lithium transition metal oxide can include, but are not limited to, at least one of lithium cobalt oxide (such as LiCo02), lithium nickel oxide (such as LiNi02), lithium manganese oxide (such as LiMn02, LiMn204), lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, lithium nickel cobalt manganese oxide (such as LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 O2 (which can also be referred to as NCM333), LiNi 0.5 Co 0.2 Mn 0.3 O2 (which can also be referred to as NCM523), LiNi 0.5 Co 0.25 Mn 0.25 O2 (which can also be referred to as NCM211), LiNi 0.6 Co 0.2 Mn 0.2 O2 (which can also be referred to as NCM622), LiNi 0.8 Co 0.1 Mn 0.1 O2 (which can also be referred to as NCM811), lithium nickel cobalt aluminum oxide (such as LiNi 0.85 Co 0.15 Al 0.05 O2), and modified compounds thereof.

[0042] In some embodiments, the positive electrode can employ a foam metal. The foam metal can be a foam nickel, a foam copper, a foam aluminum, a foam alloy, or the like. When the foam metal is used as the positive electrode, the surface of the foam metal can not be provided with the positive electrode active material, or of course can be provided with the positive electrode active material. As an example, the foam metal can also be filled or / and deposited with a lithium source material, a potassium metal, or a sodium metal, the lithium source material being a lithium metal and / or a lithium-rich material.

[0043] In some embodiments, the negative electrode can be a negative electrode sheet, and the negative electrode sheet can include a negative electrode current collector.

[0044] As an example, the negative current collector can employ a metal foil, a foam metal, or a composite current collector. For example, as the metal foil, silver surface-treated aluminum or stainless steel, stainless steel, copper, aluminum, nickel, a carbon electrode, nickel, or titanium, etc. can be employed. The foam metal can be a foam nickel, a foam copper, a foam aluminum, a foam alloy, etc. The composite current collector can include a polymer material base layer and a metal layer. The composite current collector can 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 base material (such as a base material of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0045] As an example, the negative electrode sheet can include a negative current collector and a negative active material disposed on at least one surface of the negative current collector.

[0046] As an example, the negative current collector has two surfaces opposite in a thickness direction thereof, and the negative active material is disposed on any one or both of the two opposite surfaces of the negative current collector.

[0047] As an example, the negative active material can employ a negative active material for a battery known in the art. As an example, the negative active material can include at least one of artificial graphite, natural graphite, soft carbon, hard carbon, a silicon-based material, a tin-based material, and lithium titanate, etc. The silicon-based material can be selected from at least one of elemental silicon, a silicon oxide compound, a silicon-carbon composite, a silicon-nitrogen composite, and a silicon alloy. The tin-based material can be selected from at least one of elemental tin, a tin oxide compound, and a tin alloy. However, the present application is not limited to these materials, and other conventional materials that can be used as a negative active material for a battery can also be used. These negative active materials can be used alone or in combination of two or more.

[0048] In some embodiments, the material of the positive current collector can be aluminum, and the material of the negative current collector can be copper.

[0049] In some embodiments, the battery cell further includes a separator disposed between the positive electrode and the negative electrode.

[0050] In some embodiments, the separator is a separator film. The separator film can be of various types, and any known porous structure separator film having good chemical stability and mechanical stability can be used.

[0051] As an example, the material of the separator film can include at least one of glass fiber, non-woven fabric, polyethylene, polypropylene, and polyvinylidene fluoride. The separator film can be a single layer film or a multi-layer composite film. When the separator film is a multi-layer composite film, the materials of the respective layers can be the same or different. The separator can be a separate component located between the positive and negative electrodes, or can be attached to the surface of the positive and negative electrodes.

[0052] In some embodiments, the separator is a solid-state electrolyte. The solid-state electrolyte is disposed between the anode and the cathode, and functions to transport ions and to separate the anode and the cathode.

[0053] In some embodiments, the battery further includes an electrolyte that functions to conduct ions between the anode and the cathode. The electrolyte can be in a liquid state, a gel state, or a solid state. In some embodiments, the liquid electrolyte includes an electrolyte salt and a solvent.

[0054] In some embodiments, the electrolyte salt can include at least one of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium perchlorate, lithium hexafluoroarsenate, lithium bisfluorosulfonylimide, lithium bis-trifluoromethanesulfonylimide, lithium trifluoromethanesulfonate, lithium difluorophosphate, lithium difluoro oxalato borate, lithium bis-oxalato borate, lithium difluoro bis-oxalato phosphate, and lithium tetrafluoro oxalato phosphate.

[0055] In some embodiments, the solvent can include at least one of ethylene carbonate, propylene carbonate, methyl ethyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, butylene carbonate, fluoroethylene carbonate, methyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, methyl butyrate, ethyl butyrate, 1,4-butyrolactone, butyrosulfone, dimethyl sulfone, methyl ethyl sulfone, and diethyl sulfone. The solvent can also be an ether solvent. The ether solvent can include one or more of ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, 1,3-dioxolane, tetrahydrofuran, methyl tetrahydrofuran, diphenyl ether, and a crown ether.

[0056] In some embodiments, the gel-state electrolyte includes a polymer as a backbone network of the electrolyte, in combination with an ionic liquid-lithium salt.

[0057] In some embodiments, the solid-state electrolyte includes a polymer solid-state electrolyte, an inorganic solid-state electrolyte, a composite solid-state electrolyte.

[0058] As an example, the polymer solid-state electrolyte can be a polyether (polyethylene oxide), a polysiloxane, a polycarbonate, a polyacrylonitrile, a polyvinylidene fluoride, a polymethyl methacrylate, a single-ion polymer, a polyionic liquid-lithium salt, a cellulose, or the like.

[0059] As an example, the inorganic solid-state electrolyte can include one or more of an oxide solid-state electrolyte (crystalline perovskite, sodium superionic conductor, garnet, amorphous LiPON thin film), a sulfide solid-state electrolyte (crystalline lithium superionic conductor (lithium germanium phosphorous sulfide, argyrodite), amorphous sulfide), a halide solid-state electrolyte, a nitride solid-state electrolyte, and a hydride solid-state electrolyte.

[0060] As an example, the composite solid-state electrolyte is formed by adding inorganic solid-state electrolyte fillers in a polymer solid-state electrolyte.

[0061] In some embodiments, the battery cell is in a jelly-roll structure. The positive electrode sheet and the negative electrode sheet are wound to form the jelly-roll structure.

[0062] In some embodiments, the battery cell is in a stack structure.

[0063] As an example, a plurality of positive electrode sheets and a plurality of negative electrode sheets can be provided respectively and are alternately stacked.

[0064] As an example, a plurality of positive electrode sheets can be provided, and the negative electrode sheet is folded to form a plurality of folded segments which are stacked.

[0065] As an example, both the positive electrode sheet and the negative electrode sheet are folded to form a plurality of folded segments which are stacked.

[0066] As an example, a plurality of separators can be provided and are respectively arranged between any adjacent positive electrode sheets or negative electrode sheets.

[0067] As an example, the separators can be continuously provided and are arranged between any adjacent positive electrode sheets or negative electrode sheets by folding or winding.

[0068] In some embodiments, the battery cell can have a cylindrical shape, a flat shape, or a polygonal shape.

[0069] In some embodiments, the battery cell can be provided with tabs. The tabs can conduct current out of the battery cell. The tabs include positive tabs and negative tabs.

[0070] In some embodiments, the battery can include a housing. The housing is used to encapsulate the battery cell and other components such as electrolyte. The housing can be a steel shell, an aluminum shell, a plastic shell (such as polypropylene), a composite metal shell (such as a copper-aluminum composite shell), or an aluminum-plastic film, etc.

[0071] As an example, the battery can be a cylindrical battery, a prismatic battery, a pouch battery, or a battery of other shapes. The prismatic battery includes, but is not limited to, a square battery, a blade battery, and a polygonal battery such as a hexagonal battery, etc.

[0072] The battery referred to in the embodiments of the present application refers to a single physical module including one or more batteries to provide higher voltage and capacity.

[0073] In some embodiments, the battery can be a battery module. When there are multiple batteries, the multiple batteries are arranged and fixed to form a battery module.

[0074] In some embodiments, the battery can be a battery pack. The battery pack includes a box and a battery. The battery or the battery module is contained in the box.

[0075] In some embodiments, the box can be part of a chassis structure of a vehicle. For example, portions of the box can become at least part of a floor of the vehicle, or portions of the box can become at least part of cross members and longitudinal members of the vehicle.

[0076] Embodiments of the present application provide a power consuming device using a battery as a power source. The power consuming device can be, but is not limited to, a mobile phone, a tablet, a notebook computer, an electric toy, an electric tool, an electric vehicle, an electric car, a ship, a spacecraft, etc. The electric toy can include a stationary or mobile electric toy, such as a game console, an electric car toy, an electric ship toy, an electric plane toy, etc. The spacecraft can include an airplane, a rocket, a space shuttle, a spacecraft, etc.

[0077] In the related art, a battery includes a shell and a battery cell. The shell can be an aluminum plastic film. Before being punched, the aluminum plastic film is planar. After being punched, the battery cell can be placed in the pit of the aluminum plastic film, and then the aluminum plastic film is heat sealed to form a package for the battery cell.

[0078] The volume of the aluminum plastic film punched is usually larger than the volume of the battery cell, which can effectively ensure that the battery cell can be placed in the aluminum plastic film. Further, before the aluminum plastic film is packaged, electrolyte needs to be injected. The electrolyte can conduct ions. It can be thought that the more electrolyte the aluminum plastic film can accommodate, and the larger the volume of the battery cell the aluminum plastic film can accommodate, the better the performance of the battery. However, since the size of the aluminum plastic film is a fixed value, the aluminum plastic film cannot accommodate more electrolyte and battery cells. Therefore, the present application provides a battery.

[0079] Please refer to Figures 1 to 8In some embodiments, the battery 10 comprises: an electric core 100 and a shell 200. The electric core 100 comprises a positive electrode sheet and a negative electrode sheet. The electric core 100 can be formed by laminating the positive electrode sheet and the negative electrode sheet. The electric core 100 can also be formed by laminating the positive electrode sheet and the negative electrode sheet and then winding them. The shell 200 comprises a sealing part 210, a storage part 220 and a cover part 230. The shell 200 can be an aluminum plastic film. The sealing part 210 is connected to the storage part 220 and the cover part 230. The cover part 230 and the storage part 220 jointly define a storage cavity 240. The sealing part 210 is used to encapsulate the storage cavity 240. The electric core 100 is arranged in the storage cavity 240. The cavity wall of the storage cavity 240 has a plurality of walls. The shape of the storage cavity 240 is not limited. For example, the shape of the storage cavity 240 can be a cylinder, a cuboid, a square, and other polygonal bodies, etc. The number of cavity walls of the storage cavity 240 with different shapes is different. The plurality of cavity walls can be six, eight or more. The plurality of cavity walls comprises at least one thinned wall 241, at least one normal wall and at least one recessed wall 242. Alternatively, the plurality of cavity walls comprises at least one thinned wall 241 and at least one recessed wall 242. That is, the cavity wall of the storage cavity 240 can be partially thinned and recessed, or all the cavity walls of the storage cavity 240 can be thinned and recessed. The recessed wall 242 specifically refers to the recessed wall 242 comprising a recessed area 243 and a non-recessed area. The recessed area 243 specifically refers to a blind hole or a groove on the recessed wall 242. That is, there are recessed positions on the surface of the recessed wall 242. These positions can be used to store more electrolyte. The non-recessed area refers to the area on the recessed wall 242 without recess. The shape of the groove is not limited, such as linear or point-shaped. The shape of the blind hole is also not limited, such as a round hole or a square hole. In addition, the number of recessed areas 243 is not limited, such as two, three or five recessed areas 243 on the recessed wall 242. The plurality of recessed areas 243 can be linear or arrayed. The maximum thickness of the thinned wall 241 is less than the maximum thickness of the recessed wall 242. The maximum thickness of the recessed wall 242 refers to the maximum thickness of the non-recessed area. The maximum thickness of the thinned wall 241 is less than the maximum thickness of the recessed wall 242 specifically refers to the thickness of the thinned wall 241 being thinned, so that the thickness of the thinned wall 241 is less than the thickness of the normal wall and also less than the maximum thickness of the recessed wall 242. The thinned wall 241 can be thinned by laser or hot pressing.

[0080] Specifically, the shell 200 has a storage cavity 240, and the battery cell 100 is placed in the storage cavity 240, wherein the cavity wall of the storage cavity 240 has a plurality of cavity walls, and the plurality of cavity walls include at least one thinned wall 241 and at least one recessed wall 242, that is, at least a part of the cavity wall of the storage cavity 240 is thinned, and the recessed area 243 is arranged on at least a part of the cavity wall of the storage cavity 240. After the thinning treatment, the volume of the storage cavity 240 of the present application is larger than that of the prior art, and after the recessed area 243 is arranged, the recessed part can accommodate more electrolyte. Therefore, the shell 200 can accommodate more electrolyte and battery cells 100, wherein the more electrolyte the shell 200 can accommodate, the better the wettability of the battery cell 100, the more battery cells 100 the shell 200 can accommodate, and the higher the energy density of the battery. Specifically, the battery 10 can accommodate more electrolyte and battery cells 100. The performance of the battery 10 is better.

[0081] Further, the specific structure of the cavity wall of the storage cavity 240 is introduced below. Please refer to Figure 3 、 Figure 4 、 Figure 6 and Figure 8 In some embodiments, the cavity wall of the storage cavity 240 includes a surrounding wall 244 and two oppositely arranged first walls 249. The surrounding wall 244 can surround a through hole, and the openings at both ends of the through hole are closed by the first walls 249, that is, the two first walls 249 are respectively connected to the two ends of the surrounding wall 244. The two first walls 249 are respectively arranged on both sides of the battery cell 100 along the thickness direction of the battery cell 100. In this embodiment, the surrounding wall 244 can be partially thinned, and the surrounding wall 244 is the thinned wall 241, and the first wall 249 is the recessed wall 242. That is, the surrounding wall 244 includes a first thinned area 245 and a first non-thinned area 246. The first wall 249 is provided with a recessed area 243, the maximum thickness of the first thinned area 245 is H1, the maximum thickness of the first non-thinned area 246 is H2, the maximum thickness of the first wall 249 is H3, and H1

[0082] Further, some specific embodiments of the surrounding wall 244 are introduced below. Please refer to Figure 3 、 Figure 4 、 Figure 6 and Figure 8In some embodiments, the surrounding wall 244 comprises two second walls 247 arranged oppositely and two third walls 248 arranged oppositely. The two ends of the second walls 247 are connected to the two third walls 248 respectively, and the two second walls 247 and the two third walls 248 surround the first wall 249. In the above manner, the surrounding wall 244 has the first thinned area 245 and the first non-thinned area 246. The second walls 247 can be arranged as the first thinned area 245, and the third walls 248 can be arranged as the first non-thinned area 246. Alternatively, the third walls 248 can be arranged as the first thinned area 245, and the second walls 247 can be arranged as the first non-thinned area 246. Specifically, the second walls 247 can be thinned, and the third walls 248 can also be thinned. More specifically, one of the second walls 247 can be thinned, or both of the second walls 247 can be thinned. One of the third walls 248 can be thinned, or both of the third walls 248 can be thinned.

[0083] Further, please refer to Figure 3 、 Figure 4 and Figure 6 In some embodiments, the first thinned area 245 comprises a first outer layer 300, a first metal layer 400 and a first heat-seal layer 500 arranged in sequence. The first outer layer 300 can be a nylon layer, the first metal layer 400 can be an aluminum layer, and the first heat-seal layer 500 can be a PP layer or a PE layer. The first non-thinned area 246 comprises a second outer layer 600, a second metal layer 700 and a second heat-seal layer 800 arranged in sequence. The second outer layer 600 can be a nylon layer, the second metal layer 700 can be an aluminum layer, and the second heat-seal layer 800 can be a PP layer or a PE layer. The thickness of the first heat-seal layer 500 is less than the thickness of the second heat-seal layer 800. That is, the thickness of the first thinned area 245 is less than the thickness of the first non-thinned area 246, which is achieved by thinning the first heat-seal layer 500. Figure 3 and Figure 4 illustrates that the first heat-seal layer 500 is completely removed, Figure 6 illustrates that the first heat-seal layer 500 is partially thinned.

[0084] Further, the above-mentioned way of thinning part of the first heat-seal layer 500 can improve the energy density of the battery 10. In some cases, the entire first heat-seal layer 500 can also be thinned. That is, please refer to Figure 3 and Figure 4 In some embodiments, the first thinned area 245 comprises a first metal layer 400 and a first outer layer 300 arranged in sequence. Specifically, the cavity wall of the storage cavity 240 only has the first metal layer 400 and the first outer layer 300 arranged in sequence. After the first heat-seal layer 500 is discarded, the volume of the storage cavity 240 can be greatly improved, thereby improving the energy density of the battery 10.

[0085] Further, after the first thermal sealing layer 500 is completely removed, the first metal layer 400 can be thinned, thereby further improving the energy density of the battery 10. Specifically, please refer to Figure 6 In some embodiments, the first un-thinned region 246 includes a second outer layer 600, a second metal layer 700 and a second thermal sealing layer 800 which are sequentially stacked, and the thickness of the first metal layer 400 is less than the thickness of the second metal layer 700. The thickness of the first metal layer 400 can be one fourth, one half or three fourths of the thickness of the second metal layer 700.

[0086] Further, the following describes another specific embodiment of the surrounding wall 244. Please refer to Figure 4 Figure 8 Figure 8 and Figure 1 In some embodiments, the cavity wall of the storage cavity 240 includes the surrounding wall 244 and two first walls 249 which are oppositely arranged and connected to the two ends of the surrounding wall 244 respectively. The two first walls 249 are arranged on the two sides of the battery cell 100 along the thickness direction of the battery cell 100. The first wall 249 is provided with a second thinned region 250, and the surrounding wall 244 is provided with a recessed region 243. The maximum thickness of the second thinned region 250 is H4, and the maximum thickness of the surrounding wall 244 is H5, H4 < H5. That is, only the recessed region 243 is arranged on the surrounding wall 244, and only grooves or blind holes are arranged on the surrounding wall 244, thereby accommodating more electrolyte. After the first wall 249 is thinned, the volume of the battery cell 100 in the thickness direction can be increased, thereby effectively improving the energy density of the battery 10. In addition, the first wall 249 can be provided with a second un-thinned region 260. For example, one of the two first walls 249 is provided with the second thinned region 250, and the other first wall 249 is provided with the second un-thinned region 260. The second thinned region 250 can include a first outer layer 300, a first metal layer 400 and a first thermal sealing layer 500 which are sequentially stacked. The first outer layer 300 can be a nylon layer, the first metal layer 400 can be an aluminum layer, and the first thermal sealing layer 500 can be a PP layer or a PE layer. The second un-thinned region 260 can include a second outer layer 600, a second metal layer 700 and a second thermal sealing layer 800 which are sequentially stacked. Alternatively, the second thinned region 250 can include a first outer layer 300 and a first metal layer 400 which are sequentially stacked. Figure 2 and Figure 5 illustrates that the first thermal sealing layer 500 is completely removed, Figure 7 illustrates that the first thermal sealing layer 500 is partially thinned, Figure 1 illustrates that the first metal layer is partially thinned.

[0087] Further, please refer to Figure 2 ​​In some embodiments, the surrounding wall 244 comprises two second walls 247 arranged oppositely and two third walls 248 arranged oppositely, two ends of the second wall 247 are connected to the two third walls 248 respectively, and the two second walls 247 and the two third walls 248 are connected to the first wall 249. The second wall 247 is provided with the recessed area 243. Specifically, in the embodiment, the recessed area 243 is arranged on the second wall 247, and the third wall 248 is not provided with the recessed area 243. By arranging the recessed area 243 on the second wall 247 and not arranging the recessed area 243 on the third wall 248, the storage cavity 240 can contain more electrolyte, and the third wall 248 does not need to be processed, thereby reducing the manufacturing cost.

[0088] Further, please refer to Figure 5 Figure 7 Figure 1 Figure 2 In some embodiments, the surrounding wall 244 comprises two second walls 247 arranged oppositely and two third walls 248 arranged oppositely, two ends of the second wall 247 are connected to the two third walls 248 respectively, and the two second walls 247 and the two third walls 248 are connected to the first wall 249. The third wall 248 is provided with the recessed area 243. Specifically, in the embodiment, the recessed area 243 is arranged on the third wall 248, and the second wall 247 is not provided with the recessed area 243. By arranging the recessed area 243 on the third wall 248 and not arranging the recessed area 243 on the second wall 247, the storage cavity 240 can contain more electrolyte, and the second wall 247 does not need to be processed, thereby reducing the manufacturing cost.

[0089] Further, in some embodiments, the depth of the recessed area 243 is L, and 10um≤L≤30um. Specifically, the depth of the recessed area 243 can be 10um, 15um, 20um or 30um. When the depth of the recessed area 243 is less than 10um, the depth of the recessed area 243 is too small, which can result in that the storage cavity 240 contains less electrolyte. When the depth of the recessed area 243 is greater than 30um, the depth of the recessed area 243 is too large, which can result in that the shell 200 is easy to be broken, and the safety of the battery 10 is reduced. In some cases, in addition to arranging the recessed area 243 on the cavity wall of the storage cavity 240, the recessed area 243 can also be arranged on the pole piece of the battery cell 100, such as arranging a groove or a blind hole on the pole piece.

[0090] The embodiments of the utility model are described in detail above combined with the drawings, but the utility model is not limited to the above-mentioned embodiments, and within the knowledge range possessed by the ordinary skilled in the art, various changes can be made without departing from the purpose of the utility model. In addition, the embodiments of the utility model and the features in the embodiments can be combined with each other without conflict.

Claims

1. A battery, characterized by, The application relates to a battery cell and a shell thereof. The shell comprises a sealing part, a storage part and a cover part, the sealing part is connected to the storage part and the cover part, the cover part and the storage part jointly define a storage cavity, and the battery cell is arranged in the storage cavity. The cavity wall of the storage cavity comprises a surrounding wall and two first walls arranged oppositely, the two first walls are connected to two ends of the surrounding wall respectively, and the two first walls are arranged on two sides of the battery cell along the thickness direction of the battery cell. The surrounding wall comprises a first thinned area and a first non-thinned area, the first wall is provided with the recessed area, the maximum thickness of the first thinned area is H1, the maximum thickness of the first non-thinned area is H2, and the maximum thickness of the first wall is H3, H1 < H2 = H3.

2. The battery of claim 1, wherein, The surrounding wall comprises two second walls arranged oppositely and two third walls arranged oppositely, the two ends of the second wall are connected to the two third walls respectively, the two second walls and the two third walls are connected to the first wall, the second wall is arranged as the first thinned area, and the third wall is arranged as the first non-thinned area.

3. The battery of claim 2, wherein, The first thinned area comprises a first outer layer, a first metal layer and a first heat-sealing layer arranged in sequence, the first non-thinned area comprises a second outer layer, a second metal layer and a second heat-sealing layer arranged in sequence, and the thickness of the first heat-sealing layer is smaller than that of the second heat-sealing layer.

4. The battery of claim 2, wherein, The first thinned area comprises a first metal layer and a first outer layer arranged in sequence.

5. The battery of claim 2, wherein, The first non-thinned area comprises a second outer layer, a second metal layer and a second heat-sealing layer arranged in sequence, and the thickness of the first metal layer is smaller than that of the second metal layer.

6. The battery of claim 5, wherein, The cavity wall of the storage cavity comprises a surrounding wall and two first walls arranged oppositely, the two first walls are connected to two ends of the surrounding wall respectively, and the two first walls are arranged on two sides of the battery cell along the thickness direction of the battery cell.

7. The battery of claim 1, wherein, The surrounding wall comprises two second walls arranged oppositely and two third walls arranged oppositely, the two ends of the second wall are connected to the two third walls respectively, the two second walls and the two third walls are connected to the first wall, and the second wall is provided with the recessed area.

8. The battery of claim 7, wherein, The surrounding wall comprises two second walls arranged oppositely and two third walls arranged oppositely, the two ends of the second wall are connected to the two third walls respectively, the two second walls and the two third walls are connected to the first wall, and the third wall is provided with the recessed area.

9. The battery of claim 7, wherein, The depth of the recessed area is L, and 10 um <= L <= 30 um.

10. The battery of claim 1, wherein, ​

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