Battery cell and manufacturing method therefor, battery, electric device and energy storage device

Abstract

A battery cell (1) and a manufacturing method therefor, a battery (100), an electric device and an energy storage device. The battery cell (1) comprises: a casing (10) having a plurality of casing walls enclosing an accommodating space, wherein at least one electrode assembly (30) is accommodated in the accommodating space, the electrode assembly (30) comprises a tab (32), and the plurality of casing walls comprise a first casing wall (12); an electrode terminal (22) passing through the first casing wall (12) and having a first connection portion (221) located in the accommodating space, wherein the first connection portion (221) has a connection face (221a) close to one side of the electrode assembly (30) in the direction of the thickness of the first casing wall (12), and the connection face (221a) is connected to the tab (32); and an insulating member (23) comprising a positioning portion (231), wherein the positioning portion (231) is arranged around the outer periphery of the first connection portion (221), the positioning portion (231) has a first face (231a) close to one side of the electrode assembly (30) in the direction of the thickness of the first casing wall (12), and the first face (231a) is flush with at least the part of the connection face (221a) close to the positioning portion (231).

Description

Battery cell and manufacturing method thereof, battery, electric device and energy storage device

[0001] Cross-reference to Related Applications

[0002] The present disclosure is based on and claims priority to Chinese Patent Application No. 202410842371.8, filed on June 26, 2024, entitled “Battery cell and manufacturing method thereof, battery, electric device and energy storage device”, the entire contents of which are incorporated herein by reference. TECHNICAL FIELD

[0003] The present disclosure relates to the technical field of batteries, and in particular to a battery cell, a battery, an electric device, an energy storage device, and a battery cell manufacturing method. BACKGROUND

[0004] New energy batteries are increasingly widely used in life and industry. New energy batteries are not only applied to energy storage power supply systems such as hydroelectric, thermal, wind, and solar power stations, but are also widely used in electric bicycles, electric motorcycles, electric vehicles, and other electric vehicles, as well as aerospace and other fields. With the continuous expansion of the application field of power batteries, not only are higher requirements placed on the performance and reliability of the batteries, but the demand for lightweight batteries is also increasing.

[0005] SUMMARY

[0006] To solve the above technical problems, the present disclosure provides a battery cell, a battery, an electric device, an energy storage device, and a battery cell manufacturing method with high reliability and lightweight.

[0007] The present disclosure is achieved by the following technical solutions.

[0008] The first aspect of the present disclosure provides a battery cell, comprising a shell, the shell specifically comprising a plurality of shell walls enclosing a containing space, the containing space accommodating at least one electrode assembly, the electrode assembly comprising a tab, and the plurality of shell walls comprising a first shell wall; an electrode terminal penetrating through the first shell wall and having a first connecting portion located in the containing space, the first connecting portion having a connecting surface on the side close to the electrode assembly along the thickness direction of the first shell wall, the connecting surface being connected with the tab; and an insulating member comprising a positioning portion, the positioning portion being arranged around the outer periphery of the first connecting portion, the positioning portion having a first surface on the side close to the electrode assembly along the thickness direction of the first shell wall, and the first surface being flush with at least the part of the connecting surface close to the positioning portion.

[0009] The first surface is used to support the pressing piece in the tab and electrode terminal connecting process, and the pressing piece is used to press the tab against the connecting surface, so that the gap between the tab and the electrode terminal is reduced, and the connection between the tab and the electrode terminal is more reliable, thereby improving the connection reliability. In addition, the electrode terminal does not need to be increased in size, which not only does not increase the weight of the battery too much, but also does not increase the cost too much, thereby facilitating the lightweight and cost control of the battery monomer and even the battery. If the volume of the electrode terminal is increased to provide a support space for the pressing piece, the weight of the battery monomer will be greatly increased, which is not conducive to the lightweight of the battery monomer, and the cost is high.

[0010] In some embodiments, the entire connecting surface is flush with the first surface.

[0011] The entire connecting surface is flush with the first surface, which facilitates the pressing of the tab by the pressing piece and helps to increase the connection area between the tab and the electrode terminal, thereby improving the overcurrent capacity.

[0012] In some embodiments, the tab is directly connected to the connecting surface.

[0013] The tab is directly connected to the connecting surface, which can shorten the overcurrent path and reduce the impedance during the charging and discharging process of the battery monomer. In addition, the adapter piece can be omitted, so that the battery monomer and even the battery are more lightweight.

[0014] In some embodiments, along the thickness direction of the tab, the tab and the connecting surface have overlapping parts, and the tab and the first surface have overlapping parts.

[0015] The tab and the first surface have overlapping parts, which can increase the pressing area of the pressing piece pressing the tab, so that the tab is more fitted to the connecting surface of the electrode terminal, and helps to improve the connection reliability of the tab and the electrode terminal.

[0016] In some embodiments, along the thickness direction of the tab, the first surface abuts against the tab.

[0017] The first surface abuts against the tab, which supports the tab through the first surface and the connecting surface, reduces the risk of deformation of the tab, and helps to improve the connection reliability of the tab and the electrode terminal.

[0018] In some embodiments, the positioning part has a second surface, and the second surface is arranged around the outer periphery of the first connecting part and in contact with the outer peripheral surface of the first connecting part.

[0019] In some embodiments, the height difference between the connecting surface and the first surface along the thickness direction of the first shell is within the range of 0mm to 0.3mm.

[0020] By increasing the height of the positioning part, the first surface of the positioning part is substantially flush with the connecting surface, and the height difference error (for example, machining error) is controlled within a suitable range, which can make the tab more closely pressed on the connecting surface, and helps to improve the connection reliability.

[0021] In some embodiments, the first surface has a size along the length direction and / or the width direction of the first shell wall of greater than or equal to 1 mm and less than or equal to 3 mm.

[0022] The first surface has a suitable size, so that the first surface has enough supporting space to support the pressing piece, thereby enabling the pressing piece to press the tab more closely on the connecting surface, which helps to improve the connection reliability.

[0023] In some embodiments, the tab is welded to the connecting surface.

[0024] In the tab and electrode terminal connection process, since the pressing piece can press the tab more closely on the connecting surface of the electrode terminal, the risk of false welding can be reduced, and the connection efficiency and reliability can be improved.

[0025] In some embodiments, the electrode terminal includes a terminal plate and a terminal disc connected to each other, the first connecting part includes the terminal disc, and the terminal disc includes the connecting surface.

[0026] The terminal disc includes the connecting surface, which is substantially planar, so that the connecting surface is more closely fitted with the tab, facilitating subsequent connection and improving connection reliability.

[0027] In some embodiments, the positioning part has a second surface that is arranged around the outer periphery of the first connecting part and in contact with the outer peripheral surface of the first connecting part.

[0028] Since the positioning part is flush with the first connecting part along the thickness direction of the first shell wall, the positioning part can more stably surround the first connecting part, improving the positioning stability and reducing the risk of shaking during the connection (such as welding) of the tab and the first connecting part, which is beneficial to the connection reliability.

[0029] In some embodiments, the insulating piece further includes a portion located between the first connecting part and the first shell wall along the thickness direction of the first shell wall.

[0030] The portion located between the first connecting part and the first shell wall is used to isolate the first connecting part from the first shell wall, reducing the risk of short circuit, and also improving the positioning stability of the first connecting part.

[0031] In some embodiments, the electrode terminal further includes a second connecting part located outside the shell along the thickness direction of the first shell wall, and the second connecting part is connected to the first connecting part.

[0032] The second connecting part is used for connecting with an external bus component, connecting more batteries, improving the capacity of the batteries, and meeting the demand of high-power electricity consumption.

[0033] In some embodiments, the second connecting part includes a terminal plate.

[0034] The second connecting part includes a terminal plate, so that the connecting surface is more closely attached to the bus component, facilitating subsequent connection and improving connection reliability.

[0035] In some embodiments, the insulating piece further includes a protruding part protruding towards the side of the electrode assembly along the thickness direction of the first shell wall.

[0036] The protruding part can be used to abut against the main body part of the electrode assembly, reducing the risk of electrode assembly shaking.

[0037] The second aspect of the present disclosure provides a battery, which includes a box body and a battery cell provided by the first aspect described above, arranged in the box body.

[0038] The third aspect of the present disclosure provides a power consumption device, which includes a battery cell provided by the first aspect described above or a battery provided by the second aspect described above, and the battery can provide electric energy for the power consumption device.

[0039] The fourth aspect of the present disclosure provides an energy storage device, which includes a battery cell provided by the first aspect described above or a battery provided by the second aspect described above, and the battery can store and provide electric energy.

[0040] The fifth aspect of the present disclosure provides a battery manufacturing method, the battery includes an electrode assembly, a first shell wall, an electrode terminal mounted on the first shell wall, and an insulating piece, the electrode assembly includes a tab, the battery manufacturing method includes: a tab positioning step, in which a pressing piece is used to press the tab against a first connecting part of the electrode terminal, the first connecting part has a connecting surface, the electrode terminal is located in a positioning part of the insulating piece, the positioning part surrounds the outer periphery of the first connecting part, the positioning part has a first surface, the first surface is flush with at least a part of the connecting surface, and the pressing piece is at least partially supported on the first surface; and a tab connecting step, in which the tab pressed against the connecting surface is connected with the connecting surface.

[0041] The pressing piece is supported by the first surface, and the pressing piece is used to press the tab against the electrode terminal, thereby reducing the gap between the tab and the electrode terminal, and further making the connection more reliable, while not only not increasing the weight of the battery too much, but also not increasing the cost too much. If the support space for the pressing piece is provided by increasing the volume of the electrode terminal, the weight of the battery will be greatly increased, which is not conducive to the lightweight of the battery, and the cost is high.

[0042] In some embodiments, before the tab positioning step, the battery manufacturing method further comprises an electrode terminal positioning step of positioning the electrode terminal in the positioning portion so that the positioning portion surrounds the first connecting portion.

[0043] The electrode terminal is positioned in the positioning portion so that the positioning portion more stably encloses the first connecting portion therein, improving positioning stability, reducing the risk of tab shaking during connection (such as welding) with the first connecting portion, and facilitating connection reliability.

[0044] In some embodiments, in the tab connecting step, the tab is welded to the connecting surface while the pressing member is kept pressing the tab, and the pressing member surrounds the welding area of the tab and the connecting surface.

[0045] The tab and the connecting surface are welded while the pressing member is kept pressing the tab, so that the tab and the connecting surface are always in close contact during welding, and the welding is more reliable.

[0046] In some embodiments, before the tab positioning step, the battery cell manufacturing method further comprises a tab pre-welding step of pre-welding a plurality of tab pieces of the tab into one body by ultrasonic welding to form a first welding mark; and the tab connecting step comprises directly laser welding the tab pressed on the connecting surface to the connecting surface to form a second welding mark, the second welding mark at least partially overlapping the first welding mark.

[0047] By first ultrasonic welding a plurality of tab pieces of the tab into one body, and then connecting the tab to the electrode terminal by laser welding based on the ultrasonic welding, the risk of false welding is reduced, and the connection reliability is improved.

[0048] In some embodiments, the connecting surface has a dimension D1 along the length direction of the first shell wall, the first surface has a dimension D2 along the length direction of the first shell wall, the pressing member has a dimension D3 along the length direction of the first shell wall, the pressing member has a dimension W1 along the width direction of the first shell wall, the first surface has a dimension W2 along the width direction of the first shell wall, and the pressing member has a dimension W3 along the width direction of the first shell wall, wherein D1+2D2≥D3 and W1+2W2≥W3.

[0049] Because D1+2D2≥D3 and W1+2W2≥W3, at least part of the pressing member is supported by the first surface of the positioning portion, so that the tab can be more closely pressed against the connecting surface of the first connecting portion, and the connection reliability is improved.

[0050] Inventive effects:

[0051] Through the present disclosure, the reliability of the battery can be improved, and the lightweight and cost control of the battery are facilitated. BRIEF DESCRIPTION OF DRAWINGS

[0052] Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments with reference made to the accompanying drawings. The drawings are for purposes of illustration only and are not intended to limit the present disclosure. The same reference numerals in different drawings identify the same components throughout the different drawings. In the drawings:

[0053] FIG. 1 is a structural schematic diagram of a vehicle according to some embodiments of the present disclosure;

[0054] FIG. 2 is a perspective exploded schematic diagram of a battery according to some embodiments of the present disclosure;

[0055] FIG. 3 is a perspective exploded schematic diagram of a battery cell according to some embodiments of the present disclosure;

[0056] FIG. 4 is a structural schematic diagram of an electrode assembly and an end cover connected together according to some embodiments of the present disclosure;

[0057] FIG. 5 is an exploded schematic diagram of an electrode assembly and an end cover according to some embodiments of the present disclosure;

[0058] FIG. 6 is an enlarged schematic diagram of a partial structure of the electrode assembly in FIG. 5;

[0059] FIG. 7 is an enlarged schematic diagram of a partial structure of an electrode assembly according to some other embodiments of the present disclosure;

[0060] FIG. 8 is a structural schematic diagram of an end cover according to some embodiments of the present disclosure;

[0061] FIG. 9 is a top view of an end cover according to some embodiments of the present disclosure;

[0062] FIG. 10 is an enlarged schematic diagram of a partial cross-sectional view of an end cover according to some embodiments of the present disclosure;

[0063] FIG. 11 is a cross-sectional schematic diagram of a welding presser pressing a tab on an electrode terminal according to some embodiments of the present disclosure;

[0064] FIG. 12 is a flowchart of a battery manufacturing method according to some embodiments of the present disclosure;

[0065] FIG. 13 is a flowchart of a battery manufacturing method according to some other embodiments of the present disclosure.

[0066] Reference numeral explanation

[0067] 1000 - vehicle;

[0068] 100 - battery; 200 - controller; 300 - motor;

[0069] 1 - battery;

[0070] 2 - case; 3 - lower case; 4 - upper case;

[0071] 10 - housing; 11 - case; 12 - first housing wall;

[0072] 22 - electrode terminal; 22a - positive electrode terminal; 22b - negative electrode terminal; 221 - first connecting portion; 221a - connecting surface; 222 - second connecting portion; 231 - positioning portion; 231a - first surface; 231b - second surface; 2211 - terminal disc; 2221 - terminal plate; 23 - insulating member; 233 - protruding portion; 234 - anti-explosion valve avoiding hole; 235 - liquid injection avoiding hole;

[0073] 30 - electrode assembly; 31 - main body portion; 32 - tab; 32a - tab piece; 32c - positive electrode tab; 32d - negative electrode tab; 321 - connecting portion; 322 - gathering portion; 322b - second welding connecting portion; 322c - first welding connecting portion;

[0074] O - center; X - layer thickness direction; Y - thickness direction; Z - length direction; S - pressing member. DETAILED DESCRIPTION

[0075] The embodiments of the technical solutions of the present disclosure will be described in detail below with reference to the drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present disclosure, and therefore only serve as examples, and cannot limit the protection scope of the present disclosure.

[0076] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present disclosure; the terms "include" and "have" and any variations thereof in the specification and the above description of drawings are intended to cover not exclusive inclusion.

[0077] In the description of the embodiments of the present disclosure, the technical terms "first", "second", "third" and the like are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present disclosure, the meaning of "a plurality of" is two or more, unless otherwise explicitly and specifically limited.

[0078] Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the present disclosure. The appearance of the phrase in various places in the specification does not necessarily all refer to the same embodiment, nor is it necessarily independent or alternative embodiments to other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0079] In the description of the embodiments of the present disclosure, the term "and / or" is merely an association relationship of associated objects, and can represent three relationships, for example, A and / or B, which can represent three cases of A existing alone, A and B existing together, and B existing alone. In addition, the character " / " herein generally represents an "or" relationship between the front and rear associated objects.

[0080] In the description of the embodiments of the present disclosure, the orientations or positional relationships indicated by the technical terms "length", "width", "thickness", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "circumferential", and the like are based on the orientations or positional relationships shown in the drawings, and are merely for the convenience of describing the embodiments of the present disclosure and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed, operated or used in a particular orientation, and therefore cannot be understood as a limitation on the embodiments of the present disclosure.

[0081] In the description of the embodiments of the present disclosure, unless otherwise explicitly specified and limited, the technical terms "mounting", "connection", "connection", "fixing", and the like should be understood in a broad sense, for example, can be fixed connection, can also be detachable connection, or can be integrated; can be mechanical connection, can also be electrical connection; can be directly connected, can also be indirectly connected through an intermediate medium, can be the communication inside two elements or the interaction relationship between two elements. For those skilled in the art, the specific meanings of the above terms in the embodiments of the present disclosure can be understood according to the specific circumstances.

[0082] In the description of the embodiments of the present disclosure, unless otherwise explicitly specified and limited, the technical term "contact" should be understood in a broad sense, which can be direct contact or contact through an intermediate medium layer, and can be contact between two objects in contact without interaction force, or contact between two objects in contact with interaction force.

[0083] In the embodiments of the present disclosure, the battery cell can be a secondary battery, which refers to a battery that can continue to be used by activating the active material through charging after the battery cell is discharged.

[0084] The battery cell 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 embodiments of the present disclosure are not limited thereto.

[0085] The battery cell generally includes an electrode assembly. The electrode assembly 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 inserted 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.

[0086] 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 disposed on at least one surface of the positive electrode current collector.

[0087] As an example, the positive electrode current collector has two surfaces opposite in the thickness direction thereof, and the positive electrode active material is disposed on either one or both of the two opposite surfaces of the positive electrode current collector.

[0088] As an example, the positive electrode current collector can employ a metal foil or a composite current collector. For example, as a metal foil, silver surface-treated aluminum or stainless steel, stainless steel, copper, aluminum, nickel, a carbon electrode, carbon, nickel, or titanium, etc. can be employed. 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 (aluminum, aluminum 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.).

[0089] As an example, the positive electrode active material can include at least one of lithium-containing phosphates, lithium transition metal oxides, and respective modified compounds thereof. However, the disclosure is not limited to these materials, and other conventional materials that can be used as battery positive electrode active materials 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 lithium-containing phosphates can include, but are not limited to, at least one of lithium iron phosphate (such as LiFePO4 (which can also be referred to as LFP)), a composite material of lithium iron phosphate and carbon, lithium manganese phosphate (such as LiMnPO4), a composite material of lithium manganese phosphate and carbon, lithium manganese iron phosphate, and a composite material of lithium manganese iron phosphate and carbon.

[0090] In some embodiments, the positive electrode can employ a foamed metal. The foamed metal can be foamed nickel, foamed copper, foamed aluminum, foamed alloy, or foamed carbon, etc. When the foamed metal is used as a positive electrode, the surface of the foamed metal can not be provided with a positive electrode active material, or of course, a positive electrode active material can be provided. As an example, the foamed 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.

[0091] In some embodiments, the negative electrode can be a negative electrode sheet, which can include a negative electrode current collector.

[0092] As an example, the negative current collector can employ a metal foil, a foam metal, or a composite current collector. For example, as a metal foil, silver surface-treated aluminum or stainless steel, stainless steel, copper, aluminum, nickel, a carbon electrode, or the like can be employed. The composite current collector can include a polymer material base layer and a metal layer. The foam metal can be a foam nickel, a foam copper, a foam aluminum, a foam alloy, or a foam carbon, or the like. The composite current collector can be formed by forming a metal material (copper, a copper alloy, nickel, a nickel alloy, titanium, a titanium alloy, silver, and a silver alloy, or the like) on a polymer material base material (a base material of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, or the like). In some embodiments, the material of the positive current collector can be aluminum, and the material of the negative current collector can be copper.

[0093] In some embodiments, the electrode assembly further includes a separator disposed between the positive electrode and the negative electrode.

[0094] In some embodiments, the separator is a separator film. The present disclosure does not have a particular limitation on the type of the separator film, and any publicly known porous structure separator film having good chemical stability and mechanical stability can be selected.

[0095] As an example, the main material of the separator film can be selected from at least one of glass fiber, non-woven fabric, polyethylene, polypropylene, and polyvinylidene fluoride, and ceramic.

[0096] In some embodiments, the separator is a solid-state electrolyte. The solid-state electrolyte is disposed between the positive electrode and the negative electrode, and simultaneously functions to transport ions and to separate the positive electrode and the negative electrode.

[0097] In some embodiments, the battery cell further includes an electrolyte, which functions to conduct ions between the positive electrode and the negative electrode. The present disclosure does not have a particular limitation on the type of the electrolyte, and the electrolyte can be selected as needed. The electrolyte can be in a liquid state, a gel state, or a solid state.

[0098] In some embodiments, the electrode assembly is in a jelly-roll structure. The positive electrode sheet and the negative electrode sheet are wound into the jelly-roll structure.

[0099] In some embodiments, the electrode assembly is in a stack structure.

[0100] As an example, a plurality of positive electrode sheets and a plurality of negative electrode sheets can be provided, and the plurality of positive electrode sheets and the plurality of negative electrode sheets can be alternately stacked.

[0101] As an example, a plurality of positive electrode sheets can be provided, and the negative electrode sheet can be folded to form a plurality of folded segments that are stacked. One positive electrode sheet can be interposed between adjacent folded segments.

[0102] As an example, the positive electrode sheet and the negative electrode sheet can each be folded to form a plurality of folded segments that are stacked.

[0103] As an example, the separators can be provided in plurality, each provided between any adjacent positive electrode sheet or negative electrode sheet.

[0104] As an example, the separators can be provided in plurality, each provided between any adjacent positive electrode sheet or negative electrode sheet.

[0105] In some embodiments, the electrode assembly can have a shape of a cylinder, a flat, or a polygonal prism, etc.

[0106] In some embodiments, the electrode assembly can be provided with tabs, which can lead current out of the electrode assembly. The tabs can include positive tabs and negative tabs.

[0107] In some embodiments, the battery cell can include a case. The case can be used to enclose the electrode assembly and other components such as electrolyte. The case can be a steel case, an aluminum case, a plastic case (e.g., polypropylene), a composite metal case (e.g., a copper-aluminum composite case), or an aluminum-plastic film, etc.

[0108] As an example, the battery cell can be a cylindrical battery, a prismatic battery, a pouch battery, or other shapes of batteries, including a square battery, a blade battery, a polygonal battery such as a hexagonal battery, etc., without particular limitation.

[0109] In some embodiments, the case can include a lid and a housing, the housing can be provided with an opening, and the lid can close the opening to form a sealed space for accommodating the electrode assembly and other substances such as electrolyte. The housing can be provided with one or more openings. The lid can also be provided with one or more openings.

[0110] In some embodiments, the case can be provided with a pressure relief mechanism. The pressure relief mechanism can be used to release the internal pressure of the battery.

[0111] In some embodiments, the battery mentioned in the present disclosure can be a battery module, which includes one or more battery cells to provide a single physical module with higher voltage and capacity. When there are multiple battery cells, the multiple battery cells can be connected in series, in parallel, or in a mixed connection through a busbar. The multiple battery cells can be arranged and fixed to form a battery module.

[0112] In some embodiments, the battery mentioned in the present disclosure can also be a battery pack, which includes a box and at least one battery cell or battery module, the battery cell or battery module being accommodated in the box.

[0113] In some embodiments, the box can be part of the chassis structure of a vehicle. For example, part of the box can be at least part of the floor of the vehicle, or part of the box can be at least part of the cross beam and the longitudinal beam of the vehicle.

[0114] Hereinafter, the present disclosure will be described in detail.

[0115] At present, new energy batteries are more and more widely used in life and industry. New energy batteries are not only applied to energy storage power supply systems such as hydroelectric, thermal, wind and solar power stations, but also widely used in electric vehicles such as electric bicycles, electric motorcycles, electric vehicles, electric transportation tools, and aerospace and other fields. With the continuous expansion of the application field of power batteries, not only higher requirements are put forward for the performance and reliability of the battery, but also the demand for lightweight of the battery is also increasing.

[0116] In the process of connecting the tab and the electrode terminal (pole), the tab is pressed against the electrode terminal by the pressing piece, which can reduce the gap between the tab and the electrode terminal, and make the connection of the tab and the electrode terminal more reliable. Through further research, the positioning part located at the outer periphery of the electrode terminal is increased, and the pressing piece is supported by the positioning part, so that the electrode terminal does not need to be increased, thereby not only the weight of the battery is not increased too much, but also the cost of the battery is not increased too much.

[0117] Based on such design concept, the battery cell provided by the present disclosure includes a shell having a plurality of shell walls surrounding an accommodation space, the accommodation space accommodating at least one electrode assembly, the electrode assembly including a tab, and the plurality of shell walls including a first shell wall; an electrode terminal penetrating through the first shell wall and having a first connecting portion located in the accommodation space, the first connecting portion having a connecting surface on a side close to the electrode assembly along a thickness direction of the first shell wall, the connecting surface being connected with the tab; and an insulating piece including a positioning portion, the positioning portion being arranged around an outer periphery of the first connecting portion, the positioning portion having a first surface on a side close to the electrode assembly along the thickness direction of the first shell wall, the first surface being flush with at least a part of the connecting surface close to the positioning portion.

[0118] By having the positioning portion with the first surface and the first surface being flush with at least a part of the connecting surface close to the positioning portion, in the process of connecting the tab and the electrode terminal, the first surface is used to support the pressing piece, and the tab is pressed against the connecting surface by the pressing piece, so that the gap between the tab and the electrode terminal can be reduced without increasing the connecting surface of the electrode terminal, and the connection of the tab and the electrode terminal is more reliable, the connection reliability is improved, and at the same time, the weight of the battery is not increased too much, and the cost is not increased too much, thereby facilitating the lightweight and cost control of the battery. In the prior art, the pressing piece is supported by increasing the connecting surface, which leads to weight increase and high cost.

[0119] The battery provided by the embodiments of the present disclosure can be used in, but is not limited to, electric devices such as energy storage power supply systems, vehicles, ships or aircraft.

[0120] The battery provided by the embodiments of the present disclosure can also be used as a battery pack in groups. The battery pack can also be used in, but is not limited to, electric devices such as energy storage power supply systems, vehicles, ships or aircraft.

[0121] The use 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 automobile, a ship, a spacecraft, etc. The electric toy can include a fixed or mobile electric toy, such as a game console, an electric automobile toy, an electric ship toy, an electric aircraft toy, etc. The spacecraft can include an airplane, a rocket, a space shuttle, a spacecraft, etc.

[0122] In the following embodiments, for the convenience of description, the use device of an embodiment of the present disclosure is taken as a vehicle 1000 for example. The following is described in conjunction with the accompanying drawings.

[0123] FIG. 1 is a structural schematic diagram of a vehicle 1000 provided by some embodiments of the present disclosure. The vehicle 1000 can be a fuel automobile, a gas automobile, or a new energy automobile, which can be a pure electric automobile, a hybrid electric automobile, or a range extended automobile, etc. As shown in FIG. 1, the vehicle 1000 is internally provided with a battery 100, which can be arranged at the bottom, the head, or the tail of the vehicle 1000. The battery 100 can be used for power supply of the vehicle 1000, for example, the battery 100 can be used as an operating power supply of the vehicle 1000. The vehicle 1000 can further include a controller 200 and a motor 300, the controller 200 being used to control the battery 100 to supply power to the motor 300, for example, to meet the working power demand of the vehicle 1000 during starting, navigation, and driving.

[0124] In some embodiments of the present disclosure, the battery 100 can not only be used as an operating power supply of the vehicle 1000, but also be used as a driving power supply of the vehicle 1000, to replace or partially replace fuel or natural gas to provide driving power for the vehicle 1000.

[0125] FIG. 2 is a perspective exploded schematic diagram of a battery provided by some embodiments of the present disclosure. As shown in FIG. 2, the battery 100 includes a box body 2, which includes a lower box body 3 and an upper box body 4, the lower box body 3 and the upper box body 4 being covered together to form a containing space for containing a battery monomer 1.

[0126] In the battery 100, the battery cells 1 can be multiple, and the multiple battery cells 1 can be connected in series, in parallel, or in a mixed connection, where the mixed connection means that the multiple battery cells 1 are connected in series and in parallel. The multiple battery cells 1 can be directly connected in series, in parallel, or in a mixed connection, and the whole of the multiple battery cells 1 is placed in the accommodating space formed by the lower box body 3 and the upper box body 4. Of course, the battery 100 can also be in the form of multiple battery cells 1 connected in series, in parallel, or in a mixed connection to form a battery module, and multiple battery modules are connected in series, in parallel, or in a mixed connection to form a whole, which is accommodated in the accommodating space formed by the lower box body 3 and the upper box body 4. The battery 100 can also include other structures, for example, the battery 100 can also include a current collecting component for realizing the electrical connection between the multiple battery cells 1.

[0127] In the following, some embodiments of the present disclosure will be described in detail with reference to FIGS. 3 to 11.

[0128] FIG. 3 is a perspective exploded schematic view of a battery cell according to some embodiments of the present disclosure; FIG. 4 is a schematic view of the structure of an electrode assembly and an end cover connected together according to some embodiments of the present disclosure; and FIG. 5 is a schematic view of the structure of an electrode assembly and an end cover exploded according to some embodiments of the present disclosure. The positional relationship between the electrode assembly 30 and the end cover shown in FIG. 4 can be regarded as a view angle of the electrode assembly 30 in FIG. 3 flattened in an end-to-end state in a direction away from each other with two sides opposite to each other, at this time, the tab 32 of the electrode assembly 30 is flattened from the bent shape in FIG. 3 to a flat shape. It can also be regarded as a view angle in the process of connecting the tab 32 and the electrode terminal 22 in the process of manufacturing the battery.

[0129] FIG. 6 is a schematic view of a part of the structure of the electrode assembly in FIG. 5; and FIG. 7 is a schematic view of a part of the structure of the electrode assembly according to another embodiment of the present disclosure. The tab 32 of the electrode assembly 30 in FIGS. 6 and 7 is in a view angle in an unbent state, and the view angle of the tab 32 in a bent state can be seen with reference to the electrode assembly 30 shown in FIG. 3.

[0130] FIG. 8 is a schematic view of the structure of an end cover according to some embodiments of the present disclosure, in which two electrode terminals 22 are respectively provided with a pressing piece S; FIG. 9 is a top view of an end cover according to some embodiments of the present disclosure, in which one of the two electrode terminals 22 is provided with a pressing piece S, and the other is not provided with a pressing piece; FIG. 10 is a schematic view of a part of the cross section of an end cover according to some embodiments of the present disclosure, in which the electrode terminal 22 is not provided with a pressing piece S; and FIG. 11 is a schematic view of a cross section of a pressing piece pressing the tab to the electrode terminal according to some embodiments of the present disclosure.

[0131] In the embodiments of the present disclosure, the direction in which the arrow Z is located in the diagram is defined as a first direction Z, the direction in which the arrow Y is located is defined as a second direction Y, and the direction in which the arrow X is located is defined as a third direction X. The first direction Z, the second direction Y, and the third direction X are perpendicular to each other.

[0132] In some embodiments, the direction in which the arrow X is located can also represent the stacking direction X of the plurality of tab pieces 32a, the thickness direction X of the end cover, the direction in which the arrow Y is located can also represent the width direction Y of the end cover, and the direction in which the arrow Z is located can also represent the length direction Z of the main body part 31 and the length direction Z of the end cover. In addition, those skilled in the art can understand that the main body part 31 in FIGS. 4 to 7 is a flattened perspective view of the main body part 31 in FIG. 3, and therefore, the thickness direction of the main body part 31 in FIGS. 4 to 7 is the same as the thickness direction of the folding part 322, and the thickness direction of the main body part 31 in FIG. 3 is perpendicular to the thickness direction of the folding part 322.

[0133] The embodiments of the present disclosure provide a battery monomer 1, which includes a shell 10 having a plurality of shell walls surrounding an accommodation space A, the accommodation space A containing at least one electrode assembly 30, the electrode assembly 30 including a tab 32, and the plurality of shell walls including a first shell wall 12; an electrode terminal 22 penetrating the first shell wall 12 and having a first connecting part 221 located in the accommodation space A, the first connecting part 221 having a connecting surface 221a close to the electrode assembly 30 along a first shell wall thickness direction X, the connecting surface 221a being connected to the tab 32; and an insulating part 23 including a positioning part 231 arranged around the outer periphery of the first connecting part 221, the positioning part 231 having a first surface 231a close to the electrode assembly 30 along the first shell wall thickness direction X, the first surface 231a being flush with at least a portion of the connecting surface 221a close to the positioning part 231.

[0134] The shell 10 has a plurality of shell walls surrounding an accommodation space A, and the accommodation space A contains the electrode assembly 30. In addition, the accommodation space can also contain electrolyte and other components. The plurality of shell walls includes a first shell wall 12. The shell 10 can be a shell 10 without an end cover, so that the first shell wall 12 is a part of the shell 10. The first shell wall 12 can be any side wall or any end wall of the shell 10. The shell 10 can be a shell 10 with an end cover, so that the first shell wall 12 can be referred to as an end cover.

[0135] As an example, referring to FIG. 3, the shell 10 is a shell 10 with an end cover, specifically, the shell 10 includes a shell body 11 and a first shell wall 12 (end cover), and the first shell wall 12 closes the opening to form an accommodation space containing at least one electrode assembly 30.

[0136] The shell 11 can have various shapes, such as a cuboid shape, a cylindrical shape, a hexagonal prism shape, etc., and a suitable shell 11 can be determined according to the specific shape of the electrode assembly 30.

[0137] The shell 11 can be made of a metal material or a non-metal material, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, aluminum plastic, etc., and the present disclosure does not make special limitations on this.

[0138] The shape of the first shell wall 12 can be adapted to the shape of the opening of the shell 11. The first shell wall 12 can be made of various materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the present disclosure does not make special limitations on this.

[0139] For example, the first shell wall 12 can be made of a material with certain hardness and strength, such as aluminum alloy, so that the first shell wall 12 is not easily deformed when subjected to extrusion and collision, allowing the battery monomer 1 to have higher structural strength. The first shell wall 12 can be provided with a pressure relief mechanism for relieving the internal pressure when the internal pressure of the battery monomer 1 reaches a threshold value.

[0140] The number of electrode assemblies 30 can be one, two or more. For example, referring to FIG. 3, two electrode assemblies 30 are provided, and the two electrode assemblies 30 are oppositely arranged along the thickness direction X of the electrode assembly 30. In some embodiments, each electrode assembly 30 includes a main body part 31 (shown in FIG. 5) and a tab 32 provided on the main body part 31, and the main body part 31 includes a positive electrode tab, a negative electrode tab, and a separator interposed between the positive electrode tab and the negative electrode tab. In one example, the positive electrode tab, the separator, and the negative electrode tab can be wound at least two turns to form a wound structure; in another example, the positive electrode tab, the separator, and the negative electrode tab can also be stacked to form a laminated structure. The tab 32 can conduct current from the main body part 31. The tab 32 can be directly connected to the electrode terminal 22 or connected through an adapter piece.

[0141] The electrode terminal 22 is provided on the first shell wall 12 and is used to connect with the tab 32 to output and input electric energy. When there are multiple battery monomers 1, the electrode terminals 22 of each battery monomer 1 can also be connected through a busbar component, so that the multiple battery monomers 1 are connected in series and / or in parallel. The material of the electrode terminal 22 can be various conductive metals, such as copper, iron, aluminum, stainless steel, aluminum alloy, etc. For example, the electrode terminal 22 sometimes exists in the form of a pole.

[0142] The electrode terminal 22 penetrates the first shell wall 12 and has a first connecting portion 221 located in the accommodation space A. The electrode terminal 22 can have the first connecting portion 221 at least partially protruding from the first shell wall 12 along the first shell wall thickness direction X (the third direction X), i.e., along the first shell wall thickness direction X, the first connecting portion 221 has a height H1 exceeding the first shell wall 12. Referring to FIG. 11, the height H1 is the distance between the surface (connecting surface 221a) of the first connecting portion 221 away from the first shell wall 12 along the first shell wall thickness direction X and the surface of the first shell wall 12 away from the electrode assembly 30. For example, referring to FIGS. 3 and 11, along the first shell wall thickness direction X, part of the first connecting portion 221 protrudes from the first shell wall 12 and is located in the accommodation space A, and the other part extends through the first shell wall 12 to the outside of the shell 10 and is connected with a second connecting portion 222, which can be used to connect an external bus member.

[0143] The first connecting portion 221 has a connecting surface 221a located on the side close to the electrode assembly 30 along the first shell wall thickness direction X, and the first connecting portion 221 is connected with the tab 32 through the connecting surface 221a.

[0144] The connecting surface 221a can be directly connected with the tab 32. The connection mode can be welding, bonding, or the like. The shape of the connecting surface 221a can be square, circular, oval, or other shapes. Directly connecting the tab 32 with the connecting surface 221a can shorten the overcurrent path and reduce the impedance during charging and discharging of the battery monomer 1. In addition, the adapter tab can be omitted, so that the battery monomer 1 and even the battery 100 are more lightweight.

[0145] The insulating member 23 is used to isolate the electrode terminal 22 from the first shell wall 12 to reduce the risk of short circuit. The material of the insulating member 23 can be plastic, rubber, or other materials with insulating properties.

[0146] The insulating member 23 includes a positioning portion 231 arranged around the outer periphery of the first connecting portion 221. The positioning portion 231 can protrude from the first shell wall 12 on the same side as the first connecting portion 221 along the first shell wall thickness direction X. The positioning portion 231 can completely or partially surround the first connecting portion 221, and play a positioning and insulating role for the first connecting portion 221. For example, the positioning portion 231 is in a closed ring shape and surrounds the outer periphery of the first connecting portion 221.

[0147] The positioning portion 231 has a first surface 231a on the side close to the electrode assembly 30 along the first shell wall thickness direction X, and the first surface 231a is flush with at least the portion of the connecting surface 221a close to the positioning portion 231. The first surface 231a being flush with at least the portion of the connecting surface 221a close to the positioning portion 231 can be understood as the first surface 231a being slightly lower than, slightly higher than, or flush with the connecting surface 221a along the first shell wall thickness direction X, and the height difference between the two can be within the range allowed by the machining error or measurement error.

[0148] The first surface 231a can be understood as having a specified extension along the first direction Z (the first shell wall length direction) and / or the second direction Y (the first shell wall width direction), so that when the presser S presses the tab 32 against the electrode terminal 22, the first surface 231a can provide sufficient support space for the presser S to support the presser S. As for the range of the extension, it can be determined based on the size of the presser, so that the support space formed by the first surface 231a can reach the extent of supporting the presser S.

[0149] The first surface 231a supporting the presser S can be understood as follows: when the presser S presses the tab 32, the presser S can be fully supported by the first surface 231a, i.e., the pressing surface of the presser S is entirely located on the first surface 231a; or, a part of the presser S is supported by the first surface 231a, i.e., a part of the pressing surface of the presser S is located on the first surface 231a, for example, referring to FIG. 11, a part of the pressing surface of the presser S is supported by the first surface 231a, and the other part is supported by the connecting surface 221a of the first connecting portion 221, i.e., the first surface 231a of the positioning portion 231 and the connecting surface 221a of the first connecting portion 221 jointly support the presser S. Of course, the presser S can also be fully supported by the first surface 231a.

[0150] As an example, referring to FIGS. 9, 10 and 11, in the process of directly welding the tab 32 to the electrode terminal 22, first, the presser S supported by the first surface 231a and the connecting surface 221a presses the tab 32 against the connecting surface 221a, so that the tab 32 is in contact with the connecting surface 221a, and the presser S is wrapped around the area to be welded between the tab 32 and the connecting surface 221a, for example, the center of the presser S can be generally coincident with the center of the connecting surface 221a, then the welding head is inserted into the annular space of the presser S and performs welding operation on the tab 32 and the connecting surface 221a, so that the connecting surface 221a and the tab 32 are firmly welded together. The presser S can also reduce the splashing of particulate matter during welding and reduce the risk of short circuit of the battery monomer 1.

[0151] The first face 231a is used to support the pressing piece S in the process of connecting the tab 32 and the electrode terminal 22, and the pressing piece S is used to press the tab 32 against the connecting face 221a, so that the gap between the tab 32 and the electrode terminal 22 is reduced, and the connection between the tab 32 and the electrode terminal 22 is more reliable, thereby improving the connection reliability. In addition, the electrode terminal 22 does not need to be increased in size, which not only does not increase the weight of the battery too much, but also does not increase the cost too much, thereby being beneficial to the light weight and cost control of the battery monomer 1 and even the battery 100. In the prior art, the pressing piece S is supported by increasing the size of the electrode terminal 22, which leads to an increase in the weight of the battery monomer 1 and high cost.

[0152] In some embodiments, referring to FIGS. 9, 10 and 11, the pressing piece S has a pressing face S1 used to press the tab 32 against the connecting face 221a, the size of the connecting face 221a along the first shell wall length direction Z is D1, the size of the first face 231a along the first shell wall length direction Z is D2, the size of the pressing face S1 along the first shell wall length direction Z is D3, the size of the connecting face 221a along the first shell wall width direction Y is W1, the size of the first face 231a along the first shell wall width direction Y is W2, and the size of the pressing face S1 along the first shell wall width direction Y is W3, wherein D1+2D2≥D3 and W1+2W2≥W3.

[0153] D3 can be the distance between two opposite outer edges of the pressing piece S along the first shell wall length direction Z, and W3 can be the distance between two opposite outer edges of the pressing piece S along the first shell wall width direction Y. The size D2 of the positioning portion 231 along the first shell wall length direction Z and the size W2 along the first shell wall width direction Y can be adjusted according to the size of the pressing piece S.

[0154] In the process of connecting the tab 32 and the electrode terminal 22, the tab 32 is pressed against the connecting face 221a of the first connecting portion 221 by the pressing piece S, and due to D1+2D2≥D3 and W1+2W2≥W3, at least part of the pressing piece S is supported by the first face 231a of the positioning portion 231, so that the tab 32 is more closely pressed against the connecting face 221a of the first connecting portion 221, thereby improving the connection reliability.

[0155] In some embodiments, the absolute value of the height difference between the first face 231a and the connecting face 221a along the thickness direction X of the first shell wall is in the range of 0mm to 0.3mm.

[0156] The first surface 231a can be slightly lower than, slightly higher than, or flush with the connecting surface 221a, and the height difference between the two can be within the error range allowed by processing.

[0157] Controlling the height difference between the first surface 231a and the connecting surface 221a within a suitable error range enables the pressing member S to more evenly press the tab 32 against the connecting surface 221a, improving connection reliability.

[0158] In some embodiments, the thickness of the first surface 231a along the length direction Z of the first housing wall and / or the width direction Y of the first housing wall is greater than or equal to 1 mm and less than or equal to 3 mm.

[0159] In the prior art, the thickness of the positioning portion 231 is generally less than 1 mm, and only serves the purpose of positioning the first connecting portion 221. The positioning portion 231 of the present disclosure not only serves the purpose of positioning the first connecting portion 221, but also has the function of supporting the pressing member S, thereby enabling the pressing member S to more evenly press the tab 32 against the first connecting portion 221, facilitating subsequent welding, reducing the risk of false welding, and improving connection reliability.

[0160] In some embodiments, the electrode terminal 22 further includes a second connecting portion 222 located outside the housing 10 along the thickness direction X of the first housing wall, and the second connecting portion 222 is connected to the first connecting portion 221. The second connecting portion 222 can be riveted to the first connecting portion 221 or the two can be formed as an integral structure.

[0161] The second connecting portion 222 can be used to connect external bus members, and through the bus members, multiple battery monomers 1 can be connected together to form a battery module, improving the capacity of the battery and meeting the demand for high-power electricity consumption.

[0162] In some embodiments, the electrode terminal 22 includes a terminal plate 2221 and a terminal disc 2211 connected to each other, the first connecting portion 221 includes the terminal disc 2211, and the terminal disc 2211 includes the connecting surface 221a. The terminal plate 2221 and the terminal disc 2211 can be riveted or formed as an integral structure.

[0163] The terminal disc 2211 is disc-shaped, such as a circular disc or an elliptical disc, and can be made of copper, iron, aluminum, stainless steel, aluminum alloy, or other conductive metals.

[0164] The terminal disc 2211 includes the connecting surface 221a, which is generally planar, enabling the connecting surface 221a to be more closely attached to the tab 32, facilitating subsequent connection, and improving connection reliability.

[0165] In some embodiments, the second connecting portion 222 includes the terminal plate 2221.

[0166] The terminal plate 2221 is plate-shaped, and has a flat surface that can be used to connect with the busbar component. The shape of the terminal plate 2221 can be circular, square, or other shapes. The material of the terminal plate 2221 can be the same as or different from the material of the terminal disc 2211.

[0167] The second connecting portion 222 includes the terminal plate 2221, so that the connecting surface 221a is more closely attached to the busbar component, facilitating subsequent connection and improving connection reliability.

[0168] In some embodiments, the positioning portion 231 has a second surface 231b that is arranged around the outer periphery of the first connecting portion 221 and is in contact with the outer surface of the first connecting portion 221.

[0169] The shape of the positioning portion 231 can be adapted to the shape of the first connecting portion 221. Since the positioning portion 231 is flush with the first connecting portion 221 along the thickness direction of the first shell wall 12, the positioning portion 231 more stably surrounds the first connecting portion 221, improving positioning stability and reducing the risk of the tab 32 shaking during connection (such as welding) with the first connecting portion 221, which is conducive to connection reliability.

[0170] In some embodiments, the insulating member 23 further includes a portion 232 (shown in FIG. 10) located between the first connecting portion 221 and the first shell wall 12 along the thickness direction X of the first shell wall.

[0171] The portion 232 located between the first connecting portion 221 and the first shell wall 12 is used to isolate the first connecting portion 221 and the first shell wall 12, reducing the risk of short circuit. It can be understood that the portion 232 located between the first connecting portion 221 and the first shell wall 12 has a through hole for the first connecting portion 221 to pass through.

[0172] In some embodiments, the insulating member 23 further includes a protruding portion 233 protruding towards the electrode assembly 30 side along the thickness direction X of the first shell wall.

[0173] The protruding portion 233 can be used to abut against the main body portion 31 of the electrode assembly 30, reducing the risk of the electrode assembly 30 shaking.

[0174] For example, the first shell wall 12 (such as the end cover) is further provided with a pressure relief valve and a liquid injection hole, and the insulating member 23 includes an insulating body, and the insulating body is provided with a pressure relief valve avoiding hole 234 corresponding to the pressure relief valve and a liquid injection avoiding hole 235 corresponding to the liquid injection hole.

[0175] In some embodiments, the tab 32 is directly welded with the connecting surface 221a.

[0176] In the process of connecting the tab 32 and the electrode terminal 22, the pressing piece S can press the tab 32 against the electrode terminal 22, so that the tab 32 is more closely attached to the connecting surface 221a, thereby reducing the risk of false welding and improving the connection reliability. The tab 32 and the connecting surface 221a can be connected by laser welding, which not only achieves reliable connection, but also improves processing efficiency. The laser welding mark can play a role in overcurrent protection.

[0177] In some embodiments, along the first shell wall thickness direction X, the tab 32 has a portion at least overlapping the connecting surface 221a.

[0178] Along the first shell wall thickness direction X, a part or all of the tab 32 overlaps the connecting surface 221a. The tab 32 can cover all or part of the connecting surface 221a.

[0179] By having a portion of the tab 32 overlapping the connecting surface 221a, the overcurrent path of the tab 32 is shortened, the impedance is reduced, the battery temperature is reduced, and the battery performance and reliability are improved.

[0180] In some embodiments, along the thickness direction of the tab 32, the tab 32 has a portion overlapping the connecting surface 221a and a portion overlapping the first surface 231a.

[0181] The tab 32 has a portion overlapping the first surface 231a, which can increase the pressing area of the pressing piece S pressing the tab, so that the tab 32 is more closely attached to the connecting surface 221a of the electrode terminal 22, which helps to improve the connection reliability of the tab 32 and the electrode terminal 22.

[0182] In some embodiments, along the thickness direction of the tab 32, the first surface 231a abuts against the tab 32.

[0183] The first surface 231a abuts against the tab 32, which supports the tab 32 together with the connecting surface 221a, reduces the risk of deformation of the tab 32, and helps to improve the connection reliability of the tab 32 and the electrode terminal 22.

[0184] In some embodiments, referring to FIGS. 3-7, the electrode assembly 30 includes a main body 31, the tab 32 is arranged on the main body 31, the tab 32 includes a plurality of tab pieces 32a, the tab 32 has a connecting portion 321 and a folding portion 322, the connecting portion 321 is connected between the main body 31 and the folding portion 322, the connecting portion 321 is folded towards the folding portion 322, and the folding portion 322 is formed by stacking and connecting the plurality of tab pieces 32a together, and the folding portion 322 is directly connected to the electrode terminal 22.

[0185] The body part 31 comprises a positive electrode tab, a negative electrode tab and a separator interposed between the positive electrode tab and the negative electrode tab. In one example, the positive electrode tab, the separator and the negative electrode tab can be wound at least two turns to form a wound structure; in another example, the positive electrode tab, the separator and the negative electrode tab can also be laminated to form a laminated structure.

[0186] The tab 32 comprises a plurality of tab pieces 32a, each of which is connected to the body part 31, and each of which can be integrated with the body part 31 or can be a separate structure. The separate structure can be, for example, that each tab piece 32a is connected to the body part 31 by welding.

[0187] The tab 32 can conduct current from the body part 31. The tab 32 comprises a plurality of tab pieces 32a, which can improve the current-carrying capacity and better adapt to the fast charging and high-power power consumption requirements of the battery.

[0188] The tab 32 has a connecting part 321 and a folding part 322, the connecting part 321 is connected between the body part 31 and the folding part 322, the connecting part 321 is folded towards the folding part 322, and the folding part 322 is connected together by lamination of a plurality of tab pieces 32a, and the folding part 322 is directly connected to the electrode terminal 22.

[0189] The folding part 322 is connected together by lamination of a plurality of tab pieces 32a, which means that the plurality of tab pieces 32a are laminated in the thickness direction of the tab pieces 32a and are in close contact with each other between the tab pieces 32a, so that the folding part 322 is formed as a compact integrated structure.

[0190] The folding part 322 is connected together by lamination of a plurality of tab pieces 32a, which means that the plurality of tab pieces 32a are laminated in the thickness direction of the tab pieces 32a and are in close contact with each other between the tab pieces 32a, so that the folding part 322 is formed as a compact integrated structure.

[0191] After the electrode assembly 30 is wound to form a wound structure, the plurality of tab pieces 32a can be loose, and the gap between the tab pieces 32a in the lamination direction (third direction X in FIG. 6) is large, and the loose tab pieces 32a are connected to the electrode terminal 22, which can cause the connection to be not firm, for example, there is a risk of false welding during the welding process, resulting in poor current-carrying capacity and failing to meet the high-rate charging and discharging requirements.

[0192] To this end, the plurality of loose tab pieces 32a are concentrated towards the same position and stacked on each other to form a compacted portion 322, which is directly connected (e.g. laser welded) to the electrode terminal 22, and reliable connection can be achieved. As an example, the compacted portion 322 can have a plate-like structure similar to the conventional adapter tab, so that when the compacted portion 322 is directly connected (e.g. laser welded) to the electrode terminal 22, the same connection effect as the adapter tab and the electrode terminal 22 can be basically achieved.

[0193] The compacted portion is connected together by the plurality of tab pieces 32a to form a compacted integrated structure, so that the compacted portion 322 is more firmly connected to the electrode terminal 22, the risk of false connection is reduced, and the overcurrent capacity of the tab 32 is improved. That is, even if the conventional adapter tab is omitted, the overcurrent capacity of the tab 32 can be improved to meet the high-rate charging and discharging requirements without reducing the connection effect of the tab 32 and the electrode terminal 22, and the impedance during charging and discharging of the battery monomer 1 can be reduced, thereby reducing the temperature rise, alleviating the adverse effects of high temperature of the battery monomer 1 on performance and cycle life, and reducing the risk of thermal runaway of the battery monomer 1, thereby improving the reliability of the battery monomer 1 and even the battery 100.

[0194] In some embodiments, the compacted portion 322 is formed with a first welding connection portion 322c, the plurality of tab pieces 32a are connected together by the first welding connection portion 322c, and the compacted portion 322 and the electrode terminal 22 are connected to each other by a second welding connection portion 322b. In the same projection plane perpendicular to the thickness direction X of the compacted portion 322, the projection of the second welding connection portion 322b and the first welding connection portion 322c has an overlapping portion.

[0195] In the same projection plane perpendicular to the thickness direction X of the compacted portion 322, the projection of the second welding connection portion 322b and the first welding connection portion 322c has an overlapping portion, which can be understood as that in the compacted portion 322, the plurality of tab pieces 32a are connected together by welding to form a first welding connection portion 322c having a certain area, and the compacted portion 322 and the electrode terminal 22 are connected together by welding within the area of the first welding connection portion 322c to form a second welding connection portion 322b.

[0196] For example, first, the plurality of tab pieces 32a located in the gathered portion 322 can be ultrasonic pre-welded, thereby forming a first welded connection portion 322c (ultrasonic weld) in the gathered portion 322, which tightly connects the plurality of tab pieces 32a located in the gathered portion 322 together to form an integrated structure. Then, the gathered portion 322 is connected with the electrode terminal 22 by laser welding in the area of the first welded connection portion 322c, thereby forming a second welded connection portion 322b (laser weld) between the gathered portion 322 and the electrode terminal 22, which at least partially overlaps with the first welded connection portion 322c.

[0197] Thus, the plurality of tab pieces 32a are connected as an integrated structure by the first welded connection portion 322c, which makes the connection between the plurality of tab pieces 32a located in the gathered portion more solid, and the projection of the second welded connection portion 322b and the first welded connection portion 322c have overlapping parts, which makes the connection between the gathered portion 322 and the electrode terminal 22 connected by the second welded connection portion 322b more reliable, reduces the risk of false welding, thereby improving the overcurrent capacity during high-rate charging and discharging, and also reduces the temperature rise.

[0198] In some embodiments, in the same projection plane perpendicular to the thickness direction X of the gathered portion 322, the projection of the second welded connection portion 322b does not exceed the projection of the first welded connection portion 322c.

[0199] Thus, all the second welded connection portions 322b are located in the area of the first welded connection portion 322c, further improving the connection reliability between the gathered portion 322 and the electrode terminal 22.

[0200] In some embodiments, the area of the projection of the second welded connection portion 322b accounts for 30% to 100% of the area of the projection of the first welded connection portion 322c. For example, the area of the projection of the second welded connection portion 322b accounts for 30%, 35%, 40%, 45%, 50%, 55%, 60%, 70%, 80%, 90%, 100% of the area of the projection of the first welded connection portion 322c.

[0201] The welding area between the gathered portion 322 and the electrode terminal 22 is in a suitable range, which can meet the overcurrent requirement and also play the role of overcurrent protection.

[0202] In some embodiments, the gathered portion 322 is configured as a plate structure.

[0203] The plate structure can be rectangular, square, oval, or other shapes.

[0204] The inner structure of the converging portion 322 of the plate-shaped structure is more compact, so that when the converging portion 322 is directly connected with the electrode terminal 22, the effect of connecting the converging portion 322 with the electrode terminal 22 is more close to the effect of connecting the conventional adapter tab with the electrode terminal 22, thereby further improving the overcurrent capacity and the connection reliability.

[0205] In some embodiments, the converging portion 322 and the electrode terminal 22 have an overlapping portion along the layer thickness direction X of the converging portion 322.

[0206] The converging portion 322 and the electrode terminal 22 are overlapped with each other along the layer thickness direction X of the converging portion 322, and the converging portion 322 can be entirely overlapped with the electrode terminal 22 or partially overlapped with the electrode terminal 22.

[0207] Therefore, the overcurrent path of the tab 32 can be further shortened, the impedance can be reduced, the battery temperature can be further reduced, and the battery performance and reliability can be improved.

[0208] In some embodiments, the end of the connecting portion 321 connected with the converging portion 322 is located on one side of the thickness direction center O of the main body portion 31 (as shown in FIG. 7) or at the thickness direction center O of the main body portion 31 (as shown in FIG. 6).

[0209] Referring to FIG. 7, the plurality of tab pieces 32a are all gathered together towards one side of the thickness direction center O of the main body portion 31 to form the converging portion 322 deviated from the center O.

[0210] The plurality of tab pieces 32a form the centrally-located converging portion 322, which helps to reduce the internal resistance of the battery monomer 1, reduce the temperature rise of the battery monomer 1 during high-rate discharge, and improve the battery performance and reliability.

[0211] Referring to FIG. 6, the end of the connecting portion 321 connected with the converging portion 322 is generally located at the thickness direction center O of the main body portion 31.

[0212] The plurality of tab pieces 32a are all gathered together towards the thickness direction (X direction in FIG. 6, Y direction in FIG. 3) center O of the main body portion 31 to form the centrally-located converging portion 322. The end of the connecting portion 321 connected with the converging portion 322 being generally located at the thickness direction center O of the main body portion 31 is to be understood in a broad sense, and it can be understood within the range of allowable manufacturing or measurement errors.

[0213] Therefore, the converging portion 322 of the tab 32 is centrally located, so that the overcurrent paths of the plurality of tab pieces 32a are substantially the same, the overcurrent is more uniform, the temperature rise of the battery monomer 1 during high-rate charge and discharge can be reduced, and therefore the cycle life of the battery monomer 1 can be significantly improved. In addition, the centrally-located structure of the tab 32 facilitates welding with the electrode terminal 22.

[0214] In some embodiments, referring to FIGS. 4 and 5, the electrode terminal 22 includes a positive electrode terminal 22a and a negative electrode terminal 22b; the tab 32 includes a positive electrode tab 32c and a negative electrode tab 32d, the positive electrode tab 32c and the negative electrode tab 32d are arranged at the same end of the main body 31, the positive electrode tab 32c is directly connected to the positive electrode terminal 22a, and the negative electrode tab 32d is directly connected to the negative electrode terminal 22b.

[0215] The positive electrode terminal 22a and the negative electrode terminal 22b are arranged at intervals along the length direction Z of the end cover. The positive electrode tab 32c and the negative electrode tab 32d are arranged at intervals along the length direction Z of the electrode assembly 30 and are drawn out from the same end of the main body 31. The positive electrode tab 32c includes a plurality of positive electrode tab pieces that are connected together in layers to form a positive electrode folding portion, and the positive electrode folding portion is directly connected to the positive electrode terminal 22a. The negative electrode tab 32d includes a plurality of negative electrode tab pieces that are connected together in layers to form a negative electrode folding portion, and the negative electrode folding portion is directly connected to the negative electrode terminal 22b.

[0216] The positive electrode tab 32c and the negative electrode tab 32d are directly connected to the positive electrode terminal 22a and the negative electrode terminal 22b, respectively, which can reduce the internal impedance of the battery, reduce the temperature rise during charging and discharging of the battery, and improve the reliability of the battery. In addition, the positive electrode tab 32c and the negative electrode tab 32d are arranged at the same end of the main body 31, which helps to improve the utilization rate of the shell space, thereby improving the volume energy density of the battery monomer 1.

[0217] In some embodiments, at least two electrode assemblies 30 are provided, the tabs of the at least two electrode assemblies 30 have the same polarity and are connected together, and the tabs 32 of each electrode assembly 30 are directly connected to the electrode terminal 22 through the respective folding portion 322.

[0218] The at least two electrode assemblies 30 are directly connected to the electrode terminal 22 through the respective folding portion 322, which can reduce the internal impedance of the battery monomer 1, reduce the temperature rise during charging and discharging of the battery, improve the reliability of the battery, and also improve the capacity of the battery, and can better meet the demand for high-rate discharge.

[0219] In the following, specific examples of the embodiments of the present disclosure will be described with reference to FIGS. 3 to 11.

[0220] The battery monomer 1 of the embodiments of the present disclosure includes a shell 10, an electrode terminal 22, and an electrode assembly 30.

[0221] The shell 10 includes a plurality of shell walls, including a first shell wall 12 among the plurality of shell walls, and the remaining shell walls surround a shell body 11 having an opening. The first shell wall 12 can be an end cover of the battery monomer 1, and the first shell wall 12 closes the opening to form an accommodation space A for accommodating the electrode assembly 30 with the shell body 11.

[0222] Referring to Figs. 8 to 11, the electrode terminal 22 is provided on the first housing wall 12, and the insulating member 23 is provided between the first housing wall 12 and the housing 11. The electrode terminal 22 includes a first connecting portion 221 penetrating through the first housing wall 12 and protruding from the first housing wall 12 toward the side of the first housing wall 12 along the thickness direction X of the first housing wall 12 close to the electrode assembly 30 (shown in Fig. 3), and a second connecting portion 222 protruding from the first housing wall 12 toward the side of the first housing wall 12 along the thickness direction X of the first housing wall 12 away from the electrode assembly 30, and the second connecting portion 222 is riveted with the first connecting portion 221.

[0223] The insulating member 23 includes a positioning portion 231 protruding from the first housing wall 12 toward the side of the first housing wall 12 along the thickness direction X of the first housing wall 12 close to the electrode assembly 30 (shown in Fig. 1), and the positioning portion 231 is provided around the outer periphery of the first connecting portion 221, and plays a role of positioning the first connecting portion 221. The positioning portion 231 has a first surface 231a close to the electrode assembly 30 along the thickness direction X of the first housing wall, and the first connecting portion 221 has a connecting surface 221a close to the electrode assembly 30 along the thickness direction X of the first housing wall, and the first surface 231a is flush with the connecting surface 221a. Specifically, the height of the first connecting portion 221 protruding from the first housing wall 12 is H1, and the height of the positioning portion 231 protruding from the first housing wall 12 is H2, and the difference between H1 and H2 is within the range of 0 mm to 0.3 mm. The first connecting portion 221 is directly welded with the tab 32 of the electrode assembly 30 through the connecting surface 221a, and in the connecting process of the tab 32 and the first connecting portion 221, the first surface 231a is used to support the pressing member S, so that the pressing member S presses the tab 32 on the connecting surface 221a of the first connecting portion 221.

[0224] Referring to Figs. 3 to 5, each electrode assembly 30 includes a main body portion 31 and two tabs 32 provided on the main body portion 31 and respectively led out from the same end of the main body portion 31, and each tab 32 includes a plurality of tab pieces 32a, and the tab 32 has a connecting portion 321 connected between the main body portion 31 and a gathered portion 322, and the gathered portion 322 is connected together via the plurality of tab pieces 32a by ultrasonic welding to form a compact and integral plate-like structure, and an ultrasonic welding mark is formed on the gathered portion 322, and along the thickness direction X of the gathered portion 322, the gathered portion 322 has an overlapping portion with the electrode terminal 22, and the connecting surface 221a of the electrode terminal 22 is directly connected with the gathered portion 322 by laser welding, and a laser welding mark (second welding connecting portion 322b shown in Fig. 4) is formed on the gathered portion 322. Among them, the laser welding mark coincides with the ultrasonic welding mark, and the gathered portion 322 is arranged to be bent relative to the connecting portion 321, and the main body portions 31 of the two electrode assemblies 30 are arranged face to face along the thickness direction Y (shown in Fig. 3).

[0225] First, the plurality of tab pieces 32a of each electrode assembly 30 are brought together toward the same position and stacked together by an ultrasonic welding device to form a tab 32 having a gathered portion 322 and a connecting portion 321, so that the gathered portion 322 is configured as a compact unitary plate structure, and an ultrasonic weld is formed on the gathered portion 322; then, the compact gathered portion 322 of the electrode assembly 30 is stacked on the connecting surface 221a of the first connecting portion 221 of each electrode terminal 22 along the layer thickness direction X; next, the gathered portion 322 is pressed against the connecting surface 221a by a ring-shaped pressing member S, which is supported by the connecting surface 221a and the first surface 231a together, so that the gathered portion 322 is attached to the connecting surface 221a; after that, a welding head is inserted into the interior of the pressing member S to perform laser welding at the position of the ultrasonic weld of the gathered portion 322 to weld the gathered portion 322 and the connecting surface 221a together, thereby completing the welding operation of the tab 32 of the electrode assembly 30 and the electrode terminal 22. After that, the pressing member S is removed, and the two main body portions 31 are each rotated 90 degrees toward each other, so that they are arranged face to face along the thickness direction (shown in FIG. 3), so that the gathered portion 322 is bent relative to the connecting portion 321, and then the two electrode assemblies 30 are placed into the housing 10 with the first housing wall 12 closing the opening of the housing 10.

[0226] The present disclosure also provides a battery 100 including the case 2 and at least one battery cell 1 mentioned above.

[0227] Referring to FIG. 2, the case 2 includes a lower case 3 and an upper case 4, which are overlapped with each other to form a receiving space for receiving the battery cell 1.

[0228] The present disclosure also provides an electric device including the battery cell 1 or the battery 100 mentioned above for providing electric energy.

[0229] The present disclosure also provides an energy storage device including the battery cell 1 or the battery 100 mentioned above for providing electric energy, which is capable of storing and providing electric energy.

[0230] The energy storage device can be an energy storage case or an energy storage cabinet. The energy storage cabinet includes a plurality of battery compartments for receiving the battery cell 1. In addition, the energy storage cabinet can also include a thermal management assembly, a power control assembly, etc.

[0231] Next, the battery cell manufacturing method of some embodiments of the present disclosure will be described in detail with reference to FIGS. 12-13.

[0232] Referring to FIG. 12, the present disclosure also provides a battery cell manufacturing method, the battery cell 1 including an electrode assembly 30, a first housing wall 12, an electrode terminal 22 and an insulating member 23 mounted to the first housing wall 12, the electrode assembly 30 including a tab 32, the battery manufacturing method including:

[0233] S001 tab positioning step, pressing the tab 32 to the first connecting part 221 of the electrode terminal 22 by the pressing piece S, wherein the first connecting part 221 has a connecting surface 221a, the electrode terminal 22 is positioned in the positioning part 231 of the insulating piece 23, the positioning part 231 surrounds the outer periphery of the first connecting part 221, and the positioning part 231 has a first surface 231a flush with the connecting surface 221a, and the pressing piece S is at least partially supported on the first surface 231a;

[0234] S002 tab connecting step, connecting the tab 32 pressed on the connecting surface 221a to the first connecting part 221.

[0235] Supporting the pressing piece S by the first surface 231a and pressing the tab 32 to the electrode terminal 22 by the pressing piece S can reduce the gap between the tab 32 and the electrode terminal 22, and further make the connection between the tab 32 and the electrode terminal 22 more reliable, thereby improving the connection reliability, without significantly increasing the weight of the battery monomer 1 and the cost. If the support space for the pressing piece is provided by increasing the volume of the electrode terminal 22, the weight of the battery monomer 1 will be significantly increased, which is not conducive to the lightweight of the battery monomer 1, and the cost is high.

[0236] In some embodiments, referring to FIG. 13, before the S001 tab positioning step, the battery monomer 1 manufacturing method further comprises: S0011 electrode terminal positioning step, positioning the electrode terminal 22 in the positioning part 231, so that the positioning part 231 surrounds the outer periphery of the first connecting part 221.

[0237] Positioning the electrode terminal 22 in the positioning part 231 makes the positioning part 231 more stably surround the first connecting part 221 therein, improves the positioning stability, reduces the risk of shaking during the connection (such as welding) of the tab 32 and the first connecting part 221, and is conducive to the connection reliability.

[0238] In some embodiments, before the S001 tab positioning step, the battery monomer 1 manufacturing method further comprises: a tab pre-welding step, welding a plurality of tab pieces 32a of the tab 32 into one by ultrasonic welding to form a first welding mark; and the S002 tab connecting step comprises: directly laser welding the tab 32 pressed on the connecting surface 221a to the connecting surface 221a to form a second welding mark, and the second welding mark at least partially overlaps the first welding mark.

[0239] By first welding a plurality of tab pieces 32a of the tab 32 into one by ultrasonic welding, and then connecting the tab 32 to the electrode terminal 22 by laser welding based on the ultrasonic welding, the risk of false welding is reduced, and the connection reliability is improved.

[0240] In some embodiments, in the S002 tab connecting step, the tab 32 is welded to the connecting surface 221a while the pressing member S is kept pressing the tab 32, and the pressing member S is arranged around the welding area of the tab 32 and the connecting surface 221a.

[0241] In the S002 tab connecting step, the tab 32 is welded to the connecting surface 221a while the pressing member S is kept pressing the tab 32, and the pressing member S is arranged around the welding area of the tab 32 and the connecting surface 221a.

[0242] The above embodiments are only used to illustrate the technical solutions of the present disclosure, rather than limit the present disclosure; although the present disclosure has been described in detail with reference to the above embodiments. Those skilled in the art should understand that the technical solutions recorded in the above embodiments can still be modified, or some or all of the technical features can be replaced by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present disclosure, and they should be covered in the scope of the present disclosure. In particular, as long as there is no structural conflict, each technical feature mentioned in each embodiment can be combined in any way. The present disclosure is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the present disclosure.

Claims

1. A battery cell comprising: a case having a plurality of case walls that enclose an accommodation space, the accommodation space accommodating at least one electrode assembly including a tab, the plurality of case walls including a first case wall; an electrode terminal that penetrates the first case wall and has a first connecting portion in the accommodation space, the first connecting portion having a connecting surface on a side closer to the electrode assembly along a thickness direction of the first case wall, the connecting surface being connected to the tab; an insulating member including a positioning portion that is disposed around an outer periphery of the first connecting portion, the positioning portion having a first surface on a side closer to the electrode assembly along the thickness direction of the first case wall, the first surface being flush with at least a portion of the connecting surface near the positioning portion.

2. The battery cell according to claim 1, wherein an entire surface of the connecting surface is flush with the first surface.

3. The battery cell according to claim 1 or 2, wherein the tab is directly connected to the connecting surface.

4. The battery cell according to claim 3, wherein along a thickness direction of the tab, the tab has an overlapping portion with the connecting surface and the tab has an overlapping portion with the first surface.

5. The battery cell according to claim 3, wherein along the thickness direction of the tab, the first surface abuts the tab.

6. The battery cell according to any one of claims 1 to 5, wherein the positioning portion has a second surface that is disposed around the outer periphery of the first connecting portion and is in contact with an outer peripheral surface of the first connecting portion.

7. The battery cell according to any one of claims 1 to 6, wherein an absolute value of a height difference between the connecting surface and the first surface along the thickness direction of the first case wall is in a range of 0 mm to 0.3 mm.

8. The battery cell according to any one of claims 1 to 7, wherein a size of the first surface along a length direction and / or a width direction of the first case wall is greater than or equal to 1 mm and less than or equal to 3 mm.

9. The battery cell according to claim 3, wherein the tab is welded to the connecting surface.

10. The battery cell according to any one of claims 1 to 9, wherein the electrode terminal includes a terminal plate and a terminal disc that are connected to each other, the first connecting portion includes the terminal disc, and the terminal disc includes the connecting surface.

11. The battery cell according to any one of claims 2 to 10, wherein the electrode terminal further includes a second connecting portion on an outside of the case along the thickness direction of the first case wall, the second connecting portion is connected to the first connecting portion, and the second connecting portion includes the terminal plate.

12. The battery cell according to any one of claims 1 to 11, wherein the insulating member further includes a portion between the first connecting portion and the first case wall along the thickness direction of the first case wall.

13. The battery cell according to any one of claims 1 to 12, wherein the insulating member further includes a protruding portion that protrudes toward the side of the electrode assembly along the thickness direction of the first case wall.

14. A battery comprising: a case; the battery cell according to any one of claims 1 to 13, disposed in the case.

15. An electric device comprising the battery cell according to any one of claims 1 to 13 or the battery according to claim 14, the battery being capable of supplying electric power to the electric device.

16. An energy storage device comprising the battery cell according to any one of claims 1 to 13 or the battery according to claim 14, the battery being capable of storing and supplying electric power.

17. A battery cell manufacturing method, the battery cell including an electrode assembly, a first housing wall, an electrode terminal mounted to the first housing wall, and an insulating member, the electrode terminal having a first connecting portion, the electrode assembly including a tab, the battery cell manufacturing method comprising: a tab positioning step of pressing the tab to a connecting surface of the first connecting portion of the electrode terminal by a pressing member, the electrode terminal being positioned in a positioning portion of the insulating member, the positioning portion surrounding an outer periphery of the first connecting portion, the positioning portion having a first surface, the first surface being flush with at least a portion of the connecting surface near the positioning portion, the pressing member being supported at least partially on the first surface; a tab connecting step of directly connecting the tab pressed to the connecting surface to the connecting surface.

18. The battery cell manufacturing method according to claim 17, wherein, Before the tab positioning step, the battery cell manufacturing method further comprises: an electrode terminal positioning step of positioning the electrode terminal in the positioning portion so that the positioning portion surrounds the outer periphery of the first connecting portion.

19. The battery cell manufacturing method according to claim 17 or 18, wherein, in the tab connecting step, the tab and the connecting surface are welded while the pressing member is pressed against the tab, the pressing member surrounding a welding region of the tab and the connecting surface.

20. The battery cell manufacturing method according to any one of claims 17 to 19, wherein, Before the tab positioning step, the battery cell manufacturing method further comprises: a tab pre-welding step of pre-welding a plurality of tab pieces of the tab into one body by ultrasonic waves to form a first weld; the tab connecting step includes directly laser welding the tab pressed to the connecting surface to the connecting surface to form a second weld, the second weld at least partially overlapping the first weld.

21. The battery cell manufacturing method according to any one of claims 17 to 20, wherein, a dimension of the connecting surface along a length direction of the first housing wall is D1, a dimension of the first surface along the length direction of the first housing wall is D2, a dimension of the pressing member along the length direction of the first housing wall is D3, a dimension of the pressing member along a width direction of the first housing wall is W1, a dimension of the first surface along the width direction of the first housing wall is W2, and a dimension of the pressing member along the width direction of the first housing wall is W3, wherein D1 + 2D2 ≥ D3 and W1 + 2W2 ≥ W3.

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