Battery, battery module and electric equipment

Abstract

The utility model provides a battery, a battery module and electric equipment, and relates to the technical field of batteries. The battery comprises a shell, a cover plate, an electrode assembly, a terminal and a tab, the cover plate covers the shell to define an accommodating cavity; the electrode assembly is arranged in the accommodating cavity; the terminal is arranged on the cover plate and located on the side, away from the containing cavity, of the cover plate, and a mounting groove is formed in the side, close to the containing cavity, of the terminal and communicates with the containing cavity; the tabs are arranged in the mounting grooves and are electrically connected with the inner walls of the mounting grooves; wherein the electrode assembly extends to a notch of the mounting groove and is connected with the tab. According to the application, the tab is arranged in the terminal, so that the tab and the terminal share the height space, the space occupied by the original tab can be used for arranging the electrode assembly, and the vacant space around the position of the original tab can also be filled with the electrode assembly. Therefore, the space utilization rate of the battery can be improved.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a battery, a battery module and an electrical device. Background Art

[0002] In related technologies, a battery consists of an outer casing, external components, and internal components. The outer casing has a cavity in which the internal components are located, while the external components are mounted on the outer casing. The internal components primarily include the electrode assembly, tabs, and insulating tape. The external components primarily include terminals and explosion-proof valves. The tabs connect to the electrode assembly and, via adapters, to the terminals for current input and output.

[0003] At present, the internal space utilization rate of batteries is low, which limits the improvement of battery energy density. Utility Model Content

[0004] The embodiments of the present application provide a battery, a battery module, and an electrical device, which can improve the internal space utilization of the battery.

[0005] In the first aspect, an embodiment of the present application provides a battery, which includes a shell, a cover plate, an electrode assembly, a terminal and a tab; the cover plate is covered with the shell to define a accommodating cavity; the electrode assembly is arranged in the accommodating cavity; the terminal is arranged on the cover plate and protrudes from the side of the cover plate away from the accommodating cavity, and a mounting groove is provided on the side of the terminal close to the accommodating cavity, and the mounting groove is connected to the accommodating cavity; the tab is arranged in the mounting groove and electrically connected to the inner wall of the mounting groove; wherein the electrode assembly extends to the notch of the mounting groove and is connected to the tab.

[0006] In one embodiment, the tab has multiple layers, and the multiple layers of tabs are stacked and bent to be disposed in the mounting groove.

[0007] In one embodiment, along the stacking direction of the tabs, the multiple layers of tabs are divided into two tab groups, and the two tab groups are stacked and bent respectively to be disposed in the mounting grooves.

[0008] In one embodiment, each tab group includes a bent portion and a planar portion connected in sequence, one end of the bent portion is connected to the electrode assembly, and the other end is connected to the planar portion, and the planar portion is electrically connected to the bottom of the mounting slot; wherein the bent portions of the two tab groups are bent toward each other.

[0009] In one embodiment, the ends of the planar portions of the two tab groups are opposite to each other and spaced apart.

[0010] In one embodiment, along the arrangement direction of the two tab groups, the mounting slot has a pair of oppositely disposed first slot walls, and the opposite sides of the two tab groups are first surfaces, which are at least partially in contact with the adjacent first slot walls.

[0011] In one embodiment, a plurality of cutting openings are provided on the tabs along the width direction of the tabs, and the plurality of cutting openings on two adjacent layers of tabs correspond to each other one by one. The plurality of cutting openings separate the tab group into a plurality of spaced-apart tab units.

[0012] In one embodiment, along the thickness direction of the tab, the stacked and bent multiple layers of tabs are interference-fitted with the mounting grooves.

[0013] In one embodiment, the battery is a square-cased battery. Along the width direction of the cover, the cover has a width dimension W1, and the terminal has a width dimension W2, satisfying: 50% W1≤W2≤W1-2mm.

[0014] In one embodiment, the battery is a square-shell battery, and along the width direction of the cover plate, the groove wall of the mounting groove has a thickness dimension D that satisfies: 0.5 mm ≤ D ≤ 4 mm.

[0015] In one embodiment, along the width direction of the tab, the tab is loosely fitted in the mounting groove.

[0016] In one embodiment, along the width direction of the tab, the tab has a width dimension W4, and the mounting groove has a first dimension W5, satisfying: 50% W5≤W4≤W5-4mm, and in the width direction of the tab, the distance between the two ends of the tab and the groove wall of the adjacent mounting groove is consistent.

[0017] In one embodiment, the battery is a square-shell battery. Along the width direction of the tab, the cover has a length dimension L1, and the terminal has a second dimension L2, satisfying: 10% L1≤L2<50% L1.

[0018] In one embodiment, the terminal is a rectangular column, and its axis is perpendicular to the cover.

[0019] In one embodiment, the terminal includes a positive terminal and a negative terminal, and at least one of the positive terminal and the negative terminal is insulated and isolated from the cover plate; the tab includes a positive tab and a negative tab, and the positive tab is arranged in the mounting groove of the positive terminal, and the negative tab is arranged in the mounting groove of the negative tab terminal.

[0020] In one embodiment, the electrode assembly is insulated and fitted to the cover plate or insulated and abutted against the cover plate.

[0021] In one embodiment, the cover plate is provided with a through hole, one end of the through hole is communicated with the accommodating cavity, and part of the terminal is passed through the through hole.

[0022] In one embodiment, the cover plate is provided with a through hole, one end of the through hole is communicated with the accommodating cavity, and the terminal is provided on a side of the through hole facing away from the accommodating cavity.

[0023] In one embodiment, the battery further includes an insulating member, and the terminal is insulated and isolated from the cover plate by the insulating member.

[0024] In one embodiment, one end of the insulating member close to the accommodating cavity is flush with the surface of the cover plate facing the accommodating cavity.

[0025] In one embodiment, the cover plate and the housing are welded or integrally formed.

[0026] In one embodiment, the battery is one of the following batteries: a square-shell battery, a cylindrical battery, a prismatic battery, a special-shaped shell battery, and a button battery.

[0027] In one embodiment, at least a portion of the inner wall of the mounting groove is in contact with the tab.

[0028] In a second aspect, an embodiment of the present application provides a battery module, which includes a battery, wherein there are multiple batteries, the multiple batteries are connected in series and / or in parallel, and at least one battery is the aforementioned battery.

[0029] In a third aspect, an embodiment of the present application provides an electrical device, which includes the aforementioned battery or the aforementioned battery module, and the battery or battery module supplies power to the electrical device.

[0030] Beneficial effects of the embodiments of the present application:

[0031] In the embodiments of the present application, the tabs are positioned within the terminals, thereby allowing the tabs and the terminals to share a common height space. This allows the space originally occupied by the tabs to be used to accommodate the electrode assembly, and the vacant space around the original tab locations can also be filled with the electrode assembly. This improves the space utilization of the battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0033] Figure 1 is a schematic diagram of the internal structure of a battery provided in an embodiment of the present application;

[0034] Figure 2 yes Figure 1 Enlarged view of point A in the middle;

[0035] Figure 3 Schematic diagram of the structure of the tabs stacked and bent according to an embodiment of the present application;

[0036] Figure 4 This is another schematic diagram of a structure in which tabs are stacked and bent, as provided in an embodiment of the present application;

[0037] Figure 51 is a schematic diagram of a structure in which another tab is stacked and bent, provided in an embodiment of the present application;

[0038] Figure 6 yes Figure 4 Enlarged view of point B in the middle;

[0039] Figure 7 is a schematic diagram of the internal structure of another battery provided in an embodiment of the present application;

[0040] Figure 8 yes Figure 7 Enlarged view of point C in the middle;

[0041] Figure 9 This is a schematic diagram of the dimensions of the terminals provided in the embodiments of the present application;

[0042] Figure 10 1 is a schematic diagram of the internal structure of another battery provided in an embodiment of the present application;

[0043] Figure 11 Schematic diagram of the structure of the battery provided in the embodiment of the present application;

[0044] Figure 12 It is a structural diagram of the electrical equipment provided in the embodiment of the present application.

[0045] Description of reference numerals:

[0046] 001-battery;

[0047] 011 - housing; 111 - accommodating cavity; 012 - cover plate; 121 - through hole; 013 - electrode assembly; 014 - terminal; 141 - positive electrode terminal; 142 - negative electrode terminal; 143 - mounting groove; 1431 - first groove wall; 015 - tab; 151 - positive electrode tab; 152 - negative electrode tab; 153 - tab assembly; 1531 - bending portion; 1533 - flat portion; 1534 - first surface; 1535 - tab unit; 154 - cutting opening; 016 - insulating member;

[0048] 002-battery module; 021-installation cavity; 022-box; 023-box cover;

[0049] 003-Electrical equipment; 031-Motor; 032-Controller. DETAILED DESCRIPTION

[0050] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without making creative efforts are within the scope of protection of this application.

[0051] In addition, it should be understood that the specific embodiments described herein are only used to illustrate and explain the present application and are not intended to limit the present application. In the present application, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present application, "multiple" means two or more, unless otherwise clearly and specifically defined.

[0052] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "installed," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections, electrical connections, or mutual communication; they can refer to direct connections or indirect connections through an intermediate medium; they can refer to internal communication between two components or the interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0053] To facilitate understanding of the solution of the present application, the spline curves and arrows used in the drawings are explained here: the components indicated by the spline curves without arrows are solid components, that is, components with solid structures; the components indicated by the spline curves with arrows are virtual components, that is, components without solid structures.

[0054] Before introducing the battery, battery module and electrical equipment provided by the present application, the relevant technologies of the present application are described in detail.

[0055] In this field, batteries primarily include prismatic and cylindrical batteries. Prismatic batteries include an outer casing, an electrode assembly, tabs, and electrolyte disposed within the outer casing. The outer casing comprises a housing with an opening and a cover plate that seals the opening. The cover plate fits over the housing to define a cavity for storing the battery's internal components. The electrolyte is primarily located at the bottom of the cavity and permeates the electrode sheets through capillary action. Terminals are located on the cover plate. The electrode assembly comprises a positive electrode sheet, a separator, and a negative electrode sheet stacked in sequence, or a positive electrode sheet, a separator, and a negative electrode sheet stacked and wound in sequence. Tabs are divided into positive and negative tabs. The positive tab is connected to the positive electrode sheet and connected to the positive terminal via a positive current collector. The negative tab is connected to the negative electrode sheet and connected to the negative terminal via a negative current collector. In prismatic batteries, the tabs are primarily located on the end surface of the electrode assembly facing the cover plate. This structure leaves a large void space between the inner cavity of the outer casing and the tabs, at least along the width of the tabs. However, this vacant space is not equipped with components or filled with functional materials. Therefore, the presence of this vacant space leads to low space utilization of the battery, resulting in low energy density of the battery. The width direction of the tab is the extension direction of the connection between the tab and the pole piece.

[0056] Based on this, the embodiments of the present application provide a battery, a battery module and an electrical device for solving the problem of low space utilization of the battery, and the battery, battery module and electrical device of the present application are described in detail through the following embodiments.

[0057] See also Figure 1 , Figure 1 It is a schematic diagram of the internal structure of the battery 001 provided in an embodiment of the present application. The embodiment of the present application provides a battery 001, which includes a shell 011, a cover plate 012, an electrode assembly 013, a terminal 014 and a tab 015. The cover plate 012 covers the shell 011 to define a accommodating cavity 111. The electrode assembly 013 is arranged in the accommodating cavity 111. The terminal 014 is arranged on the cover plate 012 and protrudes from the side of the cover plate 012 away from the accommodating cavity 111. A mounting groove 143 is provided on the side of the terminal 014 close to the accommodating cavity 111. The mounting groove 143 is connected to the accommodating cavity 111. The tab 015 is arranged in the mounting groove 143 and is electrically connected to the inner wall of the mounting groove 143. Among them, the electrode assembly 013 extends to the notch of the mounting groove 143 and is connected to the tab 015, as shown Figure 2 As shown, Figure 2 yes Figure 1 Enlarged view of point A in the middle.

[0058] Furthermore, the tab 015 is welded to the terminal 014 .

[0059] Among them, the battery 001 is one of the following batteries 001: square shell battery, cylindrical battery, prismatic battery, special-shaped shell battery, button battery.

[0060] It is understood that electrode assembly 013 includes a positive electrode sheet, a separator, and a negative electrode sheet stacked in sequence, or electrode assembly 013 includes a positive electrode sheet, a separator, and a negative electrode sheet stacked and wound in sequence. The positive electrode sheet includes a current collector and a positive electrode active material layer disposed on the current collector, and the negative electrode sheet includes a current collector and a negative electrode active material layer disposed on the current collector. The tab 015 can be integrally provided as at least a portion of the current collector that is not coated with the active material layer. In other embodiments, the tab 015 can be separately welded to the current collector.

[0061] In addition, battery 001 may include a terminal 014. In this case, a tab 015 of one polarity contacts terminal 014 to transmit current of one polarity, while a tab 015 of the other polarity can directly contact cover 012 or housing 011 to transmit current of the other polarity. Furthermore, terminal 014 should be insulated from cover 012. In another embodiment, battery 001 may also include two terminals 014, namely a positive terminal 141 and a negative terminal 142. The structure of positive terminal 141 is identical to that of negative terminal 142. Positive tab 151 and negative tab 152 are located within positive terminal 141 and negative terminal 142, respectively. Furthermore, at least one of positive terminal 141 and negative terminal 142 is insulated from cover 012.

[0062] In this embodiment, the tab 015 is positioned within the terminal 014, thereby allowing the tab 015 and the terminal 014 to share a common height space. This allows the space originally occupied by the tab 015 to be used to accommodate the electrode assembly 013, and the vacant space around the original location of the tab 015 can also be filled with the electrode assembly 013. This improves the space utilization of the battery 001 and increases the size of the electrode assembly 013, thereby increasing the energy density of the battery 001.

[0063] Furthermore, the increased size of the electrode assembly 013 allows the same current to be distributed over a larger area, thereby reducing the current density per unit area or unit length, thereby lowering the electron migration resistance and, consequently, the DCR (direct current resistance) during charge and discharge of the battery 001. Furthermore, the larger electrode assembly 013 provides more active material area wetted by the electrode solution, thereby increasing the migration speed of lithium ions and reducing the DCR during charge and discharge of the battery 001.

[0064] The reduced DCR of battery 001 can reduce the temperature rise of battery 001 during the charge and discharge process. Furthermore, the increased size of electrode assembly 013 can provide a larger heat dissipation area within battery 001, improving its heat dissipation efficiency and thus reducing the temperature rise of battery 001 during the charge and discharge process.

[0065] Furthermore, by placing tab 015 inside terminal 014, the area of contact between terminal 014 and tab 015 is increased, and terminal 014 can have multiple locations facing tab 015. This allows terminal 014 to contact tab 015 at multiple locations to achieve electrical conductivity, thereby improving the reliability of the conductive connection between terminal 014 and tab 015. Furthermore, the adapter used to connect tab 015 to terminal 014 can be omitted, reducing the manufacturing cost of battery 001 and improving the manufacturing efficiency of battery 001.

[0066] Optionally, the electrode assembly 013 is insulated from the cover plate, so that the electrode assembly 013 can fill the receiving cavity 111 of the battery 001 , thereby further increasing the size of the electrode assembly 013 and improving the internal space utilization of the battery 001 .

[0067] See also Figure 3 , Figure 3 FIG1 is a schematic diagram of a structure of a tab 015 provided in an embodiment of the present application, wherein the tab 015 is stacked and bent. In one embodiment, the tab 015 has multiple layers. The multiple layers of tabs 015 are stacked and bent and disposed in the mounting groove 143.

[0068] It can be understood that after the multi-layer tabs 015 are stacked, one side can be bent and placed in the mounting groove 143, such as Figure 3 As shown, it can also be bent multiple times and set in the installation groove 143.

[0069] In this embodiment, by bending and stacking multiple layers of tabs 015 , the height of the tabs 015 can be reduced, thereby controlling the overall height of the battery 001 and improving the energy density of the battery 001 .

[0070] See also Figure 4 , Figure 4 FIG1 is a schematic diagram of another embodiment of the present application showing a stacked and bent tab 015. In one embodiment, along the stacking direction of the tabs 015, the multiple tabs 015 are divided into two tab groups 153. The two tab groups 153 are stacked and bent and disposed in the mounting slot 143.

[0071] The stacking direction is the stacking direction of the tab 015 before it is bent.

[0072] Specifically, the bending directions of the two tab groups 153 may be opposite to each other, or the bending directions of the two tab groups 153 may be the same. When the bending directions of the two tab groups 153 are opposite to each other, the two tab groups 153 may be bent toward each other, that is, the concave surfaces formed by the bending of the two tab groups 153 are opposite to each other; or the two tab groups 153 may be bent away from each other, that is, the concave surfaces formed by the bending of the two tab groups 153 are opposite to each other.

[0073] It can be understood that each tab group 153 includes a plurality of tabs 015 stacked in sequence.

[0074] In addition, the number of tabs 015 layers in the two tab groups 153 can be the same or different. Optionally, the structures of the two tab groups 153 are symmetrical to each other. In this way, the connection structure between the terminal 014 and the tab 015 can be a symmetrical structure, thereby making the force applied to the terminal 014 and the electrode assembly 013 symmetrical, thereby improving the force state of the terminal 014 and the electrode assembly 013.

[0075] In this embodiment, by dividing the multi-layer tabs 015 into two tab groups 153, the height of the tabs 015 after bending can be reduced, thereby further reducing the height occupied by the tabs 015, which is beneficial to controlling the overall height of the battery 001 and improving the energy density of the battery 001.

[0076] Among them, the two sets of tabs 015 can be bent toward each other to form Figure 4 The structure shown can also be bent back to back to form Figure 5 The structure shown, Figure 5 This is a schematic diagram of the structure of another tab 015 provided in an embodiment of the present application, which is stacked and bent.

[0077] See also Figure 6 , Figure 6 yes Figure 4 An enlarged view of point B in the figure. In one embodiment, each tab assembly 153 includes a bent portion 1531 and a planar portion 1533 connected in sequence. One end of the bent portion 1531 is connected to the electrode assembly 013, and the other end is connected to the planar portion 1533. The planar portion 1533 is electrically connected to the bottom of the mounting slot 143. The bent portions 1531 of the two tab assemblies 153 are bent toward each other.

[0078] Specifically, if Figure 4 As shown, each tab group 153 extends from one end near the electrode assembly 013 to the other end by first extending toward a wall of the mounting slot 143, that is, extending in a direction away from the other tab group 153, and then gradually bending toward the other tab group 153. In this way, the bent portions 1531 of the two tab groups 153 bend toward each other, that is, along the stacking direction of the tabs 015, the inner concave surfaces of each tab group 153 are arranged opposite each other.

[0079] Exemplarily, the side of the planar portion 1533 facing away from the electrode assembly 013 is in contact with the bottom of the mounting groove 143 to increase the contact surface between the two and improve the reliability of current transmission.

[0080] In this embodiment, the above arrangement enables the two tab groups 153 to be bent toward each other. This, on the one hand, allows each tab group 153 to have a larger surface area in contact with the inner wall of the mounting slot 143, thereby providing a larger current transmission surface between each tab group 153 and the terminal 014, thereby improving the reliability of current transmission between the tab group 153 and the terminal 014. On the other hand, to further improve the reliability of current transmission between the tab group 153 and the terminal 014, the tab group 153 needs to be compressed in a direction perpendicular to the cover plate to increase the contact force between the tab group 153 and the bottom of the mounting slot 143, as well as the contact force between the opposite sides of the tab group 153 and the pair of opposing slot walls of the mounting slot 143. In this case, by bending the two tab groups 153 toward each other, a spacing is created between the two tab groups 153, thereby reducing the compressive force between the two tab groups 153 and each other, thereby improving the stress state of the tab groups 153.

[0081] See also Figure 4 or Figure 6 In one embodiment, the ends of the planar portions 1533 of the two tab groups 153 are opposite to each other and spaced apart.

[0082] Exemplarily, the interval is between 0.5 mm and 4 mm. It is understood that the interval includes but is not limited to 0.5 mm, 0.8 mm, 1 mm, 1.2 mm, 1.5 mm, 1.8 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 3.6 mm, 3.8 mm, 3.9 mm, and 4 mm.

[0083] In this embodiment, through the above-mentioned arrangement, on the one hand, the tabs 015 can be installed in the mounting grooves 143 so that when the tab groups 153 are pressurized and the ends of the flat portions 1533 approach each other, a buffer space is provided for the two tab groups 153 to avoid interference between the two tabs 015; on the other hand, when the tabs 015 expand due to heat, a thermal expansion space is provided for the two tabs 015 to avoid interference between the two tabs 015.

[0084] See also Figure 4 or Figure 6 In one embodiment, the mounting slot 143 has a pair of opposing first slot walls 1431 along the arrangement direction of the two tab groups 153. The opposite sides of the two tab groups 153 are first surfaces 1534. The first surfaces 1534 are at least partially in contact with the adjacent first slot walls 1431.

[0085] In this embodiment, the above arrangement can increase the contact area between the tab 015 and the inner wall of the mounting groove 143 , thereby improving the reliability of the conductive connection between the tab 015 and the terminal 014 and further improving the reliability of the battery 001 .

[0086] See also Figure 7 and Figure 8 , Figure 7 This is a schematic diagram of the internal structure of another battery 001 provided in an embodiment of the present application. Figure 8 yes Figure 7 Enlarged view of point C in the middle. In one embodiment, a plurality of cutting openings 154 are provided on the tabs 015 along the width direction of the tabs 015 , and the plurality of cutting openings 154 on two adjacent layers of tabs 015 correspond one to one. The plurality of cutting openings 154 separate the tab group 153 into a plurality of spaced-apart tab 015 units.

[0087] In the embodiment, by setting the cutting opening 154, each layer of the tab 015 can be composed of multiple smaller sub-tab groups 153. In this way, the tab 015 can be prevented from folding randomly during the stacking of the pole sheets, thereby improving the processability of the tab 015 and facilitating the smooth assembly of the battery 001.

[0088] In one embodiment, along the thickness direction of the tab 015 , the stacked and bent multiple layers of tabs 015 are interference-fitted with the mounting groove 143 .

[0089] It is understood that the tab 015 is a metal layer with a thin thickness and high flexibility. Therefore, during assembly, the tab 015 is provided with an interference fit in the thickness direction, and the tab 015 can be squeezed to smoothly enter the mounting groove 143 without affecting the assembly between the tab 015 and the terminal 014.

[0090] Based on this, in this embodiment, the above configuration can increase the contact surface area and contact force between the tab 015 and the inner wall of the mounting groove 143 , thereby improving the reliability of the electrical connection between the tab 015 and the terminal 014 .

[0091] See also Figure 9 , Figure 9 This is a schematic diagram of the dimensions of terminal 014 provided in an embodiment of the present application. In one embodiment, battery 001 is a prismatic battery. Along the width direction of cover plate 012, the cover plate has a width dimension W1. Terminal 014 has a width dimension W2, satisfying the following: 50% W1 ≤ W2 ≤ W1-2 mm.

[0092] It can be understood that the maximum value of the width dimension W2 of the terminal 014 is W1-2mm, and the minimum value is 50% W1. Therefore, the width dimension W2 of the terminal 014 can be, but is not limited to, 50% W1, 52% W1, 55% W1, 58% W1, 60% W1, 62% W1, 65% W1, 66% W1, 68% W1, 70% W1, 72% W1, 75% W1, 78% W1, 80% W1, W1-8mm, W1-7mm, W1-6mm, W1-5mm, W1-4mm, W1-3.5mm, W1-3.2mm, W1-3 mm, W1-2.8mm, W1-2.6mm, W1-2.5mm, and W1-2mm.

[0093] In addition, the cover 012 is a plate-like structure, and its thickness dimension in the axial direction of the terminal 014 is a length dimension. In the plane perpendicular to the axial direction of the terminal 014, the longer side is the long side, the shorter side is the width side, and the straight line where the short side is located is the width direction of the cover 012.

[0094] In this embodiment, through the above configuration, on the one hand, the terminal 014 can be prevented from being too small, thereby improving the reliability of the connection between the terminal 014 and the busbar; on the other hand, the terminal 014 can be prevented from being too large to affect the connection between it and the end cover.

[0095] In another embodiment, when the terminal 014 and the cover plate 012 are integrally formed, the maximum value of the width dimension W2 of the terminal 014 may be consistent with the width dimension W1 of the cover plate.

[0096] See also Figure 9 In one embodiment, the battery 001 is a square shell battery. Along the width direction of the cover plate 012, the groove wall of the mounting groove 143 has a thickness dimension D, which satisfies: 0.5mm≤D≤4mm.

[0097] It can be understood that the thickness dimension D of the portion of the terminal 014 opposite to the mounting groove 143 includes but is not limited to 0.5mm, 0.8mm, 1mm, 1.2mm, 1.5mm, 1.8mm, 2mm, 2.2mm, 2.5mm, 2.8mm, 3mm, 3.2mm, 3.5mm, 3.6mm, 3.8mm, and 4mm.

[0098] In this embodiment, through the above-mentioned limitation, on the one hand, it is possible to avoid the thickness of this part being too small, which would result in lower strength of the terminal 014, so that the strength of the terminal 014 can meet the use requirements; on the other hand, it is possible to avoid the thickness of this part being too large, which would result in unnecessary increase in material, so that the material cost of the terminal 014 can be controlled.

[0099] In one embodiment, along the width direction of the tab 015 , the tab 015 is loosely fitted with the mounting groove 143 .

[0100] The width direction of the tab 015 is the extension direction of the connection portion 1531 between the tab 015 and the electrode piece.

[0101] It is understood that the tab 015 cannot be compressed in its width direction due to its connection to the electrode sheet. Therefore, the tab 015 and the mounting slot 143 are configured to have a clearance fit in the width direction of the tab, thereby improving the smoothness of the tab 015 entering the mounting slot 143 and thus enhancing assembly convenience.

[0102] See also Figure 2 In one embodiment, along the width direction of the tab 015 , the tab 015 has a width dimension W4, and the mounting groove 143 has a first dimension W5, satisfying: 50% W5≤W4≤W5-4mm, and in the width direction of the tab 015 , the distance between the two ends of the tab 015 and the groove wall of the adjacent mounting groove 143 is consistent.

[0103] It can be understood that the width dimension W5 of the tab 015 is 4mm, and the minimum value is 50% W5. Therefore, the width dimension W4 of the terminal can be, but is not limited to, 50% W5, 52% W5, 55% W5, 58% W5, 60% W5, 62% W5, 65% W5, 66% W5, 68% W5, 70% W5, 72% W5, 75% W5, 78% W5, 80% W5, W5-8mm, W5-7.5mm, W5-7mm, W5-6.5mm, W5-6mm, W5-5.8mm, W5-5.5mm, W5-5mm, W5-4.8mm, W5-4.5mm, W5-4.2mm, and W5-4mm.

[0104] In this embodiment, through the above-mentioned setting, the tab 015 and the mounting groove 143 can have an appropriate fitting gap in the width direction of the tab 015, which can not only ensure the smooth assembly of the tab 015 to the mounting groove 143, but also make the tab 015 have an appropriate area to ensure the current collecting capacity.

[0105] See also Figure 1 In one embodiment, the battery 001 is a square-shell battery, and the cover has a length dimension L1 along the width direction of the tab 015. The terminal 014 has a second dimension L2, which satisfies: 10% L1≤L2<50% L1.

[0106] It can be understood that when the battery 001 includes two terminals 014 and the second dimensions of the two terminals 014 are relatively large, an insulating plate may be provided between the two terminals 014 to improve insulation between the two terminals 014 .

[0107] Exemplarily, the second size L2 of terminal 014 includes but is not limited to 10% L1, 12% L1, 14% L1, 15% L1, 16% L1, 18% L1, 20% L1, 22% L1, 25% L1, 28% L1, 30% L1, 33% L1, 35% L1, 36% L1, 40% L1, 42% L1, 44% L1, 45% L1, 46% L1, 47% L1, 48% L1, and 49% L1.

[0108] Further, 10% L1≤L2≤45% L1. Optionally, 30% L1≤L2≤40% L1.

[0109] In this embodiment, through the above definition, on the one hand, it can avoid the terminal 014 being too small, thereby improving the reliability of the connection between the terminal 014 and the busbar; on the other hand, it can avoid the terminal 014 being too large to affect the layout of other components.

[0110] In one embodiment, the terminal 014 is a rectangular column, and its axis is perpendicular to the cover.

[0111] Compared with terminals 014 of other shapes, in this embodiment, through the above-mentioned arrangement, the installation groove 143 can have a larger size under the premise of a certain volume of the terminal 014, so as to accommodate more tabs 015, thereby increasing the area of the tab 015 and improving the current collecting capacity.

[0112] In addition, by increasing the area of the tab 015 , the DCR of the battery 001 can be reduced and the temperature rise inside the battery 001 can be controlled.

[0113] See also Figure 1 or Figure 10 , Figure 10 This is a schematic diagram of the internal structure of another battery 001 provided in an embodiment of the present application. In one embodiment, terminal 014 includes a positive terminal 141 and a negative terminal 142. At least one of positive terminal 141 and negative terminal 142 is insulated from the cover plate. Tab 015 includes a positive tab 151 and a negative tab 152. Positive tab 151 is mounted in mounting slot 143 of positive terminal 141, while negative tab 152 is mounted in mounting slot 143 of terminal 014.

[0114] It can be understood that one of the positive terminal 141 and the negative terminal 142 is insulated from the cover plate, such as Figure 10 As shown, one of the terminals 014 is insulated from the cover plate 012 by an insulating member 016 , and the other terminal 014 can be welded to the cover plate 012 or can be integrally formed with the cover plate 012 .

[0115] Alternatively, the positive terminal 141 and the negative terminal 142 are both insulated and isolated from the cover plate, such as Figure 1 As shown, the two terminals 014 are insulated and isolated from the cover plate 012 by two insulating members 016 .

[0116] Compared to the battery 001 with only one terminal 014 , the present embodiment has two terminals 014 , which can enhance the symmetry of the battery 001 , thereby making the force applied to the battery 001 more symmetrical and further improving the force state of the battery 001 .

[0117] See Figure 2 In one embodiment, the electrode assembly 013 and the cover plate 012 are insulated and fitted or insulated and abutted.

[0118] Among them, the insulating contact between the electrode assembly 013 and the cover plate 012 can be that an insulating layer that does not react with the electrolyte is coated on the surface where the cover plate 012 and the electrode assembly 013 contact, an insulating pad is provided on the surface where the cover plate 012 and the electrode assembly 013 contact, or an insulating film is coated on the surface of the electrode assembly 013.

[0119] In this embodiment, through the above arrangement, the electrode assembly 013 can fill the accommodating cavity 111 , thereby making the electrode assembly 013 have a larger size, thereby improving the energy density of the battery 001 .

[0120] See Figure 2 In one embodiment, the cover plate 012 is provided with a through hole 121 . One end of the through hole 121 is in communication with the accommodating cavity 111 . Part of the terminal 014 is passed through the through hole 121 .

[0121] The end of the terminal 014 close to the electrode assembly 013 may be located in the through hole 121 , or may be flush with the end of the through hole 121 close to the electrode assembly 013 .

[0122] In addition, the terminal 014 includes a positive terminal 141 and a negative terminal 142 , wherein at least one terminal 014 is insulated from the cap plate 012 .

[0123] In this embodiment, the above arrangement can increase the mating surface between the terminal 014 and the cover plate 012 , thereby increasing the mating stability between the terminal 014 and the cover plate 012 , and further improving the structural reliability of the battery 001 .

[0124] In another embodiment, the cover plate 012 is provided with a through hole 121. One end of the through hole 121 communicates with the accommodating cavity 111, and the terminal 014 is disposed on the side of the through hole facing away from the accommodating cavity 111. Specifically, the terminal 014 can be directly welded to the surface of the cover plate 012 facing away from the accommodating cavity 111, or a boss can be provided on the surface of the cover plate 012 facing away from the accommodating cavity 111, and the boss can be inserted into the mounting groove 143. This can reduce the welding stress on the through hole during the welding process, thereby protecting the weak portion of the cover plate 012 surrounding the through hole and improving the strength of the cover plate 012.

[0125] See also Figure 2 In one embodiment, battery 001 further includes an insulating member 016, which insulates terminal 014 from cover plate 012. Specifically, insulating member 016 is an annular structure that extends circumferentially around the through-hole. The end of insulating member 016 proximal to accommodating cavity 111 is flush with the surface of cover plate 012 proximal to accommodating cavity 111. This prevents insulating member 016 from occupying accommodating cavity 111, thereby increasing the space available for electrode assembly 013 and improving the energy density of battery 001.

[0126] In one embodiment, the cover plate 012 is welded or integrally formed with the housing 011. When welded, the cover plate 012 is positioned within the opening of the housing 011, and the surface of the cover plate 012 facing away from the accommodating cavity 111 is flush with the end of the molded opening of the housing 011. Furthermore, the integral molding process may be casting.

[0127] See also Figure 4 or Figure 5 In one embodiment, the inner wall of the mounting groove 143 is at least partially in contact with the tab 015. This allows for a larger contact surface between the mounting groove 143 and the tab 015, thereby improving the reliability of electrical transmission between the tab and the inner wall of the mounting groove 143.

[0128] See also Figure 11 , Figure 11 It is a structural diagram of a battery module 002 provided in an embodiment of the present application. An embodiment of the present application provides a battery module 002, which includes a battery. There are multiple batteries, and the multiple batteries are connected in series and / or in parallel, and at least one battery is the aforementioned battery 001.

[0129] Among them, multiple batteries can be connected in series, multiple batteries can be connected in parallel, or some of the multiple batteries can be connected in series and some can be connected in parallel.

[0130] It is understood that the battery module 002 may further include a battery box having an installation cavity 021. Multiple batteries 001 are disposed in the installation cavity 021. The box body 022 and the box cover 023 are covered with the box body 022 to define the installation cavity 021.

[0131] In another embodiment, the battery module 002 includes two end plates and a cable tie. Multiple batteries 001 are stacked sequentially between the two end plates. The cable tie binds the end plates and batteries 001 together into a single unit.

[0132] In this embodiment, by adopting the aforementioned battery 001 , the space utilization rate of the battery module 002 can be higher, and the energy density of the battery module 002 can be improved.

[0133] See also Figure 12 , Figure 12 003 is a schematic diagram of the structure of an electric device 003 provided in an embodiment of the present application. The embodiment of the present application provides an electric device 003, which includes the aforementioned battery 001 or battery module 002, and the battery 001 or battery module 002 supplies power to the electric device 003.

[0134] It is understood that the electrical equipment 003 includes, but is not limited to, electric toys, electric tools, battery-powered vehicles, cars, ships, spacecraft, and the like. Electric toys may include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys. Spacecraft may include airplanes, rockets, space shuttles, and spacecraft. Cars may include gasoline-powered cars, gas-powered cars, and new energy vehicles.

[0135] In addition, when the electric device 003 is a car, it may also include a motor 031 and a controller. The motor 031 can charge the battery module 002, or the battery module 002 can drive the motor 031. At the same time, the battery module 002 provides power to the controller.

[0136] In this embodiment, by using the aforementioned battery 001 or battery module 002 , the electric device 003 can have a battery with higher energy density when using batteries of the same volume, thereby improving the battery life of the electric device 003 .

[0137] The technical solutions and technical effects of the present application are described in detail below through specific embodiments. The following embodiments are only some embodiments of the present application and do not specifically limit the present application.

[0138] This embodiment aims to investigate the effect of changes in the location of the tab 015 on the performance of the battery 001 .

[0139] The test contents of the embodiment are described as follows:

[0140] 1. Test related instructions

[0141] The following test method is a DCR test, that is, a Direct Current Resistance test.

[0142] The equipment used for the test is a Chroma lithium-ion battery test system, model: 17040E.

[0143] The test environment temperature is: 25±2℃.

[0144] The main operation process of the test is as follows:

[0145] First, take 1C=55A as the nominal capacity, 1 / 3C, i.e. 18.3Ah as the standard charge and discharge capacity, and the average value of the actual capacitance measured after 3 weeks of charge and discharge cycles as the calibration capacity C0, where:

[0146] C0=(∑I n *T n +∑I' n *T' n ) / 6,

[0147] In this formula: n is a natural number, and n∈(1,3);

[0148] I n is the nth charging current;

[0149] T n is the nth charging time;

[0150] I' n is the nth discharge current;

[0151] T' n is the nth discharge time.

[0152] Then charge battery 001 to 4.25V at a constant current and constant voltage of 1 / 3C, with a cut-off current of 0.05C; then adjust the state of charge of battery 001 to 50% SOC at a discharge current of 1 / 3C0, and let battery 001 stand for 1 hour.

[0153] Next, when the state of charge of battery 001 is 50% SOC, discharge it at a constant current of 5C0 for 10s, and record the voltage change difference δU of battery 001 before and after discharge. 放电 And the discharge current value I 放电 , and according to the formula: DCR 放电 =δU 放电 / I 放电 , the battery charging DCR is obtained when the state of charge of battery 001 is 50% SOC;

[0154] At the same time, when the state of charge of battery 001 is 50% SOC, it is charged at a constant current of 5C0 for 10s, and the voltage change difference before and after charging is recorded. 充电 and charging current value I 充电 ; and according to the formula: DCR 充电 =δU 充电 / I 充电 , the battery discharge DCR is obtained when the state of charge of battery 001 is 50% SOC.

[0155] 2. Test Results

[0156] The test targets square-cased batteries measuring 148mm long, 91mm wide, and 26.5mm thick. The main difference between the test objects lies in whether the tab 015 is located within the terminal 014. The test targets the temperature at the center of the electrode assembly 013 of the battery 001 and the charge and discharge dynamic response (DCR) of the battery 001.

[0157] 2.1 Setting up a control group

[0158] The control group is a battery with the tabs located outside the terminals in the related art. The test data is as follows:

[0159]

[0160] Table 1. Structure and verification results of control group 1

[0161] According to Table 1, the relevant data of battery 001 with lug 015 located outside terminal 014, length 148mm*width 91mm*thickness 26.5mm are as follows:

[0162] (1) Battery capacity is 55Ah;

[0163] (2) The energy density of battery 001 is 280Wh / kg;

[0164] (3) When the state of charge of battery 001 is 50% SOC, the battery charging DCR is 0.34±0.05mΩ and the battery discharging DCR is 0.31±0.05;

[0165] (4) With a charge and discharge current of 5C=280A, after 15 minutes of operation, the temperature rise at the center of the electrode assembly 013 of the battery 001 is 17°C.

[0166] 2.2 On the premise that the external dimensions of the battery 001 are the same, the positive electrode tab 151 is set in the mounting groove 143 of the positive terminal 141, the negative electrode tab 152 is set in the mounting groove 143 of the negative terminal 142, and the electrode assembly 013 is extended to the notch of the mounting groove 143, so that the positive electrode sheet is connected to the positive electrode tab 151 and the negative electrode sheet is connected to the negative electrode tab 152.

[0167] Based on the battery 001 with the above structure, the test data obtained are as follows:

[0168]

[0169] Table 2. Structure and verification results of Example 1

[0170] According to Table 2, the relevant data of a battery with tab 015 located inside terminal 014 and a length of 148mm, a width of 91mm, and a thickness of 26.5mm are as follows:

[0171] (1) Battery capacity is 59Ah;

[0172] (2) The energy density of battery 001 is 300Wh / kg;

[0173] (3) When the state of charge of battery 001 is 50% SOC, the battery charging DCR is 0.22±0.05mΩ and the battery discharging DCR is 0.27±0.05;

[0174] (4) With a charge and discharge current of 5C=280A, after 15 minutes of operation, the temperature rise at the center of the electrode assembly 013 of the battery 001 is 9°C.

[0175] Comparing Example 1 with Control Group 1, it can be seen that when the tab 015 is located inside the terminal 014 and the electrode assembly 013 is extended to the notch of the mounting groove 143 and connected to the tab 015, the following changes can be obtained:

[0176] (1) The battery capacity increased from 55Ah to 59Ah;

[0177] (2) The energy density of battery 001 increases from 280Wh / kg to 300Wh / kg;

[0178] (3) When the state of charge of battery 001 is 50% SOC, the battery charging DCR decreases from 0.34±0.05mΩ to 0.22±0.05mΩ, and the battery discharging DCR decreases from 0.31±0.05 to 0.27±0.05;

[0179] (4) With a charge and discharge current of 5C=280A, after 15 minutes of operation, the temperature rise at the center of the electrode assembly 013 of the battery 001 dropped from 17°C to 9°C.

[0180] From the above, it can be seen that, under the premise that the external dimensions of the battery 001 remain unchanged, the tab 015 is set inside the terminal 014, the electrode assembly 013 extends to the notch of the mounting groove 143, and is connected to the tab 015. This can increase the battery capacity and energy density of the battery 001, reduce the battery charge and discharge DCR, and reduce the temperature rise inside the battery 001.

[0181] The above is a detailed introduction to the embodiments of the present application. Specific examples are used herein to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method and core idea of the present application. At the same time, for those skilled in the art, based on the ideas of the present application, there may be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A battery, characterized in that: include: case; a cover plate, covering the shell to define a receiving cavity; an electrode assembly, disposed in the accommodating cavity; The terminal is provided on the cover plate and protrudes from a side of the cover plate away from the accommodating cavity. A mounting groove is provided on a side of the terminal close to the accommodating cavity, and the mounting groove is communicated with the accommodating cavity. a tab, disposed in the mounting groove and electrically connected to an inner wall of the mounting groove; Wherein, the electrode assembly extends to the notch of the mounting groove and is connected to the electrode tab.

2. The battery according to claim 1, characterized in that The tabs have multiple layers, and the multiple layers of tabs are stacked and bent to be arranged in the mounting grooves.

3. The battery according to claim 2, characterized in that Along the stacking direction of the tabs, the multiple layers of tabs are divided into two tab groups, and the two tab groups are stacked and bent respectively and arranged in the mounting grooves.

4. The battery according to claim 3, characterized in that Each of the tab groups includes a bent portion and a flat portion connected in sequence, one end of the bent portion is connected to the electrode assembly, and the other end is connected to the flat portion, and the flat portion is electrically connected to the bottom of the mounting slot; Wherein, the bending portions of the two tab groups are bent toward each other.

5. The battery according to claim 4, characterized in that The ends of the planar portions of the two tab groups are opposite to each other and spaced apart.

6. The battery according to claim 4 or 5, characterized in that Along the arrangement direction of the two tab groups, the mounting slot has a pair of oppositely arranged first slot walls, and the opposite sides of the two tab groups are first surfaces, which are at least partially in contact with the adjacent first slot walls.

7. The battery according to any one of claims 3 to 5, characterized in that: Along the width direction of the tab, a plurality of cutting openings are provided on the tab, and the plurality of cutting openings on the tabs of two adjacent layers correspond to each other. The plurality of cutting openings separate the tab group into a plurality of tab units arranged at intervals.

8. The battery according to any one of claims 2 to 5, characterized in that: Along the thickness direction of the tab, the stacked and bent multiple layers of tabs are interference-fitted with the mounting grooves.

9. The battery according to any one of claims 1 to 5, characterized in that: The battery is a square-shell battery. Along the width direction of the cover plate, the cover plate has a width dimension W1, and the terminal has a width dimension W2, satisfying: 50% W1≤W2≤W1-2mm.

10. The battery according to any one of claims 1 to 5, characterized in that: The battery is a square-shell battery. Along the width direction of the cover plate, the groove wall of the mounting groove has a thickness dimension D that satisfies: 0.5 mm ≤ D ≤ 4 mm.

11. The battery according to any one of claims 1 to 5, characterized in that: Along the width direction of the tab, the tab is loosely fitted in the mounting groove.

12. The battery according to claim 11, characterized in that Along the width direction of the tab, the tab has a width dimension W4, and the mounting groove has a first dimension W5, satisfying: 50% W5≤W4≤W5-4mm, and in the width direction of the tab, the distance between the two ends of the tab and the adjacent groove wall of the mounting groove is consistent.

13. The battery according to any one of claims 1 to 5, characterized in that: The battery is a square-shell battery. Along the width direction of the tab, the cover plate has a length dimension L1, and the terminal has a second dimension L2, satisfying: 10% L1≤L2<50% L1.

14. The battery according to any one of claims 1 to 5, characterized in that: The terminal is a rectangular column, and its axis is perpendicular to the cover plate.

15. The battery according to any one of claims 1 to 5, characterized in that: The terminal includes a positive terminal and a negative terminal, and at least one of the positive terminal and the negative terminal is insulated and isolated from the cover plate; the tab includes a positive tab and a negative tab, and the positive tab is arranged in the mounting groove of the positive terminal, and the negative tab is arranged in the mounting groove of the negative tab terminal.

16. The battery according to any one of claims 1 to 5, characterized in that: The electrode assembly is insulated and fitted to or insulated and abutted against the cover plate.

17. The battery according to any one of claims 1 to 5, characterized in that: The cover plate is provided with a through hole, one end of the through hole is communicated with the accommodating cavity, and part of the terminal is passed through the through hole.

18. The battery according to any one of claims 1 to 5, characterized in that: The cover plate is provided with a through hole, one end of the through hole is communicated with the accommodating cavity, and the terminal is provided on a side of the through hole away from the accommodating cavity.

19. The battery according to any one of claims 1 to 5, characterized in that: The battery further includes an insulating member, and the terminal is insulated and isolated from the cover plate by the insulating member.

20. The battery according to claim 19, characterized in that One end of the insulating member close to the accommodating cavity is flush with a surface of the cover plate facing the accommodating cavity.

21. The battery according to any one of claims 1 to 5, characterized in that The cover plate is welded to or integrally formed with the shell.

22. The battery according to any one of claims 1 to 5, characterized in that At least a portion of the inner wall of the mounting groove is in contact with the tab.

23. The battery according to any one of claims 1 to 5, characterized in that The battery is one of the following batteries: square shell battery, cylindrical battery, prismatic battery, special-shaped shell battery, button battery.

24. A battery module, characterized in that: include: A battery, wherein there are multiple batteries, the multiple batteries are connected in series and / or in parallel, and at least one of the batteries is a battery according to any one of claims 1 to 23.

25. An electrical device, characterized in that: It comprises the battery according to any one of claims 1 to 23, or the battery module according to claim 24, and the battery or battery module supplies power to the electrical device.

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