Battery, battery module, and electric apparatus

Abstract

Provided in the present application are a battery, a battery module, and an electric apparatus. The battery comprises a case, a cover plate, an electrode assembly, terminals and tabs, wherein the cover plate covers the housing to define an accommodating cavity; the electrode assembly is arranged in the accommodating cavity; the terminals are arranged on the cover plate and are located on the side of the cover plate facing away from the accommodating cavity, and the terminals are each provided with a mounting groove in communication with the accommodating cavity; the tabs are arranged in mounting grooves and are electrically connected to inner walls of the mounting grooves; and the electrode assembly extends to openings of the mounting grooves and is connected to the tabs.

Description

Battery, battery module and electric device

[0001] The present application claims priority to the Chinese patent application No. 202410820196.2, filed on June 24, 2024, to the Chinese Patent Office, the whole content of the above application being incorporated herein by reference. TECHNICAL FIELD

[0002] The present application relates to the technical field of battery, in particular to a battery, a battery module and an electric device. BACKGROUND

[0003] In the related art, the battery includes a shell, an external component and an internal component. The shell has a receiving cavity, the internal component is arranged in the receiving cavity, and the external component is arranged on the shell. The internal component mainly includes an electrode assembly, a tab and an insulating paper. The external component mainly includes a terminal and an explosion-proof valve. The tab is connected with the electrode assembly and connected with the terminal through an adapter to transmit the output and input of the current. SUMMARY

[0004] In the related art, the internal space utilization rate of the battery is low, which limits the improvement of the energy density of the battery.

[0005] In a first aspect, 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 receiving cavity. The electrode assembly is arranged in the receiving cavity. The terminal is arranged on the cover plate and protrudes from the side of the cover plate away from the receiving cavity. The side of the terminal close to the receiving cavity is provided with a mounting groove, and the mounting groove is in communication with the receiving cavity. The tab is arranged in the mounting groove and electrically connected with the inner wall of the mounting groove. The electrode assembly extends to the slot opening of the mounting groove and is connected with the tab.

[0006] In a second aspect, the present application provides a battery module, which includes a plurality of batteries. The plurality of batteries are connected in series and / or in parallel. At least one battery is the battery as described above.

[0007] In a third aspect, the present application provides an electric device, which includes the battery as described above, and the battery supplies power to the electric device. Alternatively, the electric device includes the battery module as described above, and the battery module supplies power to the electric device. ADVANTAGEOUS EFFECTS

[0008] In the present application, the tab is arranged in the terminal, so that the tab and the terminal share the height space, so as to use the space originally occupied by the tab to arrange the electrode assembly, and the idle space around the original position of the tab can also be filled with the electrode assembly. In this way, the space utilization rate of the battery can be improved. BRIEF DESCRIPTION OF DRAWINGS

[0009] FIG. 1 is a schematic view of an internal structure of a battery according to an embodiment of the present application;

[0010] FIG. 2 is an enlarged view of A in FIG. 1;

[0011] FIG. 3 is a schematic view of a structure in which tabs are stacked and bent according to an embodiment of the present application;

[0012] FIG. 4 is a schematic view of another structure in which tabs are stacked and bent according to an embodiment of the present application;

[0013] FIG. 5 is a schematic view of still another structure in which tabs are stacked and bent according to an embodiment of the present application;

[0014] FIG. 6 is an enlarged view of B in FIG. 4;

[0015] FIG. 7 is a schematic view of an internal structure of a battery according to an embodiment of the present application;

[0016] FIG. 8 is an enlarged view of C in FIG. 7;

[0017] FIG. 9 is a schematic view of dimensioning at a terminal according to an embodiment of the present application;

[0018] FIG. 10 is a schematic view of an internal structure of a battery according to an embodiment of the present application;

[0019] FIG. 11 is a schematic view of a structure of a battery according to an embodiment of the present application;

[0020] FIG. 12 is a schematic view of a structure of an electric device according to an embodiment of the present application.

[0021] Explanation of Reference Numerals:

[0022] 001 - battery;

[0023] 011 - case; 111 - accommodation cavity; 012 - cover plate; 121 - through hole; 013 - electrode assembly; 014 - terminal; 141 - positive terminal; 142 - negative terminal; 143 - mounting groove; 1431 - first groove wall; 1432 - inner wall; 1433 - notch; 015 - tab; 151 - positive tab; 152 - negative tab; 153 - tab group; 1531 - bent portion; 1533 - flat portion; 1534 - first surface; 1535 - tab unit; 1536 - end portion; 154 - cut portion; 016 - insulating member;

[0024] 002 - battery module; 021 - mounting cavity; 022 - box; 023 - box cover;

[0025] 003 - electric device; 031 - motor; 032 - controller. Embodiments of the present application

[0026] Before introducing the battery, battery module and electric equipment provided in the present application, the related technologies of the present application are described in detail.

[0027] In the field, the battery mainly includes square cell and cylindrical cell. Among them, the square cell includes a shell and an electrode assembly, a tab and an electrolyte arranged in the shell. The shell includes a shell body with an opening and a cover plate closing the opening of the shell body, and the cover plate is covered on the shell body to define a receiving cavity for storing the internal components of the battery. The electrolyte is mainly located at the bottom of the receiving cavity and is infiltrated into the pole piece through capillary action. The terminal is arranged on the cover plate. The electrode assembly includes a positive pole piece, a separator and a negative pole piece stacked in sequence, or the electrode assembly includes a positive pole piece, a separator and a negative pole piece stacked and wound in sequence. The tab is divided into a positive tab and a negative tab, the positive tab is connected with the positive pole piece and connected with the positive terminal through the positive current collector, and the negative tab is connected with the negative pole piece and connected with the negative terminal through the negative current collector. In the square cell, the tab is mainly arranged on the end face of the electrode assembly facing the cover plate. In this structure, there is a large empty space between the inner cavity wall of the shell and the tab at least in the width direction of the tab. And the empty space is not provided with components or filled with functional substances. Therefore, the existence of the empty space leads to low space utilization of the battery, thereby leading to low energy density of the battery. Among them, the width direction of the tab is the extension direction of the connection part between the tab and the pole piece.

[0028] Based on this, the embodiments of the present application provide a battery, a battery module and an electric equipment for solving the problem of low space utilization of the battery. The battery, the battery module and the electric equipment provided in the embodiments of the present application are described in detail by the following embodiments and in combination with FIG. 1 to FIG. 12.

[0029] Please refer to FIG. 1, which is a schematic diagram of the internal structure of the battery 001 provided in the embodiments of the present application. The embodiments of the present application provide 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 is covered with the shell 011 to define a receiving cavity 111. The electrode assembly 013 is arranged in the receiving 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 receiving cavity 111. The side of the terminal 014 close to the receiving cavity 111 is provided with a mounting groove 143. The mounting groove 143 is in communication with the receiving cavity 111. The tab 015 is arranged in the mounting groove 143 and is electrically connected with the inner wall 1432 of the mounting groove 143. Among them, the electrode assembly 013 extends to the slot opening 1433 of the mounting groove 143 and is connected with the tab 015, as shown in FIG. 2, which is an enlarged view of A in FIG. 1.

[0030] Specifically, the tab 015 is welded with the terminal 014.

[0031] The battery 001 is one of a square cell, a cylindrical cell, a prismatic cell, a special-shaped cell, and a button cell.

[0032] It can be understood that the electrode assembly 013 comprises a positive electrode sheet, a separator, and a negative electrode sheet stacked in sequence, or the electrode assembly 013 comprises a positive electrode sheet, a separator, and a negative electrode sheet stacked in sequence and wound. The positive electrode sheet comprises a current collector and a positive active material layer disposed on the current collector, and the negative electrode sheet comprises a current collector and a negative active material layer disposed on the current collector. The tab 015 can be integrally provided as at least a part of an area of the current collector without the active material layer. In other embodiments, the tab 015 can be separately welded to the current collector.

[0033] In addition, the battery 001 can comprise one terminal 014. At this time, the tab 015 of one polarity is in contact with the terminal 014 to achieve current transmission of one polarity, and the tab 015 of the other polarity can be directly in contact with the cover plate 012 or the shell 011 to achieve current transmission of the other polarity. Moreover, the terminal 014 should be insulated and isolated from the cover plate 012. In another embodiment, the battery 001 can also comprise two terminals 014, which are a positive terminal 141 and a negative terminal 142. The positive terminal 141 has the same structure as the negative terminal 142. The positive tab 151 and the negative tab 152 are located in the positive terminal 141 and the negative terminal 142, respectively. Moreover, at least one of the positive terminal 141 and the negative terminal 142 is insulated and isolated from the cover plate 012.

[0034] In the present embodiment, by arranging the tab 015 in the terminal 014, the tab 015 and the terminal 014 share the same height space, so that the space originally occupied by the tab 015 can be used to arrange the electrode assembly 013, and the idle space around the original position of the tab 015 can also be filled by the electrode assembly 013. In this way, on the one hand, the space utilization of the battery 001 can be improved, and on the other hand, the size of the electrode assembly 013 can be increased, thereby improving the energy density of the battery 001.

[0035] Moreover, based on the increase in the size of the electrode assembly 013, the same size of current can be distributed on a larger area, thereby reducing the current density per unit area or per unit length, reducing the migration resistance of electrons, and thereby reducing the DCR (direct current resistance) of the battery 001 during charging and discharging. Moreover, the larger electrode assembly 013 can provide more active material regions that are soaked by the electrolyte, thereby helping to improve the migration speed of lithium ions, thereby reducing the DCR of the battery 001 during charging and discharging.

[0036] The DCR of the battery 001 can be reduced based on the reduced size of the electrode assembly 013, and the electrode assembly 013 inside the battery 001 can have a larger heat dissipation area based on the increased size of the electrode assembly 013, which can help improve the heat dissipation efficiency of the electrode assembly 013, thereby reducing the temperature rise of the battery 001 during charging and discharging.

[0037] In addition, the tab 015 is arranged inside the terminal 014, so that the relative area of the terminal 014 and the tab 015 can be increased, and the terminal 014 can have multiple parts in contact with the tab 015 for electrical conduction. In this way, the terminal 014 can be in contact with the tab 015 through multiple parts for electrical conduction, which can improve the reliability of the electrical connection between the terminal 014 and the tab 015, and can omit the adapter for connecting the tab 015 and the terminal 014, which can reduce the manufacturing cost of the battery 001 and improve the manufacturing efficiency of the battery 001.

[0038] Optionally, the electrode assembly 013 is in insulating contact with the cover plate. In this way, the electrode assembly 013 can fill the accommodation cavity 111 of the battery 001, so as to increase the size of the electrode assembly 013 and improve the space utilization inside the battery 001.

[0039] Referring to FIG. 3, FIG. 3 is a schematic structural diagram of the tab 015 in a stacked and bent structure according to an embodiment of the present application. In an embodiment, the tab 015 has multiple layers. The multiple layers of the tab 015 are stacked and bent and arranged in the mounting groove 143.

[0040] It can be understood that after the multiple layers of the tab 015 are stacked, one side of the tab 015 can be bent and arranged in the mounting groove 143, as shown in FIG. 3, or the tab 015 can be bent multiple times and arranged in the mounting groove 143.

[0041] In the embodiment, by arranging the multiple layers of the tab 015 to be bent and stacked, the height occupied by the tab 015 can be reduced, so as to control the overall height of the battery 001, which can help improve the energy density of the battery 001.

[0042] Referring to FIG. 4, FIG. 4 is another schematic structural diagram of the tab 015 in a stacked and bent structure according to an embodiment of the present application. In an embodiment, along the stacking direction of the tab 015, the multiple layers of the tab 015 are divided into two tab groups 153. The two tab groups 153 are stacked and bent and arranged in the mounting groove 143.

[0043] The stacking direction is the direction of the tab 015 before being bent.

[0044] Specifically, the bending directions of the two groups of tabs 153 can be opposite to each other, or the bending directions of the two groups of tabs 153 can be consistent. When the bending directions of the two groups of tabs 153 are opposite to each other, the two groups of tabs 153 can be bent towards each other, that is, the concave surfaces formed by the bending of the two groups of tabs 153 are opposite to each other; or the two groups of tabs 153 can be bent away from each other, that is, the concave surfaces formed by the bending of the two groups of tabs 153 are away from each other.

[0045] It can be understood that each group of tabs 153 includes a plurality of tabs 015 stacked in sequence.

[0046] In addition, the number of layers of the tabs 015 of the two groups of tabs 153 can be the same or different. Alternatively, the structures of the two groups of tabs 153 are symmetrical to each other, so that the connection structure between the terminal 014 and the tab 015 is a symmetrical structure, thereby making the force on the terminal 014 and the electrode assembly 013 symmetrical, so as to improve the stress state of the terminal 014 and the electrode assembly 013.

[0047] In the embodiment, by dividing the plurality of layers of tabs 015 into two groups of tabs 153, the height dimension of the tab 015 after bending can be reduced, thereby reducing the height occupied by the tab 015, facilitating control of the overall height dimension of the battery 001, and improving the energy density of the battery 001.

[0048] The two groups of tabs 015 can be bent towards each other to form the structure shown in FIG. 4, or can be bent away from each other to form the structure shown in FIG. 5, which is another structure of the tab 015 stacked and bent according to an embodiment of the present application.

[0049] Please refer to FIG. 6, which is an enlarged view of B in FIG. 4. In an embodiment, each group of tabs 153 includes a bent portion 1531 and a flat portion 1533 connected in sequence. One end of the bent portion 1531 is connected with the electrode assembly 013, and the other end is connected with the flat portion 1533. The flat portion 1533 is electrically connected with the bottom of the mounting groove 143. The bent portions 1531 of the two groups of tabs 153 are bent towards each other.

[0050] Specifically, as shown in FIG. 4, the extension of each group of tabs 153 from one end close to the electrode assembly 013 to the other end is: first extending to one groove wall of the mounting groove 143, that is, extending away from the other group of tabs 153, and then gradually bending towards the other group of tabs 153. In this way, the bent portions 1531 of the two groups of tabs 153 are bent towards each other, that is, the inner concave surfaces of the two groups of tabs 153 are arranged opposite to each other along the stacking direction of the tabs 015.

[0051] For example, the side of the flat portion 1533 away from the electrode assembly 013 is in contact with the bottom of the mounting groove 143, so as to increase the contact area between the two and improve the current transmission reliability.

[0052] In the embodiment, the two sets of tabs 153 are arranged in the facing bending structure through the above arrangement. On the one hand, each set of tabs 153 has a larger surface in contact with the inner wall 1432 of the mounting groove 143, so that the current transmission area between each set of tabs 153 and the terminal 014 is larger, and the reliability of current transmission between the set of tabs 153 and the terminal 014 is improved. On the other hand, in order to improve the reliability of current transmission between the set of tabs 153 and the terminal 014, the set of tabs 153 needs to be pressed in the direction perpendicular to the cover plate to increase the abutting force between the set of tabs 153 and the groove bottom of the mounting groove 143, and the abutting force between the set of tabs 153 and the pair of opposite inner walls 1432 of the mounting groove 143. In this case, by arranging the two sets of tabs 153 in the facing bending structure, the two sets of tabs 153 have a spacing, so that the extrusion force of the two sets of tabs 153 on each other is reduced, and the stress state of the set of tabs 153 is improved.

[0053] Referring to FIG. 4 or FIG. 6, in an embodiment, the ends 1536 of the planar portions 1533 of the two sets of tabs 153 are arranged opposite to and spaced from each other.

[0054] Exemplarily, the spacing is between 0.5mm and 4mm. It can be understood that the spacing includes but is not limited to 0.5mm, 0.8mm, 1mm, 1.2mm, 1.5mm, 1.8mm, 2mm, 2.5mm, 3mm, 3.5mm, 3.6mm, 3.8mm, 3.9mm, 4mm.

[0055] In the embodiment, through the above arrangement, on the one hand, when the set of tabs 153 is pressed to cause the ends 1536 of the planar portions 1533 to approach each other, the two sets of tabs 015 are provided with a buffer space to avoid interference between the two sets of tabs 015. On the other hand, when the tabs 015 are heated and expanded, the two sets of tabs 015 are provided with a thermal expansion space to avoid interference between the two sets of tabs 015.

[0056] Referring to FIG. 4 or FIG. 6, in an embodiment, along the arrangement direction of the two sets of tabs 153, the mounting groove 143 has a pair of first groove walls 1431 arranged opposite to each other. The side of the two sets of tabs 153 opposite to each other is a first surface 1534. The first surface 1534 at least partially abuts the first groove wall 1431 adjacent thereto.

[0057] In the embodiment, through the above arrangement, the area of the contact surface between the tab 015 and the inner wall 1432 of the mounting groove 143 can be increased, so that the reliability of the conductive connection between the tab 015 and the terminal 014 can be improved, and the reliability of the battery 001 can be improved.

[0058] Please refer to FIG. 7 and FIG. 8, FIG. 7 is a schematic diagram of the internal structure of another battery 001 provided by the embodiment of the present application, and FIG. 8 is an enlarged view of C in FIG. 7. In an embodiment, a plurality of cutting portions 154 are arranged on the tab 015 along the width direction of the tab 015, and the plurality of cutting portions 154 on the adjacent two layers of tabs 015 correspond to each other, and the plurality of cutting portions 154 separate the tab group 153 into a plurality of spaced tab 015 units.

[0059] In an embodiment, by arranging the cutting portion 154, each layer of tab 015 can be formed by a plurality of smaller sub-tab groups 153, so that the tab 015 can be prevented from being randomly folded during the stacking of the tab 015, the processability of the tab 015 is improved, and the assembly of the battery 001 is facilitated.

[0060] In an embodiment, the plurality of stacked and bent layers of tab 015 are in interference fit with the mounting groove 143 along the thickness direction of the tab 015.

[0061] It can be understood that the tab 015 is a metal layer and has a small thickness and a large flexibility. Therefore, the interference fit of the tab 015 in the thickness direction of the tab 015 facilitates the extrusion of the tab 015 to smoothly enter the mounting groove 143, thereby improving the smoothness of the assembly between the tab 015 and the terminal 014.

[0062] Based on this, in the present embodiment, by the above arrangement, the area of the contact surface and the contact force between the tab 015 and the inner wall 1432 of the mounting groove 143 can be increased, thereby improving the reliability of the electrical connection between the tab 015 and the terminal 014.

[0063] Please refer to FIG. 9, which is a schematic diagram of the size marking at the terminal 014 provided by the embodiment of the present application. In an embodiment, the battery 001 is a square cell, and the cover plate 012 has a width dimension W1 along the width direction of the cover plate 012. The terminal 014 has a width dimension W2, which satisfies: 50%W1≤W2≤W1-2mm.

[0064] 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, W1-3mm, W1-2.8mm, W1-2.6mm, W1-2.5mm, W1-2mm.

[0065] In addition, the cover plate 012 is a plate structure, which has a thickness dimension in the axial direction of the terminal 014, and has a long side and a short side in a plane perpendicular to the axial direction of the terminal 014, and a straight line on which the short side lies is a width direction of the cover plate 012.

[0066] In the embodiment, through the above arrangement, on the one hand, the size of the terminal 014 can be prevented from being too small, so that the reliability of the connection between the terminal 014 and the bus bar can be improved; on the other hand, the size of the terminal 014 can be prevented from being too large to affect the connection between the terminal 014 and the end cover.

[0067] In another embodiment, when the terminal 014 is integrally formed with the cover plate 012, the maximum value of the width dimension W2 of the terminal 014 can be consistent with the width dimension W1 of the cover plate.

[0068] Referring to FIG. 9, in an embodiment, the battery 001 is a square cell, and the inner wall 1432 of the mounting groove 143 has a thickness dimension D in the width direction of the cover plate 012, which satisfies: 0.5mm≤D≤4mm.

[0069] It can be understood that the thickness dimension D of the part opposite to the terminal 014 and 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.

[0070] In the embodiment, through the above limitation, on the one hand, the thickness dimension of the part can be prevented from being too small to cause the terminal 014 to have low strength, so that the strength of the terminal 014 can meet the use requirement; on the other hand, the thickness dimension of the part can be prevented from being too large to cause unnecessary increase of material, so that the material cost of the terminal 014 can be controlled.

[0071] In an embodiment, the tab 015 and the mounting groove 143 are gap-fitted in the width direction of the tab 015.

[0072] The width direction of the tab 015 is the extension direction of the connecting part 1531 between the tab 015 and the pole piece.

[0073] It can be understood that in the width direction of the tab 015, the size of the tab 015 cannot be compressed due to the connection between the tab 015 and the pole piece. Based on this, the fitting between the tab 015 and the mounting groove 143 in the width direction of the tab is set to be gap-fitted, so that the smoothness of the tab 015 into the mounting groove 143 can be improved, and the assembly convenience can be improved.

[0074] Referring to FIG. 2, in an embodiment, the tab 015 has a width dimension W4 along the width direction of the tab 015, and the mounting groove 143 has a first dimension W5, which satisfies 50%W5≤W4≤W5-4mm, and the distance between the two ends of the tab 015 and the inner wall 1432 of the mounting groove 143 adjacent to the tab 015 is consistent with the width direction of the tab 015.

[0075] It can be understood that the width dimension W5-4mm of the tab 015 has a minimum value of 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, W5-4mm.

[0076] In the embodiment, through the above setting, the tab 015 and the mounting groove 143 have a suitable fitting gap in the width direction of the tab 015, which can ensure the smoothness of the assembly of the tab 015 to the mounting groove 143 and also ensure the suitable area of the tab 015 to ensure the current collecting capacity.

[0077] Referring to FIG. 1, in an embodiment, the battery 001 is a square cell, and the cover plate 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.

[0078] It can be understood that when the battery 001 includes two terminals 014 and the second dimension of the two terminals 014 is large, in order to improve the insulation between the two terminals 014, an insulating plate can be arranged between the two terminals 014.

[0079] Exemplarily, the second dimension L2 of the 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, 49%L1.

[0080] Specifically, 10%L1≤L2≤45%L1. Alternatively, 30%L1≤L2≤40%L1.

[0081] In the embodiment, through the above definition, on the one hand, the size of the terminal 014 can be prevented from being too small, so as to improve the reliability of the connection between the terminal 014 and the bus bar, and on the other hand, the size of the terminal 014 can be prevented from being too large to affect the arrangement of other components.

[0082] In an embodiment, the terminal 014 is a rectangular column, and the axis of the terminal 014 is perpendicular to the cover plate.

[0083] Compared with the terminal 014 of other shapes, in the embodiment, through the above setting, the mounting 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.

[0084] 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.

[0085] Please refer to FIG. 1 or FIG. 10, which is a schematic diagram of the internal structure of another battery 001 provided in an embodiment of the application. In an embodiment, the terminal 014 includes a positive terminal 141 and a negative terminal 142. At least one of the positive terminal 141 and the negative terminal 142 is insulated from the cover plate. The tab 015 includes a positive tab 151 and a negative tab 152, and the positive tab 151 is arranged in the mounting groove 143 of the positive terminal 141, and the negative tab 152 is arranged in the mounting groove 143 of the negative terminal 142.

[0086] It can be understood that one of the positive terminal 141 and the negative terminal 142 is insulated from the cover plate, as shown in FIG. 10, one of the terminals 014 is insulated from the cover plate 012 by the 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.

[0087] Alternatively, both the positive terminal 141 and the negative terminal 142 are insulated from the cover plate, as shown in FIG. 1, and the two terminals 014 are insulated from the cover plate 012 by the two insulating members 016, respectively.

[0088] Compared with the battery 001 provided with only one terminal 014, the embodiment provides two terminals 014, which can improve the symmetry of the battery 001, so as to make the force on the battery 001 more symmetrical, thereby improving the force state of the battery 001.

[0089] Please refer to FIG. 2, in an embodiment, the electrode assembly 013 is insulated and attached to or abuts against the cover plate 012.

[0090] The insulating contact between the electrode assembly 013 and the cover plate 012 can be that an insulating layer that does not react with electrolyte is coated on the surface of the cover plate 012 that contacts the electrode assembly 013, that an insulating pad is arranged on the surface of the cover plate 012 that contacts the electrode assembly 013, or that an insulating film is coated on the surface of the electrode assembly 013.

[0091] In the embodiment, the electrode assembly 013 can be filled in the accommodation cavity 111 through the above arrangement, so that the electrode assembly 013 has a larger size, and thus the energy density of the battery 001 can be improved.

[0092] Referring to FIG. 2, in an embodiment, the cover plate 012 is provided with a through hole 121. One end of the through hole 121 communicates with the accommodation cavity 111. Part of the terminal 014 is arranged in the through hole 121.

[0093] The end of the terminal 014 close to the electrode assembly 013 can be located in the through hole 121 or flush with the end of the through hole 121 close to the electrode assembly 013.

[0094] In addition, the terminal 014 includes a positive terminal 141 and a negative terminal 142, and at least one of the terminals 014 is insulated from the cover plate 012.

[0095] In the embodiment, the mating surface of the terminal 014 and the cover plate 012 can be increased through the above arrangement, so that the mating stability of the terminal 014 and the cover plate 012 can be improved, and thus the structural reliability of the battery 001 can be improved.

[0096] In another embodiment, the cover plate 012 is provided with a through hole 121. One end of the through hole 121 communicates with the accommodation cavity 111, and the terminal 014 is arranged on the side of the through hole away from the accommodation cavity 111. Specifically, the terminal 014 can be directly welded on the surface of the cover plate 012 away from the accommodation cavity 111, or a boss can be arranged on the surface of the cover plate 012 away from the accommodation cavity 111, and the boss is inserted into the mounting groove 143. In this way, the welding stress received by the through hole during welding can be reduced, so that the weak part of the cover plate 012 around the through hole can be protected, and thus the strength of the cover plate 012 can be improved.

[0097] Referring to FIG. 2, in an embodiment, the battery 001 further includes an insulating member 016, and the terminal 014 is insulated from the cover plate 012 by the insulating member 016. Specifically, the insulating member 016 has a ring structure and is arranged to extend around the circumference of the through hole, and the end of the insulating member 016 close to the accommodation cavity 111 is flush with the surface of the cover plate 012 close to the accommodation cavity 111. In this way, the insulating member 016 can avoid occupying the accommodation cavity 111, so that the space available for arranging the electrode assembly 013 can be increased, and thus the energy density of the battery 001 can be improved.

[0098] In an embodiment, the cover plate 012 is welded or integrally formed with the shell 011. In the case of welding, the cover plate 012 is located in the opening of the shell 011, and the surface of the cover plate 012 facing away from the accommodation cavity 111 is flush with the end of the formed opening of the shell 011. In addition, in the case of integral forming, it can be cast forming.

[0099] Referring to FIG. 4 or FIG. 5, in an embodiment, at least part of the inner wall 1432 of the mounting groove 143 is in contact with the tab 015. In this way, a larger contact surface can be formed between the mounting groove 143 and the tab 015, thereby improving the reliability of electrical transmission between the tab and the inner wall 1432 of the mounting groove 143.

[0100] Referring to FIG. 11, FIG. 11 is a structural schematic diagram of a battery module 002 provided by an embodiment of the present application. An embodiment of the present application provides a battery module 002, which includes batteries. The batteries are multiple, and the multiple batteries are connected in series and / or in parallel. At least one of the batteries is the battery 001 described above.

[0101] In the above, the multiple batteries can be connected in series, or the multiple batteries can be connected in parallel, or a part of the multiple batteries are connected in series and a part of the multiple batteries are connected in parallel.

[0102] It can be understood that the battery module 002 can further include a battery box, and the battery box has a mounting cavity 021. The multiple batteries 001 are arranged in the mounting cavity 021. The battery module 002 further includes a box body 022 and a box cover 023. The box cover 023 is combined with the box body 022 to define the mounting cavity 021.

[0103] In another embodiment, the battery module 002 includes end plates and a binding belt. The multiple batteries 001 are sequentially stacked between the two end plates. The binding belt binds the end plates and the batteries 001 as a whole.

[0104] In the above, by using the battery 001 described above, the space utilization of the battery module 002 can be higher, and the energy density of the battery module 002 can be improved.

[0105] Referring to FIG. 12, FIG. 12 is a structural schematic diagram of an electrical equipment 003 provided by an embodiment of the present application. An embodiment of the present application provides an electrical equipment 003, which includes the battery 001 described above, and the battery 001 supplies power to the electrical equipment 003. Alternatively, the electrical equipment 003 includes the battery module 002 described above, and the battery module 002 supplies power to the electrical equipment 003.

[0106] It can be understood that the electric device 003 includes but is not limited to electric toys, electric tools, electric vehicles, cars, ships, spacecraft, etc. Among them, the electric toys can include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric plane toys, etc. The spacecraft can include airplanes, rockets, space shuttles, and spaceships, etc. The car can be a fuel car, a gas car, and a new energy car.

[0107] In addition, when the electric device 003 is a car, it can further include a motor 031 and a controller. The motor 031 can be charged by the battery module 002, or the battery module 002 can drive the motor 031 to operate. At the same time, the battery module 002 supplies power to the controller.

[0108] In the embodiment, by using the foregoing battery 001 or battery module 002, when the electric device 003 uses the same volume of battery, it can have a battery with higher energy density, thereby improving the endurance of the electric device 003.

[0109] The technical solutions and technical effects of the present application will be described in detail through specific embodiments below. The following embodiments are only part of the embodiments of the present application, and do not specifically limit the present application.

[0110] The present embodiment aims to investigate the influence of the setting position of the tab 015 on the performance of the battery 001.

[0111] The test content of the embodiment is specifically described as follows:

[0112] I. Test related instructions

[0113] The following test method is DCR test, i.e. Direct Current Resistance test.

[0114] The equipment used for testing is Chroma lithium ion battery test system, which can be of model: 17040E.

[0115] The test environment temperature is: 25±2℃.

[0116] The main operation process of the test is as follows:

[0117] First, take 1C=55A as the nominal capacity, take 1 / 3C, i.e. 18.3Ah as the standard charge and discharge capacity, and take the average value of the actual capacity measured by charging and discharging for 3 cycles as the calibration capacity C0, wherein,

[0118] C0=(∑In*Tn+∑I’n*T’n) / 6,

[0119] In the formula: n is a natural number, and n∈(1,3);

[0120] In represents the charging current during the nth charge.

[0121] Tn is the charging time for the nth time;

[0122] I'n is the nth discharge current;

[0123] T'n is the time of the nth discharge.

[0124] Then charge battery 001 to 4.25V with constant current and constant voltage at 1 / 3C, and cut off current at 0.05C; then adjust the state of charge of battery 001 to 50%SOC with discharge current at 1 / 3C0, and let battery 001 stand for 1 hour.

[0125] Next, with the state of charge of battery 001 at 50% SOC, it was discharged at a constant current of 5C0 for 10s. The voltage difference δU discharge and the discharge current I discharge of battery 001 before and after discharge were recorded. According to the formula: DCR discharge = δU discharge / I discharge, the battery charging DCR with the state of charge of battery 001 at 50% SOC was obtained.

[0126] Meanwhile, with battery 001 at a state of charge of 50% SOC, it was charged at a constant current of 5C0 for 10s, and the voltage difference δU_charging and the charging current I_charging before and after charging were recorded. According to the formula: DCR_charging = δU_charging / I_charging, the battery discharge DCR with battery 001 at a state of charge of 50% SOC was obtained.

[0127] II. Test Results

[0128] The test subject is a square-shell battery with a length of 148mm, a width of 91mm, and a thickness of 26.5mm. The main difference between the test subjects is whether the tab 015 is located inside the terminal 014. The test targets are the temperature at the center of the electrode assembly 013 of battery 001 and the charge / discharge DCR of battery 001.

[0129] 2.1 Setting up a control group

[0130] The control group consists of batteries in related technologies where the tabs are located outside the terminals. Test data is as follows:

[0131] Group Structure Battery Capacity / Ah Energy Density / Wh / kg @50%SOC Battery Discharge DCR / mΩ @50%SOC Battery Charge DCR / mΩ 5C=280A Working for 15min Temperature Rise in the Middle of Battery 001 / ℃ Control Group 1 Tab 015 Located Outside the Terminal 55280 0.31±0.05 0.34±0.0517

[0132] Table 1. Structure and validation results of control group 1

[0133] According to Table 1, the relevant data of the battery 001 with the tab 015 outside the terminal 014, 148 mm in length, 91 mm in width, and 26.5 mm in thickness are as follows:

[0134] (1) The battery capacity is 55 Ah;

[0135] (2) The energy density of the battery 001 is 280 Wh / kg;

[0136] (3) At a state of charge of 50% SOC of the battery 001, the battery charging DCR is 0.34±0.05 mΩ, and the battery discharging DCR is 0.31±0.05;

[0137] (4) After working for 15 minutes at a charging and discharging current of 5C=280A, the temperature rise of the center of the electrode assembly 013 of the battery 001 is 17℃.

[0138] 2.2 Under the premise that the external dimensions of the battery 001 are the same, the positive tab 151 is arranged in the mounting groove 143 of the positive terminal 141, the negative tab 152 is arranged in the mounting groove 143 of the negative terminal 142, and the electrode assembly 013 is extended to the slot opening 1433 of the mounting groove 143, so that the positive plate is connected with the positive tab 151, and the negative plate is connected with the negative tab 152.

[0139] Based on the battery 001 with the above structure, the test data are as follows:

[0140] Group Structure Battery Capacity / Ah Energy Density / Wh / kg @50% SOC Battery Discharge DCR / mΩ @50% SOC Battery Charge DCR / mΩ 5C=280A Working for 15 min Temperature Rise of Battery 001 in the Middle / ℃ Example 1 Tab 015 inside the terminal 014, electrode assembly 013 extended to the slot opening 1433 of the mounting groove 143 and connected with the tab 015 59 3000 0.22±0.05 0.27±0.05

[0141] Table 2. Structure and verification results of Example 1

[0142] According to Table 2, the relevant data of the battery with the tab 015 inside the terminal 014, 148 mm in length, 91 mm in width, and 26.5 mm in thickness are as follows:

[0143] (1) The battery capacity is 59 Ah;

[0144] (2) The energy density of the battery 001 is 300 Wh / kg;

[0145] (3) At a state of charge of 50% SOC of the battery 001, the battery charging DCR is 0.22±0.05 mΩ, and the battery discharging DCR is 0.27±0.05;

[0146] (4) With 5C=280A as the charge-discharge current, the temperature rise of the center position of the electrode assembly 013 of the battery 001 is 9°C after working for 15 minutes.

[0147] Comparing Example 1 and Control Group 1, it can be seen that, by locating the tab 015 inside the terminal 014, extending the electrode assembly 013 to the notch 1433 of the mounting groove 143, and connecting the tab 015, the following changes can be obtained:

[0148] (1) The battery capacity is increased from 55Ah to 59Ah;

[0149] (2) The energy density of the battery 001 is increased from 280Wh / kg to 300Wh / kg;

[0150] (3) At the state of charge of the battery 001 of 50% SOC, the battery charge DCR is reduced from 0.34±0.05 mΩ to 0.22±0.05 mΩ, and the battery discharge DCR is reduced from 0.31±0.05 to 0.27±0.05;

[0151] (4) With 5C=280A as the charge-discharge current, the temperature rise of the center position of the electrode assembly 013 of the battery 001 is reduced from 17°C to 9°C after working for 15 minutes.

[0152] As can be seen from the above, under the premise that the external dimensions of the battery 001 remain unchanged, by locating the tab 015 inside the terminal 014, extending the electrode assembly 013 to the notch 1433 of the mounting groove 143, and connecting the tab 015, the battery capacity and the energy density of the battery 001 can be increased, the battery charge-discharge DCR can be reduced, and the temperature rise inside the battery 001 can also be reduced.

Claims

1. A battery (001), comprising: Casing (011); A cover plate (012) closes to the housing (011) to define a receiving cavity (111); An electrode assembly (013) is disposed within the receiving cavity (111); A terminal (014) is disposed on the cover plate (012) and protrudes from the side of the cover plate (012) away from the receiving cavity (111). A mounting groove (143) is provided on the side of the terminal (014) near the receiving cavity (111), and the mounting groove (143) communicates with the receiving cavity (111). And a tab (015) is disposed in the mounting groove (143) and electrically connected to the inner wall (1432) of the mounting groove (143); The electrode assembly (013) extends to the slot (1433) of the mounting groove (143) and is connected to the tab (015).

2. The battery (001) according to claim 1, wherein, The electrode tab (015) has multiple layers, and the multiple layers of electrode tab (015) are stacked and bent in the mounting groove (143).

3. The battery (001) according to claim 2, wherein, Along the stacking direction of the tabs (015), the multiple tabs (015) are divided into two tab groups (153), and the two tab groups (153) are stacked and bent in the mounting groove (143).

4. The battery (001) according to claim 3, wherein, Each of the electrode assembly (153) includes a bent portion (1531) and a flat 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 flat portion (1533). The flat portion (1533) is electrically connected to the bottom of the mounting groove (143). The bent portions (1531) of the two tab assemblies (153) bend toward each other.

5. The battery (001) according to claim 4, wherein, The ends (1536) of the planar portions (1533) of the two electrode assemblies (153) are opposite to each other and spaced apart.

6. The battery (001) according to claim 4 or 5, wherein, Along the arrangement direction of the two tab assemblies (153), the mounting groove (143) has a pair of opposing first groove walls (1431), and the side of the two tab assemblies (153) facing away from each other is a first surface (1534), which is at least partially in contact with the first groove wall (1431) adjacent to it.

7. The battery (001) according to any one of claims 3-5, wherein, Along the width direction of the tab (015), the tab (015) is provided with a plurality of cutouts (154), and the plurality of cutouts (154) on two adjacent layers of tabs (015) correspond one-to-one. The plurality of cutouts (154) divide the tab group (153) into a plurality of tab units (1535) arranged at intervals.

8. The battery (001) according to any one of claims 2-5, wherein, The multiple layers of the tabs (015) stacked and bent along the thickness direction are interference-fitted with the mounting groove (143).

9. The battery (001) according to any one of claims 1-5, wherein, The battery (001) is a square-shell battery (001). Along the width direction of the cover plate (012), the cover plate (012) has a width dimension W1, and the terminal (014) has a width dimension W2, satisfying: 50%W1≤W2≤W1-2mm.

10. The battery (001) according to any one of claims 1-5, wherein, The battery (001) is a square-shell battery (001). Along the width direction of the cover plate (012), the inner wall (1432) of the mounting groove (143) has a thickness dimension D, which satisfies: 0.5mm≤D≤4mm.

11. The battery (001) according to any one of claims 1-5, wherein, Along the width direction of the tab (015), the tab (015) is clearance-fitted with the mounting groove (143).

12. The battery (001) according to claim 11, wherein, 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 inner wall (1432) of the adjacent mounting groove (143) is consistent.

13. The battery (001) according to any one of claims 1-5, wherein, The battery (001) is a square-shell battery (001). Along the width direction of the tab (015), the cover plate (012) has a length dimension L1, and the terminal (014) has a second dimension L2, satisfying: 10%L1≤L2<50%L1.

14. The battery (001) according to any one of claims 1-5, wherein, The terminal (014) is a rectangular column with its axis perpendicular to the cover plate (012).

15. The battery (001) according to any one of claims 1-5, wherein, The terminal (014) includes a positive terminal (141) and a negative terminal (142), at least one of the positive terminal (141) and the negative terminal (142) being insulated from the cover plate (012); the tab (015) includes a positive tab (151) and a negative tab (152), the positive tab (151) being disposed in the mounting groove (143) of the positive terminal (141), and the negative tab (152) being disposed in the mounting groove (143) of the negative terminal (142).

16. The battery (001) according to any one of claims 1-5, wherein, The electrode assembly (013) is insulatedly bonded to or insulatedly abutted against the cover plate (012).

17. The battery (001) according to any one of claims 1-5, wherein, The cover plate (012) is provided with a through hole (121), one end of which is connected to the receiving cavity (111), and part of the terminal (014) passes through the through hole (121).

18. The battery (001) according to any one of claims 1-5, wherein, The cover plate (012) is provided with a through hole (121), one end of which is connected to the receiving cavity (111), and the terminal (014) is provided on the side of the through hole (121) away from the receiving cavity (111).

19. The battery (001) according to any one of claims 1-5, wherein, The battery (001) also includes an insulating element (016), and the terminal (014) is insulated from the cover plate (012) by the insulating element (016).

20. The battery (001) according to claim 19, wherein, The end of the insulating element (016) near the receiving cavity (111) is flush with the surface of the cover plate (012) facing the receiving cavity (111).

21. The battery (001) according to any one of claims 1-5, wherein, The cover plate (012) is welded to or integrally formed with the shell (011).

22. The battery (001) according to any one of claims 1-5, wherein, At least part of the inner wall (1432) of the mounting groove (143) is in contact with the tab (015).

23. The battery (001) according to any one of claims 1-5, wherein, The battery (001) is one of the following types of batteries (001): square-shell battery, cylindrical battery, prismatic battery, irregularly shaped battery, and button battery.

24. A battery module (002), comprising: A battery (001), wherein there are multiple batteries (001), the multiple batteries (001) are connected in series and / or in parallel, and at least one of the batteries (001) is a battery (001) as described in any one of claims 1-23.

25. An electrical device (003) comprising a battery (001) as described in claims 1-23, wherein the battery (001) supplies power to the electrical device (003); Alternatively, it may include the battery module (002) as described in claim 24, wherein the battery module (002) supplies power to the electrical device (003).

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