High-capacity battery

Abstract

The present utility model relates to a high-capacity battery, comprising: a square case, one lower end of the square case being open, a cover plate being connected and hermetically fixed to the lower end, two expansion grooves being formed on an inner side of one upper end of the square case, the bottom of each of the two expansion grooves being provided with an assembly hole, the two assembly holes being hermetically sealed with a positive electrode terminal and a negative electrode terminal, respectively, in an insulating manner, and the positive electrode terminal and the negative electrode terminal extending into the two expansion grooves, respectively; and an electrode core, provided in the square case, in which the end of the electrode core near the expansion grooves is provided with a positive electrode tab and a negative electrode tab. Figure 1

Description

Title of the invention: High-capacity battery technical field

[0001] The present utility model relates to the field of battery technology and, in particular, a high-capacity battery.

[0002] BACKGROUND

[0003] With the continued development of electric vehicles, people are becoming increasingly demanding in terms of electric vehicles. In the sector, challenges are ongoing regarding range, and models with a range of over 800 km are appearing one after another.

[0004] The solution to increase battery life is to improve the volumetric utilization rate of a battery. Currently, the design concept for a square battery mainly consists of providing a cover plate structure on top and connecting the electrode tabs of an electrode core to the poles of the cover plate. It is necessary to reserve space at the top of a casing to accommodate the electrode tabs. Furthermore, the rounded corners of the bottom of the casing interfere with the electrode core, so when the battery cycles and expands, a dead zone is generated where the interference occurs, thereby reducing the battery's lifespan. It is therefore necessary to provide a lower support to raise the electrode core in order to avoid any interference between the electrode core and the rounded corners at the bottom of the casing.In the current design of the square battery, space must be reserved at the top of the casing to accommodate the electrode tabs, and a lower support must be provided at the bottom to lift an electrode core, which significantly limits the volumetric utilization rate of the square casing. Therefore, it is important to increase the effective usable space for the electrode tabs and to increase the effective utilization rate of a stacked or wound core.

[0005] SUMMARY

[0006] On this basis, to solve the technical problem of a rather limited volumetric utilization rate of current square batteries, certain embodiments of the present utility model provide a high-capacity battery.

[0007] Certain embodiments of the present utility model provide a high-capacity battery, including:

[0008] a square housing, one lower end of the square housing being open, a cover plate being connected and fixed in a watertight manner to the lower end, two expansion grooves being formed on an inner side of one upper end of the square housing, a bottom of each of the two expansion grooves being provided with a assembly hole, the two assembly holes being provided in a sealed manner with a positive electrode terminal and a negative electrode terminal, respectively, in an insulating manner, and the positive electrode terminal and the negative electrode terminal extending into the two expansion grooves, respectively; and

[0009] an electrode core, supplied in the square housing and provided at its upper end with a positive electrode tab and a negative electrode tab which extend into the two expansion grooves, respectively, in which the positive electrode tab and the negative electrode tab are electrically connected to the positive electrode terminal and the negative electrode terminal, respectively.

[0010] In the present utility model, the structure of the square case is improved. Two expansion grooves are provided at the top of the square case, used to assemble the positive electrode terminal and the negative electrode terminal, respectively, and can also be used to expand the extension spaces of the positive electrode tab and the negative electrode tab, respectively; and an opening is provided at the bottom of the square case and the cover plate is connected and fixed in a watertight manner to the bottom; a rounded corner structure at the bottom of the square case is eliminated, so the bottom of the electrode core is not obstructed, so that a lower support structure can be eliminated, which effectively increases the space utilization rate in the Z direction of the square case, thereby increasing the space utilization rate occupied by the electrode core inside the square case, thereby increasing the energy density of the battery.

[0011] To further improve the described solution of the present utility model, two outwardly projecting parts are formed at the upper end of the square housing by means of a stamping, and the inside of each of the two projecting parts forms a corresponding expansion groove.

[0012] To further improve the described solution of the present utility model, each of the salient parts has an arc-shaped cross-section or a square cross-section.

[0013] To further improve the described solution of the present utility model, sealing rings are sleeved onto the positive electrode terminal and the negative electrode terminal respectively, and the positive electrode terminal and the negative electrode terminal are insulated from the square housing and sealed to it by means of the sealing rings.

[0014] To further improve the described solution of the present utility model, both the positive electrode terminal and the negative electrode terminal have an inverted T-shaped structure, and the cross-sections of the positive electrode terminal and of The negative electrode terminal is soldered and connected to the positive electrode tab and the negative electrode tab, respectively.

[0015] To further improve the described solution of the present utility model, the positive electrode tab has a curved portion in the corresponding expansion groove, the curved portion is disposed above the cross-section of the positive electrode terminal, and the curved portion of the positive electrode tab is welded and connected to the upper surface of the cross-section of the positive electrode terminal; the negative electrode tab has a curved portion in the corresponding expansion groove, the curved portion of the negative electrode tab is disposed above the cross-section of the negative electrode terminal, and the curved portion of the negative electrode tab is welded and connected to the upper surface of the cross-section of the negative electrode terminal;and insulating films are provided on the internal walls of the two expansion grooves in positions corresponding to the curved parts of the positive electrode tab and the negative electrode tab, respectively. The positive electrode tab and the negative electrode tab are directly welded to the positive electrode terminal and the negative electrode terminal, respectively, so that connecting parts are eliminated, which further saves the space occupied in the square case in the vertical direction, improving the overall current-carrying capacity of the battery's structural elements; and an insulating film is provided near each electrode tab, which provides insulation and protection, and also increases the thermal conduction efficiency between the electrode tabs and the square case, so that heat can be transferred to the outside in a timely manner.

[0016] To further improve the solution described in this utility model, the two sealing rings extend to the outer side of the square housing and make contact with its outer lateral surface. Two pressure plates are welded respectively to the ends of the positive electrode terminal and the negative electrode terminal extending from the outer side of the square housing, and these two pressure plates press against the two sealing rings. The presence of these pressure plates ensures sealing performance at the positions of the positive and negative electrode terminals.

[0017] Another improvement to the solution described in this utility model is that the cover plate is connected and fixed in a hermetic manner to the open end of the square case by means of a lateral weld or a vertical weld, ensuring the overall sealing and mechanical performance of the battery.

[0018] To further improve the solution described in the present utility model, the depth of each of the expansion grooves is 1 to 3 mm. By providing expansion grooves of 1 to 3 mm, it is possible to save 1 to 3 mm of space in the vertical direction of the square housing.

[0019] To further improve the described solution of the present utility model, the distance between an edge of the positive electrode terminal and an inner wall of the corresponding expansion groove and the distance between an edge of the negative electrode terminal and an inner wall of the corresponding expansion groove are both 2 to 3 mm.

[0020] Compared with the prior art, the present utility model has the following beneficial effects:

[0021] 1. In the present utility model, the structure of the square casing is improved. Two Expansion grooves are provided at the top of the square casing to accommodate the positive and negative electrode tabs of the electrode core, respectively, allowing the positive and negative electrode tabs to remain within the internal space of the square casing. Furthermore, the bottom of the square casing is open, and the cover plate is connected and securely fixed to the bottom. A rounded-corner structure at the bottom of the square casing is eliminated, thus unobstructing the electrode core and eliminating the need for a lower support structure. In summary, the space utilization rate in the Z direction of the square casing is effectively increased, as is the utilization rate of the space occupied by the electrode core within the square casing, thereby increasing the battery's energy density.

[0022] 2. In the present utility model, the bottoms of the positive electrode terminal and of The negative electrode terminal is directly welded to the positive electrode tab and the negative electrode tab respectively inside their corresponding expansion grooves, so that the positive electrode terminal and the negative electrode terminal do not occupy the internal space of the square case; in addition, connecting parts are also eliminated, which further saves the space occupied in the square case in the vertical direction, improving the overall current carrying capacity of the structural elements of the battery.Furthermore, due to the thickness of the sealing rings, the portion of each sealing ring disposed within the corresponding expansion groove forms a certain space along its outer periphery; in the present utility model, the curved portions of the positive electrode tab and the negative electrode tab pass over the outer edges of the corresponding terminals, respectively, and penetrate the spaces, such that the curved portions of the positive electrode tab and the negative electrode tab overlap the upper surfaces of the corresponding terminals. respectively, and are welded to them, thereby saving space to increase the utilization rate of the space occupied by the electrode core inside the square housing. In the present utility model, the height of the space saved = the thickness of the eliminated connecting pieces (0.4 mm to 1.5 mm) + the thickness of the terminal cross-sections (1 mm to 1.5 mm) + the thickness of the electrode tabs. Brief description of the drawings

[0023] Fig. 1 is a structural diagram of a high-capacity battery according to embodiments of the present utility model;

[0024] [Fig.2] is a top view of [Fig.1];

[0025] [Fig.3] is a cross-sectional view taken along line AA of [Fig.2];

[0026] [Fig.4] is a cross-sectional view in another direction of [Fig.2];

[0027] [Fig.5] is an enlarged view of part B of [Fig.3];

[0028] [Fig.6] is a partial enlarged view of [Fig.4];

[0029] [Fig.7] is a partial enlarged view of [Fig.5].

[0030] Reference symbols: 1. square housing; 2. cover plate; 3. expansion groove; 4. positive electrode terminal; 5. negative electrode terminal; 6. electrode core; 7. positive electrode tab; 8. protruding part; 9. sealing ring; 10. insulating film; 11. pressure plate; 12. pressure relief valve; 13. liquid injection hole

[0031] DETAILED DESCRIPTION OF THE EMBODIMENT METHODS

[0032] To facilitate understanding of this utility model, it will be described in more detail below with a view to specific embodiments. This utility model can, however, be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to make the utility model of this utility model complete and exhaustive.

[0033] Unless otherwise defined, all technical and scientific terms used in this text have the same meaning as that commonly understood by a person competent in the related technical field of this utility model. The terminology used in the description of this utility model is solely for the purpose of describing particular embodiments and is not intended to limit this utility model.

[0034] With reference to [Fig.1] to 4, this embodiment provides a high-capacity battery, including a square case 1 and an electrode core 6.

[0035] In this embodiment, the lower end of the square housing 1 is open, and a cover plate 2 for sealing the lower end of the square housing 1 is connected to it by lateral or vertical welding. As shown in the [Fig. 4] and 5, two outwardly projecting portions 8 are formed at the upper end of the square housing 1 by means of a stamping process, and the inside of each of the two projecting portions 8 forms an expansion groove 3. In this embodiment, each of the two projecting portions 8 has a square cross-section. Of course, in other embodiments, each of the two projecting portions 8 may also have a structure with an arc-shaped cross-section. Each of the two projecting portions 8 has an assembly hole through it. A positive electrode terminal 4 and a negative electrode terminal 5 are provided in the two assembly holes, respectively. Sealing rings 9 are sleeved onto the positive electrode terminal 4 and the negative electrode terminal 5, respectively, each of the sealing rings 9 extending towards the outer lateral surface of the corresponding projecting portion 8.The sealing rings 9 ensure a seal between the positive electrode terminal 4 and the square housing 1 and between the negative electrode terminal 5 and the square housing 1.

[0036] In this embodiment, the positive electrode terminal 4 and the negative electrode terminal 5 both have a T-shaped structure, and the cross-sections of the positive electrode terminal 4 and the negative electrode terminal 5 extend into the two expansion grooves 3, respectively. Two pressure plates 11 are connected to the ends of the positive electrode terminal 4 and the negative electrode terminal 5 located outside the square housing 1, and the two pressure plates 11 bear against the two sealing rings 9, respectively.

[0037] An electrode core 6 is provided in the square housing 1; a positive electrode tab 7 and a negative electrode tab are formed at the upper end of the electrode core 6, are arranged to correspond to the two expansion grooves 3, respectively, and the positive electrode tab 7 and the negative electrode tab extend into the two expansion grooves 3, respectively; the curved parts of the positive electrode tab 7 and the negative electrode tab extend to the upper surfaces of the cross sections of the positive electrode terminal 4 and the negative electrode terminal 5, respectively, and are connected by welding to the positive electrode terminal 4 and the negative electrode terminal 5, respectively, at the upper surfaces of the cross sections of the positive electrode terminal 4 and the negative electrode terminal 5;and an insulating film 10 is provided between each welding position and the inner wall of the corresponding expansion groove 3. In this embodiment, the electrode core 6 has a stacked structure. Of course, in other embodiments, the electrode core 6 may also have a wound structure. In this embodiment, in order to allow the positive electrode tab 7 and the negative electrode tab to enter the expansion grooves 3, the width and; The length of each expansion groove 3 must meet the following condition: the distance between the inner wall of the corresponding expansion groove 3 and the edge of the positive electrode terminal 4 and the distance between the inner wall of the corresponding expansion groove 3 and the edge of the negative electrode terminal 5 are both 2 to 3 mm.

[0038] In this embodiment, the housing is provided with a decompression valve 12 and an injection hole 13 in a place located between the two protruding parts 8. Of course, in other embodiments, the decompression valve 12 and the injection hole 13 can also be provided on the cover plate 2.

[0039] By means of the structural arrangement described, when the battery of the present embodiment is assembled, the positive electrode tab 7 and the negative electrode tab of the stacked electrode core 6 are first brought together and centered, and as shown in [Fig.7], the curved parts of the positive electrode tab 7 and the negative electrode tab pass over the edges of the cross sections of the positive electrode terminal 4 and the negative electrode terminal, respectively, and cover the upper surfaces of the cross sections of the positive electrode terminal 4 and the negative electrode terminal, respectively, and the curved parts of the positive electrode tab 7 and the negative electrode tab are welded to the upper surfaces of the cross sections of the positive electrode terminal 4 and the negative electrode terminal, respectively, by means of a butterfly weld;next, the square housing 1 is oriented with its opening downwards to allow upside-down mounting on the electrode core 6, so that the positive electrode terminal 4 and the negative electrode terminal 5 pass through the two assembly holes, respectively; the amount of compression of the sealing ring 9 is controlled by controlling the displacement, which avoids interference between the positions of the corners of the electrode core 6 and the rounded corners of the square housing 1, thus extending the service life; then the two pressure plates 11 are welded to the upper parts of the positive electrode terminal 4 and the negative electrode terminal 5, respectively, and the terminals, the sealing rings 9, the protruding parts 8, etc., are encapsulated by the pressure plates 11, ensuring sealing at the positions of the positive electrode terminal 4 and the negative electrode terminal 5;Finally, the cover plate 2 and the open end of the square case 1 are welded by side welding or vertical welding, ensuring the overall sealing and mechanical performance of the battery.

[0040] In this embodiment, the structure of the square housing 1 is improved. Two expansion grooves 3 are provided at the top of the square housing 1 to provide housing spaces for the positive electrode tab 7 and the negative electrode tab of the electrode core 6, respectively, allowing the electrode tab positive 7 and the negative electrode tab not to occupy the internal space of the square case 1; an opening is provided at the bottom of the square case 1 and the cover plate 2 is connected and fixed in a sealed manner to the bottom; a structure with rounded corners at the bottom of the square case 1 is eliminated, so that the electrode core 6 is not obstructed, so that a lower support structure can be eliminated, which effectively increases the space utilization rate in the Z direction of the square case 1, thereby increasing the space utilization rate occupied by the electrode core 6 inside the square case 1, thereby increasing the energy density of the battery.In this embodiment, the bottoms of the positive electrode terminal 4 and the negative electrode terminal 5 are housed in the two expansion grooves 3, respectively, and are directly welded with the positive electrode tab 7 and the negative electrode tab, respectively, so that the positive electrode terminal 4 and the negative electrode terminal 5 do not occupy the internal space of the square case 1; in addition, connecting parts are also eliminated, which further saves the space occupied in the square case 1 in the vertical direction, improving the overall current carrying capacity of the structural elements of the battery.Furthermore, due to the thickness of the sealing rings 9, a portion of the periphery where each sealing ring 9 is located in the corresponding expansion groove 3 forms a certain space; in the present utility model, the curved portions of the positive electrode tab 7 and the negative electrode tab pass over the external edges of the corresponding terminals, respectively, and enter the spaces, such that the curved portions of the positive electrode tab 7 and the negative electrode tab overlap and are welded to the upper surfaces of the corresponding terminals, respectively, thus saving space to increase the utilization rate of the space occupied by the electrode core 6 inside the square housing 1.In this embodiment, the height of the space saved = the thickness of the eliminated connecting pieces (0.4 to 1.5 mm) + the thickness of the terminal cross-sections (1 to 1.5 mm) + the thickness of the electrode tabs.

[0041] The technical features of the described embodiments can be combined in any way, and for the sake of brevity, not all possible combinations of the technical features of the described embodiments are described. However, as long as the combinations of these technical features are not contradictory, all such combinations shall be considered as falling within the scope of the description.

[0042] The above embodiments simply express several implementations of the present utility model and are described in detail. However, the embodiments should not be interpreted as limiting the scope of the present Utility model. It should be noted that, for a technically competent person, various changes and modifications can be made without departing from the spirit and scope of this utility model, and that all such changes and modifications fall within the scope of protection of this utility model. Therefore, the scope of protection of this utility model is defined by the supplementary claims.

Claims

Demands

1. High-capacity battery, comprising: a square case (1), a lower end of the square case being open, a cover plate (2) being connected and hermetically fixed to the lower end, two expansion grooves (3) being formed on an inner side of an upper end of the square case, a bottom of each of the two expansion grooves (3) being provided with an assembly hole, two assembly holes being hermetically provided with a positive electrode terminal (4) and a negative electrode terminal (5), respectively, in an insulating manner, and the positive electrode terminal (4) and the negative electrode terminal (5) extending into the two expansion grooves (3), respectively;and an electrode core (6), supplied in the square housing (1) and provided at its upper end with a positive electrode tab (7) and a negative electrode tab extending into the two expansion grooves, respectively, in which the positive electrode tab and the negative electrode tab are electrically connected to the positive electrode terminal (4) and the negative electrode terminal (5), respectively.;

2. High capacity battery according to claim 1, wherein two outwardly projecting parts (8) are formed at the upper end of the square case (1) by means of a stamping, and the inside of each of the two projecting parts (8) forms a corresponding expansion groove (3) in the two expansion grooves.

3. High-capacity battery according to claim 2, wherein each of the two protruding parts (8) has an arc-shaped cross-section or a square cross-section.

4. High capacity battery according to claim 1, wherein sealing rings (9) are sleeved on the positive electrode terminal (4) and the negative electrode terminal (5) respectively, and the positive electrode terminal (4) and the negative electrode terminal (5) are insulated from the square case (1) and sealed to it by the sealing rings (9).

5. High-capacity battery according to claim 1, wherein the positive electrode terminal (4) and the negative electrode terminal (5) both have an inverted T-shaped structure, cross sections of the positive electrode terminal (4) and the negative electrode terminal (5) extend into the two expansion grooves (3), respectively, and the cross sections of the positive electrode terminal (4) and the negative electrode terminal (5) are welded and connected to the positive electrode tab (7) and the negative electrode tab, respectively.

6. High-capacity battery according to claim 5, wherein the positive electrode tab (7) has a curved portion in a corresponding expansion groove (3), the curved portion is disposed above the cross-section of the positive electrode terminal (4), and the curved portion of the positive electrode tab (7) is welded and connected to an upper surface of the cross-section of the positive electrode terminal (4); the negative electrode tab has a curved portion in the corresponding expansion groove (3), the curved portion of the negative electrode tab is disposed above the cross-section of the negative electrode terminal (5), and the curved portion of the negative electrode tab is welded and connected to the upper surface of the cross-section of the negative electrode terminal (5);and insulating films (10) are provided on the inner walls of the two expansion grooves (3) in positions corresponding to the curved parts of the positive electrode tab (7) and the negative electrode tab, respectively.;

7. High capacity battery according to claim 4, wherein the two sealing rings (9) extend towards an external side of the square case (1) and make contact with an external lateral surface of the square case (1), two pressure plates (11) are welded respectively to the end of the positive electrode terminal (4) and to the end of the negative electrode terminal (5) extending from the external side of the square case (1), and the two pressure plates (11) press against the two sealing rings (9), respectively.

8. High capacity battery according to claim 1, in which the cover plate (2) is connected and hermetically fixed to an open end of the square case (1) by means of a lateral weld or a vertical weld.

9. High capacity battery according to claim 1, wherein the depth of each of the expansion grooves (3) is from 1 mm to 3 mm.

10. High capacity battery according to claim 1, wherein the distance between an edge of the positive electrode terminal (4) and an inner wall of a corresponding expansion groove (3) and the distance between an edge of the negative electrode terminal (5) and an inner wall of a corresponding expansion groove (3) are both 2 mm to 3 mm.

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