Lithium ion battery

Abstract

The utility model provides a lithium ion battery. The lithium ion battery comprises a mounting shell, wherein a positive pole column and a negative pole column are arranged on the mounting shell; the multiple winding battery cells are arranged in the mounting shell in rows in the X direction and / or in columns in the Z direction, and each winding battery cell comprises a winding cell body, a positive electrode lug part and a negative electrode lug part; the positive electrode connecting component is connected with the positive electrode column, and the positive electrode connecting component is connected with the plurality of positive electrode lug parts and is positioned on the same side of the roll core body; the negative electrode connecting component is connected with the negative electrode column, the negative electrode connecting component is connected with the negative electrode lug parts and located on the same side of the roll core body, and an included angle is formed between the X direction and the Z direction. According to the technical scheme, the problems that in the prior art, lithium ion batteries are low in manufacturing efficiency and low in yield, and pseudo soldering is prone to occurring in the laser welding process are solved.

Description

Technical Field

[0001] The utility model relates to the technical field of lithium ion batteries, in particular to a lithium ion battery. Background Art

[0002] In the prior art, the internal structure of the short blade battery of lithium batteries is mostly assembled using a single stacked cell. Since the manufacturing process of the stacked cell requires stacking positive / negative electrode sheets layer by layer, the forming efficiency of the stacked cell is slower than that of the wound cell, which has become a bottleneck in the manufacturing efficiency of the short blade battery.

[0003] In addition, due to the easy misalignment and sliding between the positive and negative electrodes inside the stacked battery cell, its manufacturing qualification rate is lower than that of the wound battery cell. When the design capacity of the short blade battery is large, the number of stacking layers and electrode size required for a single stacked battery cell will increase rapidly, greatly increasing the risk of short blade batteries being scrapped due to short circuits during the manufacturing process.

[0004] In addition, the positive and negative poles of the existing short blade battery are located at both ends respectively. It is necessary to first insert a single stacked battery cell into an aluminum shell, and then directly weld the pole tabs to the poles using a laser. When the design capacity of the short blade battery is larger, the number of pole tab layers and the total thickness become larger, and the laser welding between multiple layers of pole tabs is prone to the risk of cold welding. Utility Model Content

[0005] The main purpose of the utility model is to provide a lithium ion battery to solve the problems of low manufacturing efficiency and low yield of lithium ion batteries in the prior art and easy occurrence of cold welds during laser welding.

[0006] In order to achieve the above-mentioned purpose, the utility model provides a lithium-ion battery, comprising: a mounting shell, on which a positive electrode column and a negative electrode column are provided; a plurality of wound battery cells are arranged in rows along the X direction and / or in columns along the Z direction in the mounting shell, each wound battery cell comprising a winding core body, a positive electrode ear portion and a negative electrode ear portion; a positive electrode connecting member connected to the positive electrode column, the positive electrode connecting member being connected to the plurality of positive electrode ears and being located on the same side of the winding core body; a negative electrode connecting member connected to the negative electrode column, the negative electrode connecting member being connected to the plurality of negative electrode ears and being located on the same side of the winding core body, and being arranged at an angle between the X direction and the Z direction.

[0007] Furthermore, along the X direction, the positive electrode column and the negative electrode column are respectively located on opposite sides of the mounting shell; the positive electrode connecting component includes a first positive connecting plate and a second positive connecting plate that are connected and arranged at an angle, a plurality of positive electrode ears are connected to the first positive connecting plate, and the positive electrode column is connected to the second positive connecting plate; the negative electrode connecting component includes a first negative connecting plate and a second negative connecting plate that are connected and arranged at an angle, a plurality of negative electrode ears are connected to the first negative connecting plate, and the negative electrode column is connected to the second negative connecting plate.

[0008] Furthermore, the plurality of wound battery cells are arranged in sequence along the X direction, each positive electrode ear is bent and welded to the first positive connecting sheet, and each negative electrode ear is bent and welded to the first negative connecting sheet.

[0009] Furthermore, the plurality of wound battery cells are arranged in rows and columns along the X direction and the Z direction, each positive electrode ear is bent and welded to the first positive connecting piece, and each negative electrode ear is bent and welded to the first negative connecting piece.

[0010] Furthermore, along the Z direction, the bending directions of the negative pole ears of two adjacent wound battery cells are the same, a positive pole avoidance groove is provided on the first positive connecting sheet, and the negative pole ear of one of the two adjacent wound battery cells passes through the positive pole avoidance groove; along the Z direction, the bending directions of the positive pole ears of two adjacent wound battery cells are the same, a negative pole avoidance groove is provided on the first negative connecting sheet, and the negative pole ear of one of the two adjacent wound battery cells passes through the negative pole avoidance groove.

[0011] Furthermore, along the Z direction, the bending directions of the negative electrode ears of two adjacent wound battery cells are opposite; along the Z direction, the bending directions of the positive electrode ears of two adjacent wound battery cells are opposite.

[0012] Furthermore, the mounting shell includes: a shell; a positive electrode cover plate; a negative electrode cover plate, along the X direction, the positive electrode cover plate and the negative electrode cover plate are respectively connected to two sides of the shell, a positive electrode column is provided on the positive electrode cover plate, and a negative electrode column is provided on the negative electrode cover plate.

[0013] Furthermore, the shell includes a first half shell and a second half shell connected to each other, and the first half shell and the second half shell are respectively arranged on two sides of the plurality of wound battery cells.

[0014] Furthermore, a limiting component is provided on the first half shell, and a limiting groove is provided on the second half shell, and the limiting groove and the limiting component are matched in a limiting manner.

[0015] Furthermore, an insulating film is provided between the multiple wound battery cells and the inner wall of the shell; and / or an insulating gasket is provided between the positive electrode column and the positive electrode cover plate, and an insulating gasket is provided between the negative electrode column and the negative electrode cover plate.

[0016] By applying the technical solution of the utility model, on the one hand, compared with the prior art that uses stacked cells to realize the short blade battery structure, the present embodiment uses wound cells to realize the short blade battery structure. Due to the high molding efficiency of the wound cells, the manufacturing efficiency of the short blade battery can be significantly improved. On the other hand, compared with the prior art that uses a single stacked cell to realize the short blade battery structure, the present embodiment realizes the short blade battery structure by connecting a plurality of wound cells in parallel. Due to the high manufacturing pass rate of the wound cells, when the short blade battery is designed to have a large capacity, the problem of the increase in the number of stacked layers and the size of the pole pieces can be avoided. On the other hand, the problem of the positive electrode sheet and the negative electrode sheet being easily misaligned and sliding is solved, thereby reducing the risk of the lithium-ion battery being scrapped due to a short circuit, so as to significantly improve the manufacturing yield of the short blade battery; on the other hand, for the large-capacity short blade battery, compared with the prior art of pre-welding all the positive electrode ears or negative electrode ears of the stacked battery cell and then performing laser welding of the adapter sheet, the present embodiment welds the positive electrode ears of a plurality of wound battery cells to the positive electrode connecting component, and welds the negative electrode ears of a plurality of wound battery cells to the negative electrode connecting component, so that the number of electrode ear layers and the total thickness in a single laser welding can be reduced, thereby reducing the risk of laser cold welding. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The drawings constituting part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation on the present invention. In the drawings:

[0018] Figure 1 A schematic structural diagram of an embodiment of a wound battery cell of the utility model is shown;

[0019] Figure 2 Shows Figure 1 A schematic diagram of the structure of the positive electrode ear and the negative electrode ear of the wound battery cell after pre-welding;

[0020] Figure 3 A schematic structural diagram of a first embodiment of a lithium-ion battery of the present utility model is shown (wherein the housing is not shown);

[0021] Figure 4 Shows Figure 3 Schematic diagram of a partial structure of a lithium-ion battery;

[0022] Figure 5 Shows Figure 4 A schematic structural diagram of a partial structure of a lithium-ion battery in another direction;

[0023] Figure 6 Shows Figure 3 A schematic structural diagram of a positive electrode ear and a positive electrode connecting member of a lithium-ion battery after welding;

[0024] Figure 7 A schematic structural diagram of a second embodiment of a lithium-ion battery of the utility model is shown (wherein the housing is not shown);

[0025] Figure 8 Shows Figure 7 A schematic structural diagram of a positive electrode ear and a positive electrode connecting member of a lithium-ion battery after welding;

[0026] Fig. 9 The structure diagram of the third embodiment of the lithium-ion battery of the present utility model is shown (wherein the housing is not shown);

[0027] Fig.10 Shows Fig. 9 A front view of a lithium-ion battery;

[0028] Fig.11 Shows Fig. 9 A top view of a lithium-ion battery;

[0029] Fig.12 Shows Fig. 9 A schematic structural diagram of a positive electrode ear and a positive electrode connecting member of a lithium-ion battery after welding;

[0030] Fig.13 Another structural schematic diagram of the third embodiment of the lithium-ion battery of the utility model is shown (wherein the housing is not shown);

[0031] Fig.14 A schematic structural diagram of an embodiment of a lithium-ion battery of the utility model is shown (wherein an insulating film is shown);

[0032] Fig.15 A schematic structural diagram of an embodiment of a lithium-ion battery of the utility model is shown (wherein a first half shell is shown);

[0033] Fig.16 A schematic structural diagram of an embodiment of a lithium-ion battery of the utility model is shown (wherein a housing is shown).

[0034] The above drawings include the following reference numerals:

[0035] 11. winding core body; 12. positive ear; 13. negative ear; 21. positive cover; 22. positive column; 23. explosion-proof valve; 24. positive connecting member; 241. first positive connecting piece; 242. second positive connecting piece; 25. insulating gasket; 26. positive avoidance groove; 31. negative cover; 32. negative column; 33. injection hole; 34. negative connecting member; 341. first negative connecting piece; 342. second negative connecting piece; 40. insulating film; 50. first half shell; 60. second half shell. DETAILED DESCRIPTION

[0036] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present utility model will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0037] It should be noted that the lithium-ion battery in the embodiment of the present utility model is a short blade battery.

[0038] like Figures 1 to 16 As shown, an embodiment of the utility model provides a lithium-ion battery. The lithium-ion battery includes a mounting shell, a plurality of wound cells, a positive electrode connecting member 24 and a negative electrode connecting member 34. Among them, a positive electrode column 22 and a negative electrode column 32 are provided on the mounting shell; a plurality of wound cells are arranged in rows along the X direction and / or in columns along the Z direction in the mounting shell, and each wound cell includes a winding core body 11, a positive electrode ear 12 and a negative electrode ear 13; the positive electrode connecting member 24 is connected to the positive electrode column 22, and the positive electrode connecting member 24 is connected to the plurality of positive electrode ears 12 and is located on the same side of the winding core body 11; the negative electrode connecting member 34 is connected to the negative electrode column 32, and the negative electrode connecting member 34 is connected to the plurality of negative electrode ears 13 and is located on the same side of the winding core body 11, and the X direction and the Z direction are arranged at an angle.

[0039] In the above technical scheme, on the one hand, compared with the prior art that uses stacked cells to realize the short blade battery structure, this embodiment uses wound cells to realize the short blade battery structure. Due to the high molding efficiency of the wound cells, the manufacturing efficiency of the short blade battery can be significantly improved. On the other hand, compared with the prior art that uses a single stacked cell to realize the short blade battery structure, this embodiment realizes the short blade battery structure by connecting a plurality of wound cells in parallel. Due to the high manufacturing qualification rate of the wound cells, when the design capacity of the short blade battery is large, the positive electrode sheet caused by the increase in the number of stacked layers and the size of the electrode sheet can be avoided. and the problem of easy dislocation and sliding of negative electrode sheets, thereby reducing the risk of lithium-ion batteries being scrapped due to short circuits, and significantly improving the manufacturing yield of short blade batteries; on the other hand, for large-capacity short blade batteries, compared with the prior art of pre-welding all the positive or negative ears of the stacked battery cells and then performing laser welding of the adapter sheets, the present embodiment welds the positive ears 12 of a plurality of wound battery cells to the positive connecting member 24, and welds the negative ears 13 of a plurality of wound battery cells to the negative connecting member 34, respectively. In this way, the number of ear layers and the total thickness during a single laser welding can be reduced, thereby reducing the risk of laser cold welding.

[0040] Furthermore, the present embodiment only needs to use a number of identical wound battery cells, and through different parallel connection methods, any even number of wound battery cells can be connected in parallel, thereby improving the process adaptability.

[0041] Specifically, Figure 1As shown, in the embodiment of the present invention, the wound battery cell is formed by unidirectionally winding a four-layer unit formed by a separator, a positive electrode sheet, a separator, and a negative electrode sheet.

[0042] Specifically, in the embodiment of the present utility model, Figure 1 The multi-layer positive electrode ears and multi-layer negative electrode ears are pre-welded respectively, the purpose is to weld the multi-layer electrode ears together to prevent the electrode ears from being fluffy, so as to form positive electrode ears 12 and negative electrode ears 13 respectively, which is convenient for subsequent battery cell assembly. Preferably, the electrode ears can be pre-welded by ultrasonic welding.

[0043] Specifically, in the embodiment of the present invention, along the Y direction, the positive electrode ear portion 12 and the negative electrode ear portion 13 are respectively connected to the two sides of the winding core body 11 , and are arranged at an angle between each other in the X direction, the Y direction and the Z direction.

[0044] It should be noted that in the embodiments of the present invention, Figure 3 As shown, the X direction is the row arrangement direction of the multiple wound battery cells, and is also the length direction of the wound battery cells; the Y direction is the width direction of the wound battery cells; and the Z direction is the thickness direction of the wound battery cells, wherein the X direction, the Y direction, and the Z direction are arranged perpendicularly to each other.

[0045] like Figures 3 to 13 As shown, in the embodiment of the utility model, along the X direction, the positive electrode column 22 and the negative electrode column 32 are respectively located on opposite sides of the mounting shell; the positive electrode connecting member 24 includes a first positive connecting piece 241 and a second positive connecting piece 242 that are connected and arranged at an angle, a plurality of positive electrode ears 12 are connected to the first positive connecting piece 241, and the positive electrode column 22 is connected to the second positive connecting piece 242; the negative electrode connecting member 34 includes a first negative connecting piece 341 and a second negative connecting piece 342 that are connected and arranged at an angle, a plurality of negative electrode ears 13 are connected to the first negative connecting piece 341, and the negative electrode column 32 is connected to the second negative connecting piece 342.

[0046] Through the above arrangement, multiple positive ears 12 can be connected to the positive electrode column 22 through the positive electrode connecting member 24, and multiple negative ears 13 can be connected to the negative electrode column 32 through the negative electrode connecting member 34, so that multiple wound battery cells can be connected in parallel; and multiple positive ears 12 are respectively connected to the first positive connecting sheet 241, and multiple negative ears 13 are respectively connected to the first negative connecting sheet 341, which can reduce the number of ear layers and the total thickness during a single laser welding, thereby reducing the risk of laser cold welding.

[0047] In one embodiment, in the X direction, the positive electrode column 22 and the negative electrode column 32 may be disposed on the same side of the mounting shell.

[0048] Preferably, in the embodiment of the present invention, the first positive connecting piece 241 and the second positive connecting piece 242 are arranged perpendicular to each other, and the first negative connecting piece 341 and the second negative connecting piece 342 are arranged perpendicular to each other.

[0049] like Figure 4 and Figure 5 As shown, in the embodiment of the utility model, the mounting shell includes: a shell; a positive electrode cover plate 21; a negative electrode cover plate 31, along the X direction, the positive electrode cover plate 21 and the negative electrode cover plate 31 are respectively connected to the two sides of the shell, and the positive electrode cover plate 21 is provided with a positive electrode column 22, and the negative electrode cover plate 31 is provided with a negative electrode column 32. In this way, multiple wound battery cells can be installed in the shell first, and then the positive electrode cover plate 21 and the negative electrode cover plate 31 are covered on the shell, so as to facilitate the installation of multiple wound battery cells.

[0050] Preferably, in the embodiment of the present invention, the positive electrode cover plate 21 and the negative electrode cover plate 31 are welded to both ends of the shell respectively.

[0051] Specifically, in the embodiment of the utility model, an explosion-proof valve 23 is provided on the positive electrode cover plate 21 , and a liquid injection hole 33 is provided on the negative electrode cover plate 31 .

[0052] Specifically, in the embodiment of the present invention, the positive electrode cover plate 21, the negative electrode cover plate 31, the positive electrode column 22, the positive electrode connecting member 24, and the positive electrode ear 12 are all made of aluminum; the negative electrode column 32, the negative electrode connecting member 34, and the negative electrode ear 13 are all made of copper.

[0053] like Fig.15 and Fig.16 As shown, in the embodiment of the present invention, the shell includes a first half shell 50 and a second half shell 60 connected to each other, and the first half shell 50 and the second half shell 60 are respectively arranged on both sides of the plurality of wound battery cells.

[0054] Through the above arrangement, the first half shell 50 is buckled into Fig.15 On the parallel double-wound battery cell shown, Fig.16 As shown, the second half shell 60 is then buckled, so that multiple wound battery cells can be easily installed.

[0055] Preferably, in the embodiment of the present invention, the first half shell 50 and the second half shell 60 are arranged along the Y direction.

[0056] Preferably, in an embodiment of the present invention, the housing is made of aluminum.

[0057] like Fig.16As shown, in the embodiment of the utility model, a limiting member is provided on the first half shell 50, and a limiting groove is provided on the second half shell 60, and the limiting groove and the limiting member are matched in limiting position. In this way, the first half shell 50 and the second half shell 60 are butted against each other through the limiting groove and the limiting member that are matched in limiting position, so that it is convenient to weld the inner wall of the limiting groove and the limiting member by laser.

[0058] like Fig.14 As shown, in the embodiment of the present invention, an insulating film 40 is provided between the multiple wound battery cells and the inner wall of the shell. The insulating film 40 is wound around the winding core body 11 of the multiple wound battery cells as a whole, which can prevent surface scratches when the subsequent wound battery cells are put into the shell.

[0059] like Figure 5 As shown, in the embodiment of the utility model, an insulating gasket 25 is provided between the positive electrode column 22 and the positive electrode cover plate 21, and an insulating gasket 25 is provided between the negative electrode column 32 and the negative electrode cover plate 31. In this way, the positive electrode column 22 can be isolated and contacted with the positive electrode cover plate 21 through the insulating gasket 25, and the negative electrode column 32 can be isolated and contacted with the negative electrode cover plate 31 through the insulating gasket 25.

[0060] Specifically, in an embodiment of the utility model, the insulating gasket 25 includes a substrate and a sleeve connected to the substrate, the sleeve is located between the positive electrode column 22 (negative electrode column 32) and the positive electrode cover plate 21 (negative electrode cover plate 31), and the substrate is located between the winding core body 11 and the positive electrode cover plate 21 (negative electrode cover plate 31).

[0061] Embodiment 1

[0062] like Figures 3 to 6 As shown, in the first embodiment of the present invention, a plurality of wound cells are arranged in sequence along the X direction, each positive ear portion 12 is bent and welded to the first positive connecting piece 241, and each negative ear portion 13 is bent and welded to the first negative connecting piece 341. In this way, a plurality of wound cells can be arranged in a row, and the above structure is simple and easy to process.

[0063] like Figure 3 As shown, in the first embodiment of the utility model, two identical wound battery cells are placed side by side along the X direction, and then the first positive connecting piece 241 is placed above the positive ear 12, and the first negative connecting piece 341 is placed above the negative ear 13, and then the pre-welded positive ear 12 is bent and laser welded to the first positive connecting piece 241, and the pre-welded negative ear 13 is bent and laser welded to the first negative connecting piece 341.

[0064] Embodiment 2

[0065] like Figure 7 and Figure 8As shown, the difference between the second embodiment of the present invention and the first embodiment is that a plurality of wound cells are arranged in rows and columns along the X direction and the Z direction, each positive electrode ear 12 is bent and welded to the first positive connecting piece 241, and each negative electrode ear 13 is bent and welded to the first negative connecting piece 341. In this way, a plurality of wound cells can be connected in parallel.

[0066] like Figure 8 As shown, in the second embodiment of the present invention, along the Z direction, the bending directions of the negative ear portions 13 of two adjacent wound cells are the same, the first positive connecting piece 241 is provided with a positive avoidance groove 26, and the negative ear portion 13 of one of the two adjacent wound cells passes through the positive avoidance groove 26; along the Z direction, the bending directions of the positive ear portions 12 of two adjacent wound cells are the same, the first negative connecting piece 341 is provided with a negative avoidance groove, and the negative ear portion 13 of one of the two adjacent wound cells passes through the negative avoidance groove. In this way, it is convenient to fix the positive ear portion 12 and the negative ear portion 13 on the first positive connecting piece 241 and the first negative connecting piece 341 respectively.

[0067] Specifically, in the second embodiment of the present invention, four identical wound cells are wound according to Figure 7 The four positive ear portions 12 are arranged as shown, and the four negative ear portions 13 are located on the same side, and the four positive ear portions 13 are located on the other side. The positive ear portions 12 and the negative ear portions 13 after pre-welding are assembled with the positive electrode connecting member 24 and the negative electrode connecting member 34 respectively, and finally installed. Figure 8 As shown, the positive electrode ear portion 12 and the negative electrode ear portion 13 are bent and welded to the corresponding positive electrode connecting member 24 and the negative electrode connecting member 34 by laser.

[0068] Embodiment 3

[0069] like Figures 9 to 13 As shown, the difference between the third embodiment of the present invention and the second embodiment is that the relative position of the positive ear 12 in the Z direction is different, and the relative position of the negative ear 13 in the Z direction is different; along the Z direction, the bending directions of the negative ear 13 of two adjacent wound cells are opposite; along the Z direction, the bending directions of the positive ear 12 of two adjacent wound cells are opposite. In this way, it is convenient to fix the positive ear 12 and the negative ear 13 on the first positive connecting sheet 241 and the first negative connecting sheet 341 respectively.

[0070] Specifically, in the embodiment of the utility model, the positive electrode ears 12 of two adjacent wound battery cells are located on opposite sides of the positive electrode connecting member 24, and the two positive electrode ears 12 are bent toward each other on the positive electrode connecting member 24 from the two sides of the positive electrode connecting member 24, so there is no need to set the positive electrode avoidance groove 26 on the positive electrode connecting member 24; similarly, there is no need to set the negative electrode avoidance groove on the negative electrode connecting member 34.

[0071] like Figures 9 to 12 As shown, in the third embodiment of the present invention, four identical wound battery cells have positive ears 12 located on the same side and negative ears 13 located on the other side. After pre-welding, the positive ears 12 and negative ears 13 are assembled with the positive connecting member 24 and the negative connecting member 34 respectively. Finally, the positive ears 12 and the negative ears 13 are bent and laser welded to the positive connecting member 24 and the negative connecting member 34 respectively.

[0072] In the third embodiment of the present invention, six identical wound cells are wound Fig.13 The positive electrode ears 12 are arranged in the same way as shown in the figure, and the negative electrode ears 13 are located on the other side. The positive electrode ears 12 and the negative electrode ears 13 after pre-welding are assembled with the positive electrode connecting member 24 and the negative electrode connecting member 34 respectively. Finally, the positive electrode ears 12 and the negative electrode ears 13 are bent and laser welded to the positive electrode connecting member 24 and the negative electrode connecting member 34 respectively.

[0073] The other structures of the third embodiment of the present invention are the same as those of the second embodiment, and will not be described again here.

[0074] It should be noted that in the embodiment of the present invention, for the case where multiple wound cells (number ≥ 4) are connected in parallel, the number of rows of the X-direction wound cells and the number of layers of the Z-direction wound cells are not limited. For example, when 6 wound cells are connected in parallel, Fig.13 As shown, the cores are stacked in three rows in the X direction and in two layers in the Z direction, or the cores are stacked in two rows in the X direction and in three layers in the Z direction.

[0075] It should be noted that in the embodiment of the present invention, the explosion-proof valve 23 can also be set on the negative cover plate 31, and the injection hole 33 can also be set on the positive cover plate 21; the explosion-proof valve 23 and the injection hole 33 can also be set on the negative cover plate 31 or the positive cover plate 21 at the same time.

[0076] The utility model uses a number of wound cells connected in parallel to realize the short blade battery structure. By setting different parallel forms, any even-numbered wound cells can be connected in parallel, and the process adaptability is strong. In addition, the utility model changes the single aluminum shell of the traditional short blade battery into two aluminum shells, and changes the laser welding of all pole ears at the same time into laser welding of several multi-layer pole ears (positive pole ears or negative pole ears) separately, which solves the problem of wound battery cells entering the shell and welding cold welds when the positive and negative poles are located at the two ends.

[0077] From the above description, it can be seen that the above-mentioned embodiments of the utility model achieve the following technical effects: on the one hand, compared with the prior art that uses stacked battery cells to realize the short blade battery structure, the present embodiment uses wound battery cells to realize the short blade battery structure. Due to the high molding efficiency of the wound battery cells, the manufacturing efficiency of the short blade battery can be significantly improved. On the other hand, compared with the prior art that uses a single stacked battery cell to realize the short blade battery structure, the present embodiment realizes the short blade battery structure by connecting a plurality of wound battery cells in parallel. Due to the high manufacturing qualification rate of the wound battery cells, when the short blade battery is designed to have a large capacity, it can avoid the problem of The problem of the positive and negative electrodes being easily misaligned and slipped due to the increase in the number of stacking layers and the size of the electrodes can be solved, thereby reducing the risk of lithium-ion batteries being scrapped due to short circuits, so as to significantly improve the manufacturing yield of short blade batteries; on the other hand, for large-capacity short blade batteries, compared with the prior art of pre-welding all the positive or negative electrodes of the stacked battery cells and then laser welding the adapter sheets, in this embodiment, the positive electrodes of multiple wound battery cells are respectively welded to the positive electrode connecting components, and the negative electrodes of multiple wound battery cells are respectively welded to the negative electrode connecting components. In this way, the number of electrode ear layers and the total thickness can be reduced during a single laser welding, thereby reducing the risk of laser cold welding.

[0078] The above description is only the preferred embodiment of the utility model, and is not intended to limit the utility model. For those skilled in the art, the utility model can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model shall be included in the protection scope of the utility model.

Claims

1. A lithium ion battery, characterized in that: include: A mounting shell, wherein a positive pole (22) and a negative pole (32) are provided on the mounting shell; A plurality of wound battery cells are arranged in rows along the X direction and / or in columns along the Z direction in the installation shell, each of the wound battery cells comprising a wound core body (11), a positive electrode ear portion (12) and a negative electrode ear portion (13); A positive electrode connecting member (24) connected to the positive electrode column (22), the positive electrode connecting member (24) connected to the plurality of positive electrode ears (12) and located on the same side of the winding core body (11); A negative electrode connecting member (34) is connected to the negative electrode column (32). The negative electrode connecting member (34) is connected to a plurality of negative electrode ears (13) and is located on the same side of the winding core body (11). The X direction and the Z direction are arranged at an angle.

2. The lithium-ion battery according to claim 1, characterized in that Along the X direction, the positive pole (22) and the negative pole (32) are respectively located on opposite sides of the mounting shell; The positive electrode connecting member (24) comprises a first positive connecting piece (241) and a second positive connecting piece (242) which are connected and arranged at an angle, a plurality of positive electrode ears (12) are connected to the first positive connecting piece (241), and the positive electrode column (22) is connected to the second positive connecting piece (242); The negative electrode connecting member (34) comprises a first negative connecting piece (341) and a second negative connecting piece (342) which are connected and arranged at an angle, a plurality of negative electrode ears (13) are connected to the first negative connecting piece (341), and the negative electrode column (32) is connected to the second negative connecting piece (342).

3. The lithium-ion battery according to claim 2, characterized in that: The plurality of wound battery cells are arranged in sequence along the X direction, each positive electrode ear (12) is bent and welded to the first positive connecting piece (241), and each negative electrode ear (13) is bent and welded to the first negative connecting piece (341).

4. The lithium-ion battery according to claim 2, characterized in that: The plurality of wound battery cells are arranged in rows and columns along the X direction and the Z direction, each positive electrode ear (12) is bent and welded to the first positive connecting piece (241), and each negative electrode ear (13) is bent and welded to the first negative connecting piece (341).

5. The lithium-ion battery according to claim 4, characterized in that: Along the Z direction, the bending directions of the negative electrode ears (13) of two adjacent wound battery cells are the same, a positive electrode avoidance groove (26) is provided on the first positive connecting sheet (241), and the negative electrode ear (13) of one of the two adjacent wound battery cells passes through the positive electrode avoidance groove (26); Along the Z direction, the positive electrode ears (12) of two adjacent wound battery cells have the same bending direction, a negative electrode avoidance groove is provided on the first negative connecting sheet (341), and the negative electrode ear (13) of one of the two adjacent wound battery cells passes through the negative electrode avoidance groove.

6. The lithium-ion battery according to claim 4, characterized in that: Along the Z direction, the bending directions of the negative electrode ears (13) of two adjacent wound battery cells are opposite; Along the Z direction, the bending directions of the positive electrode ears (12) of two adjacent wound battery cells are opposite.

7. The lithium ion battery according to any one of claims 1 to 6, characterized in that The mounting shell comprises: case; A positive electrode cover plate (21); A negative electrode cover plate (31), along the X direction, the positive electrode cover plate (21) and the negative electrode cover plate (31) are respectively connected to two sides of the shell, the positive electrode cover plate (21) is provided with the positive electrode column (22), and the negative electrode cover plate (31) is provided with the negative electrode column (32).

8. The lithium-ion battery according to claim 7, characterized in that: The shell comprises a first half shell (50) and a second half shell (60) which are connected to each other, and the first half shell (50) and the second half shell (60) are respectively arranged on two sides of the plurality of wound battery cells.

9. The lithium-ion battery according to claim 8, characterized in that: The first half shell (50) is provided with a limiting component, and the second half shell (60) is provided with a limiting groove, and the limiting groove and the limiting component are in limiting cooperation.

10. The lithium ion battery according to claim 7, characterized in that: An insulating film (40) is provided between the plurality of wound battery cells and the inner wall of the shell; and / or, An insulating gasket (25) is provided between the positive electrode column (22) and the positive electrode cover plate (21), and an insulating gasket (25) is provided between the negative electrode column (32) and the negative electrode cover plate (31).

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