Full-tab large cylindrical sodium ion battery for improving liquid injection

Abstract

The utility model belongs to the field of large cylindrical sodium ion batteries, and particularly relates to a full-tab large cylindrical sodium ion battery for improving liquid injection, which adopts the following scheme that the full-tab large cylindrical sodium ion battery comprises a shell, a roll core is fixedly assembled on the inner side of the shell, a negative electrode cover plate is fixedly assembled at the bottom of the shell, and a sealing plate is fixedly assembled at the bottom of the negative electrode cover plate; the winding core is formed by winding a pole piece and a diaphragm, the positive collector plate is welded with the positive end of the winding core, and the winding core comprises a winding core outer ring tab-free area, a winding core inner ring tab-free area and a full tab area. The contact area of the pole piece and the electrolyte is increased, the liquid injection process is improved, the roll core can absorb the liquid in a short time, the risk caused by poor liquid absorption is better improved, and compared with traditional mechanical rubbing, the compactness of the pole lugs stacked through laser die cutting and ultrasonic rubbing is low, and absorption of the pole piece to the electrolyte is also facilitated.

Description

Technical Field

[0001] The utility model relates to the technical field of large cylindrical sodium ion batteries, in particular to a full-pole lug large cylindrical sodium ion battery with improved liquid injection. Background Art

[0002] In recent years, the development trend of sodium-ion batteries has been rapid, and the demand for sodium-ion batteries in the market has been increasing. The mainstream direction of existing large cylindrical sodium batteries all adopts a full-ear design, and the positive and negative ear ends are formed by laser die-cutting, winding and stacking. The full-ear battery effectively reduces the internal resistance and thus reduces the temperature rise of the battery, and improves the cycle and service life of the battery. However, the disadvantage of the full-ear battery is that the flattened ears at both ends block the pole pieces, which affects the liquid absorption of the winding core. High pressure and long time are required for liquid injection, and the pole pieces will not absorb liquid well, resulting in white strips. The abnormality causes the increase of the battery internal resistance and the risk of poor circulation. Therefore, the utility model proposes a large cylindrical sodium-ion battery with full-ear ears that improves liquid injection to solve the above problems. Utility Model Content

[0003] Based on the background technology, the disadvantage of full-tab batteries is that the tabs at both ends are flattened to block the pole pieces, which affects the liquid absorption of the core. High pressure and long time are required for liquid injection, and poor liquid absorption of the pole pieces will occur, resulting in abnormal white strips and increased internal resistance of the battery and risk of poor circulation. The utility model proposes a full-tab large cylindrical sodium-ion battery with improved liquid injection.

[0004] The utility model provides a large cylindrical sodium ion battery with full-pole ears and improved liquid injection, comprising a shell, a winding core is fixedly mounted on the inner side of the shell, a negative electrode cover is fixedly mounted on the bottom of the shell, a sealing plate is fixedly mounted on the bottom of the negative electrode cover, the winding core is wound by winding a pole piece and a diaphragm, a positive current collecting disc is welded to the positive end of the winding core, and a negative current collecting disc is welded to the negative end of the winding core.

[0005] Preferably, the winding core comprises an outer ring region without tabs, an inner ring region without tabs and a full tab region.

[0006] Preferably, the positive collecting plate and the negative collecting plate are made of aluminum.

[0007] Furthermore, aluminum is lightweight and has good ductility, electrical conductivity, thermal conductivity, heat resistance, and radiation resistance.

[0008] Preferably, the negative electrode cover plate is provided with explosion-proof notches.

[0009] Furthermore, when the internal pressure of the battery increases, the marks will crack to release the pressure and prevent the battery from exploding.

[0010] The beneficial effects of the utility model are:

[0011] The pole piece and the pole ear are laser die-cut, and then flattened in stacking form after winding. Compared with the traditional mechanical flattening and ultrasonic flattening of the pole ear, this solution is more beautiful and does not produce metal powder, avoiding the risk of large self-discharge and internal short circuit; the pole ear is die-cut, and the pole ear is stacked in an orderly manner with a gap between the pole ears. The end face density is lower than the end face density of the traditional flattening method, and the effect of the area with the pole ear absorbing electrolyte is also better than the traditional flattening method;

[0012] The utility model die-cuts a part of the pole ears at the entry end and the tail end of the pole piece, and forms inner and outer circle pole ear-free areas after winding, thereby increasing the contact area between the pole piece and the electrolyte and improving the liquid injection process. The winding core can absorb liquid in a short time to better improve the risk caused by poor liquid absorption. The pole ears after laser die-cutting and stacking are less dense than those flattened by traditional mechanical and ultrasonic flattening, which also helps the pole piece to absorb the electrolyte. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 A schematic diagram of a top view of a structural winding core of a large cylindrical sodium-ion battery with full-electrode tabs and improved liquid injection proposed by the utility model;

[0014] Figure 2 This is a schematic diagram of the front view of the structural winding core of a large cylindrical sodium-ion battery with full-electrode tabs and improved liquid injection proposed by the utility model;

[0015] Figure 3 A schematic top view of a positive current collecting plate of a large cylindrical sodium ion battery with full-electrode tabs and improved liquid injection proposed by the utility model;

[0016] Figure 4 This is a schematic diagram of the front view of the positive current collecting plate of a large cylindrical sodium ion battery with full-pole ears and improved liquid injection proposed by the utility model;

[0017] Figure 5 A schematic bottom view of a negative current collecting plate of a large cylindrical sodium ion battery with full-electrode tabs and improved liquid injection proposed by the utility model;

[0018] Figure 6 It is a schematic diagram of the main view of the negative current collecting plate of a large cylindrical sodium ion battery with full-pole ears and improved liquid injection proposed by the utility model;

[0019] Figure 7 This is a schematic diagram of the main structural shell of a large cylindrical sodium-ion battery with full-electrode tabs and improved liquid injection proposed by the utility model;

[0020] Figure 8 It is a schematic diagram of the main view of the positive electrode sheet in the structure of the large cylindrical sodium ion battery with full-electrode tabs and improved liquid injection proposed by the utility model;

[0021] Fig. 9It is a schematic diagram of the main view of the negative electrode sheet in the structure electrode sheet of a large cylindrical sodium ion battery with full-electrode tabs and improved liquid injection proposed by the utility model;

[0022] Fig.10 The utility model proposes a structural attachment of a large cylindrical sodium ion battery with full-pole ears and improved liquid injection. Figure 2 Middle A is an enlarged schematic diagram;

[0023] Fig.11 The utility model proposes a structural attachment of a large cylindrical sodium ion battery with full-pole ears and improved liquid injection. Figure 7 Middle B is an enlarged schematic diagram;

[0024] Fig.12 The utility model proposes a structural attachment of a large cylindrical sodium ion battery with full-pole ears and improved liquid injection. Figure 7 Middle C is an enlarged schematic diagram;

[0025] Fig.13 The utility model proposes a structural attachment of a large cylindrical sodium ion battery with full-pole ears and improved liquid injection. Figure 7 Middle D is an enlarged schematic diagram;

[0026] Fig.14 The utility model proposes a structural attachment of a large cylindrical sodium ion battery with full-pole ears and improved liquid injection. Figure 8 Middle E is an enlarged schematic diagram;

[0027] Fig.15 The utility model proposes a structural attachment of a large cylindrical sodium ion battery with full-pole ears and improved liquid injection. Fig. 9 Middle F is the enlarged schematic diagram.

[0028] In the figure: 1. The outer ring of the winding core has no tab area; 2. The inner ring of the winding core has no tab area; 3. The full tab area; 4. The positive current collecting plate; 5. The negative current collecting plate; 6. The pole piece; 7. The winding core; 8. The shell; 9. The negative electrode cover plate; 10. The sealing plate. DETAILED DESCRIPTION

[0029] The present invention will be further explained below in conjunction with specific embodiments.

[0030] refer to Figure 1-8 In this embodiment, a large cylindrical sodium-ion battery with full-ears and improved liquid injection is proposed, including a shell 8, a winding core 7 is fixedly installed on the inner side of the shell 8, a negative electrode cover plate 9 is fixedly installed on the bottom of the shell 8, a sealing plate 10 is fixedly installed on the bottom of the negative electrode cover plate 9, the winding core 7 is wound by a pole piece 6 and a diaphragm, a positive current collecting disc 4 is welded to the positive end of the winding core 7, and a negative current collecting disc 5 is welded to the negative end of the winding core 7.

[0031] Preferably, the winding core 7 includes an outer ring of the winding core without a tab region 1, an inner ring of the winding core without a tab region 2 and a full tab region 3.

[0032] Preferably, the positive collecting plate 4 and the negative collecting plate 5 are made of aluminum, which is light in weight and has good ductility, electrical conductivity, thermal conductivity, heat resistance and radiation resistance.

[0033] Preferably, the negative electrode cover plate 9 is provided with an explosion-proof notch, and when the internal pressure of the battery increases, the notch cracks to release pressure and prevent the battery from exploding.

[0034] Working principle: The electrode sheet 6 includes a positive electrode sheet and a negative electrode sheet. The electrode ears of the electrode sheet 6 are cut into parallelogram-shaped ears with equal height and equal spacing by laser cutting. A part of the electrode ear-free area A and B is cut off at the winding end and the winding end. The positive and negative electrode sheets and the separator are wound into a winding core 7. Figure 1 The two end surfaces form a core outer ring without pole ear area 1, a core inner ring without pole ear area 2, and a full pole ear area 3. The positive collector plate 4 is welded to the positive end of the core 7, the positive collector plate 4 fan-shaped area is welded to the full pole ear area 3 of the core 7, the negative collector plate 5 is welded to the negative end of the core 7, the negative collector plate 5 fan-shaped area is welded to the full pole ear area 3 of the core 7, the positive collector plate 4 is ultrasonically point-bottom welded to the positive pole column, the negative collector plate 5 is welded to the shell wall, the negative cover plate 9 is welded to the steel shell, and the battery is injected through the injection hole. After the injection is qualified, the injection hole is welded , the total width of the positive electrode sheet is 77mm, the width of the material area is 68mm, and the width of the foil is 9mm; the total width of the negative electrode sheet is 78.5mm, the width of the material area is 71mm, and the width of the foil is 7.5mm; the width of the diaphragm is 74mm; the total height of the winding core 7 after the winding tabs are stacked and flattened is 74.5mm, the length of the positive electrode sheet is 5282mm, the length A of the non-polar tab cut by the die at the entry end is 804mm, and the length B of the non-polar tab cut by the die at the winding end is 1600mm; the cutting tab size a is 5mm, b is 6mm, c is 1mm, d is 80°, and the negative electrode sheet length is 5282mm. The length of the non-polar ear cut by the die at the entry end is 749mm, and the length of the non-polar ear cut by the die at the winding end is 1540mm; the cutting polar ear size a is 5mm, b is 6mm, c is 1mm, and d is 80°. After the polar ear is stacked on the core 7, the polar ear end surface forms the outer ring non-polar ear area, the inner ring non-polar ear area, and the full polar ear area 3. The positive collector plate is welded to the positive full polar ear area 3 of the core 7, and the negative collector plate 5 is welded to the negative polar ear area of ​​the core 7. The positive terminal surface is wrapped with high-temperature tape, and the positive collector plate is made of a thickness of 0. 4mm material 1060-O outer diameter φ45mm aluminum disc, set 6 sector-shaped welding areas, the negative current collector disc uses 0.4mm thickness material 1060-O outer diameter φ45mm aluminum disc, set 6 sector-shaped welding areas, the winding core 7 after welding the current collector disc is put into the shell, the positive current collector disc 4 and the positive electrode rivet are ultrasonically point-bottom welded, the negative current collector disc 5 and the shell wall are laser welded, the negative cover plate 9 and the steel shell are laser welded, the battery is injected through the injection hole of the negative cover plate 9, and the injection hole is laser welded and sealed after the injection process is qualified.

[0035] The injection effect and process were compared by mechanically flattening the full-tab core, laser die-cutting the full-tab core, and laser die-cutting the inner and outer tab core. The experimental data are as follows:

[0036] Core end face Vacuum degree Pressurization pressure Core wetting effect Process time Laser die-cutting of inner and outer tab cores -0.09~-0.1Mpa ≥0.8Mpa No white strip 63min Laser die-cut full-ear roll core -0.09~-0.1Mpa ≥0.8Mpa No white strip 81min Mechanically flattened full-ear winding core -0.09~-0.1Mpa ≥0.8Mpa No white strip 90min

[0037] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes within the technical scope disclosed by the present invention according to the technical scheme and the utility model concept of the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A large cylindrical sodium ion battery with full-tab lugs and improved liquid injection, comprising a housing (8), characterized in that: A winding core (7) is fixedly mounted on the inner side of the shell (8), a negative electrode cover plate (9) is fixedly mounted on the bottom of the shell (8), a sealing plate (10) is fixedly mounted on the bottom of the negative electrode cover plate (9), the winding core (7) is wound by winding the electrode sheet (6) and the diaphragm, the positive current collecting disc (4) is welded to the positive end of the winding core (7), and the negative current collecting disc (5) is welded to the negative end of the winding core (7).

2. A large cylindrical sodium ion battery with full-tabs and improved liquid injection according to claim 1, characterized in that: The winding core (7) comprises a winding core outer ring area without a tab (1), a winding core inner ring area without a tab (2) and a full tab area (3).

3. A large cylindrical sodium ion battery with full-tabs and improved liquid injection according to claim 1, characterized in that: The positive current collecting plate (4) and the negative current collecting plate (5) are made of aluminum.

4. The large cylindrical sodium ion battery with improved liquid injection and full-tab structure according to claim 1, characterized in that: The negative electrode cover plate (9) is provided with explosion-proof notches.

Images