Lithium ion battery cell pack structure and forming method thereof

Abstract

The application belongs to the technical field of lithium ion battery core package structure, and also relates to a forming method of the lithium ion battery core package structure. A plurality of negative electrode slurry layers (106) are printed on the upper surface and the lower surface of a negative electrode sheet substrate (109) according to intervals, a plurality of positive electrode slurry layers (206) are printed on the upper surface and the lower surface of a positive electrode sheet substrate (209) according to intervals, a negative electrode main tab (107) is arranged on the upper surface of the negative electrode sheet substrate (109), and a negative electrode auxiliary tab (108) is arranged at a negative electrode substrate interval position (102) between the negative electrode slurry layers (106) on the upper surface of the negative electrode sheet substrate (109). A positive electrode main tab (207) is arranged on the upper surface of the positive electrode sheet substrate (209), and a positive electrode auxiliary tab (208) is arranged at a positive electrode substrate interval position (202) between the positive electrode slurry layers (206). The lithium ion battery core package structure can greatly improve the charge-discharge rate of the winding type battery core, and improve the overall performance and service life of the battery.

Description

Technical Field

[0001] This invention belongs to the field of lithium-ion battery technology, and more specifically, relates to a lithium-ion battery cell pack structure. This invention also relates to a method for forming a lithium-ion battery cell pack structure. Background Technology

[0002] With the advent of the information age, intelligent electronic devices have brought tremendous convenience to people's lives and work. Portable devices are the most typical examples, such as drones and handheld power tools. However, these devices all share a common characteristic: they require high-rate charging and discharging. Recently, research on these high-rate batteries has increased significantly and has become a hot research area.

[0003] Currently, battery cell pack structure designs mainly fall into two categories: multi-tab winding and stacking. However, both have drawbacks. For example, multi-tab winding can experience rebound after die-cutting the tabs, leading to tab welding failure. Stacking, on the other hand, requires high equipment precision and has low manufacturing efficiency, increasing production difficulty. Regarding the two manufacturing processes mentioned above, the former is mainly used in energy storage and passenger vehicle batteries. The main challenge is that the edges of the positive electrode need to be treated to prevent short circuits. Another challenge is that due to the small size of consumer batteries and the small spacing between the tabs, the rebound of the tabs can cause misalignment of the tabs, affecting welding. Stacked cells have many advantages: no winding bends, uniform interface, and tabs on each layer, making it the optimal construction method for high-rate batteries. However, it also has drawbacks such as low stacking efficiency and high precision requirements. Therefore, the centrally located tab technology is more suitable for high-rate consumer cells.

[0004] When the electrode film area of ​​a battery cell is long and has many winding layers, the single-tab structure intensifies the polarization of the cell itself, leading to drawbacks such as low capacity utilization, high internal resistance, and high battery surface temperature during charging and discharging. These phenomena mainly occur because with a long electrode, lithium ions near the tab have a shorter transport distance to the outside environment, while those farther from the tab have a longer transport distance, thus exacerbating the polarization of the entire electrode. This also makes the battery prone to interface inhomogeneity; after hundreds or thousands of charge-discharge cycles, the activity of the active materials becomes inconsistent, affecting the battery's cycle life.

[0005] The prior art includes a technology entitled "A Lithium-ion Battery Winding Structure" with publication number "108206302A". This technology includes a first electrode and a second electrode wound together, with opposite polarities. A separator is provided between the first electrode and the second electrode. From the innermost circle to the outermost circle, the first electrode sequentially includes a first blank current collector, a first single-sided current collector, and a first double-sided current collector. The second electrode sequentially includes a second blank current collector, a second double-sided current collector, and a second single-sided current collector. The first blank current collector is half a circle, and the first single-sided current collector is one circle. The side of the first single-sided current collector facing the outer circle of the lithium-ion battery winding structure is coated with a first active material. Both sides of the first double-sided current collector are coated with the first active material. The second blank current collector is one circle, and both sides of the second double-sided current collector are coated with a second active material. The side of the second single-sided current collector facing the inner circle of the lithium-ion battery winding structure is coated with a second active material.

[0006] However, this technology does not address the technical issues and solutions of this application. Summary of the Invention

[0007] The technical problem to be solved by the present invention is to provide a lithium-ion battery cell pack structure that can significantly improve the charge and discharge rate of wound cells and improve the overall performance and lifespan of the battery.

[0008] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: This invention relates to a lithium-ion battery core pack structure, comprising a negative electrode substrate and a positive electrode substrate. Multiple negative electrode paste layers are printed at intervals on the upper and lower surfaces of the negative electrode substrate, and multiple positive electrode paste layers are printed at intervals on the upper and lower surfaces of the positive electrode substrate. A negative electrode main tab is disposed at one end of the negative electrode substrate on the upper surface of the negative electrode substrate, and negative electrode secondary tabs are disposed at the gaps between the negative electrode paste layers on the upper surface of the negative electrode substrate. A positive electrode is disposed at one end of the positive electrode substrate on the upper surface of the positive electrode substrate. A positive electrode secondary electrode is provided in the gap between the positive electrode slurry layers on the upper surface of the positive electrode substrate, and a negative electrode secondary electrode is formed by a nickel metal strip and electrode adhesive; a positive electrode secondary electrode is formed by an aluminum metal strip and electrode adhesive; a negative electrode electrode is formed by a negative electrode substrate, a negative electrode slurry layer, a negative electrode main electrode, and a negative electrode secondary electrode; a positive electrode electrode is formed by a positive electrode substrate, a positive electrode slurry layer, a positive electrode main electrode, and a positive electrode secondary electrode; a separator is provided between the negative electrode and the positive electrode, and the negative electrode, positive electrode, and separator are wound together to form a wound battery cell.

[0009] The negative electrode main tab and multiple negative electrode secondary tabs are welded together; the positive electrode main tab and multiple positive electrode secondary tabs are welded together.

[0010] The negative electrode substrate is copper foil; the positive electrode substrate is aluminum foil.

[0011] The negative electrode tab is a nickel metal strip; the negative electrode tab is welded to the gap on the surface of the negative electrode substrate.

[0012] The positive and negative electrode tabs are aluminum metal strips; the positive and negative electrode tabs are welded to the gaps on the surface of the positive electrode substrate.

[0013] The present invention also relates to a method for forming a lithium-ion battery cell pack structure that can significantly improve the charge-discharge rate of wound cells and improve the overall performance and lifespan of the battery.

[0014] The forming steps of the method for forming the lithium-ion battery cell pack structure are as follows: S1. Print a negative electrode paste layer on the slit negative electrode substrate of fixed width and bake it at high temperature. After baking, pass it through a pressure roller to improve the compaction density. Print a positive electrode paste layer on the slit positive electrode substrate of fixed width and bake it at high temperature. After baking, pass it through a pressure roller to improve the compaction density. S2. Combine the nickel metal strip with the tab adhesive to form the negative electrode main tab, and weld the negative electrode main tab to the end position of the negative electrode substrate near one end on the upper surface of the negative electrode sheet substrate; set the negative electrode secondary tabs in the gaps between the negative electrode slurry layers on the upper surface of the negative electrode sheet substrate to obtain the negative electrode sheet. S3. Combine aluminum metal strip with tab adhesive to form positive electrode main tab, and weld the positive electrode main tab to the positive electrode substrate near one end of the positive electrode substrate on the upper surface of the positive electrode sheet substrate; set positive electrode secondary tabs in the gaps between the positive electrode slurry layers on the upper surface of the positive electrode sheet substrate to obtain the positive electrode sheet. S4. Arrange the separator between the negative electrode and the positive electrode, then wind the negative electrode, separator, and positive electrode together; then weld the negative main electrode tab and the negative secondary electrode tab together; weld the positive main electrode tab and the positive secondary electrode tab together; to form a wound battery cell.

[0015] Before placing the separator between the negative and positive electrodes, apply adhesive to the surface of the negative electrode to cover the welding burrs on the negative electrode; apply adhesive to the surface of the positive electrode to cover the welding burrs on the positive electrode.

[0016] After the electrodes are welded, the wound battery cell is sealed with adhesive.

[0017] The negative electrode substrate is made of copper foil; the positive electrode substrate is made of aluminum foil.

[0018] The working principle and beneficial effects of the technical solution adopted in this invention are as follows: Compared to existing battery cell structure technologies, the lithium-ion battery cell pack structure of this invention redesigns the film distribution of the electrode sheets, selects specific positions for the tabs, and increases the number of tabs, effectively reducing the internal resistance and polarization of the cell and increasing the charge / discharge rate of the cell. Simultaneously, this invention welds tabs at three positions—the head, tail, and middle—of the electrode sheet. The main tabs and negative tabs employ a design with varying widths to increase the overlap area of ​​the tabs and facilitate welding. The slurry layer uses a gap coating, with gaps reserved on the upper surface of the corresponding electrode substrate for welding the secondary tabs, and corresponding gaps also need to be reserved on the lower surface of the corresponding electrode substrate. The secondary tabs of the corresponding electrode sheets are all narrow tabs and do not have tab adhesive, facilitating welding to the main tabs. In this invention, both the positive and negative electrode sheets adopt a three-tab design structure (head, tail, and middle), effectively leveraging the rate advantage of multiple tabs and improving the charge / discharge rate of the cell. Compared to single-pole winding, the battery cells prepared by this invention have significant advantages in internal resistance and the proportion of constant voltage charging time. During high-rate charge-discharge cycles, the surface temperature rise of the battery cell is small, effectively solving existing problems. Attached Figure Description

[0019] The following is a brief explanation of the contents depicted in the accompanying drawings and the markings therein: Figure 1 This is a schematic diagram of the structure of the lithium-ion battery core pack structure after the negative electrode substrate is printed with the negative electrode paste layer. Figure 2 This is a schematic diagram of the structure of the lithium-ion battery core pack structure after the positive electrode substrate is printed with the positive electrode paste layer. Figure 3 This is a schematic diagram of the negative electrode sheet of the lithium-ion battery cell pack structure described in this invention; Figure 4 This is a schematic diagram of the positive electrode sheet of the lithium-ion battery cell pack structure described in this invention; Figure 5 This is a schematic diagram of the wound structure of the lithium-ion battery cell pack described in this invention; The labels in the attached diagram are as follows: 1. Negative electrode sheet; 2. Positive electrode sheet; 3. Separator membrane; 101. End of negative electrode substrate; 102. Gap portion of negative electrode substrate; 106. Negative electrode slurry layer; 107. Main negative electrode tab; 108. Secondary negative electrode tab; 109. Negative electrode sheet substrate; 201. End of positive electrode substrate; 202. Gap portion of positive electrode substrate; 206. Positive electrode slurry layer; 207. Main positive electrode tab; 208. Secondary positive electrode tab; 209. Positive electrode sheet substrate. Detailed Implementation

[0020] The following description, with reference to the accompanying drawings, provides a more detailed explanation of the specific embodiments of the present invention, including the shape and structure of each component, the relative positions and connections between the parts, the functions and working principles of each part: As attached Figure 1 -Appendix Figure 5As shown, this invention relates to a lithium-ion battery core pack structure, including a negative electrode substrate 109 and a positive electrode substrate 209. Multiple negative electrode paste layers 106 are printed at intervals on the upper and lower surfaces of the negative electrode substrate 109. Multiple positive electrode paste layers 206 are printed at intervals on the upper and lower surfaces of the positive electrode substrate 209. A negative electrode main tab 107 is provided at the negative electrode substrate end 101 near one end of the upper surface of the negative electrode substrate 109. Negative electrode secondary tabs 108 are provided at the gaps 102 between the negative electrode paste layers 106 on the upper surface of the negative electrode substrate 109. A positive electrode main tab 207 is provided at the positive electrode substrate end 201 near one end of the upper surface of the positive electrode substrate 209. The positive electrode paste layers 106 on the upper surface of the positive electrode substrate 209 are also provided. Positive and negative electrode tabs 208 are respectively provided in the gaps 202 between the positive electrode substrates of layers 206; a nickel metal strip and electrode adhesive form a negative electrode tab 108; an aluminum metal strip and electrode adhesive form a positive and negative electrode tab 208; a negative electrode substrate 109, a negative electrode slurry layer 106, a negative electrode main tab 107, and a negative electrode tab 108 form a negative electrode sheet 1; a positive electrode substrate 209, a positive electrode slurry layer 206, a positive electrode main tab 207, and a positive and negative electrode tab 208 form a positive electrode sheet 2; a separator 3 is provided between the negative electrode sheet 1 and the positive electrode sheet 2; the negative electrode sheet 1, the positive electrode sheet 2, and the separator 3 are wound to form a wound battery cell; the negative electrode main tab 107 and the negative electrode tab 108 have different widths; the positive electrode main tab 207 and the positive and negative electrode tab 208 have different widths. The above structure addresses the shortcomings of the prior art and proposes an improved technical solution. Compared to existing battery cell pack structures, this invention redesigns the film distribution of the electrode sheets, increases the number of tabs, further reduces the internal resistance and polarization of the cell, and increases the charge / discharge rate of the cell. Simultaneously, this invention welds tabs at three positions: the beginning, end, and middle of the electrode sheet. The main and negative tabs employ a design with varying widths to increase the overlap area of ​​the tabs and facilitate welding. The slurry layer uses a gap coating, with gaps reserved on the upper surface of the corresponding electrode substrate for welding the secondary tabs, and corresponding gaps also reserved on the back of the lower surface of the corresponding electrode substrate. The secondary tabs of the corresponding electrode sheets are narrow and do not have tab adhesive, facilitating welding to the main tabs. In this invention, both the positive and negative electrode sheets adopt a three-tab design structure (beginning, end, and middle), effectively leveraging the rate advantage of multiple tabs and improving the charge / discharge rate of the cell. Compared to single-tab winding, the cells prepared by this invention have significant advantages in internal resistance and the proportion of constant voltage charging time.During the core-packaging structure preparation, a negative electrode paste layer 106 is printed on a pre-cut and fixed-width negative electrode substrate 109, and baked at high temperature. After drying, it is passed through a pressure roller to increase the compaction density. A positive electrode paste layer 206 is printed on a pre-cut and fixed-width positive electrode substrate 209, and baked at high temperature. After drying, it is passed through a pressure roller to increase the compaction density. A nickel metal strip is combined with tab adhesive to form a negative electrode main tab 107, and the negative electrode main tab is welded to the negative electrode substrate end 101 near one end of the upper surface of the negative electrode substrate 109. Negative electrode secondary tabs 108 are respectively provided in the negative electrode substrate gaps 102 between the negative electrode paste layers 106 on the upper surface of the negative electrode substrate 109, resulting in... A negative electrode 1 is formed by bonding an aluminum strip with tab adhesive to form a positive main electrode tab 207, which is then welded to the positive electrode substrate end 201 near one end of the positive electrode substrate on the upper surface of the positive electrode substrate 209. Positive secondary electrode tabs 208 are respectively provided in the gaps 202 between the positive electrode slurry layers 206 on the upper surface of the positive electrode substrate 209 to obtain a positive electrode 2. A separator 3 is placed between the negative electrode 1 and the positive electrode 2, and then the negative electrode 1, separator 3, and positive electrode 2 are wound together. The negative main electrode tab 107 and the negative secondary electrode tab 108 are then welded together. The positive main electrode tab 207 and the positive secondary electrode tab 208 are also welded together, forming a wound battery cell. The structure of this invention results in a small surface temperature rise of the battery cell during high-rate charge-discharge cycles, effectively solving existing problems. The lithium-ion battery cell pack structure of the present invention can significantly improve the charge and discharge rate of wound cells, thereby improving the overall performance and lifespan of the battery.

[0021] The negative electrode main tab 107 and multiple negative electrode auxiliary tabs 108 are welded together; the positive electrode main tab 207 and multiple positive electrode auxiliary tabs 208 are welded together. In the above structure, the tabs of each electrode are welded to the corresponding electrode substrate to ensure reliable connection. Each electrode has multiple tabs, and the placement of each tab is specifically defined.

[0022] The negative electrode substrate 109 is copper foil; the positive electrode substrate 209 is aluminum foil. The negative electrode secondary tab 108 is a nickel metal strip; the negative electrode secondary tab 108 is welded to the gap portion on the upper surface of the negative electrode substrate 109. In this structure, during the printing of the negative electrode paste layer, the negative electrode substrate gap portion 102 and the negative electrode substrate end 101 are reserved to facilitate the welding of the corresponding tabs. The tabs include a negative electrode main tab and multiple negative electrode secondary tabs (in this embodiment, there are a total of three negative electrode tabs: one negative electrode main tab and two negative electrode secondary tabs). Thus, with the multiple negative electrode tabs, after winding to form the cell structure, the three negative electrode tabs need to be welded. The positive electrode secondary tab 208 is an aluminum metal strip; the positive electrode secondary tab 208 is welded to the gap portion on the upper surface of the positive electrode substrate 209. In the above structure, during the printing of the positive electrode paste layer, the positive electrode substrate has pre-reserved gap portions 202 and end portions 201 to facilitate the welding of the corresponding electrode tabs. The electrode tabs include a main positive electrode tab and multiple secondary positive electrode tabs (in the embodiment of this invention, there are a total of three positive electrode tabs: one main positive electrode tab and two secondary positive electrode tabs). Thus, with multiple positive electrode tabs, after the cell structure is formed by winding, the three positive electrode tabs need to be welded.

[0023] According to a specific embodiment of the present invention, the structure of the product is described in detail below: Nickel metal strips are combined with tab adhesive to form the negative electrode main tab, with a width of 8mm for the negative electrode main tab and 4mm for the negative electrode secondary tab. Aluminum metal strips are combined with tab adhesive to form the positive electrode main tab, with a width of 8mm for the positive electrode main tab and 4mm for the positive electrode secondary tab. 6μm copper foil is cut into rolls of a certain width to serve as the negative electrode substrate, and 12μm aluminum foil is cut into rolls of a certain width to serve as the positive electrode substrate, to be used in the coating process. The aluminum foil width is 93mm, the copper foil width is 95mm, and the separator width is 98mm. The positive and negative electrode slurries, with adjusted viscosity, are coated onto the aluminum and copper foils respectively. The positive electrode coating surface density is 0.170mg / mm², and the negative electrode is 0.087mg / mm². Both positive and negative electrodes require gap coating, leaving gaps for tab welding. The gap width is 25mm, and the length is the same as the substrate width. After the slurry coating is completed, the electrode sheets are baked at high temperature in an oven. Once the electrode sheets are dry, a cold pressing process is performed. The cold pressing thickness of the positive electrode is 97±5μm, and the cold pressing thickness of the negative electrode is 114±5μm. The cold-pressed negative electrode sheet is placed in a high-temperature air box to fully release the rebound thickness and prevent misalignment of the electrode tabs due to rebound. The positive electrode sheet, the separator, and the negative electrode sheet are wound together to obtain a wound cell. The two secondary electrodes of the positive electrode are then welded to the primary electrodes, and the negative electrode is treated in the same way to obtain the finished bare cell. The bare cell is then placed in a slit aluminum-plastic film, and the sealing head temperature is 185±5℃. Subsequent processes for the cell can be carried out according to the normal production process, including baking, electrolyte injection, formation, venting, and capacity testing, to complete the preparation of the core-pack structure. The process is reliable.

[0024] The present invention also relates to a method for forming a lithium-ion battery cell pack structure that can significantly improve the charge-discharge rate of wound cells and improve the overall performance and lifespan of the battery.

[0025] The forming steps of the method for forming the lithium-ion battery cell pack structure are as follows: S1. A negative electrode paste layer 106 is printed on the slit and fixed-width negative electrode substrate 109, and baked at high temperature. After baking and drying, it is passed through a pressure roller to improve the compaction density. A positive electrode paste layer 206 is printed on the slit and fixed-width positive electrode substrate 209, and baked at high temperature. After baking and drying, it is passed through a pressure roller to improve the compaction density. S2. A nickel metal strip is combined with tab adhesive to form a negative electrode main tab 107. The negative electrode main tab is welded to the negative electrode substrate end 101 near one end of the upper surface of the negative electrode substrate 109. Negative electrode secondary tabs 108 are respectively provided in the negative electrode substrate gaps 102 between the negative electrode paste layers 106 on the upper surface of the negative electrode substrate 109 to obtain the negative electrode 109. S3. Combine aluminum metal strip with tab adhesive to form positive main tab 207, and weld positive main tab 207 to the positive electrode substrate end 201 near one end of the positive electrode substrate on the upper surface of positive electrode substrate 209; set positive secondary tabs 208 in the gaps 202 between the positive electrode slurry layers 206 on the upper surface of positive electrode substrate 209 to obtain positive electrode 2; S4. Arrange separator 3 between negative electrode 1 and positive electrode 2, and then wind negative electrode 1, separator 3 and positive electrode 2; then weld negative main tab 107 and negative secondary tab 108; weld positive main tab 207 and positive secondary tab 208; to form a wound battery cell.

[0026] Before placing the separator 3 between the negative electrode 1 and the positive electrode 2, adhesive is applied to the surface of the negative electrode 1 to cover the welding burrs on the negative electrode 1; adhesive is also applied to the surface of the positive electrode 2 to cover the welding burrs on the positive electrode 2. After the tabs are welded, the wound cell is sealed after applying adhesive.

[0027] The negative electrode substrate 109 is made of copper foil; the positive electrode substrate 209 is made of aluminum foil. The negative electrode main tab is a nickel metal strip; the positive electrode main tab is an aluminum metal strip.

[0028] Compared to existing battery cell structure technologies, the lithium-ion battery cell pack structure of this invention redesigns the film distribution of the electrode sheets, selects specific positions for the tabs, and increases the number of tabs, effectively reducing the internal resistance and polarization of the cell and increasing the charge / discharge rate of the cell. Simultaneously, this invention welds tabs at three positions—the head, tail, and middle—of the electrode sheet. The main tabs and negative tabs employ a design with varying widths to increase the overlap area of ​​the tabs and facilitate welding. The slurry layer uses a gap coating, with gaps reserved on the upper surface of the corresponding electrode substrate for welding the secondary tabs, and corresponding gaps also need to be reserved on the lower surface of the corresponding electrode substrate. The secondary tabs of the corresponding electrode sheets are all narrow tabs and do not have tab adhesive, facilitating welding to the main tabs. In this invention, both the positive and negative electrode sheets adopt a three-tab design structure (head, tail, and middle), effectively leveraging the rate advantage of multiple tabs and improving the charge / discharge rate of the cell. Compared to single-pole winding, the battery cells prepared by this invention have significant advantages in internal resistance and the proportion of constant voltage charging time. During high-rate charge-discharge cycles, the surface temperature rise of the battery cell is small, effectively solving existing problems.

[0029] The present invention has been described above by way of example with reference to the accompanying drawings. Obviously, the specific implementation of the present invention is not limited to the above-described manner. Any improvements made by adopting the inventive concept and technical solution of the present invention, or the direct application of the inventive concept and technical solution of the present invention to other occasions without modification, are all within the protection scope of the present invention.

Claims

1. A lithium-ion battery cell pack structure, characterized in that: The substrate includes a negative electrode substrate (109) and a positive electrode substrate (209). Multiple negative electrode paste layers (106) are printed at intervals on the upper and lower surfaces of the negative electrode substrate (109). Multiple positive electrode paste layers (206) are printed at intervals on the upper and lower surfaces of the positive electrode substrate (209). A negative electrode main tab (107) is provided at the negative electrode substrate end (101) near one end of the upper surface of the negative electrode substrate (109). Negative electrode secondary tabs (108) are provided at the negative electrode substrate gaps (102) between the negative electrode paste layers (106) on the upper surface of the negative electrode substrate (109). A positive electrode main tab (207) is provided at the positive electrode substrate end (201) near one end of the upper surface of the positive electrode substrate (209). Positive electrode tabs (208) are respectively provided in the gaps (202) between the positive electrode slurry layers (206) on the upper surface of the positive electrode substrate; a nickel metal strip and tab adhesive form a negative electrode tab (108); an aluminum metal strip and tab adhesive form a positive electrode tab (208); a negative electrode substrate (109), a negative electrode slurry layer (106), a negative electrode main tab (107), and a negative electrode tab (108) form a negative electrode sheet (1); a positive electrode substrate (209), a positive electrode slurry layer (206), a positive electrode main tab (207), and a positive electrode tab (208) form a positive electrode sheet (2); a separator (3) is provided between the negative electrode sheet (1) and the positive electrode sheet (2), and the negative electrode sheet (1), the positive electrode sheet (2), and the separator (3) are wound together to form a wound battery cell; The negative electrode main tab (107) and negative electrode secondary tab (108) have different widths; the positive electrode main tab (207) and positive electrode secondary tab (208) have different widths. The negative electrode main electrode tab (107) and multiple negative electrode secondary electrode tabs (108) are welded together; the positive electrode main electrode tab (207) and multiple positive electrode secondary electrode tabs (208) are welded together. After the slurry coating is completed, the electrode sheet is baked at high temperature in an oven. After the electrode sheet is dry, a cold pressing process can be carried out. The positive electrode is cold pressed and the negative electrode is cold pressed. The cold-pressed electrode sheet is placed in a high-temperature air box to release the rebound thickness and prevent the electrode sheet from causing misalignment of the electrode tab welding due to rebound.

2. The lithium-ion battery cell pack structure according to claim 1, characterized in that: The negative electrode substrate (109) is copper foil; the positive electrode substrate (209) is aluminum foil.

3. The lithium-ion battery cell pack structure according to claim 1 or 2, characterized in that: The negative electrode tab (108) is a nickel metal strip; the negative electrode tab (108) is welded to the gap on the upper surface of the negative electrode substrate (109).

4. The lithium-ion battery cell pack structure according to claim 1 or 2, characterized in that: The positive and negative electrode tabs (208) are aluminum metal strips; the positive and negative electrode tabs (208) are welded to the gaps on the upper surface of the positive electrode substrate (209).

5. A method for forming a lithium-ion battery cell pack structure according to any one of claims 1 to 4, characterized in that: The forming steps of the forming method for the lithium-ion battery cell pack structure are as follows: S1. A negative electrode paste layer (106) is printed on the negative electrode substrate (109) that has been cut to a fixed width, and baked at high temperature. After baking, it is passed through a pressure roller to improve the compaction density. A positive electrode paste layer (206) is printed on the positive electrode substrate (209) that has been cut to a fixed width, and baked at high temperature. After baking, it is passed through a pressure roller to improve the compaction density. S2. The nickel metal strip is combined with the tab adhesive to form the negative electrode main tab (107), and the negative electrode main tab is welded to the negative electrode substrate end (101) near one end of the upper surface of the negative electrode substrate (109); negative electrode secondary tabs (108) are respectively provided in the negative electrode substrate gap (102) between the negative electrode slurry layers (106) on the upper surface of the negative electrode substrate (109) to obtain the negative electrode (1). S3. The aluminum metal strip is combined with the tab adhesive to form the positive electrode main tab (207). The positive electrode main tab (207) is welded to the positive electrode substrate end (201) near one end of the upper surface of the positive electrode substrate (209). Positive electrode secondary tabs (208) are respectively set in the positive electrode substrate gap (202) between the positive electrode slurry layers (206) on the upper surface of the positive electrode substrate (209) to obtain the positive electrode (2). S4. Arrange the separator (3) between the negative electrode plate (1) and the positive electrode plate (2), and then wind the negative electrode plate (1), separator (3), and positive electrode plate (2); then weld the negative main electrode tab (107) and the negative secondary electrode tab (108); weld the positive main electrode tab (207) and the positive secondary electrode tab (208); to form a wound battery cell.

6. The lithium-ion battery cell pack structure according to claim 5, characterized in that: Before placing the separator (3) between the negative electrode (1) and the positive electrode (2), apply adhesive to the surface of the negative electrode (1) to cover the welding burrs on the negative electrode (1); apply adhesive to the surface of the positive electrode (2) to cover the welding burrs on the positive electrode (2).

7. The lithium-ion battery cell pack structure according to claim 6, characterized in that: After the electrodes are welded, the wound battery cell is sealed with adhesive.

8. The lithium-ion battery cell pack structure according to claim 7, characterized in that: The negative electrode substrate (109) is made of copper foil; the positive electrode substrate (209) is made of aluminum foil.

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