Method for preparing battery tab with middle placement and battery with middle placement tab

Abstract

The present disclosure relates to the technical field of batteries, and provides a battery tab centering preparation method and a tab centering battery. The battery tab centering preparation method comprises a coating step, a cutting step, a stacking step and a winding step. The tab centering battery can be prepared by the battery tab centering preparation method. The battery tab centering preparation method is simple in steps, can be efficiently applied to an industrial production line, and finally prepares the tab centering battery. The first electrode is centered, thereby reducing the length of the electronic transmission path, reducing the internal resistance of the battery cell, and making the charging and discharging process of the battery cell more efficient. The second electrodes at both ends of the battery cell are equivalent to parallel shunt settings, which can correspondingly reduce the heat generation in the charging and discharging process, improve the rate capability, and improve the cycle capability of the battery cell.

Description

Technical Field

[0001] This disclosure relates to the field of battery technology, and in particular to a method for preparing a battery with a centrally located tab and a battery with a centrally located tab. Background Technology

[0002] In existing cylindrical batteries, the positive and negative tabs are typically located at the top and bottom of the battery, respectively. However, when the height of this conventional cylindrical battery increases, the electron transport path along the battery core will lengthen accordingly, thereby increasing the battery's internal resistance and affecting the charging and discharging efficiency of the cylindrical battery.

[0003] Currently, there are also novel electrode tab placement schemes used in cylindrical batteries. That is, the positive or negative electrode tabs of the cylindrical battery are placed in the middle of the battery core, thereby shortening the electron transmission path and reducing the internal resistance of the battery. However, the manufacturing process of cylindrical batteries with electrode tab placement in this existing technology is more complicated and the production cost is higher. Summary of the Invention

[0004] This disclosure provides a method for manufacturing a battery with centrally located tabs and a battery with centrally located tabs, in order to solve the problems of complex processes and high production costs of cylindrical batteries with centrally located tabs in related technologies.

[0005] The battery tab placement method provided in this embodiment includes the following steps:

[0006] In the coating step, electrode paste is coated onto the current collector to form a first electrode and a second electrode, and an uncoated first blank area is formed in the middle of the first electrode along the width direction, and an uncoated second blank area is formed in the middle of the second electrode along the width direction. The cutting step involves cutting the second electrode along the centerline of the width direction to form two identical second sub-electrodes, and cutting the second blank area to form two identical electrode tabs; In the stacking step, two second sub-electrodes are sandwiched and stacked on one side of the first electrode by a diaphragm, and the two electrode tabs protrude from both ends of the first electrode along its length. In the winding step, the first electrode, the diaphragm, and the two second sub-electrodes are wound along the width direction to form a battery cell, so that the first blank area is wound to form a first electrode located in the middle of the battery cell, and the tab portion is wound to form a second electrode located at both ends of the battery cell.

[0007] In one possible implementation, the coating step includes: The electrode slurry includes a positive electrode slurry and a negative electrode slurry. The positive electrode slurry is coated onto the current collector to form the first electrode, and the negative electrode slurry is coated onto the current collector to form the second electrode.

[0008] In one possible implementation, the coating step includes: The electrode slurry includes a positive electrode slurry and a negative electrode slurry. The negative electrode slurry is coated onto the current collector to form the first electrode, and the positive electrode slurry is coated onto the current collector to form the second electrode.

[0009] In one possible implementation, the cutting step includes: Cut along the extension direction of the second blank area to form two identical tab portions, and cut a plurality of parallel tab units of equal height in the tab portions.

[0010] In one possible implementation, the width of the first blank area is set to be between 1mm and 100mm; Set the width of the second blank area to 1mm~100mm.

[0011] In one embodiment, a metal foil with a thickness of 0.02 mm to 0.30 mm is used as the current collector.

[0012] In addition, this disclosure also provides a battery with a centrally located tab, which can be prepared by the above-described battery preparation method with a centrally located tab, and includes a cell, a first electrode, and a second electrode. The battery cell is formed by winding electrode sheet material, and the electrode sheet includes a first electrode sheet, a separator and a second sub-electrode sheet stacked in sequence. The first electrode has an uncoated first blank area along its width direction; Two second sub-electrodes are spaced apart along the length direction of the first electrode, and each of the two second sub-electrodes has an electrode tab that protrudes from the end of the first electrode along the length direction; The first blank area can be wound to form a first electrode located in the middle of the battery cell; The tabs can be wound to form second electrodes located at both ends of the battery cell.

[0013] In one embodiment, a positive electrode paste is coated on the first electrode sheet, and the first electrode formed by winding the first blank area is the positive electrode; The second electrode is coated with a negative electrode paste, and the second electrode formed by the winding of the electrode tab is the negative electrode.

[0014] In one embodiment, a negative electrode paste is coated on the first electrode sheet, and the first electrode formed by winding the first blank area is the negative electrode; The second electrode is coated with a positive electrode paste, and the second electrode formed by the winding of the tab is the positive electrode.

[0015] In one possible embodiment, the width of the first electrode is set to be in the range of 1mm to 100mm; The width of the second electrode is set to be between 1mm and 50mm.

[0016] The technical solution provided in this disclosure has the following advantages compared with related technologies: The battery tab placement method provided in this disclosure is simple in steps and can be efficiently applied to industrial production lines. The resulting battery cell can centrally place the first electrode, thereby reducing the electron transport path length, lowering the internal resistance of the battery cell, and making the charging and discharging process of the battery cell more efficient. Furthermore, the second electrodes at both ends of the battery cell are equivalent to a parallel current splitting arrangement, which can correspondingly reduce the heat generated during the charging and discharging process, improve the rate capability, and improve the cycle life of the battery cell.

[0017] In addition, the battery with centrally located tabs provided in this embodiment can be prepared by the above-mentioned method for preparing batteries with centrally located tabs, and has the advantages of simple preparation process, low production cost, low battery internal resistance, and high charge and discharge efficiency.

[0018] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of this disclosure, nor is it intended to limit the scope of this disclosure. Other features of this disclosure will become readily apparent from the following description. Attached Figure Description

[0019] The above and other objects, features, and advantages of this disclosure will become readily apparent from the following detailed description of exemplary embodiments, taken in conjunction with the accompanying drawings. Several embodiments of this disclosure are illustrated in the drawings by way of example and not limitation, in which: In the accompanying drawings, the same or corresponding reference numerals indicate the same or corresponding parts.

[0020] Figure 1 A schematic diagram of the process of the battery tab placement preparation method provided in the embodiments of this disclosure is shown; Figure 2 A flowchart of the battery tab placement preparation method provided in this disclosure embodiment is shown; Figure 3 A schematic diagram of a tab-centered battery provided in an embodiment of this disclosure is shown.

[0021] The following are the labels in the diagram: 1. First electrode; 11. First blank area; 2. Second electrode; 20. Second sub-electrode; 21. Second blank area; 211. Electrode tab; 3. Diaphragm; 4. Cell; 5. First electrode; 6. Second electrode. Detailed Implementation

[0022] To make the objectives, features, and advantages of this disclosure more apparent and understandable, the technical solutions in the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this disclosure, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this disclosure without creative effort are within the scope of protection of this disclosure.

[0023] The embodiments of this disclosure will now be described in detail with reference to the accompanying drawings.

[0024] Combination Figure 1 and Figure 2 As shown in the figure, this disclosure provides a method for preparing a battery tab, which includes the following steps: Coating step S1—The electrode paste is coated onto the current collector to form the first electrode 1 and the second electrode 2, and an uncoated first blank area 11 is formed in the middle of the first electrode 1 along the width direction, and an uncoated second blank area 21 is formed in the middle of the second electrode 2 along the width direction. Cutting step S2—Cut the second pole piece 2 along the centerline of the width direction to form two identical second sub-pole pieces 20, and cut the second blank area 21 to form two identical pole ears 211; Stacking step S3—Two second sub-electrodes 20 are sandwiched and stacked on one side of the first electrode 1 through the diaphragm 3, and the two electrode tabs 211 protrude from both ends of the first electrode 1 along its length. Winding step S4—The first electrode 1, the diaphragm 3 and the two second sub-electrodes 20 are wound along the width direction to form a battery cell 4, the first blank area 11 is wound to form a first electrode 5 located in the middle of the battery cell 4, and the tabs 211 are wound to form second electrodes 6 located at both ends of the battery cell 4.

[0025] The battery tab fabrication method provided in this embodiment can simultaneously fabricate two first electrode sheets 1 and second electrode sheets 2 with different electrode polarities in the coating step S1, and form an uncoated first blank area 11 and a second blank area 21 along the width direction in the middle of the first electrode sheet 1 and the second electrode sheet 2, respectively; in the cutting step S2, only the second electrode sheet 2 is cut, and the second electrode sheet 2 is "divided into two" to form two identical second sub-electrodes 20, and at the same time, the second blank area 21 is "divided into two" to form two identical tab portions. 211; In the stacking step S3, the two second sub-electrodes 20 are simultaneously sandwiched by the two diaphragms 3 and then stacked on one side of the first electrode 1, and the two tabs 211 protrude from both ends of the first electrode in the length direction; In the winding step S4, the first electrode 1, the diaphragm 3 and the two second sub-electrodes 20 are wound along the width direction to form the battery cell 4, and at this time the first blank area 11 is wound to form the centrally located first electrode 5 in the middle of the battery cell 4, and the tabs 211 are wound to form the second electrodes 6 at both ends of the battery cell 4.

[0026] Furthermore, when the first electrode 5 is connected to the positive busbar as a positive electrode, the second electrode 6 can be connected to the negative busbar as a negative electrode; when the first electrode 5 is connected to the negative busbar as a negative electrode, the second electrode 6 can be connected to the positive busbar as a positive electrode.

[0027] In summary, the battery tab placement method provided in this embodiment is simple in steps, can be efficiently applied to industrial production lines, and the final battery cell 4 can achieve the placement of the first electrode 5 in the center, thereby reducing the electron transport path length, reducing the internal resistance of the battery cell 4, and making the charging and discharging process of the battery cell 4 more efficient; and the second electrodes 6 at both ends of the battery cell 4 are equivalent to a parallel current splitting arrangement, which can correspondingly reduce the heat generation during the charging and discharging process, improve the rate capability, and improve the cycle capability of the battery cell 4.

[0028] Therefore, the cylindrical battery prepared by the battery tab placement method provided in this embodiment can have a higher height limit, increase the capacity of a single cell, maintain a high rate capability, and have a lower manufacturing cost. Since the first electrode 5 in the cell 4 is placed in the center, the length of the electron transport path can be reduced and the internal resistance of the cell 4 can be reduced. The second electrode 6 in the cell 4 is arranged in parallel, which can also reduce the heat generation during the charging and discharging process, improve the overcurrent capability, and improve the cycle performance of the cell 4.

[0029] In one embodiment, the coating step S1 includes: The electrode paste includes a positive electrode paste and a negative electrode paste. The positive electrode paste is coated onto the current collector to form a first electrode 1, and the negative electrode paste is coated onto the current collector to form a second electrode 2.

[0030] Specifically, at this time, the positive electrode paste is coated onto the current collector to form the first electrode 1, and the negative electrode paste is coated onto the current collector to form the second electrode 2. Thus, the first electrode 1 corresponds to the positive electrode, and the first electrode 5 formed by the first blank area 11 in the first electrode 1 after being wound up corresponds to the positive electrode; the second electrode 2 corresponds to the negative electrode, and the second electrode 6 formed by the tab 211 in the second electrode 2 after being wound up corresponds to the negative electrode. That is, the battery cell 4 produced at this time has a structure of "positive electrode in the middle and negative electrodes facing both ends in parallel".

[0031] In one embodiment, the coating step S1 includes: The electrode paste includes a positive electrode paste and a negative electrode paste. The negative electrode paste is coated onto the current collector to form a first electrode 1, and the positive electrode paste is coated onto the current collector to form a second electrode 2.

[0032] Specifically, at this time, negative electrode paste is coated onto the current collector to form the first electrode 1, and positive electrode paste is coated onto the current collector to form the second electrode 2. Thus, the first electrode 1 corresponds to the negative electrode, and the first electrode 5 formed by the first blank area 11 in the first electrode 1 after being wound up corresponds to the negative electrode; the second electrode 2 corresponds to the positive electrode, and the second electrode 6 formed by the electrode tab 211 in the second electrode 2 after being wound up corresponds to the positive electrode. That is, the battery cell 4 produced at this time has a structure of "negative electrode in the middle and positive electrode facing both ends in parallel".

[0033] In one embodiment, the cutting step S2 includes: Cut along the extension direction of the second blank area 21 to form two identical tab portions 211, and cut several parallel tab units of equal height in the tab portions 211.

[0034] Specifically, in combination Figure 1 To explain in more detail, the second blank area 21 can be divided into two along its centerline by clamping and cutting, while simultaneously cutting the outer side of the tab portion 211. For example, the tab unit in the tab portion 211 can be set as... Figure 1 The isosceles trapezoids in the middle are arranged in parallel along the same straight line in the tab 211.

[0035] In one embodiment, the width of the first blank area 11 is set to a range of 1mm to 100mm; and the width of the second blank area 21 is set to a range of 1mm to 100mm.

[0036] Specifically, the widths of the first blank area 11 and the second blank area 21 can be flexibly adjusted between 1mm and 100mm according to actual current requirements. When the width range of the first blank area 11 and the second blank area 21 is selected between 2mm and 20mm, it can basically meet the general current requirements and ensure that the first electrode 5 and the second electrode 6 formed after the final winding have sufficient welding size to be firmly welded to the busbar.

[0037] In one embodiment, a metal foil with a thickness of 0.02 mm to 0.30 mm is used as the current collector.

[0038] Specifically, aluminum or copper foil with a thickness of 0.02mm-0.30mm can be used as the current collector. This ensures that the current collector has sufficient structural strength for the electrode paste to adhere to, and also ensures that the current collector has excellent conductivity and current collection performance.

[0039] In addition, this disclosure also provides a battery with a centrally located tab, which can be prepared by the above-described battery tab-centered preparation method. It includes a cell 4, a first electrode 5, and a second electrode 6. The cell 4 is formed by winding electrode sheet material, and the electrode sheet includes a first electrode sheet 1, a separator 3, and a second sub-electrode sheet 20 stacked in sequence. The first electrode sheet 1 has an uncoated first blank area 11 along its width direction. Two second sub-electrodes 20 are spaced apart along the length direction of the first electrode sheet 1, and each of the two second sub-electrodes 20 has a tab portion 211 protruding from the end of the first electrode sheet 1 along its length direction. The first blank area 11 can be wound to form a first electrode 5 located in the middle of the cell 4. The tab portion 211 can be wound to form a second electrode 6 located at both ends of the cell 4.

[0040] Specifically, in combination Figure 3 To further explain in detail, the battery with centrally located tabs provided in this embodiment can be prepared by the above-described method for preparing a battery with centrally located tabs. Moreover, the cell 4 of this battery with centrally located tabs can achieve the following: the first electrode 5 is centrally located in the middle of the cell, and the second electrode 6 is connected in parallel at both ends of the cell. Therefore, the cell 4 of this battery with centrally located tabs can reduce the length of the electron transport path, reduce the internal resistance of the cell 4, and make the charging and discharging process of the cell 4 more efficient. Furthermore, the second electrodes 6 at both ends of the cell 4 are equivalent to being connected in parallel to shunt the current, which can reduce the heat generated during the charging and discharging process, improve the rate capability, and improve the cycle capability of the cell 4.

[0041] In summary, the electrode-centered battery provided in this embodiment has the advantages of simple preparation process, low production cost, low internal resistance, and high charge and discharge efficiency.

[0042] In one embodiment, a positive electrode paste is coated on the first electrode 1, and the first electrode 5 formed by winding the first blank area 11 is the positive electrode; a negative electrode paste is coated on the second electrode 2, and the second electrode 6 formed by winding the tab 211 is the negative electrode.

[0043] Specifically, at this time, a positive electrode paste is coated on the first electrode 1, so the first electrode 1 corresponds to the positive electrode, and the first electrode 5 formed by the first blank area 11 in the first electrode 1 after being finally wound corresponds to the positive electrode; a negative electrode paste is coated on the second electrode 2, so the second electrode 2 corresponds to the negative electrode, and the second electrode 6 formed by the electrode tab 211 in the second electrode 2 after being finally wound corresponds to the negative electrode. That is, the battery cell 4 produced at this time has a structure of "positive electrode in the middle and negative electrodes facing both ends in parallel".

[0044] In one embodiment, a negative electrode paste is coated on the first electrode 1, and the first electrode 5 formed by winding the first blank area 11 is the negative electrode; a positive electrode paste is coated on the second electrode 2, and the second electrode 6 formed by winding the tab 211 is the positive electrode.

[0045] Specifically, at this time, a negative electrode paste is coated on the first electrode 1, so the first electrode 1 corresponds to the negative electrode, and the first electrode 5 formed by the final winding of the first blank area 11 in the first electrode 1 corresponds to the negative electrode; a positive electrode paste is coated on the second electrode 2, so the second electrode 2 corresponds to the positive electrode, and the second electrode 6 formed by the final winding of the tab 211 in the second electrode 2 corresponds to the positive electrode. That is, the battery cell 4 produced at this time has a structure of "negative electrode in the middle and positive electrodes facing both ends in parallel".

[0046] In one embodiment, the width of the first electrode 5 is set to a range of 1mm to 100mm; the width of the second electrode 6 is set to a range of 1mm to 50mm.

[0047] Specifically, the width of the first electrode 5 and the width of the second electrode 6 can be flexibly adjusted according to the actual overcurrent requirements. When the width of the first electrode 5 is selected to be in the range of 1mm to 100mm and the width of the second electrode 6 is set to be in the range of 1mm to 50mm, it can basically meet the general overcurrent requirements and ensure that the first electrode 5 and the second electrode 6 have sufficient welding size to be firmly welded to the busbar.

[0048] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this disclosure, "a plurality of" means two or more, unless otherwise explicitly specified.

[0049] The above are merely specific embodiments of this disclosure, but the scope of protection of this disclosure is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this disclosure should be included within the scope of protection of this disclosure. Therefore, the scope of protection of this disclosure should be determined by the scope of the claims.

Claims

1. A method for preparing a battery electrode tab with a centrally placed position, characterized in that, Includes the following steps: In the coating step, electrode paste is coated onto the current collector to form a first electrode (1) and a second electrode (2), and an uncoated first blank area (11) is formed in the middle of the first electrode (1) along the width direction, and an uncoated second blank area (21) is formed in the middle of the second electrode (2) along the width direction. In the cutting step, the second pole piece (2) is cut along the center line in the width direction to form two identical second sub-pole pieces (20), and the second blank area (21) is cut to form two identical pole ears (211). In the stacking step, two second sub-electrodes (20) are sandwiched and stacked on one side of the first electrode (1) through a diaphragm (3), and the two electrode tabs (211) protrude from both ends of the first electrode (1) along its length. In the winding step, the first electrode (1), the diaphragm (3) and the two second sub-electrodes (20) are wound along the width direction to form a battery cell (4), the first blank area (11) is wound to form a first electrode (5) located in the middle of the battery cell (4), and the tab portion (211) is wound to form a second electrode (6) located at both ends of the battery cell (4).

2. The method for preparing a battery tab according to claim 1, characterized in that, The coating step includes: The electrode slurry includes a positive electrode slurry and a negative electrode slurry. The positive electrode slurry is coated onto the current collector to form the first electrode (1), and the negative electrode slurry is coated onto the current collector to form the second electrode (2).

3. The method for preparing a battery tab according to claim 1, characterized in that, The coating step includes: The electrode slurry includes a positive electrode slurry and a negative electrode slurry. The negative electrode slurry is coated onto the current collector to form the first electrode (1), and the positive electrode slurry is coated onto the current collector to form the second electrode (2).

4. The method for preparing a battery tab according to claim 1, characterized in that, The cutting step includes: Cut along the extension direction of the second blank area (21) to form two identical tab portions (211), and cut a plurality of parallel tab units of equal height in the tab portions (211).

5. The method for preparing a battery tab according to claim 1, characterized in that, Set the width of the first blank area (11) to 1mm~100mm; Set the width of the second blank area (21) to 1mm~100mm.

6. The method for preparing a battery tab according to claim 1, characterized in that, A metal foil with a thickness of 0.02 mm to 0.30 mm is used as the current collector.

7. A battery with a centrally located tab, which can be prepared by the battery tab-centered preparation method according to any one of claims 1 to 6, characterized in that, Includes battery cell (4), first electrode (5), and second electrode (6); The battery cell (4) is formed by winding electrode sheet material, and the electrode sheet includes a first electrode sheet (1), a separator (3) and a second sub-electrode sheet (20) stacked in sequence. The first electrode (1) has an uncoated first blank area (11) along the width direction. Two second sub-electrodes (20) are spaced apart along the length direction of the first electrode (1), and each of the two second sub-electrodes (20) has an electrode tab (211) protruding from the end of the first electrode (1) along the length direction. The first blank area (11) can be wound to form a first electrode (5) located in the middle of the cell (4); The tab (211) can be wound to form a second electrode (6) located at both ends of the battery cell (4).

8. The battery with centrally located tabs according to claim 7, characterized in that, The first electrode (1) is coated with a positive electrode paste, and the first electrode (5) formed by winding the first blank area (11) is the positive electrode; The second electrode (2) is coated with a negative electrode paste, and the second electrode (6) formed by the winding of the tab (211) is the negative electrode.

9. The battery with centrally located tabs according to claim 7, characterized in that, The first electrode (1) is coated with a negative electrode paste, and the first electrode (5) formed by winding the first blank area (11) is a negative electrode; The second electrode (2) is coated with a positive electrode paste, and the second electrode (6) formed by the winding of the tab (211) is the positive electrode.

10. The battery with centrally located tabs according to claim 7, characterized in that, The width of the first electrode (5) is set to be 1mm to 100mm; The width of the second electrode (6) is set to be 1mm to 50mm.

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