Lithium battery pole piece, lithium battery cell, lithium battery and corresponding preparation method

Abstract

The application provides a lithium battery pole piece, a lithium battery cell, a lithium battery and a preparation method. The lithium battery pole piece comprises a metal bottom film, a frame-shaped material ring, battery paste and a pole lug. Because of the existence of the frame-shaped material ring, the lithium battery pole piece can avoid the risk of burrs on the pole piece and the puncture of the diaphragm caused by the characteristics of the metal bottom film and the knife die when cutting; the frame-shaped material ring wraps the battery paste therein, which can greatly solve the problem of powder falling of the battery paste or the metal bottom film; by arranging the frame-shaped material ring at the edge of the lithium battery pole piece, the insulation effect of the edge of the pole piece is ensured, which can effectively reduce the K value of the lithium battery; the edge size and shape of each lithium battery pole piece are the same, and the position, size and shape of the battery paste are also the same, which is conducive to efficiently achieving the alignment standard of the positive and negative pole pieces in the lamination process of preparing the lithium battery cell.

Description

Technical Field

[0001] This invention relates to the field of lithium battery manufacturing technology, and in particular to a lithium battery electrode, a lithium battery cell, a lithium battery, and a corresponding manufacturing method. Background Technology

[0002] Lithium-ion batteries are batteries that contain lithium (including metallic lithium, lithium alloys, lithium ions, and lithium polymers) in their electrochemical system. In recent years, the application range of lithium-ion batteries has become increasingly wide, with applications in energy storage systems such as hydropower, thermal power, wind power, and solar power plants, as well as in power tools, electric bicycles, electric motorcycles, electric cars, military equipment, aerospace, and many other fields. In this era of rapid development in lithium-ion battery technology, the industry is also placing increasingly higher demands on each process. One process in lithium-ion battery manufacturing involves stacking the positive and negative electrode sheets, which are cut to the correct size and shape and then combined with a separator to form a battery cell. However, due to material properties and die-cutting factors, cutting the lithium-ion battery electrode sheets can easily lead to burrs, powder shedding, and other defects. Furthermore, the stacking process in lithium-ion battery cell manufacturing requires a standard alignment of the positive and negative electrode sheets.

[0003] In view of the above, how to provide a lithium battery electrode sheet that avoids problems such as burrs and powder shedding during electrode sheet cutting due to material characteristics and die-cutting molds, while also meeting the standard of efficient alignment of positive and negative electrodes during the stacking process of lithium battery cell manufacturing. Summary of the Invention

[0004] In view of the shortcomings of the prior art described above, the purpose of this invention is to provide a lithium battery electrode sheet to solve the problems of burrs and powder shedding that occur when cutting the electrode sheet due to material characteristics and die-cutting molds in the prior art. At the same time, it can meet the standard of efficiently achieving the alignment of positive and negative electrode sheets in the stacking process of preparing lithium battery cells.

[0005] To achieve the above and other related objectives, the present invention provides a lithium battery electrode sheet, the lithium battery electrode sheet comprising: a metal base film; a frame-shaped material ring located above the metal base film for protecting the lithium battery electrode sheet; a battery slurry located inside the frame-shaped material ring, the thickness of the battery slurry being the same as the thickness of the frame-shaped material ring; and an electrode tab located on one side of the metal base film.

[0006] Optionally, the frame-shaped material ring is square in shape.

[0007] Optionally, the material of the frame-shaped material ring is one or a combination of two of the following: adhesive and ceramic slurry.

[0008] Optionally, the width of the frame-shaped material ring ranges from 2mm to 5mm, and the thickness ranges from 1μm to 20μm.

[0009] Optionally, the tab is located at the middle position on one side of the metal substrate.

[0010] This invention provides a method for preparing lithium battery electrode sheets, the method comprising the following steps:

[0011] S11: Provide a metal base film, form a matrix of frame-shaped material rings on the metal base film, the width of the frame-shaped material rings is in the range of 3mm to 10mm, and dry;

[0012] S12: Apply battery paste to the frame-shaped material ring, dry it again, and roll it.

[0013] S13: Cut out the shape of lithium battery electrode sheets from the metal substrate.

[0014] The present invention provides a lithium battery cell, the lithium battery cell comprising: lithium battery electrode sheets as described in any of the above claims; a separator; wherein the lithium battery electrode sheets and the separator are alternately overlapped, the tabs of each two adjacent lithium battery electrode sheets are arranged opposite each other, and the outermost two sides are lithium battery electrode sheets with the tabs arranged opposite each other.

[0015] This invention provides a method for preparing a lithium battery cell, the method comprising the following steps:

[0016] S21: Provide a lithium battery electrode as described in any of the above;

[0017] S22: The lithium battery electrode and separator are alternately stacked.

[0018] This invention provides a lithium battery, the lithium battery comprising: lithium battery electrode sheets as described in any one of the above claims;

[0019] This invention provides a method for preparing a lithium battery, the method comprising the following steps:

[0020] The method for preparing lithium battery electrodes as described in any of the above.

[0021] As described above, the lithium battery electrode of the present invention has the following beneficial effects: Due to the presence of the frame-shaped material ring, the lithium battery electrode can avoid the risk of burrs and punctures in the separator caused by the characteristics of the metal base film and the die during cutting; the frame-shaped material ring encapsulates the battery slurry, greatly reducing the risk of powder shedding from the battery slurry or metal base film; by setting the frame-shaped material ring at the edge of the lithium battery electrode, the insulation effect of the electrode edge is ensured, effectively reducing the K-value of the lithium battery; each lithium battery electrode has the same edge size and shape, and the battery slurry has the same position, size, and shape, which is beneficial for efficiently achieving the alignment standard of positive and negative electrodes during the stacking process of lithium battery cells. Attached Figure Description

[0022] Figure 1 The diagram shown is a schematic diagram of the lithium battery electrode structure of the present invention.

[0023] Figure 2 The diagram shown is a flowchart illustrating the lithium battery electrode preparation method of the present invention.

[0024] Figures 3 to 5 The diagram shows the structural schematics of each step in the lithium battery electrode preparation method of the present invention.

[0025] Figure 6 The diagram shown is a schematic diagram of the lithium battery cell structure of the present invention.

[0026] Figure 7 The diagram shows a flow chart of the lithium battery cell preparation method of the present invention.

[0027] Figure 8 The diagram shown is an exploded view of the lithium battery electrode and separator assembly of the present invention.

[0028] Component designation explanation

[0029] 10 Lithium-ion battery electrode sheets

[0030] 11. Metal base film;

[0031] 12 Frame-shaped material ring

[0032] 13 Battery paste

[0033] 14. Electrode

[0034] 20 Diaphragms

[0035] 30 Lithium-ion battery cells Detailed Implementation

[0036] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0037] Please see Figures 1 to 8 It should be noted that the illustrations provided in this embodiment are only schematic representations of the basic concept of the present invention. Therefore, the illustrations only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0038] Example 1

[0039] like Figures 1 to 3 As shown, this embodiment provides a lithium battery electrode 10, which includes: a metal base film 11; a frame-shaped material ring 12 located above the metal base film 11 for protecting the lithium battery electrode 10; a battery paste 13 located inside the frame-shaped material ring, the thickness of the battery paste 13 being the same as the thickness of the frame-shaped material ring 12; and a tab 14 located on one side of the metal base film 11.

[0040] The shape of the frame-shaped material ring 12 can be any suitable frame shape, such as a square frame, a rhombus frame, or a ring, and can be set according to actual needs; in this embodiment, a square frame shape is preferred, as the square frame material ring is easy to process in the subsequent preparation of battery cells and lithium batteries.

[0041] As an example, the material of the frame-shaped material ring 12 is one or a combination of two of the following: adhesive and ceramic slurry.

[0042] As an example, the frame width of the frame-shaped material ring 12 ranges from 2mm to 5mm, and the thickness ranges from 1μm to 20μm.

[0043] It should be noted that the length and width of the frame-shaped material ring 12 can be set according to the actual size requirements of the lithium battery cell, and no specific limitation is made here.

[0044] The tab 14 can be located at any position on one side of the metal substrate 11. During the fabrication of the lithium battery cell 30, the position of the tab 14 can be consistent. In this embodiment, it is preferable to position the tab 14 at the middle position on one side of the metal substrate 11.

[0045] The lithium battery electrode sheet of the present invention has the following beneficial effects: Due to the presence of the frame-shaped material ring, the characteristics of the metal base film and the die-cutting mold can avoid the risk of burrs forming on the electrode sheet and puncturing the separator during cutting; the frame-shaped material ring encapsulates the battery slurry, greatly reducing the risk of powder shedding from the battery slurry or metal base film; by setting the frame-shaped material ring at the edge of the lithium battery electrode sheet, the insulation effect of the electrode edge is ensured, effectively reducing the K value of the lithium battery; each lithium battery electrode sheet has the same edge size and shape, and the battery slurry has the same position, size, and shape, which is beneficial for efficiently achieving the standard of positive and negative electrode alignment during the stacking process of lithium battery cell manufacturing.

[0046] Example 2

[0047] like Figures 2 to 5 As shown, this invention provides a method for preparing a lithium battery electrode sheet. This method can be used to prepare the lithium battery electrode sheet described in Example 1 above. The following description is in conjunction with the accompanying drawings (e.g., ...). Figures 2 to 5 The preparation method of the lithium battery electrode in this embodiment 2 is described in detail below.

[0048] like Figure 2 and Figure 3 As shown, step S11 is performed first, a metal base film 11 is provided, and a matrix arrangement of frame-shaped material rings 12 is formed on the metal base film 11. The width of the frame-shaped material rings 12 ranges from 3mm to 10mm, and then they are dried.

[0049] like Figure 2 and Figure 4 As shown, step S12 is then performed, in which battery paste 13 is coated inside the frame-shaped material ring 12, dried again, and rolled.

[0050] It should be noted that the battery paste 13 is coated inside the frame-shaped material ring 12, and the thickness of the coating must be the same as that of the frame-shaped material ring 12. After coating, it needs to be dried again and compacted by roller pressing to make it flat. This also releases internal stress and changes possible phenomena such as bulging and delamination, ensuring that the final thickness of the frame-shaped material ring 12 and the battery paste 13 are the same, which helps to save space in the cell manufacturing process. In addition, the battery paste 13 is surrounded by the frame-shaped material ring 12, making them the same size, which helps to efficiently achieve the alignment standard of the positive and negative electrode sheets.

[0051] The drying temperature used in steps S11 and S12 can be adjusted according to the slurry used. The specific temperature is not limited here, as long as the drying effect is achieved.

[0052] like Figure 2 and Figure 5 As shown, the final step is S13, in which the shape of the lithium battery electrode 10 is cut out from the metal substrate 11.

[0053] It should be noted that the tabs 14 of the lithium battery electrode 10 can be cut together from the metal base film 11, or the metal base film 11 can be cut first and then the tabs 14 can be welded to one side of the lithium battery electrode 10. The tabs 14 can be located at any position on one side of the metal base film 11; their positions need to be consistent during the fabrication of the lithium battery cell 30. In this embodiment, the tabs 14 of the lithium battery electrode 10 are preferably cut together from the metal base film 11 and located in the middle of one side of the metal base film 11. This method is relatively simple and avoids the problem of short circuits caused by weak welding.

[0054] In this embodiment, during cutting, a portion of the outer ring of the frame-shaped material ring 12, with a width ranging from 3mm to 10mm, is cut off, leaving a width of 2mm to 5mm. The presence of the frame-shaped material ring 12 largely eliminates the possibility of powder shedding from the battery slurry 13 or the metal substrate 11. Furthermore, burrs on the electrode edge can be straightened under the pressure of the frame-shaped material ring 12 and enclosed within it, preventing burrs on the metal substrate 11 from puncturing the separator 20 during the manufacturing process of the lithium battery chip 30. Simultaneously, the insulation of the metal substrate 11 edge is improved. The lithium battery electrode 10 can be cut from the entire metal substrate 11 one by one using a die, or it can be cut simultaneously using machinery.

[0055] The lithium battery electrode sheet of the present invention has the following beneficial effects: Due to the presence of the frame-shaped material ring, the characteristics of the metal base film and the die-cutting mold can avoid the risk of burrs forming on the electrode sheet and puncturing the separator during cutting; the frame-shaped material ring encapsulates the battery slurry, greatly reducing the risk of powder shedding from the battery slurry or metal base film; by setting the frame-shaped material ring at the edge of the lithium battery electrode sheet, the insulation effect of the electrode edge is ensured, effectively reducing the K value of the lithium battery; each lithium battery electrode sheet has the same edge size and shape, and the battery slurry has the same position, size, and shape, which is beneficial for efficiently achieving the standard of positive and negative electrode alignment during the stacking process of lithium battery cell manufacturing.

[0056] Example 3

[0057] like Figure 6 and Figure 8 As shown, the present invention provides a lithium battery cell 30, the lithium battery cell 30 comprising: lithium battery electrode 10 as described in Embodiment 1; separator 20; the lithium battery electrode 10 and the separator 20 are alternately stacked, the tabs 14 of each two adjacent lithium battery electrodes are arranged opposite to each other, and the outermost two sides are the lithium battery electrode 10 with the tabs 14 arranged opposite to each other.

[0058] In this embodiment, the first layer of the lithium battery cell 30 is the electrode on the right side of the tab 14, serving as the positive electrode; the second layer is the separator 20; the third layer is the electrode on the left side of the tab 14, serving as the negative electrode, and so on (e.g.) Figure 8 (As shown). The number of layers is set according to the actual needs of the lithium battery cell 30, and is not limited here.

[0059] Example 4

[0060] like Figures 6 to 8 As shown, this embodiment provides a method for preparing a lithium battery cell. This method can be used to prepare the lithium battery cell 30 described in Embodiment 3 above. The following description is in conjunction with the accompanying drawings (e.g., ...). Figures 6 to 8 The preparation method of the lithium battery cell 30 in this embodiment 3 is described in detail below.

[0061] like Figure 7 and Figure 8 As shown, step S21 is performed first to provide the lithium battery electrode 10 as described in Example 1. The specific process of preparing the lithium battery electrode 10 has been described in detail in Example 2 above, and will not be repeated here.

[0062] like Figure 7 and Figure 8 As shown, next step S22 is performed, in which the lithium battery electrode 10 and the separator 20 are alternately stacked (e.g., Figure 8 (As shown).

[0063] It should be noted that the tabs 14 of each pair of adjacent lithium battery electrode sheets 10 are arranged opposite each other, and the outermost two sides are the lithium battery electrode sheets 10 with the tabs 14 arranged opposite each other. When stacked alternately, the battery paste 13 of the lithium battery electrode sheets 10 are of the same size, which is beneficial to achieving the alignment standard of positive and negative electrode sheets efficiently.

[0064] Example 5

[0065] This invention provides a lithium battery, which includes a lithium battery electrode 10 as described in Embodiment 1. The structure of the lithium battery electrode 10 has been described in detail in Embodiment 1 above, and will not be repeated here.

[0066] Example 6

[0067] This invention provides a method for preparing a lithium battery, which can be used to prepare the lithium battery cell 30 described in Example 5 above. The method includes the preparation method of the lithium battery electrode 10 as described in Example 2. The specific process of preparing the lithium battery electrode 10 has been described in detail in Example 2 above, and will not be repeated here.

[0068] In summary, the lithium battery electrode of the present invention has the following beneficial effects: Due to the presence of the frame-shaped material ring, the characteristics of the metal base film and the die-cutting mold can avoid the risk of burrs forming on the electrode and puncturing the separator during cutting; the frame-shaped material ring encapsulates the battery slurry, greatly reducing the risk of powder shedding from the battery slurry or metal base film; by setting the frame-shaped material ring at the edge of the lithium battery electrode, the insulation effect of the electrode edge is ensured, effectively reducing the K-value of the lithium battery; each lithium battery electrode has the same edge size and shape, and the position, size, and shape of the battery slurry are also the same, which is beneficial for efficiently achieving the alignment standard of positive and negative electrodes during the stacking process of lithium battery cell manufacturing. Therefore, the present invention effectively overcomes the various shortcomings of the prior art and has high industrial application value.

[0069] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A lithium battery electrode, characterized in that, The lithium battery electrode includes: Metal base film; A frame-shaped material ring, located above the metal base film, is used to protect the lithium battery electrode sheet; the frame-shaped material ring is square in shape; the material of the frame-shaped material ring is one or a combination of two of the following: adhesive and ceramic slurry; the width of the frame-shaped material ring ranges from 2mm to 5mm; and the thickness ranges from 1μm to 20μm. The battery paste is located inside the frame-shaped material ring, and the thickness of the battery paste is the same as the thickness of the frame-shaped material ring; The tab is located in the middle of one side of the metal substrate.

2. A method for preparing a lithium battery electrode, used to prepare the lithium battery electrode as described in claim 1, characterized in that, The preparation method includes: S11: Provide a metal base film, form a matrix of frame-shaped material rings on the metal base film, the width of the frame-shaped material rings is in the range of 3mm to 10mm, and dry; S12: Apply battery paste to the frame-shaped material ring, dry it again, and roll it. S13: Cut out the shape of lithium battery electrode sheets from the metal substrate.

3. A lithium battery cell, characterized in that, The lithium battery cell includes: The lithium battery electrode as described in claim 1; Diaphragm; The lithium battery electrode and the separator are stacked alternately, with the tabs of each two adjacent lithium battery electrodes facing each other, and the outermost two sides being the lithium battery electrodes with the tabs facing each other.

4. A method for preparing a lithium battery cell, characterized in that, The preparation method includes: S21: Provide the lithium battery electrode sheet as described in claim 1; S22: The lithium battery electrode and separator are alternately stacked.

5. A lithium battery, characterized in that, The lithium battery includes: the lithium battery electrode as described in claim 1.

6. A method for preparing a lithium battery, characterized in that, The preparation method includes the preparation method of lithium battery electrode as described in claim 2.

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