Electrode structure, battery and manufacturing method of electrode structure

Abstract

The invention discloses an electrode structure, a battery and a manufacturing method of the electrode structure, the electrode structure comprises a current collector and an active layer, and the active layer is arranged on one surface of the current collector; the active layer comprises a plurality of active parts, the active parts are all arranged on the current collector, and an interval is formed between every two adjacent active parts; the active part comprises a first part and a second part, the first part is connected with the current collector, the second part is connected with the first part, and the projection area of the second part on the surface is larger than that of the first part on the surface. Through application of the electrode structure, the internal stress and the bending moment of the electrode can be effectively reduced during winding through the T-shaped active parts which are arranged at intervals, expansion force brought by expansion of the electrode active layer is resisted, and therefore cracking of the electrode is reduced; and the contact area with the electrolyte is increased through the interval arrangement, so that the ion diffusion path is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of batteries, and in particular to an electrode structure, a battery, and a method for manufacturing the electrode structure. Background Art

[0002] Currently, the production of cylindrical batteries often involves the production of electrodes and subsequent winding processes. Winding creates a certain amount of bending moment in the electrodes, which can easily lead to surface cracks. Furthermore, during battery cycling, the expansion force generated by the active material in the electrodes can also easily cause cracking. This directly impacts battery quality and service life.

[0003] Furthermore, improving the lithium-ion transport pathway within existing electrode structures is a topic of intense research in this field. For example, existing Chinese patent CN202111446942.9 considers adding grooves to the electrode surface. However, considering the aforementioned cracking issue, the design of these grooves requires further refinement. Summary of the Invention

[0004] In view of this, and to solve the above problems, the present invention aims to provide an electrode structure comprising: a current collector and an active layer, wherein the active layer is disposed on a surface of the current collector; the active layer comprises: a plurality of active portions, each of the active portions being disposed on the current collector, with a gap formed between each two adjacent active portions;

[0005] The active portion includes a first portion and a second portion, the first portion is connected to the current collector, the second portion is connected to the first portion, and a projected area of ​​the second portion on the surface is larger than a projected area of ​​the first portion on the surface.

[0006] In another preferred embodiment, the active portion has a T-shaped cross section along a direction perpendicular to the surface.

[0007] In another preferred embodiment, a plurality of the active portions are evenly arranged on the surface.

[0008] In another preferred embodiment, the plurality of active portions are arranged in an array structure of multiple rows and columns.

[0009] In another preferred embodiment, the array structure is arranged on the surface in a rectangular shape.

[0010] In another preferred embodiment, the second part is arranged in a rectangular structure.

[0011] In another preferred embodiment, a portion of the interval is disposed between two adjacent first portions, and another portion of the interval is disposed between two adjacent second portions.

[0012] In another preferred embodiment, the spacer is adjacent to the surface.

[0013] The object of the present invention is to provide a battery comprising any one of the electrode structures described above.

[0014] The present invention also aims to provide a method for manufacturing an electrode structure, comprising:

[0015] Step S1, mixing the active material, the conductive agent and the binder to obtain a semi-solid slurry;

[0016] Step S2 , forming the semi-solid slurry on the current collector to form a plurality of active portions.

[0017] Due to the adoption of the above technical solution, the present invention has the following positive effects compared with the prior art:

[0018] Through the application of the present invention, an electrode structure with spaced T-shaped features is provided. By setting a number of T-shaped active parts at intervals, the internal stress and bending moment of the electrode can be effectively reduced during winding, and the expansion force caused by the expansion of the electrode active layer can be resisted, thereby reducing the cracking of the electrode; in addition, the contact area with the electrolyte is increased by the spacing, thereby improving the ion diffusion path, making the electrode reaction more uniform, and thus improving the electrochemical performance of the battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is an overall schematic diagram of an electrode structure of the present invention;

[0020] Figure 2 is a cross-sectional schematic diagram of an electrode structure of the present invention;

[0021] Figure 3 This is a schematic diagram of the winding of an electrode structure of the present invention.

[0022] In the attached figure:

[0023] 1. Current collector; 2. Active layer; 3. Surface; 4. Active portion; 5. Spacer; 6. First portion; 7. Second portion. DETAILED DESCRIPTION

[0024] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0025] In the description of the present invention, it should be understood that the orientations or positional relationships indicated by terms such as “upper”, “lower”, “left”, “right”, “inside”, “outside”, “front”, “back”, “horizontal” and “vertical” are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention, rather than indicating or implying that the device or component referred to must have a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0026] like Figures 1 to 3 FIG. 1 shows an electrode structure of a preferred embodiment, comprising: a current collector 1 and an active layer 2, wherein the active layer 2 is disposed on a surface 3 of the current collector 1; the active layer 2 comprises: a plurality of active portions 4, each of which is disposed on the current collector 1, with a spacer 5 formed between each pair of adjacent active portions 4. Furthermore, the provision of the spacer 5 separates adjacent active portions 4 from each other, thereby reducing internal stress and bending moment generated during winding. Furthermore, during battery cycling, the spacer 5 allows adjacent active portions 4 to undergo a certain amount of expansion and deformation, and preferably prevents the adjacent active portions 4 from directly contacting each other even after expansion.

[0027] Furthermore, as a preferred embodiment, the above-mentioned surface 3 is preferably the outer surface 3 of the current collector 1, and the surface 3 is preferably arranged in a rectangular shape.

[0028] Furthermore, as a preferred embodiment, the active portion 4 includes: a first portion 6 and a second portion 7, the first portion 6 being connected to the current collector 1, the second portion 7 being connected to the first portion 6, and the projected area of ​​the second portion 7 on the surface 3 being larger than the projected area of ​​the first portion 6 on the surface 3. Furthermore, by configuring the first portion 6 to be smaller than the second portion 7, the gap 5 has a larger clearance dimension at a position close to the surface 3 of the current collector 1, that is, the surface areas of the active portion 4 and the current collector 1 at the gap 5 are both increased, so that after the electrolyte enters the gap 5, it can contact the active layer 2 and the current collector 1 with a larger area.

[0029] Furthermore, as a preferred embodiment, the cross section of the active portion 4 along a direction perpendicular to the surface 3 is arranged in a T-shape.

[0030] Furthermore, as a preferred embodiment, a plurality of active portions 4 are evenly arranged on the surface 3 .

[0031] Furthermore, as a preferred embodiment, the active portions 4 are arranged in a multi-row and multi-column array structure. Furthermore, the aforementioned gaps 5 are provided between adjacent active portions 4 in a row and between adjacent active portions 4 in a column.

[0032] Furthermore, as a preferred embodiment, in the above array structure, the intersection of rows and columns is arranged in a cross-shaped interval 5, and the cross-shaped interval 5 includes a small cross-shaped interval part with a smaller upper size and a large cross-shaped interval part with a larger lower size.

[0033] Furthermore, as a preferred embodiment, the array structure is arranged on the surface 3 in a rectangular shape.

[0034] Furthermore, as a preferred embodiment, the second portion 7 is configured in a rectangular structure.

[0035] Furthermore, as a preferred embodiment, a portion of the spacer 5 is disposed between two adjacent first portions 6 , and another portion of the spacer 5 is disposed between two adjacent second portions 7 .

[0036] Furthermore, as a preferred embodiment, the spacer 5 is in contact with the surface 3. Furthermore, the spacer 5 is provided so that at least a portion of the surface 3 is in direct contact with the electrolyte, that is, the surface 3 is connected to the outside of the active layer 2 through the spacer 5.

[0037] Furthermore, as a preferred embodiment, the spacer 5 is arranged in an inverted T-shaped structure.

[0038] The above descriptions are merely preferred embodiments of the present invention and are not intended to limit the implementation and protection scope of the present invention.

[0039] The present invention also has the following implementation modes based on the above:

[0040] A battery comprises any one of the above electrode structures.

[0041] In a further embodiment of the present invention, the positive electrode sheet and / or the negative electrode sheet inside the battery adopts the above-mentioned electrode structure.

[0042] A method for manufacturing an electrode structure according to any one of the above, comprising: step S1, mixing an active material, a conductive agent and a binder in a certain proportion to obtain a semi-solid slurry, which is used to form an active portion 4; step S2, forming the semi-solid slurry on a current collector 1 to form a plurality of active portions 4.

[0043] In a further embodiment of the present invention, in step S2, the semi-solid slurry obtained in step S1 is first injected into the printing syringe of the 3D printing device, and then a plurality of active portions 4 with T-shaped features are printed on the current collector 1 in an intermittent printing manner.

[0044] In a further embodiment of the present invention, in step S2 , a mold is first pre-configured on the current collector 1 , and then the semi-solid slurry obtained in step S1 is injected into the mold so that the semi-solid slurry is bonded to the current collector 1 .

[0045] In a further embodiment of the present invention, the mold has an injection cavity with a T-shaped feature.

[0046] The above description is only a preferred embodiment of the present invention and does not limit the implementation mode and protection scope of the present invention. For those skilled in the art, it should be aware that all solutions obtained by equivalent substitutions and obvious changes made using the description and illustrations of the present invention should be included in the protection scope of the present invention.

Claims

1. An electrode structure, characterized in that: include: A current collector and an active layer, wherein the active layer is disposed on a surface of the current collector; the active layer comprises: a plurality of active portions, each of which is disposed on the current collector, and a gap is formed between each two adjacent active portions; The active portion includes: a first part and a second part, the first part is connected to the current collector, the second part is connected to the first part, and the projection area of ​​the second part on the surface is larger than the projection area of ​​the first part on the surface.

2. The electrode structure according to claim 1, characterized in that: The active portion has a T-shaped cross section along a direction perpendicular to the surface.

3. The electrode structure according to claim 1, characterized in that: A plurality of active parts are evenly arranged on the surface.

4. The electrode structure according to claim 1, characterized in that: The active parts are arranged in an array structure of multiple rows and columns.

5. The electrode structure according to claim 4, characterized in that: The array structure is rectangular and arranged on the surface.

6. The electrode structure according to claim 1, characterized in that: The second part is arranged in a rectangular structure.

7. The electrode structure according to claim 1, characterized in that: A portion of the interval is disposed between two adjacent first portions, and another portion of the interval is disposed between two adjacent second portions.

8. The electrode structure according to claim 1, characterized in that: The spacer is adjacent to the surface.

9. A battery, characterized in that: The electrode structure comprises any one of claims 1 to 8.

10. A method for manufacturing an electrode structure according to any one of claims 1 to 8, characterized in that: include: Step S1, mixing the active material, the conductive agent and the binder to obtain a semi-solid slurry; Step S2, forming the semi-solid slurry on the current collector to form a plurality of active portions.

Images