Coated composite pole piece strip

Abstract

The utility model provides a coated composite pole piece strip. The coated composite pole piece strip comprises: a strip-shaped electrode layer having a first surface and a second surface opposite to the first surface and having a width of 20-1200 mm and a thickness of 3-12 [mu] m; the first active material layer is positioned on the first surface of the electrode layer, the second active material layer is positioned on the second surface of the electrode layer, the first active material layer is a continuous layer with uniform thickness, the second active material layer is an intermittent layer, the intermittent layer comprises a plurality of parts which are spaced from one another, the length and width of each part are 20-1000mm, and the length and width of each part are 20-1000mm. The distance between every two adjacent parts is 0.5 to 100 mm; the solid-state electrolyte layer is positioned on one side, far away from the electrode layer, of the second active material layer; the length and width of the solid-state electrolyte layer are at least greater than those of each part of the second active material layer; and the solid-state electrolyte layer completely covers the second active material of each part.

Description

Technical Field

[0001] The utility model relates to the technical field of energy storage, and in particular to a coated composite pole piece strip material that can be used for solid-state batteries. Background Art

[0002] Solid-state batteries are a new type of battery technology that focuses on the application and improvement of solid electrolytes and the innovation of the overall battery structure. Compared with traditional liquid batteries, they have significant advantages in terms of safety, energy density and cycle life.

[0003] Patent CN107452985B discloses a solid-state battery manufacturing method, wherein multiple layers of collector, positive electrode mixture, solid electrolyte and negative electrode mixture are stacked to obtain a stacked battery with two end faces and side faces in the stacking direction. In order to avoid short circuit between positive and negative electrodes, it is also necessary to inject resin into the side of the stacked battery through a complex process to play an insulating role. The production cost is high and the production process needs to be further optimized. Summary of the invention

[0004] To address these problems, the utility model provides a coated composite electrode strip. The area on the coated composite electrode strip where the second active material layer is completely coated by the solid electrolyte layer can be cut off and used as an electrode, which is then stacked to form a solid-state battery electrode, fundamentally solving the problem of short circuit between the positive and negative electrodes and greatly simplifying the solid-state battery production process.

[0005] To achieve the above object, the utility model provides a coated composite pole piece strip, the coated composite pole piece strip comprising:

[0006] A strip-shaped electrode layer, the electrode layer having a first surface and a second surface opposite thereto, the electrode layer having a width of 20-1200 mm and a thickness of 3-20 μm;

[0007] a first active material layer and a second active material layer respectively disposed on a first surface and a second surface of the electrode layer; the first active material layer is one of a positive electrode active material and a negative electrode active material; the second active material layer is the other of a positive electrode active material and a negative electrode active material; the first active material layer is a continuous layer with uniform thickness, and the second active material layer is an intermittent layer including a plurality of portions spaced apart from each other; and

[0008] The solid electrolyte layer is located on a side of the second active material layer away from the electrode layer and on an area on the second surface of the electrode layer not covered by the second active material layer, so as to completely cover the second active material layer.

[0009] In the context of the present invention, the electrode layer may also be referred to as the current collector layer, and both have the same meaning.

[0010] Optionally, the first active material layer has a thickness of 2-50 μm.

[0011] Optionally, the width of the first active material layer is not greater than the width of the electrode layer, and is preferably the same as the width of the electrode layer.

[0012] Optionally, the intermittent layer of the second active material layer comprises a plurality of parts.

[0013] Optionally, each part of the intermittent layer is in the shape of a rectangle, and the length and width of the rectangle are 20-1000 mm.

[0014] Optionally, each part of the intermittent layer is circular in shape, and the diameter of the circle is 5-100 mm.

[0015] Optionally, the spacing distance between the multiple parts of the intermittent layer is 0.5-100 mm.

[0016] Optionally, the solid electrolyte layer is a continuous layer, completely covering the second active material layer and the area on the electrode layer that is not covered by the second active material layer.

[0017] Optionally, the solid electrolyte layer is an intermittent layer, which includes a plurality of parts spaced apart from each other, and each part is larger than a size of each part of the second active material layer and completely covers the second active material layer.

[0018] Optionally, the solid electrolyte includes an inorganic solid electrolyte (such as an oxide solid electrolyte, a sulfide solid electrolyte), a polymer solid electrolyte, or a composite electrolyte (such as a composite electrolyte of an oxide and a polymer).

[0019] Optionally, the polymer electrolyte material includes lithium polyacrylate (LiPAA), polyethylene glycol (PEO) and an electrolyte formed by a composite thereof with a lithium salt.

[0020] The wrapped composite pole piece strip of the utility model can be applied to solid-state batteries after cutting. For example, the strip of the utility model is cut from the intermittent part of the second active material layer to form a wrapped composite pole piece after cutting. The first active material layer on the wrapped composite pole piece has the same size as the electrode layer, and the solid electrolyte layer completely covers the second active material layer.

[0021] The battery cell formed by stacking the coated composite pole pieces can avoid internal short circuit between the first active material layer and the second active material layer, greatly reducing the complexity of the battery production process and improving battery safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the coated composite pole piece strip of the utility model.

[0023] Figure 2 yes Figure 1 Schematic diagram of the cross section of the mid-coated composite pole piece strip.

[0024] Figure 3 It is a schematic diagram of a specific embodiment of the coated composite pole piece strip of the utility model.

[0025] Figure 4 It is a schematic diagram of another specific embodiment of the coated composite pole piece strip of the utility model.

[0026] Description of the figure number:

[0027] 1 coated composite pole piece strip 10 electrode layer 11 first active material layer 12 second active material

[0028] 13 solid electrolyte layer 11' negative electrode active material 11" positive electrode active material

[0029] 12' positive electrode active material 12" negative electrode active material DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solution and advantages of the utility model more clear, the utility model is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the utility model and are not used to limit the utility model.

[0031] Figure 1 This is a schematic diagram of the coated composite pole piece strip of the utility model. Figure 2 yes Figure 1 Schematic diagram of the cross section of the coated composite pole piece strip. Figure 1 and Figure 2 As shown, the coated composite electrode strip 1 is composed of an electrode layer 10, a first active material layer 11, a second active material layer 12 and a solid electrolyte layer 13. The first active material layer 11 is located on one side of the electrode layer 10 and is a continuous and uninterrupted material layer; the second active material layer 12 is located on the other side of the electrode layer 10 opposite to the first active material layer 11, and the second active material layer 12 is intermittent at least along the length direction of the strip; the second active material layer 12 has an opposite polarity to the first active material layer 11, that is, when the first active material layer 11 is a positive electrode material, the second active material 12 is a negative electrode material; when the first active material layer 11 is a negative electrode material, the second active material layer 12 is a positive electrode material. The second active material layer 12 is also covered with a solid electrolyte layer 13 on the side away from the electrode layer 10, and the solid electrolyte layer 13 completely covers the second active material layer 12.

[0032] Figure 3The figure shows a specific embodiment of the coated composite electrode strip of the utility model. In this embodiment, the second active material is a positive electrode active material 12', and the first active material is a negative electrode active material 11'. The positive electrode active material 12' and the negative electrode active material 11' are respectively located on the two sides of the electrode layer 10, the area of ​​the positive electrode active material 12' is smaller than the area of ​​the negative electrode active material 11', and the solid electrolyte layer 13 completely covers the positive electrode active material 12'.

[0033] Figure 4 Another specific embodiment of the coated composite electrode strip of the utility model is shown. In this embodiment, the second active material is a negative electrode active material 12", and the first active material is a positive electrode active material 11". The negative electrode active material 12" and the positive electrode active material 11" are respectively located on the two sides of the electrode layer 10, the area of ​​the negative electrode active material 12" is smaller than the area of ​​the positive electrode active material 11", and the solid electrolyte layer 13 completely covers the negative electrode active material 12".

[0034] It should be understood that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A coated composite pole piece strip, characterized in that: The coated composite pole piece strip comprises: A strip-shaped electrode layer, the electrode layer having a first surface and a second surface opposite thereto, the electrode layer having a width of 20-1200 mm and a thickness of 3-20 μm; A first active material layer and a second active material layer are respectively located on a first surface and a second surface of the electrode layer; the first active material layer is one of a positive electrode active material and a negative electrode active material; the second active material layer is the other of a positive electrode active material and a negative electrode active material; the first active material layer is a continuous layer with uniform thickness, and the second active material layer is an intermittent layer, and the intermittent layer includes a plurality of parts spaced apart from each other; and The solid electrolyte layer is located on a side of the second active material layer away from the electrode layer and on an area on the second surface of the electrode layer not covered by the second active material layer, so as to completely cover the second active material layer.

2. The coated composite pole piece strip according to claim 1, characterized in that: The thickness of the first active material layer is 2-50 μm.

3. The coated composite pole piece strip according to claim 1, characterized in that: The width of the first active material layer is not greater than the width of the electrode layer.

4. The coated composite pole piece strip according to claim 1, characterized in that: Each part of the intermittent layer is in the shape of a rectangle, and the length and width of the rectangle are 20-1000 mm.

5. The coated composite pole piece strip according to claim 4, characterized in that: Each part in the intermittent layer is circular in shape, and the diameter of the circle is 5-100 mm.

6. The coated composite pole piece strip according to claim 1, characterized in that: The spacing distance between the multiple parts of the intermittent layer is 0.5-100 mm.

7. The coated composite pole piece strip according to claim 1, characterized in that: The solid electrolyte layer is a continuous layer, which completely covers the second active material layer and the area on the electrode layer that is not covered by the second active material layer.

8. The coated composite pole piece strip according to claim 1, characterized in that: The solid electrolyte layer is an intermittent layer, the intermittent layer includes a plurality of portions spaced apart from each other, and a size of each portion is larger than a size of each portion of the second active material layer and completely covers the second active material layer.

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