High-capacity solid sodium ion multi-tab pole piece and battery cell thereof

Abstract

The utility model relates to a high-capacity solid sodium ion multi-tab pole piece and a battery cell thereof. The utility model relates to a high-capacity solid sodium ion multi-tab pole piece which comprises a positive pole piece and a negative pole piece, the positive plate is provided with a plurality of positive tabs, a gap is formed between every two adjacent positive tabs, and the positive plate or the negative plate is provided with a positioning groove; the negative plate is provided with a plurality of negative tabs, and a gap is formed between every two adjacent negative tabs. The utility model has the effect that the production stability can be improved.

Description

Technical Field

[0001] The utility model relates to a large-capacity solid-state sodium ion multi-electrode pole piece and a battery core thereof. Background Art

[0002] With the application of sodium-ion batteries in large-scale energy storage, the capacity of single cells is getting larger and larger, and the power needs to be larger and larger. When the cell pole pieces become larger, because the absolute charge and discharge current is huge, the cell tabs must be able to bear the overload capacity of large currents without generating heat. For the lamination process, if the tabs are on the same side of the pole pieces, electrons will be transferred along the shortest distance between the positive and negative pole tabs due to space constraints, which will affect the capacity released by the cell, especially at high-rate charge and discharge, where the temperature rise effect is very obvious. In order to solve this problem, someone proposed the concept of full tabs, but for large sizes with pole piece lengths of 1000 to 2000 MM, parallelism and welding positioning are difficult to control. The present invention innovates the discharge method of the positive and negative tabs, which solves this problem very well. Although sodium batteries and lithium batteries have many similarities, they differ greatly in the negative electrode current collector and negative electrode tab. Due to the potential, sodium ion batteries, especially semi-solid sodium batteries, use the same negative electrode current collector as the positive electrode current collector, which is aluminum foil. The negative electrode tab is also made of aluminum foil and selant as the positive electrode tab. This makes it easy to confuse them during production and difficult to distinguish. The present invention solves this problem very well. The positive and negative tabs of the combined battery pack are fixed, positioned, and distinguished by slots, which facilitates welding. The present invention solves the problem of large-scale production stability of large-capacity sodium ion solid-state batteries. Utility Model Content

[0003] One purpose of the present invention is to solve or alleviate the above technical problems.

[0004] The method adopted by the present invention is to provide a large-capacity solid-state sodium ion multi-electrode electrode sheet, which includes a positive electrode sheet and a negative electrode sheet; the positive electrode sheet is provided with multiple positive electrode ears, and a gap is provided between two adjacent positive electrode ears, and the positive electrode sheet or the negative electrode sheet is provided with a positioning groove; the negative electrode sheet is provided with multiple negative electrode ears, and a gap is provided between two adjacent negative electrode ears.

[0005] According to a further technical solution, the positive electrode sheet includes ternary sodium.

[0006] In a further technical solution, the negative electrode sheet includes hard carbon.

[0007] A large-capacity solid-state sodium-ion battery cell comprises the large-capacity solid-state sodium-ion multi-electrode tabs described above, and also comprises a diaphragm and an aluminum-plastic film; the positive electrode sheets and the negative electrode sheets are stacked in sequence, and a diaphragm is provided between adjacent positive electrode sheets and negative electrode sheets; the positive electrode tabs and the negative electrode tabs are arranged opposite to each other and are both exposed from the diaphragm; the aluminum-plastic film surrounds the positive electrode sheets, the negative electrode sheets and the diaphragm, and an electrolyte comprising sodium hexafluorophosphate and an organic solvent is provided in the aluminum-plastic film.

[0008] According to a further technical solution, there is one less positive electrode sheet than the negative electrode sheet.

[0009] According to a further technical solution, a separator is provided on the outside of the outermost negative electrode sheet.

[0010] According to a further technical solution, the diaphragm is a single piece.

[0011] The above technical solution was used to create BT120888699, with a capacity of 600Ah, a top seal length of 1200mm, and a width of 10mm. The conventional method uses 868mm*8mm tabs, while the present invention uses two 430mm*8mm tabs with an 8mm gap between them. The top seal packaging effect was tested in the following table. A comparison of the tab structure of the present invention with that of the non-present invention reveals the following performance.

[0012] Case Patented product of this invention No invention patent required Top seal thickness qualification rate 99.9％ 99％ Top seal short circuit qualified rate 99.9％ 98％ Top head parallelism debugging rate Adjust once every 7 days Debug once a day Production continuity high generally

[0013] The effect achieved by the utility model is that production stability can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a front view schematic diagram of the positive electrode sheet 1 of an embodiment of the present utility model.

[0015] Figure 2 It is a front view schematic diagram of the negative electrode sheet 2 of an embodiment of the present utility model.

[0016] Figure 3 This is a front view schematic diagram of the positive electrode sheet 1 and the negative electrode sheet 2 placed together in an embodiment of the present invention, and the figure is used for comparing the positive electrode sheet 1 and the negative electrode sheet 2.

[0017] Figure 4 It is a schematic front view of the positive electrode sheet 1, the negative electrode sheet 2, and the separator 3 after being stacked in an embodiment of the present utility model.

[0018] Figure 5 It is a schematic front view of the positive electrode sheet 1, the negative electrode sheet 2, and the separator 3 after being stacked in an embodiment of the present utility model.

[0019] Figure 6 It is a front view schematic diagram of a cutaway aluminum-plastic film 5 of a large-capacity solid-state sodium ion battery cell according to an embodiment of the present utility model.

[0020] Designate the drawings in the specification Figure 6 The following is an abstract.

[0021] Positive electrode sheet 1; positive electrode ear 11; positioning groove 111; negative electrode sheet 2; negative electrode ear 21; separator 3; aluminum-plastic film 5. DETAILED DESCRIPTION

[0022] The specific implementation of the present invention will be described below with reference to the accompanying drawings.

[0023] As a specific embodiment, the large-capacity solid-state sodium ion multi-electrode tab of the embodiment of the present invention includes a positive electrode sheet 1 and a negative electrode sheet 2, and the positive electrode sheet 1 or the negative electrode sheet 2 is provided with a positioning groove 111. It is convenient to distinguish the positive electrode sheet 1 and the negative electrode sheet 2 and to achieve positioning, and it can also improve production stability.

[0024] The positioning groove 111 is 2*111 mm.

[0025] The positive electrode sheet 1 is provided with a plurality of positive electrode tabs 11, and a gap is provided between two adjacent positive electrode tabs 11. The positive electrode sheet 1 comprises ternary sodium, and other specific components and structures are conventional.

[0026] The negative electrode sheet 2 is provided with a plurality of negative electrode tabs 21, and a gap is provided between two adjacent negative electrode tabs 21. The negative electrode sheet 2 comprises hard carbon, and other specific components and structures are conventional.

[0027] The large-capacity solid-state sodium ion battery cell further includes a diaphragm 3 and an aluminum-plastic film 5.

[0028] The positive electrode sheets 1 and the negative electrode sheets 2 are stacked in sequence, and a separator 3 is provided between adjacent positive electrode sheets 1 and negative electrode sheets 2. For example, there are two positive electrode sheets 1 and three negative electrode sheets 2.

[0029] The positive electrode tab 11 and the negative electrode tab 21 are arranged opposite to each other and are both exposed from the separator 3 , that is, the positive electrode tab 11 faces upward and the negative electrode tab 21 faces downward.

[0030] The aluminum-plastic film 5 surrounds the positive electrode sheet 1 , the negative electrode sheet 2 and the separator 3 , and an electrolyte including sodium hexafluorophosphate and an organic solvent is provided in the aluminum-plastic film 5 .

[0031] As one specific embodiment, the number of positive electrode sheets 1 is less than the number of negative electrode sheets 2 .

[0032] As one of the specific embodiments, a separator 3 is provided outside the outermost negative electrode sheet 2 .

[0033] As one of the specific implementations, the diaphragm 3 is a single piece.

Claims

1. Large capacity solid sodium ion multi-electrode ear piece, characterized by: It comprises a positive electrode sheet (1) and a negative electrode sheet (2); the positive electrode sheet (1) is provided with a plurality of positive electrode ears (11), and a gap is provided between two adjacent positive electrode ears (11); the positive electrode sheet (1) or the negative electrode sheet (2) is provided with a positioning groove (111); the negative electrode sheet (2) is provided with a plurality of negative electrode ears (21), and a gap is provided between two adjacent negative electrode ears (21).

2. The large-capacity solid-state sodium ion multi-electrode ear pole piece according to claim 1 is characterized in that: The positive electrode sheet (1) includes ternary sodium.

3. The large-capacity solid-state sodium ion multi-electrode ear pole piece according to claim 1 is characterized in that: The negative electrode sheet (2) includes hard carbon.

4. A large-capacity solid-state sodium ion battery cell, comprising the large-capacity solid-state sodium ion multi-electrode pole piece according to any one of claims 1 to 3, characterized in that: The invention also comprises a diaphragm (3) and an aluminum-plastic film (5); the positive electrode sheet (1) and the negative electrode sheet (2) are stacked in sequence, and a diaphragm (3) is arranged between adjacent positive electrode sheets (1) and negative electrode sheets (2); the positive electrode ear (11) and the negative electrode ear (21) are arranged opposite to each other and are both exposed from the diaphragm (3); the aluminum-plastic film (5) surrounds the positive electrode sheet (1), the negative electrode sheet (2) and the diaphragm (3), and an electrolyte comprising sodium hexafluorophosphate and an organic solvent is arranged in the aluminum-plastic film (5).

5. The large-capacity solid-state sodium ion battery cell according to claim 4, characterized in that: The number of positive electrode sheets (1) is one less than that of negative electrode sheets (2).

6. The large-capacity solid-state sodium ion battery cell according to claim 5, characterized in that: A diaphragm (3) is arranged outside the outermost negative electrode sheet (2).

7. The large-capacity solid-state sodium ion battery cell according to claim 6 is characterized in that: The diaphragm (3) is a single piece.

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