Symmetrical battery and preparation method thereof

Abstract

The invention belongs to the technical field of batteries, and particularly relates to a symmetrical battery and a preparation method thereof, and the preparation method comprises the following steps: S1, selecting two working electrodes of the same type, and recording the two working electrodes as a first working electrode and a second working electrode; s2, arranging a metal lithium sheet on at least one surface of the first working electrode or the second working electrode to obtain an adjusting electrode; s3, selecting an isolating membrane, welding a first tab on the adjusting electrode, welding a second tab on the second working electrode, and sequentially stacking the adjusting electrode, the isolating membrane and the second working electrode to assemble a battery cell; and S4, selecting an electrolyte and a shell, loading the battery cell into the shell, enabling the first tab and the second tab to extend out of the shell, injecting the electrolyte into the shell, and sealing, packaging, standing, charging and discharging, degassing and packaging the shell to obtain the symmetrical battery. The preparation method of the symmetric battery is simple and convenient in operation steps, high in efficiency and low in cost, and secondary disassembly and packaging are avoided.

Description

technical field [0001] The invention belongs to the technical field of batteries, in particular to a symmetrical battery and a preparation method thereof. Background technique [0002] Lithium-ion batteries have the advantages of high energy density and long cycle life, and have been widely used in portable electronic products, 3C digital and power vehicles. A lithium-ion battery consists of a positive electrode, a negative electrode, a separator, an electrolyte, and a packaging case. The performance of the positive and negative electrodes has the greatest impact on the overall performance of the battery, so it needs to be evaluated. There are many ways to evaluate the main material, including but not limited to the evaluation of the buckle performance, the evaluation of the basic physical properties, the evaluation of the performance of the pole piece, the evaluation of the performance of the full battery, and so on. The structure of a symmetrical battery is different from...

AI Technical Summary

Problems solved by technology

For example, in patent CN108508067A, the same-sex pole pieces disassembled from the finished lithium-ion battery are assembled into a symmetrical battery for testing and characterization. In patent CN111009688A, a metal lithium electrode is placed between the same-sex electrodes of the measuring sheet, and then the working electrode is adjusted to a specific SOC. The metal lithium is taken out, and the same-sex electrode is packaged; the above methods all need to disassemble the finished battery cell and then reassemble it into a symmetrical battery. - Disassembly-assembly-testing is a multi-step process, which is complicated and inefficient. In addition to easily causing damage to the pole piece during disassembly and multiple packaging, the requirements for the disassembly environment are also high

Patents CN109585932A and CN214957245U have changed the structure of the symmetrical battery, and omitted the process of reassembling after dismantling the cell by setting similar plug-in counter-poles, but the step of secondary packaging is still required

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