Preparation method of secondary battery and secondary battery

Abstract

The invention provides a preparation method of a secondary battery and the secondary battery. The preparation method comprises the following steps: putting a battery core into a battery shell, and baking; after baking is completed, injecting an electrolytic solution into the battery shell, wherein two corresponding ends of the battery shell are respectively provided with a first liquid injection port and a second liquid injection port, the first liquid injection port is connected with a first electrolytic solution storage end, the second liquid injection port is connected with the first vacuumizing end, an electrolytic solution in the first electrolytic solution storage end is pumped to the second liquid injection port from the first liquid injection port by the first vacuumizing end; andafter the liquid injection is completed, sealing the first liquid injection port and the second liquid injection port to complete the preparation of the secondary battery. Compared with the prior art,the preparation method provided by the invention has the advantages that an electrolytic solution is introduced into a battery shell in a manner of arranging liquid injection ports at two ends and pumping the electrolytic solution from the liquid injection port at one end to the liquid injection port at the other end, so that the electrolytic solution penetrates through the cross section of the whole electrode sheet in the injection process, the contact area of the electrolytic solution and the electrode sheet is increased, and the problem of electrolytic solution absorption is solved.

Description

technical field [0001] The invention relates to the field of lithium batteries, in particular to a preparation method of a secondary battery and the secondary battery. Background technique [0002] With the vigorous development of the current new energy industry, it has become the common goal of everyone in the industry to continuously increase the energy density of batteries to increase the standby time and cruising range of electronic products. Some lithium-ion battery manufacturers increase energy density by using high-energy-density silicon series materials; although silicon series materials are of great help to the improvement of energy density, their cycle performance is still very large compared with graphite-based negative electrode materials. difference. At the same time, graphite material manufacturers also increase the compaction density of graphite by continuously optimizing graphite material particles and surface morphology, thereby increasing the overall batte...

AI Technical Summary

Problems solved by technology

Some lithium-ion battery manufacturers increase energy density by using high-energy-density silicon series materials; although silicon series materials are of great help to the improvement of energy density, their cycle performance is still very large compared with graphite-based negative electrode materials. difference

At the same time, graphite material manufacturers also increase the compaction density of graphite by continuously optimizing graphite material particles and surface morphology, thereby increasing the overall battery energy density; but with the continuous improvement of graphite compaction density, the porosity of the pole piece It is getting smaller and smaller, which makes it very difficult to absorb liquid in the liquid injection process in the production process of lithium-ion batteries, which affects the energy density of the battery

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