A method of drying batteries

Abstract

The invention relates to a cell drying method. The cell drying method comprises the following steps: a closed vertical drying box body is adopted; multiple sets of contact heating units consisting ofupper pressing plates and lower pressing plates are uniformly distributed in each drying cavity; a cell contact heating station is formed between two pressing plates of each set of contact heating units; heating wires are arranged between the upper and lower pressing plates of each contact heating unit, so that cells fed in each contact heating station form corresponding heating units; and in theheating pressed process, the cells are pressed and dried under sealed environment. The cell drying method can accelerate the cell drying speed, can dry products with different specifications, is suitable for large-scale industrial production, overcomes general problems in traditional cell drying equipment, and prevents lower transfer speed of heat in vacuum due to radiation heating.

Description

technical field [0001] The invention relates to the technical field of battery manufacturing, in particular to a battery cell drying method. Background technique [0002] In the manufacturing process of lithium-ion batteries, the formation process of lithium batteries directly affects the capacity, cycle performance, self-discharge performance, and high-temperature performance of the battery. [0003] The battery cell drying process is also an important link that affects battery production efficiency. Lithium-ion batteries need to be dried after cooling to remove moisture inside the pole pieces to ensure battery life and performance. [0004] However, the traditional battery drying process mainly adopts the combined method of thermal radiation heating and low vacuum, and its drying efficiency is low, generally drying for 12 to 70 hours. The low-efficiency drying process prolongs the production cycle of the product and increases the process cost; Heat conduction heating can ...

AI Technical Summary

Problems solved by technology

[0004] However, the traditional battery drying process mainly adopts the combined method of thermal radiation heating and low vacuum, and its drying efficiency is low, generally drying for 12 to 70 hours. The low-efficiency drying process prolongs the production cycle of the product and increases the process cost; Heat conduction heating can also be used for drying, but due to the development of lithium-ion batteries in the direction of high compaction density, high specific surface area of ​​materials, and extremely small gaps between positive and negative electrodes, moisture escapes during the drying process of lithium-ion power batteries Long path, high escape resistance, difficult to improve drying efficiency, and even the problem that the limit water content of drying cannot reach the target value

[0005] The problem that those skilled in the art need to solve is the problem that there is water vapor on the battery cell after the cooling treatment by the manipulator of the battery production equipment. After this process, it is obvious that the battery cell needs to be dried. After reviewing the existing known The key analysis of technical defects found that the principle of the traditional cell drying process is to put the cell into the heating box, generate heat through the radiation in the box, and then extract the air in the heating box to reach a vacuum state. This kind of drying treatment, the heat transfer in vacuum is slow, the drying treatment efficiency is low, and it is not suitable for large-scale industrial production

[0006] At present, although many traditional battery drying equipment adopt the unified radiation and unified heating method, it still cannot ensure that each battery cell can achieve the ideal drying degree, which has a great impact on the battery drying process.

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