Soft pack lithium ion battery and manufacturing method of same

Abstract

The invention relates to a soft pack lithium ion battery including a cell assembly and a soft pack shell. The cell assembly comprises a plurality of single cell bodies, which are connected in parallel. Each single cell body is a coiled-type cell body. The thickness of the cell assembly is larger than 1 cm. The coiled-type cell body is higher in production efficiency and lower in production cost. Due to the structure that the single cell bodies are stacked in a parallel-connected manner, a problem of high internal resistance of the coiled-type cell body can be avoided. The structure also solves a problem of poor flatness frequently appearing in charge/discharge process of a thick coiled cell structure in later period, wherein the thickness of the cell assembly is larger than 1 cm when the single cell bodies are connected in parallel, so that the cell assembly is higher in capacity. The soft pack lithium ion battery is high in production efficiency and low in production cost, has high energy density, large capacity, and is improved in large-current charge/discharge performance. The invention also discloses a manufacturing method of the soft pack lithium ion battery.

Description

technical field [0001] The invention relates to the technical field of lithium-ion battery production, in particular to a soft-pack lithium-ion battery and a manufacturing method thereof. Background technique [0002] Compared with cylindrical batteries and aluminum-cased square batteries, soft-pack lithium-ion batteries using aluminum-plastic films have the characteristics of simple structure, small size, light weight, shape can be changed according to needs, high energy density, and high safety. Its application range is more and more extensive, and the demand is also increasing. [0003] The application of lithium-ion batteries in the field of energy storage has developed rapidly. The main applications of the energy storage market are in the field of renewable energy grid connection, distributed power generation and micro-grid. Household energy storage has also developed into a popular application abroad. In the field of micro-grid and the field of household energy storag...

AI Technical Summary

Problems solved by technology

[0004] As we all know, the current large-capacity pouch battery generally adopts the laminated production method: that is, the die-cut positive and negative electrodes and the separator are laminated together, which is characterized by low internal resistance and suitable for high-current discharge, but its disadvantages The process is complicated, the production cost is high, the stacking efficiency is low, the performance consistency is poor, and it is difficult to ensure the flatness of the battery cell in the subsequent charge and discharge, thus affecting the cycle life

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