Nanocomposite gel electrolyte, lithium secondary battery and preparation method of lithium secondary battery

Abstract

The invention relates to nanocomposite gel electrolyte, a lithium secondary battery and a preparation method of the lithium secondary battery. The gel electrolyte is prepared by the steps: introducinghydrophobic modified nanoparticles into liquid electrolyte, and forming a three-dimensional network by using hydrogen-bond interaction among the hydrophobic modified nanoparticles and surface modified molecules thereof and electrolyte solvent molecules, so as to enable gelation of the liquid electrolyte. The ionic conductivity of the gel electrolyte is close to that of electrolyte of the same type and is about 10<-3> S / cm. According to the addition of the hydrophobic modified nanoparticles, the lithium-ion transference number of the electrolyte can be effectively improved, and the interface impedance between the electrolyte and the lithium metal is reduced. In addition, compared with the pure electrolyte of the same type, the gel electrolyte has excellent compatibility with a lithium metal electrode and good cycling stability. The gel electrolyte can be compounded onto the diaphragm in a direct coating or coating swelling method, the preparation process is simple, and convenient production is facilitated.

Description

technical field [0001] The invention relates to the field of lithium metal secondary batteries, in particular to a nanocomposite gel electrolyte, a lithium secondary battery and a preparation method thereof. Background technique [0002] With the development of society, more and more people pay attention to environmental protection and energy saving. Lithium-ion batteries have become one of the most popular chemical energy sources due to their high energy density, long cycle life, and low environmental impact. Lithium-ion batteries have had a profound impact on people's daily lives. Commercially used carbon-negative lithium-ion batteries are now basically close to their theoretical capacity, which is difficult to meet the increasingly high demands of portable electronic devices, electric vehicles, and large-scale energy storage. application requirements. Therefore, batteries with higher energy density and safety are still urgently needed. [0003] Lithium metal has the hi...

AI Technical Summary

Problems solved by technology

However, there are still big problems when lithium metal is directly used as the negative electrode of the battery.

These problems include: poor cycle and rate performance, safety is difficult to guarantee

However, the poor contact between the solid electrolyte and the electrode will generate a large interface resistance, which is not conducive to the performance of the solid electrolyte.

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