Processing technology of lithium ion battery electrolyte

Abstract

The invention discloses a processing technology of a lithium ion battery electrolyte. The lithium ion battery electrolyte comprises a non-aqueous solvent, a conductive lithium salt, an additive A andan additive B, the processing technology comprises the following steps: preparing an additive A, purifying a non-aqueous solvent, adding a conductive lithium salt into the purified non-aqueous solvent, uniformly stirring to obtain a basic electrolyte, adding the additive A and an additive B into the basic electrolyte, and carrying out ultrasonic dispersion to obtain the lithium ion battery electrolyte. Experimental results show that the low-temperature performance and the high-temperature performance of the battery can be improved at the same time in the prepared lithium ion battery electrolyte; gas generated by decomposition of a non-aqueous solvent can be inhibited, and expansion of the battery is reduced; the cycle life of the lithium ion battery can be effectively prolonged, and the cycle stability of the battery is good; the preparation method is simple, efficient, low in raw material cost and suitable for large-scale application.

Description

technical field [0001] The invention relates to the technical field of lithium-ion batteries, in particular to a process for processing electrolytes of lithium-ion batteries. Background technique [0002] In recent years, due to the pressure of environmental pollution and energy shortage, all countries are forced to look for new green, environmentally friendly and sustainable energy sources. The high-energy and environmentally friendly lithium-ion batteries that appeared in the 1990s, due to their high energy density, The advantages of long cycle life and high working voltage make it one of the most eye-catching power sources. However, with the deepening of people's understanding of battery usage conditions, it is found that in many cases the battery is used under the condition of higher than normal temperature, and the working or storage under high temperature conditions has more stringent requirements on the working stability and storage stability of the battery system. ,...

AI Technical Summary

Problems solved by technology

However, with the deepening of people's understanding of battery usage conditions, it is found that in many cases the battery is used under the condition of higher than normal temperature, and the working or storage under high temperature conditions has more stringent requirements on the working stability and storage stability of the battery system. , so that the industry has paid attention to improving the electrical performance and high-temperature storage performance of batteries under high-temperature conditions; under high-temperature environments, a series of changes will occur in the lithium-ion battery system, and the positive electrode material will be oxidized together with the electrolyte due to its high activity. reaction, which affects the performance of lithium-ion batteries. When the negative electrode material is formed in lithium-ion batteries, a passivation film will be formed on the surface. When it is in a high temperature environment, the passivation film will be dissolved and destroyed, thus affecting the cycle performance and capacity of the battery. At the same time, when the battery is stored in a high temperature environment for a long time, the electrolyte will volatilize or reductively decompose, causing the battery to "flatulence", which may cause safety problems such as battery explosion; The design of the liquid must take into account the compatibility between the positive and negative materials of the lithium-ion battery and the electrolyte in a high temperature environment, reduce the probability of the reaction between the electrolyte and the positive and negative materials, and improve the stability of the passivation film

[0003] At present, non-aqueous electrolyte batteries have been put into practical use, but their durability is still unsatisfactory, especially at a high temperature of 45°C, the service life is short, and non-aqueous electrolyte lithium-ion batteries are required to work normally in cold regions. It is also necessary to take into account the high and low temperature performance. In the non-aqueous electrolyte lithium-ion battery, the non-aqueous electrolyte is the key factor affecting the high and low temperature performance of the battery. In particular, the additives in the non-aqueous electrolyte are particularly important for the high and low temperature performance of the battery.

In order to improve the performance of the battery, many researchers have added different additives to the electrolyte to improve the quality of the passivation film, thereby improving the performance of the battery. Although these additives can improve the high and low temperature discharge performance of the battery, the effect is not Not ideal, the battery cannot be practical

Images