Microcapsule and preparation method thereof, electrolyte and preparation method thereof and battery

Abstract

The invention provides a microcapsule and a preparation method thereof, an electrolyte and a preparation method thereof and a battery, and belongs to the technical field of batteries. The microcapsule comprises a capsule wall and a capsule core. The capsule wall is made of a first material. The capsule core is made of a second material, and the second material comprises silicon resin with flame retardance. The capsule wall covers the capsule core below a target temperature, the capsule wall is broken above the target temperature and releases the capsule core, and the first material is not dissolved in the electrolyte at least below the target temperature. The microcapsule is dispersed in the electrolyte of the battery, so that the electrical property of the battery is basically not influenced. When the temperature of the battery is higher than the target temperature, the capsule wall of the microcapsule is softened and broken, the microcapsule can release the capsule core of the microcapsule, and the silicon resin with flame retardance forms a diffusion shielding layer to prevent vaporized organic matters generated by high-temperature thermal decomposition of an internal high polymer material from diffusing to a combustion area. Meanwhile, the silicon resin has a very good heat insulation effect, heat transfer in the combustion process can be blocked to prevent continuous reaction, and then the high-temperature safety performance of the battery is improved.

Description

technical field [0001] The present application relates to the field of battery technology, in particular, to a microcapsule and a preparation method thereof, an electrolyte and a preparation method thereof, and a battery. Background technique [0002] Due to its high voltage, energy density and good cycle performance, lithium-ion batteries are increasingly used in energy storage systems such as electric vehicles. [0003] The working efficiency of lithium-ion batteries is greatly affected by temperature, and its performance will be in an optimal state only within a suitable temperature range. Lithium-ion batteries will generate a certain amount of heat during charging and discharging, and the temperature of the battery itself will change during charging and discharging, which is mainly manifested as a temperature rise, especially in the case of high current and high power operation. . [0004] Existing lithium-ion batteries add flame-retardant additives and high-temperatur...

AI Technical Summary

Problems solved by technology

[0004] Existing lithium-ion batteries add flame-retardant additives and high-temperature-resistant additives to their electrolytes to prevent lithium-ion batteries from smoking at high temperatures, or even catching fire and exploding. This type of additives in the electrolyte increases the viscosity of the electrolyte and reduces the electrolysis The activity of the liquid, on the other hand, will have a greater negative impact on the formation of the battery SEI film

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