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StoreDot receives patent for introducing a mobile layer of ionic liquid into electrolytes of lithium-ion batteries

Patent for introducing a mobile layer of ionic liquid into electrolytes of lithium-ion batteries granted to StoreDot

With continued success in the portable electronic device market, Li-ion batteries (LIBs) are of increasing interest for applications in electric and hybrid vehicles, surgical tools, and oil and gas drilling, etc., due to their superior energy density and long cycle life.

However, current LIBs employ conventional liquid electrolytes based on organic solvents, which poses a safety concern, especially at elevated temperatures. Specifically, possible side reactions become more dominating at higher temperatures as the rate of chemical reaction between the dissolved lithium salt and electrolyte solvent increases.

The present invention relates to the field of lithium-ion batteries, and more particularly, to electrolytes for preventing lithium metallization.

This disclosure covers electrolytes, anodes, lithium-ion cells and methods for preventing lithium metallization in lithium-ion batteries to enhance their safety.

Electrolytes comprise up to 20% ionic liquid additives that form a mobile solid electrolyte interface during charging of the cell and prevent lithium metallization and electrolyte decomposition on the anode while maintaining the lithium-ion mobility at a level that enables fast charging of the batteries. Anodes are typically metalloid-based, for example include silicon, germanium, tin, and/or aluminum. A surface layer on the anode bonds at least some of the ionic liquid additive to form an immobilized layer that provides further protection at the interface between the anode and the electrolyte, prevents metallization of lithium on the former, and decomposition of the latter.

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