Organic Additives as Redox Shuttles for Overcharge Protection of Lithium Ion Batteries

78950S Lithium-ion batteries have been selected as the long-term battery solution for electric vehicles (EV) and hybrid electric vehicles (HEV). However, lithium-ion batteries are sensitive to certain types of abuse, particularly overcharge abuse wherein the normal operating voltage is exceeded during recharge. In the overcharge state, lithium-ion batteries could cause irreversible, exothermic degradation, leading to the risk of thermal runaway and explosion. The application of redox shuttle additives in the electrolyte has been recognized as one of the most attractive approaches to preventing overcharge abuse. The redox shuttle additive approach employs an electrolyte additive which acts as an internal current shunt when the charging potential exceeds the oxidation potential of the additive. This project will develop redox shuttle additives that meet the requirements for the high-voltage lithium-ion batteries for EV/HEV applications. In Phase I, a series of organic compounds will be explored as redox shuttle additives in commercial electrolyte solution for lithium-ion batteries. Commercial Applications and Other Benefits as described by the awardee: The successful completion of redox shuttle species with sufficiently positive oxidation potential (at least above 4.2 V versus Li/Li+) should provide excellent overcharge protection for lithium-ion batteries, significantly impacting EV/HEV applications and other many consumer applications.