Polymerizable additives for making non-aqueous rechargeable lithium batteries safe after overcharge

摘要

After undergoing overcharge abuse, non-aqueous rechargeable lithium batteries can be left in a relatively hazardous state of charge, representing a safety concern with respect to subsequent thermal or mechanical abuse. Electrolyte additives which electrochemically form conductive polymers can be used to create a short circuit inside the battery as a result of overcharge abuse and automatically discharge the battery internally. The invention is particularly suitable for batteries equipped with electrical disconnect devices which cannot be discharged externally after the disconnect has activated. Aromatic compounds such as biphenyl are particularly suitable additives.