HIGH VOLTAGE BATTERY FORMATION PROTOCOLS AND CONTROL OF CHARGING AND DISCHARGING FOR DESIRABLE LONG TERM CYCLING PERFORMANCE

摘要

Improved cycling of high voltage lithium ion batteries is accomplished through the use of a formation step that seems to form a more stable structure for subsequent cycling and through the improved management of the charge-discharge cycling. In particular, the formation charge for the battery can be performed at a lower voltage prior to full activation of the battery through a charge to the specified operational voltage of the battery. With respect to management of the charging and discharging of the battery, it has been discovered that for the lithium rich high voltage compositions of interest that a deeper discharge can preserve the cycling capacity at a greater number of cycles. Battery management can be designed to exploit the improved cycling capacity obtained with deeper discharges of the battery.