Multi-plateau battery charging process and system for charging to the second plateau

摘要

A battery charging method and system, the battery charging method comprising: charging at least one battery at a first voltage for a first time duration; charging the batteries at a second voltage for a second time duration; determining state of charge of the batteries at the end of the second time duration; if the batteries are not substantially fully charged at the end of the second time duration, the total charging time is evaluated to determine if the batteries have been charged for a time duration greater than or equal to a third time duration, and if the total charging time has not exceeded or is not equal to the third time duration, charging the batteries at the first voltage for the first time duration and charging the batteries at the second voltage for the second time duration is repeated; if the batteries are substantially fully charged at the end of the second time duration, battery charging is ceased; or if the total charging time has exceeded or is equal to the third time duration at the end of the second time duration, battery charging is ceased. The battery charging system comprises: a current source; a cutoff voltage controller and timer; at least one battery; respective ones of voltage and current regulators, which regulate voltages applied to and current supplied to each of the batteries; current sensing means, which senses current flowing therethrough the batteries; and a system voltage and current regulator, which shunts current from the batteries.