Abstract: A rechargeable lithium-ion battery system includes a cell pack comprising a plurality of battery cells, a charger connection configured to connect to an external battery charger to supply a first charge current to recharge the plurality of battery cells, and a safety switch positioned between the cell pack and the charger connection and operable to divert the first charge current from the external battery charger through a cell recovery charger to the cell pack. The system is configured to operate the cell recovery charger to deliver a charge current to the cell pack to charge the plurality of battery cells until a cell voltage of each of the plurality of battery cells is greater than a threshold cell voltage or until a time out period is reached.

Abstract: A rechargeable lithium-ion battery system includes a cell pack comprising a plurality of battery cells, a charger connection configured to connect to a battery charger to supply a charge current to recharge the plurality of battery cells, and a safety switch positioned between the cell pack and the charger connection and operable to divert charge current from the battery charger through a cell recovery charger to the cell pack. The cell recovery charger is configured to deliver a reduced charge current to the cell pack that is less than the charge current supplied by the charger.