BUCK PRE-CHARGER FOR SERIES-CONNECTED BATTERY MODULES

摘要

Systems and methods of pre-charging battery cells that can reliably pre-charge battery cells included in a plurality of series-connected battery modules. The systems and methods can monitor a value of a pre-charge current provided to the plurality of series-connected battery modules, as well as monitor a voltage level of the battery cells within each battery module. The systems and methods can further switchingly interrupt the pre-charge current within each battery module once it has reached a predetermined threshold current value or the battery cells within the battery module have been charged to a UVP level, causing a flyback current to flow into the battery cells of each battery module that have not yet been charged to the UVP level. Once the battery cells within each battery module have been charged to the UVP level, the systems and methods can provide a full-charge current to the plurality of series-connected battery modules.

主权项

1. A method of pre-charging a plurality of series-connected battery modules, each battery module having one or more rechargeable battery cells, the method comprising:
connecting a charging voltage source across the plurality of series-connected battery modules to cause a pre-charge current to flow into the battery cells of the respective battery modules, each battery module having a buck pre-charging circuit including an inductor; once the pre-charge current has ramped up to a first threshold current value, interrupting the pre-charge current to cause a flyback current to flow from the inductor into the battery cells of each battery module; once the flyback current within at least one of the battery modules has ramped down to a second threshold current value, allowing the pre-charge current to flow into the battery cells of the respective battery modules; alternating between (1) allowing the pre-charge current to flow into the battery cells of the respective battery modules, and (2) interrupting the pre-charge current to cause a flyback current to flow from the inductor into the battery cells of each battery module that have not been charged to a minimum voltage level needed for operation, until the battery cells of all of the battery modules have been charged to at least the minimum voltage level needed for operation; and once the battery cells of all of the battery modules have been charged to at least the minimum voltage level needed for operation, causing, by the charging voltage source connected across the plurality of series-connected battery modules, a full-charge current to flow into the battery cells of the respective battery modules.