Patent ID: 9537329
Date: 2017-01-03
CPC Classifications: H02J

Claim:
1. A battery management circuit, comprising: a plurality of cell connections whereby a corresponding plurality of battery sections are connectable in series between a load output and ground such that the positive terminal of each battery section in the series is connected to the negative terminal of the subsequent battery section in the series, except that the negative terminal of the first battery section in the series is connected to ground and that the positive terminal of the last battery section is connected to the load output; balancing circuitry connected across a plurality N of the cell connections whereby, when a corresponding plurality of battery sections are connected thereto to drive a load connected at the load output and when activated, the balancing circuitry is configured to provide a supplemental current across the connections of one or more weaker ones of the battery sections from one or more stronger ones of the battery sections; a controller circuit connected to the cell connections to monitor the charge level of batteries connected thereto and connected to the balancing circuitry to activate the balancing circuitry in response to detecting one or more of the battery sections being discharged below a first level; and charging circuitry connected to the controller circuit, coupled to the cell connections, and having an AC input, wherein in response to the controller circuit detecting the voltage across the plurality of cell connections being at or below a second level of discharge, the controller circuitry activates the charging circuitry, where the second level of discharge is a minimum allowable terminal voltage of the batteries.