Patent ID: 6452361
Filing Date: 2002-09-17
Classification: G08B,H02J,Y02T

Abstract:
A battery system for use in a vehicle having an electric motor for starting an engine, an alternator driven by the engine to generate electricity, and accessory electrical loads comprising:a first battery for selectively powering the motor to start the engine, and having a first voltage level and a charge level; a second battery to operate and maintain the accessory electrical loads, and having a second voltage level; a charging switch connecting the first battery to the alternator; a charge maintenance device connecting the first battery to the second battery to maintain the charge level of the first battery to a predefined magnitude in response to a control signal; a controller coupled to both the first battery and the second battery to monitor the first voltage level and the second voltage level, and operating the charging switch and the charge maintenance device in response to the first voltage level and the second voltage level.