Patent ID: 8189305
Filing Date: 2012-05-29
Classification: B60R

Abstract:
1. An auxiliary power system for an electrical load in a vehicle electrical system having a primary electrical bus and an electrical load, the auxiliary power system comprising: an electrical input adapted to be connected to the primary electrical bus for receiving power from the primary electrical bus; an electrical output adapted to be coupled in electrical communication with the electrical load of the vehicle electrical system; an auxiliary battery having first and second terminals for producing a battery voltage that provides auxiliary power to the electrical load through the electrical output; a thermal transducer in physical contact with the auxiliary battery, the thermal transducer generating an electrical signal representative of the temperature of the auxiliary battery; a charger circuit electrically connected to the first and second terminals of the auxiliary battery and responsive to the thermal transducer, the charger circuit adapted to receive power from the primary electrical bus through the electrical input, the charger circuit adapted to deliver a controlled charging current to the auxiliary battery via the first and second terminals, and wherein the charger circuit is responsive to at least the temperature of the auxiliary battery to control the charging current delivered to the auxiliary battery; and an output power delivery circuit comprising first and second unidirectional electrically conductive devices and a controllably conductive device, the first unidirectional electrically conductive device electrically coupled between the electrical input and the electrical output so as to provide power to the electrical load from the electrical input during a normal power condition, the second unidirectional electrically conductive device electrically coupled in series with the controllably conductive device; wherein the series combination of the second unidirectional electrically conductive device and the controllably conductive device is electrically coupled between the electrical output and at least one of the first and second terminals of the auxiliary battery to provide a path for power delivery from the auxiliary battery to the electrical load during an emergency power condition.