Method for heating a high voltage vehicle battery

摘要

An exemplary system and method for use in cold environments in order to heat a high voltage vehicle battery, such as the type commonly found in hybrid vehicles. Some high voltage vehicle batteries—like those based on lithium-ion chemistries—perform better when their battery temperature is in a certain temperature range. In an exemplary embodiment, a battery heating system includes a switch, a battery heater and a high voltage vehicle battery, and initially uses electrical power from an external power source to heat the battery and then uses electrical power from an internal power source to heat the battery. The switch determines which power source is used to heat the battery, and may be dictated by whether the battery heating system is plugged into the external power source and/or a vehicle propulsion system is active, to cite several possibilities.

主权项

1. A battery heating system for use with a vehicle, comprising:
a switch having first and second inputs and an output, the first switch input receives electrical power from an external power source located outside of the vehicle and the second switch input receives electrical power from a separate internal power source located inside of the vehicle; a battery heater having an input, the battery heater input is coupled to the switch output and receives electrical power from the switch output; a high voltage vehicle battery being at least partially used for vehicle propulsion and being different than the separate internal power source, the battery heater is thermally coupled to the high voltage vehicle battery; and a control module being coupled to the switch and being configured to monitor one or more conditions around the vehicle and to control a state of the switch at least partially in accordance with the monitored conditions, wherein the control module is configured to control the state of the switch so that the switch provides the battery heater with electrical power from the external power source when the switch is in a first switch state and the vehicle is plugged into the external power source, so that the switch provides the battery heater with electrical power from the separate internal power source when the switch is in a second switch state and the vehicle is unplugged from the external power source, and so that the switch continues to provide the battery heater with electrical power from the separate internal power source when the vehicle is being driven and while a temperature of the high voltage vehicle battery is below a target temperature.