Abstract: A method for controlling an electric heater of a vehicular heating, ventilation, and air conditioning (HVAC) system includes turning on the electric heater; determining whether an ambient air temperature of a vehicle is higher than or equal to a threshold ambient air temperature, and a battery temperature is lower than or equal to a threshold battery temperature; determining whether battery efficiency is lower than or equal to threshold efficiency when the ambient air temperature of the vehicle is higher than or equal to the threshold ambient air temperature, and the battery temperature is lower than or equal to the threshold battery temperature; and turning off the electric heater when the battery efficiency is lower than or equal to the threshold efficiency, wherein the electric heater is configured to receive electric energy from the battery.

Abstract: A refrigerant amount monitoring and charging control system for an electric vehicle and a method thereof include: a controller; a battery management module electrically connected to the controller; a high-speed charging gun connected to the vehicle when the vehicle is charged and configured to generate a high-speed charging signal during performing high-speed charging and to send the high-speed charging signal to the controller; an ambient temperature sensor electrically connected to the controller and configured to obtain an ambient temperature and to send the obtained ambient temperature to the controller; and a chiller including an electronic expansion valve and an evaporator. A situation where a vehicle battery is unable to be cooled by a refrigerant due to an insufficient refrigerant amount may be prevented by controlling charging power based on a monitoring result of a current refrigerant amount.