US Patent 11207946 Heating system of vehicle

An indoor heating line is arranged to pass through a heater core for a coolant heater and indoor air conditioning, and is provided with a first pump so that coolant can flow. A battery heating line is branched from a downstream point of the heater core and connected to an upstream point of the coolant heater after passing through a battery heat exchange part for temperature-raising a high voltage battery, where the battery heating line includes a first heat exchange flow passage that connects a downstream point of the heater core to a first side of the battery heat exchange part, and a second heat exchange flow passage that connects a second side thereof and an upstream point of the coolant heater, where the first heat exchange flow passage and the second heat exchange flow passage are configured to mutually exchange heat.