Electric Vehicle Battery Temperature Control

Electric Vehicle Battery Cooling 

The request for Electric Vehicle (EV) battery cooling is sent from the Battery Energy Control Module (BECM) to the HVAC control module through the High Speed (HS) Controller Area Network (CAN) power mode zero systems bus. The BECM can request EV battery cooling when the vehicle is driven or connected to an external power supply to charge the EV battery.

The HVAC operates the Air Conditioning (A/C) system to cool the EV battery coolant using the EV battery cooler. The HVAC operates the following:

• Electric A/C compressor.
• EV battery cooler isolation valve.
• A/C isolation valve (quantity 5). The HVAC energizes the A/C isolation valves necessary for the refrigerant to flow to the EV battery cooler.
• The front A/C isolation valve is energized only if no cooling is required for the passenger compartment.

For additional information, refer to: AIR CONDITIONING .

For additional information, Refer to: ELECTRIC VEHICLE BATTERY TEMPERATURE CONTROL .

Electric Vehicle Battery Heating 

Electric Vehicle (EV) battery heating only operates when connected to an external power supply to charge the EV battery. The Battery Energy Control Module (BECM) controls the EV battery temperature control system and communicates heating requests to the HVAC control module when required. The BECM and HVAC communicate through the High Speed (HS) Controller Area Network (CAN) power mode zero systems bus.

For additional information, Refer to: ONBOARD CHARGING MODULE .

The BECM controls the following for the EV battery coolant and heat to flow to the EV battery from the climate control heat exchanger:

• EV battery coolant pump
• EV battery changeover valve.

For additional information, Refer to: ELECTRIC VEHICLE BATTERY TEMPERATURE CONTROL .

The HVAC uses the High Voltage (HV) interior heater to heat the climate control coolant. The power for the HV interior heater is provided by the external power supply. To circulate and heat the climate control coolant to the climate control heat exchanger, the HVAC operates the following:

• HV interior heater through a Local Interconnect Network (LIN).
• Climate control coolant pump with a Pulse Width Modulation (PWM) signal.
• Climate control changeover valve.

The HVAC controls the rate of flow of the climate control coolant with a PWM signal to the climate control coolant pump. The HVAC operates the climate control changeover valve to direct the climate control coolant to the climate control heat exchanger.

Electric Vehicle Battery Heating Coolant Flow Schematic 

Courtesy of JAGUAR LAND ROVER NORTH AMERICA, LLC

A = CLIMATE CONTROL COOLANT SYSTEM: B = ELECTRIC VEHICLE (EV) BATTERY TEMPERATURE CONTROL SYSTEM: C = CLIMATE CONTROL COOLANT FLOW - HOT: D = CLIMATE CONTROL COOLANT FLOW - COLD: E = EV 

BATTERY COOLANT FLOW - HOT: F = EV BATTERY COOLANT FLOW - COLD: G = COOLANT CONNECTION - NO FLOW  .