Light Duty Hybrid/Electric Vehicle Flashcards

What battery chemistry is most commonly used in modern light-duty plug-in electric vehicles?

Answer: Lithium-ion

Lithium-ion batteries offer high energy density and are standard in current EVs and most plug-in hybrids.

What is the function of regenerative braking in a hybrid/electric vehicle?

Answer: It converts kinetic energy into electricity to recharge the battery

Regenerative braking uses the motor as a generator to recover energy that would otherwise be lost as heat.

A customer reports reduced fuel economy and frequent engine starts in their hybrid. Which is a likely cause?

Answer: A degraded high-voltage battery with reduced capacity

As the HV battery loses capacity, the engine runs more often to maintain charge, lowering efficiency.

What is the role of the inverter in an electric drive system?

Answer: It converts DC from the battery to AC for the traction motor

The inverter changes high-voltage DC battery power into three-phase AC needed to run the traction motor.

What is the purpose of the DC-DC converter on a hybrid/electric vehicle?

Answer: It steps down high voltage to charge the 12V system

The DC-DC converter replaces the alternator by stepping high voltage down to power the 12V accessories and battery.

Which cooling method is commonly used for high-voltage battery packs to maintain optimal temperature?

Answer: Liquid or active air thermal management

Battery packs use liquid or forced-air thermal management to keep cells within their safe operating temperature range.

What should a technician do with a high-voltage battery pack that shows signs of thermal runaway or swelling?

Answer: Isolate it, follow OEM emergency procedures, and avoid direct contact

A compromised lithium battery is a fire and chemical hazard, so it must be isolated and handled per manufacturer safety protocols.