Start-stop batteries must have sufficient energy to restart the engine. When the driver presses down on the clutch pedal ready to pull away, or releases the brake pedal in an automatic vehicle, the engine automatically restarts. Having a reliable battery to create and store energy is crucial for start-stop vehicles.
Drivers recoup the additional cost associated with start-stop technology—about $250 to $300—within three years in the form of less money spent on gas. The investment then continues to pay an annual dividend of $100 in gas savings for the rest of the vehicle’s life (assuming gas prices stay constant). That’s an excellent return by any measure. With today’s gas prices, a five percent savings in fuel may amount to around $40 a year, or about 80 cents a week.