As automakers add stop-start to their vehicles, the lowly 12-volt battery is getting a makeover.
Stop-start systems can wear out conventional lead-acid batteries because the engine restarts every time a vehicle with stop-start pulls away after stopping.
Likewise, other newly electrified accessories such as power steering, water pumps, oil pumps and parking brakes are increasing the workload of the 12-volt battery.
So suppliers have designed batteries that can withstand frequent discharges and recharges. At least two types have emerged as upgrades:
• The absorbent glass mat battery is an improved lead-acid battery that is more durable -- and more costly -- than a conventional battery. Johnson Controls Inc. of Milwaukee is a leading supplier.
• A 12-volt lithium ion battery offers more durability and better performance than a glass mat battery, but at a much higher cost. A123 Systems Inc. of Waltham, Mass., aims this product at premium brands.