Lightweight 12V lithium systems for professional racing teams (LeMans, NHRA, Daytona, etc), and high performance cars. Replace your heavy lead-acid with a lithium starter battery. Voltphreaks makes 12V lithium batteries that replace 12V lead-acid batteries. Voltphreaks batteries are a drop-in replacement, and are compatible with standard car alternators and charging systems, along with standard float chargers, and standard car battery chargers, making them a complete drop-in replacement! Designed and built in the USA.