XS Power

XS Power was founded in the early 2000s and built its reputation in the competitive car audio market, where sustained current delivery — not just peak cold-cranking amps — determines whether an amplifier system survives extended playback. The brand's flagship D-series batteries use absorbed glass mat (AGM) construction with M6 bolt-style terminals in place of standard SAE posts, a design choice that reduces connection resistance in high-current installations but requires M6 terminal adapters for vehicles with conventional battery cables.

The D3400 (Group 34) is the most widely sold XS Power battery in the consumer channel — it functions as both a car audio reservoir battery and a starter battery in Group 34 vehicles. XS Power also produces LiFePO4 (lithium) batteries, supercapacitor banks, and alternators for performance applications. The brand markets primarily through authorized dealers and specialty retailers; warranty coverage through unauthorized Amazon sellers is limited to the seller's return window per XS Power's brand policy.