Not universal

Lithium battery chargers and lead-acid battery chargers are not universal.

Lithium batteries and lead-acid batteries are different types of batteries, and their charging principles differ. Lithium batteries are charged using constant voltage, while lead-acid batteries are charged using constant current. Lithium battery chargers use a constant current-constant voltage (CC-CV) charging mode, while lead-acid battery chargers mostly use a constant voltage or staged constant current charging method. Furthermore, the voltage levels of lithium batteries and lead-acid batteries are not compatible. Using a lead-acid battery charger to charge a lithium battery can cause bulging, deformation, and even explosion. Using a lithium battery charger to charge a lead-acid battery makes it difficult to fully charge the lead-acid battery. Over time, the lead-acid battery will easily become depleted, ultimately shortening its lifespan.