Volt Absorb is an ability generally found in Electric type animals. It is usually classified as a hidden or dreamworld ability.
In Battle Use
Animals with the Volt Absorb ability will get a quarter of their health healed when hit by any Electric type moves from their opponents (including non-damaging moves).
This ability likely evolved as a way to protect animals that constantly were attacked by Electric type moves. It is also believed to recharge Electric type animals.