Artifact, 4 (4)
Uncommon (U1)
{2}, {T}: Put a charge counter on Green Mana Battery.
{T}, Remove any number of charge counters from Green Mana Battery: Add {G} to your mana pool, then add an additional {G} to your mana pool for each charge counter removed this way.
Illus. Christopher Rush

10/4/2004: Can be tapped even if it has no counters.
Legal in Vintage (Type 1)
Legal in Legacy (Type 1.5)
Legal in Commander