Always use a battery charger that is compatible with the type of battery (NiMH, LiPo, Li-Ion, or LiFe) you are using. Never plug a battery into a charger unless you are sure the battery and charger are %100 compatible. Do not use any charger or battery that is visibly damaged in any way.
Consult our battery compatibility charts for recommended batteries.
Here several helpful videos to help understand airsoft batteries.
Battery handling tips