NOCO Genius Battery Charger 5 Amp. Charges / maintains lead acid and lithium-ion batteries. Start voltage sensor detects dead batteries as low as 1 volt. Force mode allows manual charging of extremely dead batteries (down to 0 volts). Built-in battery desulfation mode to recover worn-out batteries (Genius 5 / Genius 10). Smart indicators quickly detect when the battery charger is connected in reverse polarity, connected to an incompatible battery, or if the battery is failing. Detachable clamps for permanent charging cable installation.