PORTER-CABLE PCC580B 18-Volt Battery Status Indicator Fully automatic status of charge indication for 18V Lithium-Ion or NiCd batteries Illuminated LEDs show charge status - 1st LED on -low charge, 1st and amp; 2nd LED on - partial charge, all 3 LEDs on - 75-Percent + charged. If no LEDs are visible the battery has a very low state of charge or no charge Automatic shut off after 15 seconds reduces battery drain Remove battery after use