--------------------- Good alkaline battery voltage = 1.6V Bad alkaline battery voltage = 1.2V Dead alkaline battery voltage = 1V --------------------- Good coin battery voltage = 3.2V Bad coin battery voltage = 2.6V Dead coin battery voltage = 2V or less --------------------- Good sulfate oxide button battery voltage = 1.55V Bad sulfate oxide button battery voltage = 1.3V Dead sulfate oxide button battery voltage = 1.2V or less --------------------- Good NiMh / NiCad battery voltage = 1.2V Bad NiMh / NiCad battery voltage = 1V Dead NiMh / NiCad battery voltage = 0.9V --------------------- Good 9 copper coin battery voltage = 4V Bad 9 copper coin battery voltage = 3V Dead 9 copper coin battery voltage = 2.5V or less. --------------------- End