A battery protection device for preventing vehicle batteries from being
drained to the point that the battery cannot start the vehicle includes
an electrical meter that measures at least one electrical characteristic
of the battery and a microprocessor. The microprocessor compares this
measurement to a minimum starter value corresponding to a battery charge
level below which the battery will not be able to start the vehicle. If
the minimum starter value is equal to or greater than the current
measurement from electrical property measuring device, the battery
protection device will open a switch, disconnecting the battery. An
indicator then notifies the vehicle operator that the device has been
actuated and upon his return to the vehicle, the operator will be able to
reset the device and start the vehicle or turn off the electrical device
that was left on.