Note: This project has been superseded by Da Pimp which can desulphate, test and charge batteries of different voltages.
Mini-D is a desulfator designed to be used with 12V lead-acid
batteries. This device can restore new life to batteries which have
been sitting without a charge for extended periods of time.
Desulfation removes sulfur crystals that have formed around the
lead plates. On a 12V battery sulfur crystals begin to form when a
battery is stored at a voltage of less than 12.3V. These crystals
are undesirable as they cause resistance within the battery which
eventually leads to a battery unable to pass current. Mini-D breaks
the crystals by emitting a high frequency / high voltage / low power
pulse which creates a resonance inside the battery.
I have desulfated and sold dozens of lead-acid batteries. A batteries
improvement can be measured by applying a load to the battery
periodically and watching the voltage drop. A 60lb battery will
take roughly three weeks to desulfate.