I know we've been through this before, but,! I have a six volt battery that had been left on vehicle for about eighteen months. I got it home and it charged up to full voltage. Now the charger is charging for a few seconds then cutting off, then cutting back in. It is a three cell battery and currently will hold about 5.2 volts. Any suggestion how I can discharge the thing and try again? Twelve volt wouldn't be a problem, but can the stuff be used on six volt? There are now decent six volt solar chargers available at resonable prices. I use twelve volt ones on mine and they have kept the batteries trickled up nicley.