Actually, yes, but not without help. Reversing the polarity on a battery can happen only a couple of ways. For all intents and purposes, the battery will be ruined. You could technically charge it up, negatively, and continue to use it, but your plates are designed with the positive plates being lead dioxide, and the negative being composed of a sponge lead, which would now be reversed. The fact of the matter is, a lead acid battery cannot reverse its own polarity without an external stimulus. It is just not possible. read more...