This is an excellent article on WHY lead acid batteries go bad; and how to fix the problem.
Of course they don’t mention that the Capacitive Battery Charger does this ‘corrective’ action too, is simple and inexpensive for anyone to home-make AND goes one step further. The CBC can remove sulfation from batteries that have been undercharged for so long that NO ordinary charger can recover them (might take 80 VDC to break through the sulfation layers).
Bedini Technology has another ‘battery related’ spin. They’ve discovered that lead acid batteries are Free Energy Accumulators when connected to a proper apparatus. More on that later.
Modified Capacitive Battery Charger (can run off inverter)
Capacitive discharge welding can weld dis-similar metals together.