Here is an "interesting" site:

http://www.shaka.com/~kalepa/desulfparts2.htm

I really don't know what voltage you would need to put 90A into a battery for .1 mSec (100 uSec). Maybe 100V? I have no idea. The above link suggest that the voltage goes down as the sulphate is removed.

Making the 100V is not so hard with a charge pump. But it is hard to believe they can actually do this for 20.00 resale. But I have no first hand knowledge of the 90A or the 20.00. I am just going by what you guys are saying. It appears they are "shocking" the plates to set up some vibration and break the crystals off.

They show a picture on this page:

http://www.shaka.com/~kalepa/desulf.htm

I can tell you the thing in the first photo can definitely be made to sell for 20.00 ! The parts are worth about 1.25 total (not including the case). You might be surprised which is the most expensive part on that board...

This page is actually pretty interesting:

http://www.shaka.com/~kalepa/lowpower.htm

There are some tables at the bottom that show maximum pulse currents of 5 Amps into a 12V battery.

Mike

__________________
1998 C230 330,000 miles (currently dead of second failed EIS, yours will fail too, turning you into the dealer's personal human cash machine)
1988 F150 144,000 miles (leaks all the colors of the rainbow)
Previous stars: 1981 Brava 210,000 miles, 1978 128 150,000 miles, 1977 B200 Van 175,000 miles, 1972 Vega (great, if rusty, car), 1972 Celica, 1986.5 Supra