I got Nimh batteries for $20 dollars, got a charger for $5 or so... just drain the batteries all the way before charging them. Leave them in the charger overnight and voila...
2000 Audi A8 SWB Silver/Black
1992 BMW 525iT/5 White/Blue [MPars, HIDs, cargo net]
1989 525i [scrapped]
1995 BMW 318i DASC [sold]