Here's a thread on DIY replacement of the battery.
www.smartcarofamerica.com
Len
DIY - replacing 12v battery (451)
Yesterday I replaced my original battery with a new OE one from Mercedes. The new battery is identical to the original battery in specs. Cost was $176. I couldn’t tell the manufacturer, but in the past, Varta made most Mercedes batteries. This new battery was identical in size to the...
Len