Battery Staying Charged During Prolonged Vehicle Storage

You have a couple options to keep the battery alive!

1. Consider installing an Optima battery. They hold their charge forever, they produce much more cranking power than a lead acid battery, and they do not gas out. This alone is worth the price. That means no more battery terminal corrosion and very little battery box rust. Now be forewarned that these batteries do not fit perfectly in your battery box tray - but they will work. We prefer the Model 34 red top. You will need to purchase a longer ground cable at your local auto parts store to allow the cables to reach the terminals. You may also need to fabricate a plastic cover to protect the exposed terminals from shorting out. Let me tell you, your engine will spin like it never has before!

Optima installed in 116 chassis

Problem & Solution

Common among these chassis:

W108 W109
W110 W111 W112 Sedan
W111 W112 Coupe
Classic Sedans

NOTE: January 2012 - Optima has recently changed their battery line.   The number 35 looks like the best for Mercedes.  A couple others will work. None will fit perfectly. Just make sure the posts negative and positive are on the correct side.

2. Use a very low amp float charger. Plug this into household current and connect to your battery. It will keep your battery charged. Very helpful if you are storing the car in a cold place. Keeping a lead acid battery fully charged at low amps will really help to extend its useful life.

3. Disconnect your battery. That will only help for short periods. Not the best recommendation for aging lead acid batteries as many will still continue to discharge on there own over long periods. 

NOTE: In sub freezing climates we also recommend you use a 120 volt battery heating pad.