Battery life

How long do you think the battery on a Mercedes C-Class should last? I've just had to have a second new one fitted (3 months outside warranty) Each one has lasted 18 months roughly. Mercedes refused any liability although the dealer gave me 10% off battery price. In 50 years motoring I've never known anything like this. What are your thoughts and recommended action?
You don't say how far your are regularly driving the car. If most of your runs are fairly short then the batteries won't last long because in order to achieve better fuel economy and lower CO2, the alternator puts minimum load on the engine and batteries therefore take longer to recharge.
Answered by Honest John on

Ask Honest John