My Skoda dealer insists on doing a drop load test every service presumably with one of those big shorting link things. As an electronics engineer I shudder at the thought on short circuiting a lead acid battery and the damage it does to the plates.

Theres no need to test a one year old battery that has never given any trouble. Or are they trying invest in their future by insuring they damage the battery early so they can sell me another in 2 or 3 years time?

The "drop test" doesn't short the battery - it allows a high current to flow, approximating starter current, for a very short time, typically 10 seconds and evaluates the voltage drop during that time.

If that concerns you, I wouldn't go starting your engine!

My battery is over 4 years old and I know that it could fail at any time. I don't want this to happen at an inconvenient time. Is it possible to test a battery to predict when it will fail? I know you can test it once it has failed, but can testers predict it before it happens?

Battery on our Micra is over 7 years old and is the original. Car gets used everyday and still starts the car fine, will worry when it doesn't.

But on the Caterham I find that a good quality batteries lasts about 5 years on average. Its only used during the summer mainly at weekends but during the winter the battery is stored indoors and is charged with a conditioner type charger frequenty to try and prevent the calcium? build up in the bottom that tends to stop them working. Current battery (Exide Premium 063) is 6 years old next month and was working fine when last used in October. Was garanteed for 4 years and a new one is currently £44.34 at Euro Car Parts. Not going to get stressed at that price.

I would call Vauxhall main dealer,they often have good deals on batteries.