When is a car battery knackered

My missus only uses her car for short journeys, often just a few miles (yeah I know, but kids in tow etc) so inevitably over the cold snap the battery has gone flat. First time I started it with jump leads, yesterday I put it on the charger overnight (just about to unplug it now).

Is this likely to be the start of the end for it? The cars about 5 years old and I assume original battery. How do you tell when the battery is at the end of its life (other than car not starting).

Oh and I probably ought to check the electrolyte levels, but its a new beetle, and you have to dismantle half the engine bay to get the battery cover off grrrr.

Battery is more than likely a sealed item.

If it won’t hold charge then it is probably on the way out, especially if overnight charging doesn’t remedy it.
Might be worth getting the alternator checked out too, could be that the alternator isn’t charging it correctly.

I think halfords do free battery checks to tell you if it’s had it or not.

The battery must be able to provide a certain voltage while cranking the engine – no way to test this without a discharge tester but Kwik fit type places will usually test it for free if they think they might be able to sell you a new one.

Having been fixing this for the last week myself go out and give it a really long drive – 2 hour stint or something – fixed mine up a treat.

Battery is dead when the battery is dead, if that makes sense. If it doesnt turn the car over enough to get it to fire up, or if you cant leave it with its side-lights on for as long as you need to, it’s dead. Until then its dying. Batteries are dying from their first day, just like us 🙂

Usually with an older battery, one run-flat instance is enough to trigger more rapid decay, just keep an eye on it and make sure you change it when struggles to start in the morning. Remember that cold temps upset batteries as the chemical reaction inside doesnt work as effectively, so if it warms up for a bit you’ll have more life yet.

I’ve found this useful if a car isn’t used that often and garaged to keep it all dry. You can fit it and it monitors the battery so won’t fry it.

http://www.accumate.co.uk/it010001.htm