Hi,

This morning I thought after a hellish frost it was a good time to check my ginger monsters battery when I did it read 12.3v bear in mind this was after a 3 mile journey last night and about 20 minutes idling to de-ice the car, this morning I went on it must have been a 15-20 mile thrash, the alternator is working well pushing 14.5 on idle, I stopped the engine and left it for about 5 minutes and checked again and the voltage seemed to be holding on well to 12.7v do you reckon the battery is alright but depleted due to a sudden drop in temps and a few short runs?

12.7v in a 12v battery seems ok to me, they just charge at a higher voltage.

Yeh I reckon it's alright to be fair it always starts *touchwood* I doubt it charged aswell as it should on the way home last night with just about everything switched on to clear the way, hahaha I will check it again in a few days.

seems fine to me your battery won't hold 14 volts , it may read 14v with engine running/ charging battery . you are reading float voltage , this is voltage that will drop off quick after engine or a battery charger has just been removed and will settle around 12.4-12.6ish volts after 30mins or so if it drops to 12.2v or below 12v start to worry after been stood a few hours.

hope this helps

Yeh 14.5 with engine running so the alternator is working just fine, checked it this morning and it's 12.4 now I think it just needs a few longish thrashes, it was really cold over night a few times and I decided to drive home the quick way which is nowhere really that's all, cheers for the responses.

Checking the voltage of a standby battery proves pretty much nothing.

Joining 8x AA batteries will provide a similar voltage but won't start a car. The way to determine how healthy a battery is requires checking the voltage while under a large load

I understand this, but the battery voltage gives you a rough idea of the general charge of the battery, I wouldn't have thought a 12 month old battery would be in such a terrible state of discharge anyway really.

Got it load tested today it's a bit low for the battery it's self but it's still kicking out more CCA than an OE battery so with a decent run it seems it will be alright.