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[Diamond Black Geezer]

Ok, just bought my first ever brand new car battery. I know, amazing stuff. So my question is - any tips on charging it up for the fist time? Obviously got a battery charger, just wondering if there's any old-boys tips I should know about? You know, 'always charge it for 24 hours solid for the first time', or 'don't over charge it for the first time' etc...

PS Don't but the GM 65 a/h battery from Vx.... buy the 70 a/h - it's about a tenner cheaper!!! 

[aaronjb]

It should have arrived (mostly) charged.. fit it, forget it

[Diamond Black Geezer]

Ahhhh fair enough... in which case if it's not got decent charge in it, that's a sign it's been sitting for a while, then? Might try that, and if not, then I'll be taking it back and asking for a better one.

Swear the indicator was black, so therefore empty... 

[aaronjb]

Yeah, if it's flat as a pancake (or, I'd say below ~12.2V or so) then it wants taking back as it's probably discharged enough that it'll never be quite right..

If it's borderline though, a trickle charger or maintenance charger (like an Optimate) for a while should bring it back to life.

I find the indicators ridiculously hard to read, mind..

[Diamond Black Geezer]

Cheers, so my old man's always looked at car batteries and said along the lines of "look, that's got 11.5volts in it, well, it's a 12volt battery, so that's not bad, that's 9 out of ten. so pretty good." to which my point has always been "Well I can wire up several AA batteries together to make 12volts, doesn't mean I can start a car on it!" 

So will check it tonight. I've been faithfully assured by a decent bloke who has worked there donkeys years I trust, that they haven't been sitting long. That said he wasn't there when I picked up the battery, so I may well have got a dusty one from the back, that they want to get rid of first. I suppose it's like buying milk. Hmmm, at my girlfriend's tonight, so will have to have a look Tuesday night. I'm not having a duffer!

[Kevin Wood]

Although nominally termed 12 Volt batteries, a car battery is dead flat if it only reads 12 Volts, never mind lower than that. They should be 12.6-12.8 V fully charged.

I would say, if it doesn't have enough charge in it to start the car, take it back. Batteries should be regularly charged in storage, and if it's been allowed to go flat, it may well have been damaged irreparably.

Although there might be some mileage in fully charging a battery before fitting, if it has been looked after in storage, the benefits would be negligible, and car charging systems are good enough these days to bring it back to full capacity without overcharging quite quickly.

[Diamond Black Geezer]

Cheers  Muchh appreciated.

Seems such a stupid question... but this shows it's not perhaps as stupid as I first thought... though worth bearing in mind for anyone getting a 65 a/h from Vx that get the 70 a/h as they are cheaper.... though I think we know why now 

[Kevin Wood]

There's more to a battery than the Ah capacity, though.

Consider that, to start a V6, the starter motor probably draws 200-250A for maybe 3 seconds. That's about 0.2 Ah by my reckoning. Much more important is the cold cranking current it can deliver and the general build quality that influences its' life.

[Diamond Black Geezer]

There's more to a battery than the Ah capacity, though.

Consider that, to start a V6, the starter motor probably draws 200-250A for maybe 3 seconds. That's about 0.2 Ah by my reckoning. Much more important is the cold cranking current it can deliver and the general build quality that influences its' life.

I'll second that Mr Wood, yes. To be honest I'm happy to have got a genuine Vx battery for a tenner less than I expected and bringing it to basically the same price as 'other brand' batteries... soon as I find out what voltage anyway, if it's giving out otherwise head will roll at the Stealer!!

[Webby the Bear]

To highlight exactly what Kev's just said.....

I was parked up waiting for SWMBO a week back when the first real cold night came. Had the radio on and nowt else for about ten mins. SWMBO got in. i turned key. Click. 

Got the RAC out who put it on the charger. Started immediately. Took it for a 20 minute run. All (touch wood) is now well and no more problems. Batteries dont like the cold!!

[Diamond Black Geezer]

That fair enough, I've reread what's been said  My only point was, if the battery is dead from new, (which I don't know yet if it is for sure, yet, I may have just not seen the green indicator) I'd rather go and swap it for one that is fully charged, as that just 'feels' the better bet.

[dbug]

Don't take much notice of the green/black indicator.  Put a meter across the terminals before fitting - as said should read 12.6 - 12.8 volts - at the moment you just keep saying it may be "faulty" - test it

[Vamps]

As others have said, brand new battery, if it does not start your car without you charging it take it back.............

I had to do this on my 4 pot when I had it, brand new battery fitted, would not crank and high speed, had the parts van bring me out another which still did now work..........

Turned out I needed an new starter motor................

[Diamond Black Geezer]

Don't take much notice of the green/black indicator.  Put a meter across the terminals before fitting - as said should read 12.6 - 12.8 volts - at the moment you just keep saying it may be "faulty" - test it

Appreciate the point, but given I was 4 miles from home and at work at the time of posting, and then at my girlfriend's last night, I hope you'll forgive me for choosing a night of homemade food, dancing to old LPs on a restored '60s record player, real ale and....some other stuff... to nipping home to check the voltage of a battery   

However, all shall be glad to hear I texted home and asked if someone could get a reading for me, and it's at 13v... so all good!

It's just any other electrical device I've had since new they've all needed a 'special' charging routine, like many things. I mean who would think about pumping up and down shock absorbers to 'prime' them a few times before fitting? Hopefully my question isn't as daft as I first thought    Mods may close the thread, if wished. Thanks to all 

[Kevin Wood]

Appreciate the point, but given I was 4 miles from home and at work at the time of posting, and then at my girlfriend's last night, I hope you'll forgive me for choosing a night of homemade food, dancing to old LPs on a restored '60s record player, real ale and....some other stuff... to nipping home to check the voltage of a battery   

That's the problem with some people.. no dedication to the cause. 

Still.. could have been worse. At least you weren't drinking Peroni and listening to CDs.