Battery in storage - voltage?

[M-B Dave]

What [retained] voltage should I expect to see from a battery that has been stored for a few months? That is, before fitting it in, measured at room temperature? It's a sealed, maintenance-free type.

 

[panason1c]

I would want to see around 12.5v as a minimum.

 

[television]

As above 12.5 volts as you can keep them a few months and they stay at this level

 

[L John]

Batteries not in use should be charged at least every 3 months and as long as its not under 12V it should be OK.
Batteries going below 12v in storage get sulphated plates. Definitely agree with 12.5V being the minimum, any lower is asking for trouble.

 

[television]

Batteries not in use should be charged at least every 3 months and as long as its not under 12V it should be OK.
Batteries going below 12v in storage get sulphated plates. Definitely agree with 12.5V being the minimum, any lower is asking for trouble.

Thank you John

 

[L John]

Not sure if this is a myth but I was once told that storing a battery on a cold concrete floor damages it.
Since then I've always put insulation under stored batteries.

Fact or fiction?

 

[balge59]

Not sure if this is a myth but I was once told that storing a battery on a cold concrete floor damages it.
Since then I've always put insulation under stored batteries.

Fact or fiction?

I suppose it might help stopping the battery from freezing up?

 

[L John]

I've avoided putting batteries on the floor long before the internet and never thought to look up an explanation.


Here it says it is a myth.

 

[M-B Dave]

Great, thanks guys. I'm reading 12.65V at the moment, so it doesn't look too bad.

I have a 'storage battery' charger (by Customs Accessories), so going to put it on, what's the maximum voltage I should charge up to? As it's not an automatic type*, I'd have to watch the voltage. The battery is Bosch S5 Silver Plus.

* In fact, even though I bought it new about nine years ago (and never used it), it looks like it was made in 1950s LOL

 

[L John]

My smart charger charges to 14.4v but that's to 100% charge.

Car batteries are never at 100% charge during normal use.

 

[L John]

The main thing is not to charge at high current, my charger is an 8 amp model but it's almost always used at 2 amp, which drops further as the battery reaches 80% or so charge.

 

[television]

The charging voltage is proportional to the current flowing and it will only need a light charge every couple of months, so no fast charging needed.

A battery that has just come off charge will show a higher reading than normal, this soon goes away.

 

[M-B Dave]

The main thing is not to charge at high current, my charger is an 8 amp model but it's almost always used at 2 amp, which drops further as the battery reaches 80% or so charge.

Yes, this one is actually only 1A so will be very slow charging, and I shall monitor the battery anyway.

Just searched for it, and can see some guys are selling one as "Vintage Garage Look" item LOL Smart charger it ain't!

 

[L John]

110v. Not UK then, unless you're using a 240v to 120v transformer?

 

[television]

110v. Not UK then, unless you're using a 240v to 120v transformer?

That is a USA plug on that one

 

[M-B Dave]

110v. Not UK then, unless you're using a 240v to 120v transformer?

Yup, got an UP/DOWN 220-110 transformer for all my stuff "from over there" - built like a tank, weighs a ton and ugly, but works perfectly It would easily cause a heart attack to any elf'n'safety official: it comes with a cord, equipped with a plug on each end: one is US and the other one - EU, the 220/110 sockets on the transformer are universal. A brief instruction (not a warning, mind) on the side suggest user plugs the cord into transformer first, before connecting to the mains

 

[M-B Dave]

That is a USA plug on that one

And there's even a US-style 8x gangway extension under my desk, slightly modified, and with UK wall plug, of course - to take care of all the US-plug [universal voltage] PSUs for different little gadgets ...

 

[television]

And there's even a US-style 8x gangway extension under my desk, slightly modified, and with UK wall plug, of course - to take care of all the US-plug [universal voltage] PSUs for different little gadgets ...

I had the same thing when I moved back from Sweden, easier to have Swedish sockets rather than change a few 100 plug tops.

 

[M-B Dave]

Malcolm and John, one last question, if I may - would you say, based on this charging chart, that the battery is in good condition?

As I have no use for it, I've sold it yesterday, and the chap was in such a hurry to collect, I didn't have time to charge it up to 14.4V, as advised.
Now I'm somewhat concerned it might not be up to scratch? It's not like my life depends on these thirty quid, if it's a dud I'd rather bin it.

 

[L John]

It was still moving up the curve so it looks fine to me, a lot of chargers might stop at 13.8V, as I said earlier a car never charges to 100% capacity.