Club 80-90 Forums

Ok how long should you leave a battery on charge ?

can i just leave it on charge for a few days or will it damage the cells ?

leisure not car BTW

Alright T'Onion
IMHO any half decent battery charger will detect a charged battery and act accordingly, ie hold back on charging until a charge is required. So keeps battery at optimum charge. Differences between leisure/normal batterys shouldn't make any difference?
Kefty

as far as i know there's electrickery at work and the longer you have em on the better they get? perhaps dan wood will explain but summat about density/gravity nonsense i think?
DAANNNNNN HELP

Assuming your battery is a proper wet lead-acid thing and not a 'gel' type then leaving it on charge for a few days shouldn't do it any harm.

As Kefty says, most modern chargers will detect the state of the battery and switch to a 'float' charge that will keep the battery topped up, without overcharging it.

If it's a very old pre-historic "transformer+rectifier" charger then it might go a bit too far. Open circuit voltage on these can be a bit on the high side, and with no regulator the voltage will keep going up and up. Even then, the battery will draw less and less current, so I'd guess that over a few days all you'll do is dry it out a bit and it might need a top-up with distilled water. There's not much in the chemistry of these that can go wrong with overcharging. (Unlike Ni-Cd batteries that will get warm and lose capacity with overcharging.)

So, as long as it's well ventilated I'd leave it on and not worry. (Overcharging will cause gassing... Explosive Hydrogen!)

Have you got a plug in timer or something you could stick on the charger to shut it off if you're not going to be around?

Or, if you are going to be around, and have an accurate voltmeter just check the voltage across the battery and shut it off if the voltage rises above say 15 volts.

ta

it will be in the shed of "pooh" anyway so if it does go pop it will be doing me a favour

Just make sure you open the door, and turn the charger off BEFORE you disconnect the leads!

You'd look daft with no eyebrows...

Dan Wood wrote:
You'd look daft with no eyebrows...

Dan are you saying that i don't with eye brows

oh well there's always a first for everything

Dan Wood wrote: Or, if you are going to be around, and have an accurate voltmeter just check the voltage across the battery and shut it off if the voltage rises above say 15 volts.

What's wrong with a good old fashioned hydrometer?

Bowton Lad wrote:What's wrong with a good old fashioned hydrometer?

This is T'Onion we're talking about. He'd only go and use a hydrometer for making beer...

Dan Wood wrote:

Bowton Lad wrote:What's wrong with a good old fashioned hydrometer?

This is T'Onion we're talking about. He'd only go and use a hydrometer for making beer...

things are that bad yet , i'll stick to drinking beer rather than making it

so how long should a flat 110 amp leisure take to charge

Does the charger have an Ammeter?
Start to charge the battery. Read the ammeter.
Divide 110 (Ahr) by the reading on the charger.

Answer is time to charge in hours
Add 25% for luck


T

T'Onion wrote: so how long should a flat 110 amp leisure take to charge

Depends on how much current your charger can kick out I suppose...
Let's assume about 6 Amps....

Assume you'll get 75% stored of what you pump in (lead-acid batteries aren't that efficient you see...)

So you need to push in about 147 Ah which will take just over 24 hours.

What tends to happen though is that current will fall off as charging progresses so it will probably take a bit longer to squeeze the last bit in.

Still plenty of time before pickyring...

its been on for 48 hrs now , its holding the charge ,

the charger i have has four leds on it , so when the four lights are on its charged , only got two on at the mo ... i'll just leave it bubbling away

T'Onion wrote:its been on for 48 hrs now , its holding the charge ,

the charger i have has four leds on it , so when the four lights are on its charged , only got two on at the mo ... i'll just leave it bubbling away

Have ya got a voltmeter to stick across it? It might be bubbling away 'cos it's full and all the extra energy is just being used to dry the thing out!