Author Topic: How many Amp/Hrs are these?  (Read 1340 times)

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olvvlo

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How many Amp/Hrs are these?
« on: May 23, 2006, 07:52:37 AM »
can anybody tell me how many amp/hrs these battery is maybe?

They measure 30x30x16cm and are both 6v.





I acquired them off a friend who said a year ago the electrolyte was replaced after they had dried up!  He then left them uncharged for the rest of the year!

I checked the voltage when I got home and each cell registered about .9V giving 2.7v per battery.

I put them on charge overnight wired in series for 12v with the charger indicating about 7 amps.

This morning they were drawing 3 amps. Each battery reading 6.7 volts.(13.4v)

Is this an indication that they may be good still?

and/or is there anything else I could do that may save tham?

There are two more batteries making a total of four and therefore could save me a lot of money.
« Last Edit: May 23, 2006, 07:52:37 AM by (unknown) »

thunderhead

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Re: How many Amp/Hrs are these?
« Reply #1 on: May 23, 2006, 04:24:23 AM »
If they drew 7A overnight (12 hours) they'd be 7A x 12h = 84Ah.  If they drew an average of 5A overnight, they'd be 5A x 12h = 60Ah.


If that's good or not probably depends on how much lead there is in them: my 12v/100Ah batteries weigh about 40kg, so if your batteries weigh the same they should be capable of storing something around 200Ah.


Keeping them on a good float charge for a while might help them, or you might try pulse-charging them or zero delta voltage charging them.  Circuits to do this can be found by searching through this site.


But the fact that they drew 7A on charge is a good sign -- lead acid batteries tend to die by sulphation, which prevents them from being charged.

« Last Edit: May 23, 2006, 04:24:23 AM by thunderhead »