Model Boat Mayhem - Forum

Technical, Techniques, Hints, and Tips => Batteries & Chargers => Topic started by: KitS on April 02, 2019, 04:28:59 PM

Title: Ancient sealed lead acid batteries
Post by: KitS on April 02, 2019, 04:28:59 PM
I've found a couple of SLA batteries in my loft, both are Microlyte Plus 12V 7.2 Ah types and I suspect both are well past their 'scrap by' date.

The voltage of both of them is around 3.8 - 4.2 V and no amount of charging seems to change that, as soon as I disconnect the charger they go back to the same level.

Are they any use at all, and if so how can I restore them?

I could use them as ballast I guess  :-) but maybe it'd be best to take them to the tip.
Title: Re: Ancient sealed lead acid batteries
Post by: John W E on April 02, 2019, 05:21:51 PM

As Tonto said to the Lone Ranger  TO THE DUMP TO THE DUMP  TO THE DUMP DUMP DUMP, they must go as the poor old things are well past  sell by date  ok2


and if the voltage is as low as 3.2 volt - not even a Flair  pulse charger will bring them back to life :-)
(Flair pulse chargers pulse the output voltage when charging )




john
Title: Re: Ancient sealed lead acid batteries
Post by: KitS on April 02, 2019, 05:27:02 PM
Thanks, as I suspected.  :-))

I'll get a couple of new ones, I must have had SOME ideas for them............
Title: Re: Ancient sealed lead acid batteries
Post by: Capt Podge on April 02, 2019, 05:45:02 PM
Dead SLA's also come in handy when extra weights are needed for holding down decks etc while glue is going off, so if you have room to store them, they are worth holding onto  :-))


Regards
Ray
Title: Re: Ancient sealed lead acid batteries
Post by: DaveM on April 02, 2019, 05:51:53 PM
As Ray says, they're useful as things to put on top of other things that need holding down flat while glue dries.......or as things that hold other things at right-angles to the bench while glue dries.........or as ballast.......or doorstops........ or something to throw at the neighbour's cat. In fact they're more useful when they're dead than they ever where when they weren't!
I just wouldn't let one anywhere near a model of mine.
DM
Title: Re: Ancient sealed lead acid batteries
Post by: KitS on April 02, 2019, 06:13:01 PM
Hm, yes, maybe I won't be off to the tip then, thanks.  :-))

As for room to keep them, my loft is MASSIVE! It has clear space the entire width of my 3 bedroomed house and maybe 12-14 ft between the verticals. One advantage of an 1850s build house.  :-)
Title: Re: Ancient sealed lead acid batteries
Post by: gingyer on April 02, 2019, 06:17:52 PM
if you are binning old SLA batteries check your local scrap yard  :-))


a few years ago at work I was tasked to make about 5000 (yes FIVE THOUSAND) batteries 12v12A or 12v24A disappaer
I was getting 1.50/kg for a SLA battery a few years ago... a 12v 7A weights approx 5Kg  %)


its better in your pocket than someone else's!



Title: Re: Ancient sealed lead acid batteries
Post by: KitS on April 05, 2019, 03:54:31 PM
Thanks for the advice gentlemen, I've redirected the old batteries to be either ballast weights or clamps, and bought two new ones today. They're EXACTLY the same size as the old ones, so whatever it was I had planned for the old ones will still work.

All I have to do is remember what it was...........  {:-{