24v (2x 12v)server battery any use in van?

[slippy8v]

picked up a APC 24V 17 amp server battery (2 x 12v mounted together and compact size) had been in my office as a replacement and never used so now being got rid of so i was wondering if it could be used in the van using a 24v to 12v drop down unit and charging from a zig seems a waste to just bin it. meter shows 23.5 volts.Can get a 24v to 12v converter for about £20

Thinking of running LED Lights and usb sockets

[kevtherev]

just rewire the two batteries in parallel
they are in series at the moment

[slippy8v]

D'oh now why did i not know that, just have to get them apart as there stuck with double sided pads.
Thanks

[ghost123uk]

We used to get loads of these type of batteries. ISO9000 regs meant that Banks etc had to swap for new every 2 years, even if there was nowt wrong with the old ones. Companies have to pay to have them recycled (lead and acid inside) so they are only too happy for someone to just take them away = saves them money. I used to have loads of them

Most of them are not a very high Ah rating though

What Ah rating are the ones you have ?

btw, put them somewhere nice and warm for a while and the sticky double sided tape will soften enough for you to lever them apart with a suitable "tool". Be careful not to puncture the cases when doing it though

The remaining UPS circuit (and box) can be used as a pretty good inverter, especially the type that run off just one battery, hence 12 volt input. Plus, if you plug it into the mains (as originally intended) it charges whatever battery is connected

[ghost123uk]

meter shows 23.5 volts

I wonder how long it has been since it (the UPS) was last used ?
If recently, that meter reading indicates one or both batteries are in bad condition (it should read about 25 volts).

You can test them, let me know if you need a "how to".

[slippy8v]

don't think it was ever used just sat in a box. checked again showing 23.7v

17 amp

[ghost123uk]

Going by the size (using the Anderson connector as a reference for scale) I would guess they are in the region of 18Ah. Not really much use as a leisure battery I am afraid. Those type of batteries made by APC have a limit as to how much charge you can safely put into them. It is limited to what is known as ".1C" which means no more than 1/10th of the rated Ah output, so in your case ~1.8 Amps. If they are fairly depleted after use (ie less that 11.5 volts or worse) the alternator can / will produce too much current into them. This would be dangerous. I have seen one of these go bang and it is very scary !

Back to the drawing board I am afraid.

[slippy8v]

worth a try hate to see anything getting wasted.

[syncropatrick]

Cut off the anderson connector. The metal contacts can be slide out and replaced with new ones of varying sizes of cable and ampage. It'll save you a couple of quid. Grey connector I think is good for 50A.

[ghost123uk]

worth a try hate to see anything getting wasted.

Please be careful - see THESE. The one I saw explode was inside a large model boat, being charged up from a running car engine via jump leads. It went off like a bomb and completely destroyed the model boat and sent Sulphuric Acid paste flying out for 10 yards or more (including over the guys car !) Luckily, being at a model boat lake, we had plenty of water to douse everything with. You have been warned (in a friendly way that is )

At least = if you put a car indicator bulb in series with the lead you are going to charge it with, it will limit the current to a safe level (and you can tell when it's charged because the bulb will eventually go off completely).

Your local model aeroplane club will buy them off you. They (we) use them as (external) starter batteries for the bigger model aero engines.

[petethefeet]

I use an ex mobility scooter battery as a second battery, I think it is about 45-50Ah, it is wired up with a 10 amp charge fuse to limit the input current and to date the fuse has not blow. We only use it for charging the phones and LED interior light so not much draw from it.
Photos are scary; I have heard the stories but not see the pictures before
Anybody know of a good quality 12 vd to 5v converter that I can use as a usb supply for phones? Currently using a plug in type one with it wired via fuse to the battery