'Priming' old UPS batteries

[Seri]

It's a touch overkill and perhaps a little OT too, but it does seem the kind of thing that a few people here will know about.

I managed to obtain an old(ish) APC 5000 Smart UPS (5000VA/3750W) and wired it into the mains last night. I purely intend the device to provide backup power and mains cleaning for the boiler, telephone, DSL modem/router and Wireless AP so it will have a teeny load on it.

Anyway, it has the original lead/acid batteries that came with it, that seem to still be holding a charge, but they're not great and lose their charge really quickly. I've pulled one of the batteries out of the chassis to see if there was any hope of toping it up like a car battery, but no dice (not that I was suprised).

Does anybody know of a way of 'priming' this type of battery to make it healthier? Is it worth me charging them up full and then discharging them as much as possible a few times? Or should I just leave them constantly charging?

As always, thanks for any and all responses.

Seri

[Chris Bacon]

They're scrap, the plates will be sulphated, or possibly shorting. You can get "Bat-Aid" tablets at car shops which may make the batteries better for a while (if you can get them in), but I think you'd be better off just replacing them. You don't have to use the same physical sized ones.

[dingbat]

Try buying part-used batteries on the geek surplus market (helps to be local too). They're rated at a 10 year life but "real" UPSes often swap them at 5. I've bought massive cells (twice the size of a car battery cell) at =A31.50 each in the past, although I was buying a ton or two.

And I wouldn't trust APC kit as far as I could throw it. I've never had a project with APC kit where they _haven't_ failed in a manner that boiled the battery and dumped acid either onto the client's carpet, or into a 19" rack cab full of kit.

[Simon Barr]

The batteries will most likely be knackered. They only last 2 - 5 years on average. You will just have to replace them. I always try to use Yuasa ones, others don't seem to have the same lifespan.

CPC seem to consistently be the cheapest too.

HTH

[Phil]

The battery for this will be made up of lots of batteries all in series to make up a high DC voltage. If you are lucky, you may find that only one or two of the individual batteries may be shot - you need a high discharge rate amp hour meter in addition to just measuring the open circuit volts.

Beware the high DC voltages that lurk within!

[Seri]

I'm looking at replacing them, but the damn thing takes 16 of them wire up in blocks of 4, the cheapest price for the same or equivalent I can find is =A318 each. So just shy of =A3300 is a little more than I wanted to spend at the moment....

Of course, if anyone knows where I can locate 16 cheap Panasonic R127R2P1 or equivalent batteries from then that would be great! :o)

Thanks again

Seri

[Simon Barr]

I wouldn't bother with used, you just can't be sure what you're getting.

Yuasa rate their batteries at 5 years on standby.

I've *never* known any UPS to boil batteries and dump acid and I've replaced batteries in maybe 50 over the years. Some of them were very deformed from high temperatures but all held onto their contents.

You must be very unlucky!

[Simon Barr]

Is that a 12V 7Ah?

The Yuasa equivalent from CPC is £12.79ea if you by more than 10.

Still a lot of cash though!

[B Thumbs]

What voltage and how are they connected. A car battery or two may do.

[Seri]

The current Panasonics are 12V 7.2Ah so I'm presuming the Yuasa ones would do the job. May have to order a few from CPC and see if I can isolate which ones are 'most' dead in the current blocks.

Thanks!

Seri

[Bob Eager]

What's the exact model number? (of the UPS)

[Andrew Gabriel]

They are probably knackered. In a UPS, the capacity of the batteries drops pretty linearly to zero after about 5 years, so they're usually chucked out at about 3 years when the run time will have got too short for the original application. Usually, the cheapest way to replace them when integrated inside the UPS is to buy a new UPS;-)

[Dave Liquorice]

Ask Bristol Batteries. Good price when I need to replace the two 12v

7A/hr jobbies in my small UPS.

the colour scheme, not.

[Seri]

Well, just slid the thing forwards on the platform I made for it and on the back it says it's a SU5000RM15U

I haven't yet hooked up to it with a console cable to see if it gives a more precise model number.

Is that the number you were after?

Thanks

Seri

[Rob Morley]

Lead-acid batteries don't like to be fully disharged and they don't have "memory" like some other rechargeable chemistries. As yours are sealed you can't use magic reviver potion in them (not that I'm convinced that it works very well anyway). So you're going to have to find some new batteries - if you're not bothered about it fitting in the case you could atach any battery of the correct voltage and about the right capacity, otherwise you can buy "proper" batteries from a specialist supplier. Don't try using a battery of significantly greater capacity as this may damage the charging circuit.

[Gordon Henderson]

It might actually be worth while contacting APC directly and seeing they have have deals for resurecting old batteries, or exchange programs. A place I work with has done this in the past with good results.

Gordon

[Bob Eager]

Oh well. Looking up brand new batteries, they're 246 quid each (and I think you need two, is that right?)

[bigcat]

options:

1. open them and replace the electrolyte. This often gets lead acids working well again, and costs peanuts
2. buy new set of deep cycle batteries
3. buy car batteries and know theyll be dead after 500 cycles
4. Make some new batteries, using either the scrap lead from the old, or roofing lead sheet. Its not hard.

NT

[Seri]

The damn thing takes four! At full capacity I think I could run the freezer and electric oven off it (not that I would want to you understand).

But yes, that's way more than I plan on spending for something that SWMBO classes as 'one of his projects'....

[Bob Eager]

Ha! Problem...

For the record, I have bought two (much smaller) APC battery packs recently. The 'pattern' ones weren't much cheaper than APC ones and were of fairly unknown quality. I had no time to make them up, either.

Cheapest place, with FREE carriage (not insignificant) was Amazon. Just for the record...