UPS uninterrupted power supply / deep cycle / solar batteries

I have a friend that has constant brown outs, he has 2 x UPS units that will not go the distance with his computers, I had a brain wave to fit an external battery on the UPS to raise the amp hours, the internal battery is 12v 4.5 amp hour so I am considering a 100amph external battery supply which in theory should give me over 20 times the current life, has anyone done this already?? The only problem I foresee is the internal charger, if the battery amp hours is 20 times the original what is the charging time of the larger battery?? I will see if I can check the current output of the internal charger. Another way around the internal charger is to use an external charger.

Where do I buy deep cycle batteries in Duma?

 

Most deep cycle batteries don't like to be more than 50% drained before charging. You can go down to 20% but it shortens the life of the battery. For the most durable deep cycle batteries, use a golf cart battery. I have used these in the past with very good reliability and longevity. At 50% drain, it shouldn't take more than 12 hours to completely recharge it and have it ready to go for the next day even using a common cheap variety of battery charger that you might have around the house for your car or motorcycle battery.

These types off batteries are also used on motorized dock carts, so maybe a marine supply or parts store would have them.

 

if memory serves me they should not be drained below 11.7 volts 30% which is what you said Larry

 

I had a inverter that was fully automatic it had a large external battery that ran 2 pc,s and a fan for 5 hours they it was about 19th peso it was made in Cebu, worked well , I got it from Ace logic(over the road from pasta king
cheers

cheers

 

Take a 12 volt lead-acid battery and extend the UPS leads out to it.

You should be fine.

 

yea done that, got a 100amp hour deep cycle battery, just hope it extends time as it did on paper. as far as I can see an UPS is basicly an inverter

 

Deep cycle batteries are good but the lesser amp battery will shorten the output life of the greater amp vattery if the greater amp battery doesnt first cause overload issues into the lesser amp battery and if they are different type of cathode & anode materials,funny things can happen in gassing and indoor use is worrysome should gassing in funny ways happen..new battery materials are not meant to be chained in with other batteries of other materials......if they are the same type of anode & cathode material at the core,then the high amp battery will soon turn into the same amp level as its chain partner and it will last its full life term but only at a reduced out put,and thats if it doesnt first over whelm the self contained lower amp units charger ccontroller and whatever other manageing systems it has...my golf cart battery system still powerful after 10 years but i was taught by university course that my added new batteries to old ones reduced the new ones overtime to the out out of the older batteries...its so in any case of uneven batteries chained together....

 

yea thought of that, removed the internal 7.5 amph battery, the ups now has 6mm external cables to the 100 amph battery

 

Ah good,didnt know what you have ,to know removal and reconfigureing could work.....Electro plateing effect is always an issue when running different metals or mineral like stuff related to metals atomically,running them with acid solution in the electrical mix....my battery terminals always built up a blue and bit yellow crystal stash around the terminals,terminals are not copper or lead,the connector cables are copper and contribute the blue crystal formation and the sulphuric acid contributes the yellow crystal formation and not sure about what and if the lead contributes any thing through this electrolytic process......This is what is problematic when chaining lithium based with cadmium,and/or nickel or lead based batteries;the electroplateing process can have strange if not deadly compounds born on the terminals or gassed into air,and thats if you dont get a hybrid reaction that accidentally invents a blackhole or fission/ fusion and blow or suck the whole island to fukushim...well not that bad but you never know what the electrolytic interaction is going to do with too many weird metals in the acid mix...

 

hemmm the 100 amph battery only lasted 40 minutes the UPS must shut down the supply early, apparently there was still 12v in the battery