Replacing Batteries on Small UPS

[CodeJBDA]

Hi All,

I was thinking about the most economical to fight this load shedding, these small UPS system are not the most robust however they are quite good at keeping things up and running. For example, I have a Gizzu UPS for my router and ont. I was wondering if it is possible to replace the batteries in these systems, to increase the systems lifespan?

 

[pikolec]

It may be possible, depending on the unit. The ratel units have 4 or 8 x 18650 cells in them soldered to nickel strips. So it is possible, but not easy.

oh, and you can find 18650 cells that have a much higher rated capacity which means that you can increase the duration that it keeps the flashing lights on .

top tip- 18650 cells top out at about 3500mAh. Anything over that is probably a scam. Best to go with know brands (lg, Samsung) branded cells and read up about li-ion safety,

it may also be possible to use larger 21600 cells which can can be 5000mAh which would double the available stored energy. Post your projects here!

 

[YpieM]

I stripped a normal 650 watt mecer ups and replaced the small 7ah battery with two big 40ah batteries. It only keeps my pc on for 2 hours and while I'm gaming only about 40 mins. I did the same for my mom but with 2x18ah batteries. She uses a laptop with a 32 inch monitor and she now gets through a 2 hour loadshedding with ease. If it is 4 hours then she has to run the laptop on battery life otherwise the systems battery gets drained.

 

[Confucius]

I had a 2000va ups that had 2 internal batteries. I eventually added a cable to the outside and added another 2 external batteries. Worked fine.

Only problem with adding too big batteries is that it takes much longer to recharge the batteries.

 

[CodeJBDA]

Interesting! I like the idea of simply replacing the batteries in a UPS/inverter system that powers basic things. For example, I thought of have a Mini UPS under my bedside table and figuring out how to power my chargers and lamp to it.
My worry is that the batteries would give out, but if they are not expensive to replace (and possibly even upgrade) then that would nip that problem. I'm toying with a solar option but at R150 000, I dunno if I have the appetite.

 

[YpieM]

According to all of the research I have done, "going solar" isn't really worth it. R 150 000 is most likely just a small system that will power lights, computers and tvs unless you get really cheap batteries and install everything yourself. In the long term you won't save much on your electricity bill and R 150 000 to get rid of loadshedding is a lot. I have a ups with external batteries for my pc, as mentioned above, and I have a few solar light kits around the house (R 400+- on takealot). A small gas bottle and kettle and a small ups for my wifi. The solar kits and ups can charge my phone if/when needed. To get all my essentials running during loadshedding cost me around R 3000. I am thinking of adding a solar panel and charger to my pc ups system so the batteries last a bit longer and charge a bit faster.

 

[CodeJBDA]

According to all of the research I have done, "going solar" isn't really worth it. R 150 000 is most likely just a small system that will power lights, computers and tvs unless you get really cheap batteries and install everything yourself. In the long term you won't save much on your electricity bill and R 150 000 to get rid of loadshedding is a lot. I have a ups with external batteries for my pc, as mentioned above, and I have a few solar light kits around the house (R 400+- on takealot). A small gas bottle and kettle and a small ups for my wifi. The solar kits and ups can charge my phone if/when needed. To get all my essentials running during loadshedding cost me around R 3000. I am thinking of adding a solar panel and charger to my pc ups system so the batteries last a bit longer and charge a bit faster.

I'm tending to agree with this logic. Obviously everyone has different usage, but I was actually thinking of doing this too. Having a decent size UPS/Inverter for my PC and Entertainment.

 

[ClintT]

I had (still have i think) a small RCP (mecer) UPS with a 7ah battery. Used that to just keep the internet on. We had a few rechargeable lights.

But, then i bought a Synapse 3.0Kva inverter with 2 agm batteries and wired all lights and a couple plugs to it. 8 months later, i replaced the agms with 2 lithiums. Still going strong since we put in a gas stove, loadshedding does not impact us at all.

Synapse inverter: ~R5000
AGM batteries: ~R5000
Cabling, switches and trunking: ~R3000
Installation: R2500

Later, 2 lithium batteries: R11000.

 

[Centurion_Oke]

Only problem with adding too big batteries is that it takes much longer to recharge the batteries.

So I guess two external 100Ah external deep cycle batteries won't work too well?

I went the same route as you, also a 2va UPS, ending up with 2 external 7Ah batteries. I found what eventually destroys it are batteries getting out of balance, one battery destroying the other in each string.

Then I got some old good condition 100Ah batteries. Essentially it kind of works, except for the obvious long charge time if used for too long. Inefficiencies also sees these eventually draining. Not so obvious is the charging voltage, also batteries getting out of balance. So I charge them up manually regularly.

My thoughts currently are for an external 24v battery charger, battery balancer, switched via a dual pole two way relay powered from the mains input side. The internal batteries just have to hold power long enough to have the external batteries kick in. Obviously some type of relay contact protection will be needed to prevent arcing. All built out of salvage bits and pieces.

 

[Confucius]

So I guess two external 100Ah external deep cycle batteries won't work too well?

I went the same route as you, also a 2va UPS, ending up with 2 external 7Ah batteries. I found what eventually destroys it are batteries getting out of balance, one battery destroying the other in each string.

Then I got some old good condition 100Ah batteries. Essentially it kind of works, except for the obvious long charge time if used for too long. Inefficiencies also sees these eventually draining. Not so obvious is the charging voltage, also batteries getting out of balance. So I charge them up manually regularly.

My thoughts currently are for an external 24v battery charger, battery balancer, switched via a dual pole two way relay powered from the mains input side. The internal batteries just have to hold power long enough to have the external batteries kick in. Obviously some type of relay contact protection will be needed to prevent arcing. All built out of salvage bits and pieces.

If you going big external batteries then it’s better to also have a bigger external charger but ideally if you are using 2x100ah, then you rather remove the internal batteries and just use the externals.

Agree on the balancer though. This is needed.