I have an UPS with two 12v 7ah lead batteries. If I want to change the batteries I would typically go with lead batteries but here’s my question, can I use some portable mobile power banks to use it?
Because I have a 20000mah “INUI” lithium power bank that is rated for 12v at 1.5A, is it a good practice to buy several of these (since they are about 20 bucks) disassemble them and use them as ups batteries?
EDIT : clarifications
Different chemistry and voltage levels, power banks use Li-ion which is 3.7V nominal per cell, and the UPS needs a 12V nominal battery which you can’t get with Li-ion cells since 3x = 11.1v, and 4x = 14.8v.
However in some UPS models you can replace the batteries with LiFePo4 replacements, as that chemistry does match the voltage and charge profile (at least close enough). If it works or not depends on the UPS and if it complains about the slight differences.
You need a balancing BMS anyway and the UPS will not be able to charge it to what it thinks is 100% (about 15 V at trickle current) unless you trick it with a resistor (which wastes power of course).
Yeah you need a UPS that’s OK with the BMS charge FETs opening when the battery is full.
When there is no trickle current the UPS will beep because it will detect battery removal.
Some are ok with it, on a thread I saw on reddit awhile ago about LiFePo4, people had reported a few models that worked fine with the upgrade.
I’m not that good in electricity but basically are lithium batteries from power banks would work the same as 12v lead car batteries?
No they’re different voltages.
On the paper they are 12v, so what makes the real output voltage
3s would be 11.1v and 4s is 14.8v, so I’m not sure where you got 12v from.
It is written on the back of the powerbank (sorry but I’m not so good in electrics)
If you’re this confused you shouldn’t be trying to change battery types in a device that can power appliances.
Yeah for now I will stay with lead batteries thx
Ah gotcha, that’s the regulated 12V output with USB PD mode, and not the voltage of the battery inside.
Ohhh okay, sad… Is there a way to get these 12v to use it instead of the stock lead batteries?
Not easily or cheaply, because of the voltage mismatch. Using a buck / boost converter setup tuned specifically for the UPS might work but would be pricey and probably not that reliable.