LiFePO4 cells are not as dangerous as other lithium batteries (they don't catch fire and just burn), but there is still a fire risk if you charge too fast or too high.

I wouldn't do this in the home without doing the tests below, but having said that, I wouldn't object to doing it in the factory: our factory has several other fire risks and managing fire risk is part of why we have a factory.

The float voltage is reasonable: it won't overcharge the cells, and will keep them reasonably full. It doesn't matter that the cells remain on float because you aren't taking them up close to fully-charged.

So direct replacement is reasonable as long as you don't need to use the UPS (which, to be fair, is the normal case for many UPS -- it may go for years before you need it).

What you haven't told us is the charge rate of the UPS, or the float range, or the boost voltage, or if it is a 4 or 5 state charger (unlikely).

If, after the cells go partly flat, because they've been supporting the load for 20-200 minutes, the system tries to recharge too fast, or (less likely) tries to boost too high, then you could overheat and damage your cells.

You can probably find an estimate of how fast the UPS tries to charge by finding how long it takes to recharge after use, which is probably documented. And your LiFePO4 cells will have documentation for the charge rate.

You can also just measure the charge current with your existing cells, if you want to open up the UPS and use a DC clamp or in-line ammeter. And you can check the float range, and check to see if there is a boost voltage with a voltmeter.

LiFePO4 cells are not as dangerous as other lithium batteries (they don't catch fire and just burn), but there is still a fire risk if you charge too fast or too high.

I wouldn't do this in the home without doing the tests below, but having said that, I wouldn't object to doing it in the factory: our factory has several other fire risks and managing fire risk is part of why we have a factory.

The float voltage is reasonable: it won't overcharge the cells, and will keep them reasonably full. It doesn't matter that the cells remain on float because you aren't taking them up close to fully-charged.

So direct replacement is reasonable as long as you don't need to use the UPS (which, to be fair, is the normal case for many UPS -- it may go for years before you need it).

What you haven't told us is the charge rate of the UPS, or the float range, or the boost voltage, or if it is a 4 or 5 state charger (unlikely).

If, after the cells go partly flat, because they've been supporting the load for 20-200 minutes, the system tries to recharge too fast, or (less likely) tries to boost too high, then you could overheat and damage your cells.

You can probably find an estimate of how fast the UPS tries to charge by finding how long it takes to recharge after use, which is probably documented. And your LiFePO4 cells will have documentation for the charge rate.

You can also just measure the charge current with your existing cells, if you want to open up the UPS and use a DC clamp or in-line ammeter. And you can check the float range, and check to see if there is a boost voltage with a voltmeter.

If you don't want to do that ... well, LiFePO4 cells normally have a higher charge rate than Lead Acid batteries, so you could take a chance -- at least read the documentation and make an estimate.

LiFePO4 cells are not as dangerous as other lithium batteries (they don't catch fire and just burn), but there is still a fire risk if you charge too fast or too high.

I wouldn't do this in the home without doing the tests below, but having said that, I wouldn't object to doing it in the factory: our factory has several other fire risks and managing fire risk is part of why we have a factory.

The float voltage is reasonable: it won't overcharge the cells, and will keep them reasonably full. It doesn't matter that the cells remain on float because you aren't taking them up close to fully-charged.

So direct replacement is reasonable as long as you don't need to use the UPS (which, to be fair, is the normal case for many UPS -- it may go for years before you need it).

What you haven't told us is the charge rate of the UPS, or the float range, or the boost voltage, or if it is a 4 or 5 state charger (unlikely).

If, after the cells go partly flat, because they've been supporting the load for 20-200 minutes, the system tries to recharge too fast, or (less likely) tries to boost too high, then you could overheat and damage your cells.

(I say "partly flat" because a UPS designed for lead-acid cells will cut out long before the LiFePO4 are actually flat: that cell chemistry can continue to provide power where a lead-acid battery would be permanently damaged by over-discharge.)

You can probably find an estimate of how fast the UPS tries to charge by finding how long it takes to recharge after use, which is probably documented. And your LiFePO4 cells will have documentation for the charge rate.

You can also just measure the charge current with your existing cells, if you want to open up the UPS and use a DC clamp or in-line ammeter. And you can check the float range, and check to see if there is a boost voltage with a voltmeter.

LiFePO4 cells are not as dangerous as other lithium batteries (they don't catch fire and just burn), but there is still a fire risk if you charge too fast or too high.

I wouldn't do this in the home without doing the tests below, but having said that, I wouldn't object to doing it in the factory: our factory has several other fire risks and managing fire risk is part of why we have a factory.

The float voltage is reasonable: it won't overcharge the cells, and will keep them reasonably full. It doesn't matter that the cells remain on float because you aren't taking them up close to fully-charged.

So direct replacement is reasonable as long as you don't need to use the UPS (which, to be fair, is the normal case for many UPS -- it may go for years before you need it).

What you haven't told us is the charge rate of the UPS, or the float range, or the boost voltage, or if it is a 4 or 5 state charger (unlikely).

If, after the cells go partly flat, because they've been supporting the load for 20-200 minutes, the system tries to recharge too fast, or (less likely) tries to boost too high, then you could overheat and damage your cells.

You can probably find an estimate of how fast the UPS tries to charge by finding how long it takes to recharge after use, which is probably documented. And your LiFePO4 cells will have documentation for the charge rate.

You can also just measure the charge current with your existing cells, if you want to open up the UPS and use a DC clamp or in-line ammeter. And you can check the float range, and check to see if there is a boost voltage with a voltmeter.