El-Cheapo UPS Battery replacement: Can I use Lithium (LiPo)?

Budza

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I've got one of these: https://www.takealot.com/rct-850va-line-interactive-ups/PLID32714233

The battery doesn't last more than 30min after 1yr of running ONT + WiFi Router (that's the only load it has).

To replace that, I can buy another SLA battery, but couldn't I just drop in one of these:

104Wh @ R999

OR
140Wh @R1200

Any risks to either the UPS or the battery? UPS voltage when charging SLA is around 13.7V, which I think the LiPo can handle...
 

Geoff.D

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The only way to answer that is to have a look at the spec for the UPS to determine if it can handle the charging current required for the replacement, and whether there is not some or other setting that will in any case cut power regardless of the type of battery installed.
 

rodga

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Also make the sure that the replacement battery will physically fit as well
 

Gnome

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I wouldn't be bothered by anything except the safety aspect.

Lead acid batteries are the most forgiving batteries when it comes to deep cycle & bad chargers. At worst you ruin the battery. They don't catch fire or explode into a fireball.

Lithium in the other hand catch fire if you look at it wrong. They are especially unforgiving of bad chargers and using one without a BMS is guaranteed to cause a fire.

There is a good reason aircraft regulations are super paranoid about lithium based batteries.
Some of the lithium based batteries are safer, but frankly I would keep it in a place where a fire isn't likely to burn down your house

The safety aspect should be super obvious to you unless you have been living under a rock in the last 10 years.
Lithium ignites very easily when exposed to oxygen, unlike lead, so those batteries aren't the easiest to make safe.
 
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Dairyfarmer

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The battery doesn't last more than 30min after 1yr of running ONT + WiFi Router (that's the only load it has).
It can only handle a load of 480w (btw power factor is just 56%!). These UPS's are designed to give devices sufficient time to shut down when power is interrupted and handle fluctuations in power. They are not designed to run devices for a long time. The only reason you are getting 30 minutes is that you have such a light load. But if it is running till it shuts down, you are just killing your battery.

A normal deep cycle battery may be rated at 1600 cycles where depth of discharge (DoD) is less than 25%. i.e. you still have 75% battery left when utility is restored. At 50% DoD you may expect 500 cycles. Anything more than 75% DoD and a battery may not even recover or the cycles drop to 20 or so.

Another thing to consider is that the charging unit in this UPS is designed to charge the batteries supplied and by adding bigger or more batteries, the unit may not be able to fully charge the batteries between cycles. Also, unless the unit is designed for different battery types (unlikely) it may not be able to charge the batteries correctly. Like @Gnome says about lithium, Ka-BOOM!!!

I suggest you rather get the correct power backup solution of what you have. You should maybe be looking at an inverter not a UPS, although inverters can be used in the true UPS scene. You can get a 300watt pure sine inverter for under R1500 and a 12v 100ah deep cycle battery for under R2000. A few hundred more for a good battery charger. At 150watt load a 12v 100ah battery run to a 50% DoD will give you 3.5 hours of power (12x100/150/2x0.85). Most likely the load is less than 100watts so 5+ hours should be expected. Battery should last 3 years at the very least with lots of load shedding.
 

Papa Smurf

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yoh
i would never risk a lithium battery into a lead acid charger
too scared
(and i dont know enough on this subject)

if you dont blow up the house let us know how it went, keen for a review :thumbsup:
 

joshuatree

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If only for router and ONT/CPE get a Omnipower Ratel model from Communica or Sinetech - there are different models. I have the Ratel 430M and bought it at Communica.

Another option is something similar from :

Or just replace the batteries on your UPS.
 

Magnum

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I wouldn't be bothered by anything except the safety aspect.

Lead acid batteries are the most forgiving batteries when it comes to deep cycle & bad chargers. At worst you ruin the battery. They don't catch fire or explode into a fireball.

Lithium in the other hand catch fire if you look at it wrong. They are especially unforgiving of bad chargers and using one without a BMS is guaranteed to cause a fire.

There is a good reason aircraft regulations are super paranoid about lithium based batteries.
Some of the lithium based batteries are safer, but frankly I would keep it in a place where a fire isn't likely to burn down your house

The safety aspect should be super obvious to you unless you have been living under a rock in the last 10 years.
Lithium ignites very easily when exposed to oxygen, unlike lead, so those batteries aren't the easiest to make safe.
Uhm no....Have had some nasty encounters with Lead-Acid batteries whereby they explode and send ACID EVERYWHERE!
 

joshuatree

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Uhm no....Have had some nasty encounters with Lead-Acid batteries whereby they explode and send ACID EVERYWHERE!
So these batteries inside these power trolleys from Mecer and Ellies parked next to one's TV can potentially cause havoc maybe?
 

Magnum

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So these batteries inside these power trolleys from Mecer and Ellies parked next to one's TV can potentially cause havoc maybe?
Chances are slim. Yes they do crack more often than explode like the larger industrial variants we use.

Non liquid batteries are also much safer now and starting to get cheaper. keep em ventilated and and checked regularly. Then you should have no problem.
 

Dairyfarmer

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Lead Acid batteries don't just explode.
They must either be:
Damaged
Shorted out
Overcharged, which goes along with a poor quality charger
And then there is the hydrogen the battery water gives off. If this reaches 4%, I think, it becomes explosive.
 

Tovad

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I've got one of these: https://www.takealot.com/rct-850va-line-interactive-ups/PLID32714233

The battery doesn't last more than 30min after 1yr of running ONT + WiFi Router (that's the only load it has).

To replace that, I can buy another SLA battery, but couldn't I just drop in one of these:

104Wh @ R999

OR
140Wh @R1200

Any risks to either the UPS or the battery? UPS voltage when charging SLA is around 13.7V, which I think the LiPo can handle...
I have been testing a Bluenova 8Ah in a Sherlotronic Backup 12v PSU unit for about two weeks - I posted about it somehere else in this forum.

The Bluenova LiFePO4 are specified to be drop-in replacements for LA
Read:


My measurements to date indicate they may be better suited to these 12volt backups rather than a UPS but you do not seem to require a high current burst from you UPS which will ameliorate the conditions somewhat..

Also remember that they have their own integrated BMS
 
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T-Man

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Just get the Lipo battery, with a suitable charger. Your ONT & Wifi Router probably run on 12V anyway. No need for a inefficient inverter.
 

Gnome

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ACID EVERYWHERE!
It is diluted and more importantly, it nearly impossible to get off the shelf batteries to do that. There are plenty of youtube videos of people actually trying to get lead acid batteries to explode, it isn't easy. Lastly, assuming you store your batteries open so that said acid can go everywhere, you actually need a human there for it to be a seriously bad situation.

I have to say I can't really take you seriously. You are trying to compare something that has a very low probability, near 0, to something that has a pretty significant probability and doesn't even need humans around to be very dangerous.
 

Papa Smurf

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Then YOU did something very, very wrong to those batteries.
agree 100%
i have never seen a lead acid explode or anything
worse case scenario it swells up the casing and stops working
weird egg smell and thats it

lithium on the other hand, i am scared Yes

Image result for battery explosion gif
 

Magnum

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It is diluted and more importantly, it nearly impossible to get off the shelf batteries to do that. There are plenty of youtube videos of people actually trying to get lead acid batteries to explode, it isn't easy. Lastly, assuming you store your batteries open so that said acid can go everywhere, you actually need a human there for it to be a seriously bad situation.

I have to say I can't really take you seriously. You are trying to compare something that has a very low probability, near 0, to something that has a pretty significant probability and doesn't even need humans around to be very dangerous.
Anything greater than 0 has a chance of happening. Also the battery chargers we use are the kind that gets moves around with a forklift.

The other set of batteries has a 10 Ton crane moving them, and they are wired with cables I can't even bend. I stay mostly out of the workshops.
 

The_Traveller

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Uhm no....Have had some nasty encounters with Lead-Acid batteries whereby they explode and send ACID EVERYWHERE!
Don't know what you were doing to your batteries for it to explode, but my ( ignorant ) cousin had this battery in a cabinet blowing up for weeks. He's charger was fvcked.
 

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