5 Must-Have Features in a LiFePO4 135Ah Lithium Battery

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Hello, I recently purchased a battery through Walmart.com. It was advertised as a 36v 135ah Lifepo4 battery. The battery arrived pretty quick, well packed and in new condition. It is currently connected to my 36v solar system. It seems to be working fine (charging and discharging normally). Here's the thing that bugs me: The label on the battery and in the manual states the battery is lithium ION, not IRON. I'm hoping those are typos but I don't know. Nowhere does it state the battery is Lithium IRON except in the original ad. The same company is also selling the same battery at the same price on Amazon where title also says the battery is IRON but the details say ION. What do you think? Could this be a big red "don't buy" flag?

Hello, I recently purchased a battery through Walmart.com. It was advertised as a 36v 135ah Lifepo4 battery. The battery arrived pretty quick, well packed and in new condition. It is currently connected to my 36v solar system. It seems to be working fine (charging and discharging normally). Here's the thing that bugs me: The label on the battery and in the manual states the battery is lithium ION, not IRON. I'm hoping those are typos but I don't know. Nowhere does it state the battery is Lithium IRON except in the original ad. The same company is also selling the same battery at the same price on Amazon where title also says the battery is IRON but the details say ION. What do you think? Could this be a big red "don't buy" flag?

I assume it is a no-name brand. As such you are justified in being concerned.

Does the manual give instructions on charge voltage? That can be a give-away that is NMC vs LiFePO4.

I assume it is a no-name brand. As such you are justified in being concerned.

Does the manual give instructions on charge voltage? That can be a give-away that is NMC vs LiFePO4.

The specs provided with the battery do not indicate any battery chemistry. However, the specs do mention "Charge voltage: 43.8+0.2v calculated according to 3.65v for each cell. Standard charge current: 0.2C. Max. charge current: 0.5C".

In another section, the "guidelines for use" states (if a 12v system) "the charging voltage should conform to the voltage of 14.6+/-0.2V AC-DC charger".

In another section, it states charge the battery "with a 14.6V LIFEPO4 charger".

On the battery, however, there are 2 labels with no branding whatsoever. One "do and don'ts" label states "Do not mix different lithium ION batteries." And the I.D. label states "Model: 38.4V135AH. Voltage: 38.4".

Too much contradiction with this battery/vendor. And I really want to be be sure I have an Fe battery because my understanding is that they are more stable and significantly less prone to catching fire. Thanks for your help. A charging voltage of 43.8V @ 3.65V would mean only 43.8V/3.65 = 12 LiFePO4 Cells.... that would be bizarre.
A nominal voltage of 38.4V would mean 38.4V/3.2 = 12 LifePO4 cells. That aligns with the charge voltage but is still bizarre.

I don't know what that battery is..... but it does not appear to be a normal LiFePO4 48V battery. The weird thing is that it does not appear to be a normal Lithium-ion (NMC) battery either.

Can you open it up without damaging it?

Edit: As pointed out by others, it appears to be a LiFePO4 36V battery.

A charging voltage of 43.8V @ 3.65V would mean only 43.8V/3.65 = 12 LiFePO4 Cells.... that would be bizarre.

Indeed. However, it's entirely understandable if someone asked for charging voltage per cell and was answered "not to exceed 3.65v/cell", so they cleverly did the math. I'd read that as "the BMS will take the battery offline at a MAXIMUM of 43.8V, so don't bother to try to charge it higher than that".

Honestly, if someone gave me that battery I'd ship it off to Will in a kinda of reverse-raffle and let him tear it apart.

Can you try for a refund?

A charging voltage of 43.8V @ 3.65V would mean only 43.8V/3.65 = 12 LiFePO4 Cells.... that would be bizarre.
A nominal voltage of 38.4V would mean 38.4V/3.2 = 12 LifePO4 cells. That aligns with the charge voltage but is still bizarre.

I don't know what that battery is..... but it does not appear to be a normal LiFePO4 48V battery. The weird thing is that it does not appear to be a normal Lithium-ion (NMC) battery either.

Can you open it up without damaging it?

My thoughts exactly: Bizarre. Thinking about a maybe getting my money back so I won't be taking it apart.

Yeah, it's LFP, the disconcerting part is the vendor doesn't seem to know much about batteries. Still, it ought to work just fine as an LFP, for values of 'batteries from clueless vendors who probably won't be around next year'.

To me it's a guessing game. Considering all the contradictory info, what would tell me without any doubt what's inside without ripping it apart?

There's no doubt it's LFP. Which one did you get specifically? Looks like there are a bunch of similar batteries on WalMart. Or ask here for recommendations for 36V solar LFP batteries. What inverter do you have?

The battery is no longer on Walmart.com. I purchased the "last one". But the same vendor is selling a battery with the same specs on Amazon. Here's the giant link to it (hope it works) https://www.amazon.com/PUPVWMHB-LiF...59&sprefix=36v+135ah+life,aps,114&sr=8-3&th=1

Note part way down the ad column, it states "Battery Cell Composition: Lithium Ion"

There's no doubt it's LFP. Which one did you get specifically? Looks like there are a bunch of similar batteries on WalMart. Or ask here for recommendations for 36V solar LFP batteries. What inverter do you have?

Well, the link was "giant" before I posted it. Anyway, I have a 36v in 120v out, w pure sine inverter that's been serving me well for several years. But I go easy on it too.