LiitoKala LiFePO4 batteries with a claimed capacity of 30 Ah

I already had a review of LiitoKala batteries with a claimed capacity of 32 Ah, but those were sent to me by one of my readers. This time I bought similar batteries myself, though with a different claimed capacity and from a different seller.
In short, things aren't looking too good. Read on for the details.


There are lots of similar batteries for sale. In this case, I chose based on price and size, planning to cram fit them into a relatively small space—but more on that another time.
At the time I ordered, they cost $17.11 each. Since I bought them during the 11.11 sale, I was able to use a $6 coupon, bringing the total for four to $62.44, which I think is a pretty good deal.

The package took a very long time to arrive, and by the time I received it, the order protection period had expired and the order had automatically been marked as delivered. I didn't ask the seller to extend the protection, since the package was still moving. On its way from China, it passed through Kazakhstan, Belarus, and Poland before finally reaching Ukraine.

The box was dented on one side, but the batteries were packed very well, so I have no complaints there.


The product page has something like a specifications section, though it's very limited.


Unlike the previous ones, these have a label showing the capacity and the company that repackaged them. One battery has a different color of heat-shrink tubing, and there are also some strange stains, especially noticeable on the one on the left.

I wrote the numbers on the labels and cases while unpacking them, so I could identify each one for testing.


The listed dimensions are 20 × 110 × 140 mm, but that's clearly a typo: the battery model is 20100140, i.e. 20 × 100 × 140 mm. The actual dimensions were roughly as expected, except for the length, which is given without the terminals. With the terminals, it's closer to 145 mm, so keep that in mind when choosing.
The batteries vary in weight: the lightest is 578 g, the heaviest 602 g. The listing says about 650 g.


The terminals are constructed just like the previous ones: the terminal itself is aluminum, with strips of nickel or nickel-plated steel welded to it. I didn't investigate which.
They also clearly skimped on the heat-shrink tubing; batteries like these are usually wrapped right up to the terminals.


And, just like before, the claims about the welded strips are misleading. In the seller's photo, they're clearly wider, apparently to make it easier to connect the batteries into a pack. In reality, they're even narrower than the terminals themselves.


1. There are clearly more weld points. They're along the short side, but arranged in two rows and spaced more closely together.
2. On at least one terminal, the welding machine settings were clearly way off—the strip is literally burned right through. By the way, I tried welding one like this myself and couldn't get it to work. I later found out that nickel strips are usually welded to aluminum with a laser machine. I want one of those...
3. The insulating tape has also come unstuck on one of the batteries.
4. And I have some complaints about the cases. One battery has a noticeable pin-sized dent, though it's a shame I can't show it properly in a photo. All the batteries also have small bumps or dents of some kind, which you can feel as little raised spots.


I tested all four batteries, first running a conditioning cycle consisting of a charge, discharge, and recharge at 15 A.
Even at this stage, it's clear that the batteries were almost completely discharged to begin with, and that their capacity doesn't match the claim.

There's a typo in the graph title: I wrote LiPePO4 instead of LiFePO4.


But there's a bigger problem: the capacities vary considerably. During the preliminary test, battery No. 2 delivered 26.51 Ah (84.89 Wh), while No. 3 delivered only 24.45 Ah (75.35 Wh), which is 8.5% less.


The listing specifies a standard charge at 20 A and a fast charge at 40 A. I didn't want to push the batteries too hard, so given their lower capacity, I tested charging at 15 and 30 A. Besides, those currents are closer to 0.5C and 1C for the claimed 30 Ah capacity.

At 15 A, charging took 1 hour 50 minutes.


At 30 A, charging took 57 minutes, so I can say they accept a charge well. The steep rise at the end of the cycle is also noticeable; with heavily "worn-out" batteries, this part of the curve is flatter.


I tested them in four modes: 0.2C, 0.5C, 1C, and 40 A, where C = 30 A.

No miracle here: the very first battery under test delivered 26.29 Ah instead of the claimed 30.


The second one had the highest capacity, but even it didn't reach 27 Ah, i.e. The actual capacity is no more than 90% of the claimed capacity.


The third one was the weakest, and this showed up not only in its capacity in Ah, but also in its voltage, which in turn reduced its energy output in Wh.


The fourth one performed similarly to the first, so the biggest difference is actually between the second and third.


Heating was moderate, even at 40 A, reaching about 40–42 degrees.


For comparison, I plotted the results for all four batteries on one graph at discharge currents of 6 and 40 A. Oddly, at 40 A the voltage on the fourth battery sagged about as much as on the third.


Internal resistance (impedance) is about 1 mΩ. It's a little lower for the first two and higher for the other two, which is probably why they sag more at 40 A.


Just out of curiosity, I'm planning to open a dispute. I've prepared photos for it, but I have a nagging feeling this may not go anywhere.
To be fair, I'd probably be satisfied with a 25% refund so I could buy another battery to replace the third one, because I really don't like it.
The thing is, LiFePO4 batteries have a very sharp voltage drop at the end of discharge. If one battery is noticeably weaker than the others, the protection board will trip before the UPS does—the UPS is what I plan to use this battery pack with. That could cause problems during operation.
Besides, I just don't like the increased voltage sag under load, but in that case it would probably be best to replace the fourth battery as well.

The third unit also has a higher self-discharge current. After sitting idle, batteries 1, 2, and 4 needed about 40–80 mAh to top them up, while the third took 220 mAh.


I regret that the other batteries weren't a good fit. They have good reviews, a capacity of 100 Ah, cost only twice as much, and use bolt terminals. If you're interested, here's the link.
Photo from one of the buyers



So, here are my conclusions.
As I mentioned, the capacity of all the batteries is more than 10% below the claimed figure, and the weakest one managed just 84.4%.
I could have put up with a lot of this, but I didn't like that the third unit also has more voltage sag, a higher self-discharge current, and, in my opinion, is generally more worn out than the other three.
I also have an issue with the nickel strips (if they are nickel): instead of proper wide strips, they used some tiny ones again.
And then there's the appearance: there are a few small dents, and the heat-shrink tubing doesn't fully cover the top of the case.

That's all for now. I hope this was useful. I'd like to ask: is it worth opening a dispute?