Liitokala LiFePO4 batteries with a claimed capacity of 32 Ah

Not long ago, one of my readers got in touch and offered to let me test some batteries I hadn't handled before. But in this case, we're not talking about a different chemistry—that part is familiar enough—but about the form factor and capacity. As usual, though, it's best to read the review for all the details.


As you can tell from the title, today we're looking at LiFePO4 batteries with a claimed capacity of 32 Ah from the well-known repackager Liitokala.

I ordered four batteries at $20.3 each, so the total for all four was $81.2, with free shipping. They were packed very carefully. The large box in the photo on the left came from the person who sent them to me; the small one, as far as I can tell, was from the AliExpress seller, along with the individual protective packaging.


The batteries are covered in heat-shrink tubing, most likely applied by the repackager. When I was selecting photos for the review, I noticed that one of the batteries had its capacity printed on it. This was cell number 3 in my set.


The only information available was a table and a rough translation from the product page, which gave me the key parameters for the test:
Capacity - 32 Ah
Voltage - 3.2 V
Discharge current - 3-5C (or 96-160 A)
Charging current - 1C (32 A)
Charge termination voltage - 3.65 V
Charge termination current - 1.5 A
Discharge cutoff voltage - 2.5 V
Minimum voltage - 2 V
Weight - 631 g
Dimensions - 141 x 101 x 22 mm



Each battery has a Liitokala sticker, but I saw the exact same listing under the Varicore name. There, a set of 4 costs $76, and for some reason the claimed cycle life is 2,500 rather than 2,000.

The dimensions are more or less as specified. The only thing is that the listed length doesn't include the terminals, which add another 4-5 mm.
They're fairly heavy, at almost 600 g per cell, but that's 50 g less than the claimed 630 g.


Now for a particular detail: the terminals. These batteries have aluminum terminals, which are difficult to solder to, and drilling a hole and tapping it is risky. So the repackager (most likely) welded on wide nickel or nickel-plated strips. That would be fine, except the welds are poor in places. I managed to partially tear one off on at least one cell without applying any real force—just with my finger. The strips are sharp, which also makes it hard to get a good grip.


There's a second issue, too. In the seller's photo, the strips are clearly wider and would let you assemble a battery pack by soldering or welding them together. As you saw above, the strips are actually noticeably shorter.


And this isn't a typo: there's a separate photo on the page, even with a comment, so this is clearly a mistake. The strips in that photo are also welded on much more closely together and more frequently.


While measuring the internal resistance, I tried both methods: connecting directly to the terminals and connecting through the strips. The difference is small, but it's there.


The tests were carried out using an EBC-A40L tester, with a maximum charging/discharging current of 40 A.


Although the batteries had already been tested by the person who sent them to me, I still ran a conditioning cycle on each one: charge, discharge, then charge again at 16 A.
It was already clear at this stage that they weren't anywhere near 32 Ah, but I still used values based on C = 32 Ah for the rest of the tests. It didn't really matter, though.


During charging, I noticed that the batteries have a very short CV phase, so at 16 A the full charge took about 1 hour and 40 minutes. I set the cutoff current to 0.75 A, although given the sharp drop in current at the end of charging, I could have set it to the specified 1.5 A; the difference would have been insignificant.


At a charging current of 24 A, the battery can be charged in just over an hour.


After that came long, tedious tests. The conditioning cycle and plotting the graph for four discharge modes take about a day, so testing four cells takes four days.

The test was run at currents of 6.4, 16, 32, and 40 A. The graph labels these as 0.2, 0.5, 1C, and 40 A, based on the initially stated capacity of 32 Ah.

An interesting feature: all the cells delivered slightly more capacity at 40 A than at 32 A.
First


Second


Third
This battery was labeled with a capacity of 25.187 Ah.


Fourth


During the tests, I measured the temperature in two modes: at 32 A and 40 A. In the first case, I did pause a couple of times before taking a measurement, but I don't think a battery of this mass could have cooled down noticeably.
The temperature of the three test subjects stayed at the same level; only cell number three warmed up a little more than the others.
Judging by the temperature, I think they should be fine with sustained discharge currents of up to 50–60 A.


The cells also have some capacity imbalance. At 6.4 A, capacity ranged from 24.42 to 25.84 Ah; at 40 A, it ranged from 24.30 to 25.81 Ah. When cells are used in a battery pack, its capacity is determined by the weakest cell, so we can say the pack will have 24.3–24.4 Ah.


Speaking of battery packs, for easier assembly I'd probably recommend using cells with screw terminals. Sellers usually include busbars when you order several of them.


Since packs made from four cells like these are often used to replace lead-acid batteries, the obvious question is how their energy capacity compares to their volume.
Here's the answer: the difference is significant. For example, one of the LiFePO4 cells shown here has a capacity of about 78–80 Wh. A branded 9 Ah battery has roughly the same capacity (actually, even less); I once did a short review on this topic.
So a 4S pack made from the cells reviewed here won't be much larger, but it will deliver 24 Ah, or almost 320 Wh, at a discharge current of 30–40 A. Its operating voltage range will also be almost identical to that of a 12 V lead-acid battery.


And now for the conclusions.
On the plus side, the batteries handle loads well at discharge currents up to 40 A. The terminal voltage stays around 3.2 V, or 12.8–13.0 V for a 4S pack.
They can realistically handle sustained currents up to one and a half times that, or, I think, up to 80–100 A for short periods.

The downside is the large discrepancy between the actual and stated capacity: despite being rated at 32 Ah, the cells have a capacity of 24 Ah.
I also have some concerns about the spot-welded nickel strips. First, some of the welds aren't very good; at least one battery had an issue. Second, the strips could cause problems at high currents because they may heat up at the weld points.

And last but not least: the price. Compared with lead-acid batteries, each cell costs about as much as a decent 12 V 9 Ah battery, but offers comparable capacity and a longer expected service life. If I had to choose between lead-acid and LiFePO4, I'd choose the latter. The only drawback is that LiFePO4 batteries need a protection board, while lead-acid batteries don't.

That's all from me.