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Basic 100Ah LiFePO4 build from LiitoKala Power cells for camper

3d0g

New Member
Joined
Feb 18, 2021
Messages
26
Location
Elizabeth, CO
Hi, first post here. Thought y'all would like another data point on the LiitoKala Power cells from AliExpress.

I needed a budget-friendly power source for my new teardrop camper build and with the price of LiFePO4 cells coming down so much, I figured I'd give it a shot. Ordered the 4 pcs 100Ah pack from the LiitoKala "official" store on new-years eve and they arrived in Colorado 48 days later. Box was well taped and undamaged. Inside, the individual cells were thoroughly wrapped in closed-cell foam wrap. I've got enough of that stuff to last me a lifetime now! ?

Anyway, the package arrived during that artic blast that hit the US and my IR temp probe said the cells were at -2C, so I left them on the bench for the day to warm up. Next morning I gave the cells a closer inspection. All are damage-free, have identical markings and dates, and the threads on the terminals are well-tapped and clean. LiitoKala includes the usual zinc-coated copper bus bars, screws and washers. No surprises there. I had also picked up one of the DALY "budget" 40A BMSes off eBay for $18. I knew it didn't have low-temp protection but my charge controller - a West Mountain Epic PWRgate - does so I already had that covered. Out of the box, the individual cell voltages varied from 3 to 3.3V. I wired it all up in standard series config and connected to the bench supply at 14.2V to bulk charge and then I'd parallel to finish up with a top balance.

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Next morning I had a look and to my surprise, all the cells were within 5mV of 3.550. Guess the DALY balancing works OK! I decided to forego the top balance for now and proceeded to build out the pack. I couldn't find a manufactured case at a price I liked and I had plenty of scrap ply around so I built my own. The included bus bars worked best with about 3mm separation between the cells so I cut up some scrap acrylic on the laser cutter for spacers. Did have to make a hardware store run for 8" bolts to keep the pack under compression.

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Assembly was uneventful. While the DALY BMS appeared to perform well on the bench, I decided to add some jumpers so I could monitor individual cell voltages w/o disassembling the pack. Used a little Loctite on the screws for good measure.

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All assembled, it was off to the trailer for some performance testing. Now I don't have all the fancy test gear y'all have so this must be taken with a grain of salt. The Epic PWRgate does provide live status of supply / battery voltages and active current flows via USB serial and I'd also put a shunt / battery meter in the trailer so I'd have two independent sources of energy in and out of the pack. First order of business was a full charge. Now I'm not interested in eeking out every last μA so my charge parameters are pretty conservative with the max charge voltage set to 14.5V, recharge voltage at 12.6V and charge current set at 10A. I let the Epic PWRgate do its thing.

I went to check on the charge status before turning in for the night and the PWRgate said the charge was complete. The battery meter and PWRgate were in total agreement with the total amperage shoved into the pack so that was encouraging. Temps were approaching 0C so I pulled the pack and brought it inside. Testing the individual cells, they were all within 20mV and the pack was at 13.7V. Next morning, all cells were within 5mV.

A new day and a charged pack, it was time to see if I'd got my money's worth from LiitoKala. This would be decidedly low-tech - I hooked up my 300W inverter, plugged in two 60W shop lights, and started the timer. Trailer battery meter said the draw was 10.8A. It was a cold day - ambient temp in the garage was 4C. This would be the one instance where I'd trust the BMS as I let things run until it tripped out. I wasn't around when it happened but according to the logged data from the PWRgate, it was at 560 minutes. Some napkin math... 560/60*10.8 = 100.8 total amps over the run. We have a winner! By the time I'd checked the cells, they had recovered a bit but they were all within 50mV of 2.3V.

Granted, this is just one fairly un-scientific test but I'm thinking LiitoKala Power did me a solid. Under $200 all-in for 100Ah of power? I'm happy. I'll wrap with a couple trailer electrical porn pics. If you haven't guessed, I'm a ham which is why there's Anderson powerpoles everywhere. I'll be able to run my radios in style come Field Day this year!

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Thanks for the good review and your build pictures. The more reviews we can get, people can know which sellers to trust.

I see you are using screws instead of studs and nuts ..... did you see any problem with the threads not being perfectly vertical?
 
I see you are using screws instead of studs and nuts ..... did you see any problem with the threads not being perfectly vertical?
Negative. The threads were clean and well cut. I used the screws LiitoKala had tossed in and they worked just fine. I did double-check them with a caliper to make sure they wouldn't bottom out. Hand-tightened with a large #2 Phillips with a dab of Loctite for good measure.
 
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