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My journey to lifepo4 world !

Acidcat

New Member
Joined
Jan 15, 2023
Messages
3
Location
Estonia
Hello !
Very new member here who started to seek into lifepo4 world. Previous experience with diy 18650 battery assemblys.
Anyways i decided energize my old truck|van with 24v solar system. Few solar panels and hybrid 24v inverter and decided to use lifepo4 cells on it.
Long story short just tought il go to aliexpress buy myselff lifepo4 cells from (trusted,goldmember what ever) supplier gifitt battery store.
I was aware i would get ripped off but hey started to start from somewhere atleast. Idea was even if i get riped off i could make 2 12v packs and sell them. Buy new 8 cells from new supplier and make good 24v battery.

after 2 months i recived my 8 cells.
Nominal Capacity:200Ah
Shell Material:plastic Shell
Nominal voltage:3.2V
Internal resistance:0.2~0.3mΩ
Max Continuous Discharge Current:200A(1C)
I myself tested internal resitance with all cells varied from 1.3 to 8.7mΩ and all of them were charged to 3.33v
I decided to top balance them all at 3.65v with 0.1amp cut off with zke tester. after individual cell charge i put them all in paralel and let them sit about a week.
After that i hooked them up in series to assembly 24v 200ah battery with daly bms.
Did my first discharge with 1,5kw load on inverter. Cells stayed balanced till 3.1v with 0.06 volt diff. Room temp was 21c and cell temps were the same troughout the test. In my calculations at 24v 200ah battery i should atleast get 4kwh out of it. But i only got 2.7kwh out of it. bms shut the battery down becoz 2 of my cells hit 2.5v mark. Others were at 3v. After test volt diff were 0.561v. After that i decided okay il try to charge it full with 10amp. Toke many hours till few cells hit the 3.65mark and others were around 3.2v still. I decided something is very wrong with cells and started individual cell test with zke ebca20 tester.

It results varied from 120ah to 150ah of theyr rated 200ah capacity.
Now the question. They supplier literaly telling me that those cells arent activated and i need to use them around 50 times till they magicaly gain 80ah lel.
Am i insane or this information is somewhat true.
Its kinda hard to belive if i buy ford truck with 3.0 engine on it and to get it better i have to drive 20 000km on it so it magicaly turns into 6l v8 lol .
Also if they say they tested it before it was sent out i assume its already activated and it couldnt lose half of its capacity during those 2 months of transportation.
I just wanna know do i realy have to waste my time and use those cells just to see to they magicaly gain 80ah back or i just should accept i got ripped of and just go full ham on refund.
 

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Let us know how that turns out.
It turned out well :)
Took another month for this dispute. Aliexpress stepped in and looked out for my proofs... They had 3 faults on product description what i proofed wrong with my test equipment. They gave me 2 options.. send them back and get full refund or keep them and get 50% refund of totall spent money.
I choosed second option so in totall i got actualyy 132ah cells 8 of them for 458 euros. I can just use them as test cells for hold them for random small projects or just make two 12v batterys out of them and sell them if i dont want then anymore.
 

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