LiitoKala 21700 12s5p 20Ah Build

dayyummm
this is a pretty good find!

EDIT:
the cheapest ones I can find are $2.724usd per cell (in ‘bulk’ packs of 10)

Nice one @Accrobrandon.
I also wanted to build one for the longest time and as soon as @Agniusm tabs are ready, i will also build a battery with liitokala 21700. Btw the prices are continously going down, i watched them for about a year now.
If you want to test them. Use this https://www.aliexpress.com/item/ATORCH-150W-Constant-Current-Electronic-Load-200V20A-Battery-Tester-Discharge-Capacity-Tester-meter-12V24V48V-Lead-acid/32821877897.html?spm=2114.search0604.3.69.5603450a5bi03f&ws_ab_test=searchweb0_0,searchweb201602_2_10065_10068_10547_319_317_10548_10696_10084_453_10083_454_10618_10304_10307_10820_10821_537_10302_536_10843_10059_10884_10887_321_322_10103,searchweb201603_52,ppcSwitch_0&algo_expid=e21f1eba-2165-4bbb-9cd7-d7e5d897fdcb-13&algo_pvid=e21f1eba-2165-4bbb-9cd7-d7e5d897fdcb&transAbTest=ae803_5

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Fun fact: “Liito Kala” means “Gliding Fish” in Finnish. :finland:

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here some more pics from the build
this build i wanted to try something different… i usually solder a piece of 12ga across the series connects to help with the ampacity for each group… this made me ask WHY should I spot weld nickel across the series connections in the first place if its not enough (probably is but up for debate) for the spec’d current. For me the main answer would be “pack rigidity” keeping everything nice n tight and snug together but also makes it a real pain in the ass to service the pack should there be a group that dies or what ever… so i opted not to spot weld across the series… (except for these little things)

since I also am tight on space using a case meant for 18650s thin and flat were the goal.
I opted to try copper braid… cut some strips of nickel and solder up up direct so no heat transfers to the cell…
make sure you have plenty of solder as braid drinks that shit like juice… after they were all done the nickel legs could be trimmed to size before spot welding…

!

spot welded on and one side taped up all sexy like…


added bms wires to one side…could have made the 2 wires more length wise so they didnt cross but next time… after this first side was done I slipped on my new favorite, clear shrink wrap, over it to fish the pack-to-pack series wire through…

This go I wanted each pack to have its own extra sexy layer of wrap/insulation…

made sure everything was good and all lined up…i used a small strip of foam between each pack to prevent any rub through from side to side as well… then shrink wrapped the whole thing one last time in black wrap as clear was more expensive for the size i needed…

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Does anyone know if the charge discharge cycles have been tested? Like capacity after 500 cycles?

https://lygte-info.dk/review/batteries2012/LiitoKala%2021700%204000mAh%20Lii-40A%20(Yellow)%20UK.html

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Nice idea with the copper for the serial connections.
One thing to point out is, that all your current non the less will run over that small part of single nickle strip.

it´s just a very short piece, so probably it will not be an issue, but definitly a bottle neck there.
It also means that the current travels most from and to the cell which is attached to the one nickle strip for your serial connection. This can (does not need to) lead to get your p pack sooner out of balance as one cell is stressed more than the others.

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Watching this battery experiment eagerly…

that is something only big manufacturers offer sadly.

Hmm, but I think it can be done over a few days. Just charging and discharging and checking capacity in the process.

well can you realy take that data and project it for 500 cycles?

Got you beat, 10pcs @ 2.712 usd

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if its the same good on-ya =)

Im also half tempted to try the 30q’s even those the reports vary…most ive heard on those are sometimes there are dud cells… most have capacity and the real question amp output… in a large pack who cares kinda… but id hope at least for the 15amp on a 30q knock off =/

I was just eyeing those lol at that price someone needs to bite the bullet and take one for the team.

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haha step on up then…i already did my part =P

Hmm maybe I make a small order and see if I can send to mooch for testing.

10 pcs liitokala 30q 1.99 usd. That would be such a cheap pack.

150 shipped for 60… like… if the capacity and basic amps were there…id replace this 21700 and save a couple pounds lol… or i dunno what…i almost will have more batteries than boards hahaha

Just read the first review on the page. Said they got hot and voltage drop was drastic at 20a

Prob be good on a 6p single drive or something not pulling more then 10amp per cell. Or maybe a dual drive with 30a per vesc limit.

Off topic kinda…but is my thread lol… Impulse buy last night… 30q s be getting cheap… Was 3.45usd a cell after conversion… And guaranteed… Not sure what I’ll build, when and.for what board…