Puffed Lipo 20Ah 6S

I’m a bit afraid of my puffed green Multistar Lipos. I bought them one year ago from Hobbyking and I thought I trieded them quite gently. The cells never saw a voltage below 3.5v. I charged them about 50 times. In comparison you see the blue Turnigy Lipo (new)

What do you think? Is it a need to trash them? Does any body else have this problem?

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I was running those packs in my son’s electric trials bike for a couple of years. Same every time, the batteries puffed up after around six months. I went thru pack after pack always with the same result. Granted I live in a tropical climate and the bike pulls big Amps but so do our foils.

I was able to keep using them each time with diminishing returns but I don’t know as I’d be happy with that inside my board!

Ditch them and invest in an 18650 pack is my advice. Good luck.

Same with mine , 1 fire 1 swell /8 … Trash

Well I thinks it’s time to change to Li Ion. Do we have a good and cheap supplier in the EU for packs? I think I would go for 2x 6S10p without BMS.

I use the 16ah models, paralleled. You have to squeeze them before they swell and keep them squeezed. I use a frame made of glasfibre and nylon rods to clamp them gentle.

I learned this from my small electric vehicle where i use Thundersky Lithium, they never show the clamping frame in advertisement. Here is a picture:

Otherwise they end up like this one:

Round cells are wound so they cannot delaminate easily.

I use the Thunderskys with clamping frame since almost ten years now with little degradation only.

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I cannot recommand anyone in Europe for that kind of discharge , Homemade by someone , or nkon with nese module …

This thread is full of information.

For 30Q, @Jezza recommends https://www.fogstar-wholesale.co.uk/ over nkon and on 18650. I can’t find SAMSUNG 30Q 18650/3000mAh/20A on Rechargeable batteries - 18650 | NKON though. Keep us posted.

What might be worth for 30Q is not for 25R.
Quote for 200 x SAMSUNG 25R (Samsung INR18650-25R 2500mAh - 20A]) on each site:
Fogstar: 200x3.79GBP = 758GPB = 850 €
Nkon: 200 x 2.40€ = 480€ + 11€ shipping/15kg for EU.

My question: is the SAMSUNG 25R 20A cell suitable for our need ?

Guys, it doesn’t get much easier than this. Get yourself a spot welder (I use Kweld). A few meters of nickel strip and a hand full of 18650 lego bricks and voila!

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Went for the totally waterproof version this time. Concerns of overheating never materialized

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How many batteries in there ?

144 LGMJ1 3.5 amps/cell

Those prices for fogstar aren’t correct.
Fogstar wholesale are: £2.29 + vat.

Also nkon says €2.99 per cell for 200, how did you get a much lower price?

*Sorry I saw that was for the 25R

Beware that these 30Q 3000mah nkon batteries are for 15A discharge only whereas the Fogstar are 20A discharge: therefore my previous remark.

30Q 3000mah 20A disch at Fogstar = 2.26GBP/2.54€ : x200 = 452GBP/508€
200 x 30Q 3000mah 20A disch at nkon: not available

To anyone, at nkon, for 200pieces, SAMSUNG 3000mah 20A discharge
30Q: 2.54€/p and 25R: 2.40€/p
Are 30Q worth the extra 6% in price ?

The 20a/15a is just the shops rating them differently. They are the same batteries. Ultimately you don’t really want to push the 30q harder than 10a in order to get a better lifespan.

Seeing a bit of swelling here too. Trying to determine how puffed is too puffed and when to be worried with the normal natural decomposition. Took two photos of mine for reference.

Had the same one. One cell was from the beginning on damaged and then it puffed (exploaded) nothing terrible happened but I wouldn’t use yours for high current projects anymore.

Yeah. That’s what I’m afraid of and am holding off on using them until I know more. Going to check on cell resistance to get a better picture of what’s going on. Don’t want to mess with this much power going awry but it’s hard to dump $500 in batteries at the same time without being sure :wink: Better safe than sorry will be my default though.

I found that by increasing the cutoff voltage setting in the ESC my lipo’s don’t get as hot.
I don’t run my lipo’s below 3.6 volts per cell.
Of course this shortens the ride time, but your batteries will last longer.
I run my 18650 pack down to 3.2 volts per cell without issues. It’s well worth making your next battery purchase a 18650 pack.