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200A discharge 3.7V 8AH flat pouch lithium ion cells

Awesome thanks!

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Still looking to buy 10 in Europe.

A 48S3P of these would be perfect as a main amperage pack for my EV, providing nearly 121kw of power which is above and beyond my requirements. I’m taking sugar daddy applications, I’m ready to provide my services

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same here.

A while back I considered doing a Miata conversion with these :smiley: Just don’t have the space for a project like that right now. What are you looking at building/converting?

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As I said earlier, I have a few laying around. Need about 8-9 euro each to recoup the shipping and import cost. If you really need them hit me up.

Alternatively talk amongs yourselves and order together. They took 5 months to arrive for me however…

What does everyone think about this method of connecting cells together? The SPIM08HP cell tabs are around 3" (76mm) long and around 0.5" (12mm) wide, with notches around 2" (50mm) apart for bolts /screws to pass through. I was thinking of cutting some 2" copper flashing into 1" wide strips, folding it in half like a taco, punching a couple bolt holes through, then sandwiching the cell tabs between the copper, and holding it all together with the screw clips. For side by side series connections, you could double or triple layer the copper taco strips to handle more current, but for stacked series connections or P-groups, the cell tabs would be sandwiched together, in full contact with each other, and the copper taco would just be keeping the tabs pressed together and not really carrying much of the current. Balance leads and mains should be easy to solder to the copper taco strips before bolting all together, and the p-groups and connections would all be wrapped with kapton tape or fish paper.

So, basically this general idea, (taken from the ES link below), but using the flashing and clips below. Thoughts?

IMG_0709

https://www.amazon.com/dp/B06XRYN8H3/?coliid=I3G27YTAX8KE26&colid=30QQ8PCANAU6E&psc=1&ref_=lv_ov_lig_dp_it

https://endless-sphere.com/forums/viewtopic.php?f=14&t=104415

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Not so much of a feedback to your design but I simply used only two rivets and washers per tab for my battery and it seems to be good enough (any extra effort for better connection is of course a plus).

When I pull 100A I have seen 2V maximum voltage drop in my pack. In average this is 0,28v drop per cell.

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I have had some issues with single cells dying much faster than the rest. After like 3.5V one cell will just drop below 2V sometimes extremely quickly. I’m not sure what I did to it because I have done sooo much.

here I’ll go for a ride and stop frequently and take some pics of the cell voltages.

I guess I’ll have to take this pack apart to maybe remove the bad cells.

I suppose this would be a good scenario for a Smart BMS. I just built two 6s packs for a 12s build that I’m working on out of these (using rivets + manual crimps). Havent had a chance to test these at 12s (I’ve had these on a 10s FlipSky but meh) on my new DWII, but hopeful that I can later today.

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I got the bad cell out it’s totally puffed and reading like .8V

replaced with a cell semi-carefully brought to the same ish voltage as the rest, and it’s on the charger now.

@Arzamenable these foil crimps are fucking great! I can take bad cells out with just a flathead screwdriver takes very little effort, and then reuse them as they seem to hold fine after being rebendt.

Will report back any issues.

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Which foul crimps work the best for you?

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And with a nice “clip tool” : https://www.aliexpress.com/item/4001171983939.html?spm=a2g0s.8937460.0.0.68472e0eqdbOf4

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Have looked a couple times and none of them really seem to be the perfect size. I got the ones that @Arzamenable posted when I asked him I ended up having to cut the first tooth off of them.

What I liked is it they were one of the cheapest options and had high current ability.

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Let’s see what made this 6S pack loose all power when I hit the throttle uphill.

Oh just a bad solder joint.

These cells still great

I’ve been wanting to build a spot welder out of these packs.

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me too but hobbyking is taking 3 weeks to deliver smh

hoping 3S3P works good.

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3s3p works great.
I made series connections with some bent aluminum and rivets. the main leads are 2x 10awg to a (gulp) single xt90. Kweld probes get too hot to handle before there’s any heat from the batt

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yes the thermal performance on these cells is great. They only heat up when I really beat on them while they are completely encased in foam in a case on a hot day.

My only slight worry is the 3.5mm bullets I was planning on using for paralleling 3S1P’s, but x3 shooouulld be ok.

Can always step em up later