alrighty got through all 200 with preliminary tests
3 cells low voltage
11 cells questionable weight 46-48g
33 cells 3.7-3.76v
143 cells 44-45g 3.66-3.68v
I’ll be running the 3 low V and 11 with questionable weight through charge/discharge tests
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Not these cells but are cells which are sent at 3.8v ok?
Thank you
theoretically yes 3.8v is fine
but that is higher than typical storage voltage
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What do you plan on using for the charge-discharge test? Do you have a rig for it or is it a spefici tool?
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I’ve got a dozen foxnovo 4 cell chargers/cap testers from my salvaged 18650 powerwall days.
I’m gonna do 2 charge/discharge cycles on that @ 1A
I also have an evpeak 4x6S 400watt charger that I can do higher discharge current on
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unwrapped the 3 low V cells, one is showing some rust
rusty one is lowest 2.93v
@Guy746 any thoughts on this?
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Oh snap! It’s on and poppin now! Don’t know exactly how I’m gonna use all this stuff, but one or two front wheels will be for my drift trike(s) and I guess the rear ones will send me down the mid drive e-bike rabbit hole in the future. The SPIM08 cells will probably end up being used partly for an eATsk8 battery and partly for a backup battery to run my fridge or freezer for a couple days when we have our now annual red flag fire warning blackouts. Any info on how best to connect and configure those SPIM08 cells would be appreciated. Thanks @Guy746 for the special wheel deal and for making all of these battery options available to us! 
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can anyone who received the e-bike hubs confirm the hub holes of the hub motors (I think 36 spoke) and the drop out spacing? I’ve read that the sturmey archer is 135mm thru the drop outs… but ya know…
why?
because fat tire bike…
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I don’t think they are shipping until monday at least
Fat tire bikes have different axles yes
example
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https://www.bafang-e.com/oem-area/components/component/motor/fm-g020250350d/
@b264 would appreciate that last one
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definitely 
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Bonus points for someone who figures out how to DIY a Rungu style bike front end with two BAFANG hubs.
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Skateboard pusher trailer… using a BAFANG pedal sensor hack… so as the board wheels speed up the motor hub power ramps up.
To many ideas… floating out there.
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hey @Guy746 been testing my batch of 200 30q, 3 were lower voltage than the rest, I’ve unwrapped several and found rust around the positive terminal
I’ve also been finding cells with dings in them, this is one of the worst
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Hey Scepterr… no worries, just send a message in and the guys will work with you on it.
Keep in mind… your not dealing with NASA spec batteries when your ordering lots of 200 at ~25% the normal retail value. ( I am just guessing at the 25% by the way. ) Even with batteries new in boxes, you might find some that where returned back into someones inventory before it got to us. The batteries that are new in original boxes are often the ones that have been sitting in the warehouse somewhere the longest.
With that long on a shelf, seeing only 3 with lower voltages out of 200 is pretty solid. If the cells had issues, you would see a very significant voltage drop after all that time.
A voltage drop test is generally where you charge all the cells up to the top and let them sit for a week and retest. That’s the first step in weeding out your bad cells. Then you want to run them through a capacity test. The capacity test numbers will be what helps you dial in the best to the worst.
I would charge up several of them up including the 3 you are concerned about and then set them aside for a while… Check their voltage from time to time. Bad cells will also feel warm to the touch while charging or immediately after charging… If they are smoking with flames shooting out the ends, that’s also a sign something might be up with them.
When your building large battery packs… you always want to start with more cells then you really need. You will weed out the bottom percent as you go. One thing you get with $4 and $5 cells is that someone ( in an ideal world ) has done all those steps. They buy cells wholesale market at .50 to 1.50 each, test them and then sell them them for $3 to $5 each.
Rust… If your not seeing it on a lot of others, I wouldn’t stress about it too much. The caps do not look scuffed so they don’t appear to be recycled sold as new. Dent’s… not something anyone has mentioned before over the years, but most of us are not taking the wrappers off. It is in a section that gets crimped down during the manufacturing process.
anyways… just reach out to the support team and they can work with you.
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Lol I like you guy
Interesting info, thanks!
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Really good to see that you guys clearly know what you’re talking about. I really hope to see more deals in the future targeted towards us as you’ll many of the people here will happily drop hundreds instantly on a good deal (I would if I could get shipping…). This is a really great option for everyone, good to see some competition
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This is the place to find the info. Quite a few people have built with these now and there is a variety of way to connect them
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I am thinking about having my order shipped to a freight forwarder in California as soon as I have spare cash and there is a good deal.
So far I found out that the only way I would get bare cells shipped here is by sea. What’s fucked up is that it is not cheaper than by air, go figure.
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Oh shit my understanding was that it would be WAY cheaper. My issue is that all the forwarders require you to set up a business account with them to ship by sea, or they simply won’t ship batteries. Not sure if it’s worth bothering at this point
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