You can check out the ZKETech electronic loads for discharging battery (up to the unit’s ratings) but you’ll need a LIFePO4-capable charger. I do not have one to recommend.
There is no way to test a cell in zero seconds. 
The standard is 0.2C discharge for capacity testing. That is five hours for any cell (after fully charging it).
Multiple cells at the same time? You won’t be able to do that unless there is a round cell charger out there that can discharge test LiFePO4 cells and you modify the contacts to connect to pouch cells.
I don’t understand this part, the lifepo4 cells are not pouch cells.
5 hours? Ok that’s out, it would take a month non stop to test all the cells.
So the best plan I can tell is voltage test and charge all the cells, let them rest and voltage test again, build the pack and if there seems to be any issues then disassemble and use the test machine?
EBD-M05 Mini Electronic Load Battery Capacity Power Tester 19.5V 5A 30W https://www.amazon.com/dp/B07G9VKN1T/ref=cm_sw_r_cp_api_glt_fabc_H0TCVCVFMK5DGXHR1KBC
Does what I need?
Ahh…my mistake then. They’re round cells? I thought you were referring to large pouch cells.
That would be a lot of grief.
What do you want to accomplish with your testing? Comparing performance or just looking for crap cells?
If the latter then you could use that 5A electronic load at 5A and do discharge testing faster. Charge all the cells fully, let them sit for a day to settle, measure their voltage, let them sit for at least a week, remeasure their voltage to check for leakers, and then 5A discharge test each one.
Yes just want to weed out crap cells.
Thank you.
12s7p p42a pack for the new flux build
Anyone got news on the cell shortage? 18650 battery was supposed to have p26as in stock
yeah https://www.fogstar-wholesale.co.uk has some P26A and P42A in stock at the moment. shipping to North America might not be worth it tho 
It’s barely started, will get worse, and will last for a verrrrry long time.
We have to wait until new production lines are finished, all the big customers finally have their orders filled, demand drops off, excess cell inventory builds up at customer sites, the customers sell off these excess cells, the distributors/resellers buy them up, and then these resellers sell them to the vendors who will sell to us.
This will take a while.
Yikes… Grim news for this lil community. Maybe $7 a cell for 40t isn’t that bad after all…
We all knew we shoulda bought more.
What’s with this warning? what happened?
Samsung decided not to sell their cells for vaping purposes because too many “my diy vape blew my face off and its Samsungs fault” cases I guess
Samsung and LG Chem have been very active in trying to prevent the sale of their cells to end users.
No li-ion cell is ever supposed to be used outside of a fully protected battery pack but some companies go after unauthorized sales (any sales not to pack assemblers) more actively than other companies.
Regarding that mention of switching to Sony cells. Sony hasn’t made round li-ion cells in years. Murata bought Sony’s factories in 2017 and makes the VTC cells now (they are the same).
a lot of people still haven’t caught up to that news yet, still calling cells Sony VTC [X] 
What are the current thoughts on the Molicel 20700A and the Sanyo 20700A? Are they worth while (over the P42a since it doesn’t seem like they are in stock anywhere and won’t be for a while)?
nkon hast molicell P42A stock. At a pretty good price too.
Those are the last cells from the most recent shipment, price isnt good at all since I got 300+ for 4 euro a cell.
