Measuring 18650 cell capacity

[awol]

So I've lots of these cells out of my old ebike battery to check and match up. The routine I've come up with is
1 - charge up to 4.2v and leave a day or so to settle and check they are still around 41.5-42.0v
2 - discharge to 3.0v@1a and take a mah reading on my imaxb6 for reference
3 - charge back to 4.2v@1a and take another reference reading
4 - discharge back to 3.0v@1a and use this discharge reading.(asuming the 3 readings are similar)
Does this sound reasonable, or is there a simpler method?

 

[soundwave]

just charge and discharge will give you the capacity off the cells you only get out off them what you can put in

cheap diy charger

 

[Deleted member 4366]

http://www.ebay.co.uk/itm/282308947924?_trksid=p2057872.m2749.l2649&ssPageName=STRK:MEBIDX:IT

 

[awol]

http://www.ebay.co.uk/itm/282308947924?_trksid=p2057872.m2749.l2649&ssPageName=STRK:MEBIDX:IT

That unit looks good, testing 4 cells at a time will certainly speed things up.

 

[Deleted member 4366]

I ordered one about a week ago to see how it performs.

 

[awol]

I ordered one about a week ago to see how it performs.

Please come back with a review, I notice it says default discharge current of 500ma but am wondering if it can discharge all 4 cells at 1amp each at the same time.

 

[soundwave]

looks like it can only do 1 lion cell at a time. any more and it will prob start to melt lol.

8. Discharge current range ( mA ):200, 300, 500, 700, 1000 ( li-ion cell battery only )

 

[awol]

Got a good tip off the guy in this video to charge the cells up to 4.2v and leave for a couple of weeks to allow the weak ones to show themselves up.
Works too, I've waited a week and I have a variation of
4.09v 4.16v 4.18v 4.2v (yes 4.2v=no loss!!)
Can't wait to see the capacity difference between the 4.09 and 4.2v cells.

 

[soundwave]

you been watching my liked videos lol he works with ev west