# What setting for a dischargerr to measuring capacity

#### N4aeq

##### Newly Enlightened
I have a ton of 18650s hulled and cleaned up from old laptop packs, normally charge them at (1a @ 3.7v) setting which ends up around 4.18v. Now I would like
to measure capacity in ma, I set my charger to discharge at (1a @ 3v) voltage is 3v default, the final reading is in total minutes not ma, so what would
be the proper math to give a cell capacity reading in ma?

#### ChrisGarrett

##### Flashlight Enthusiast
I have a ton of 18650s hulled and cleaned up from old laptop packs, normally charge them at (1a @ 3.7v) setting which ends up around 4.18v. Now I would like
to measure capacity in ma, I set my charger to discharge at (1a @ 3v) voltage is 3v default, the final reading is in total minutes not ma, so what would
be the proper math to give a cell capacity reading in ma?

1A draw at 180 minutes would be 3 hours, so 3Ah, or 3000mAh?

I'm an English Lit. and Comm. major, so be careful.

Chris

#### hiuintahs

##### Flashlight Enthusiast
........... Now I would like to measure capacity in ma, I set my charger to discharge at (1a @ 3v) voltage is 3v default, the final reading is in total minutes not ma, so what would be the proper math to give a cell capacity reading in ma?
Capacity of a cell is current x time. So what you really want is mAh (mili-amp-hours). The Panasonic NCR18650B is a 3400mAh battery (or 3.4Ah) which means if you discharge at a 1 amp rate you can get it to do that for 3.4 hours. So I'm assuming you discharged your battery at a 1 amp rate until it hit 3v?..........how long did that take?

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#### N4aeq

##### Newly Enlightened
Yep, I re read the manual and found the readout in the charging window that shows (minutes) changes to MA when in the discharge mode, so
as usual I should have read the manual