Question Lots of 18650s

[Fruity_Grebbles]

I have a bunch of 18650s from various sources. Is there a method I should use to test their health before I use them together? Any rules about matching capacity?

Also, is there a BMS (like the ebay "red battery boards") that would be suited to using many cells together?

I'm not really sure what to look for. Thanks for any help.

 

[cheese]

Jehu has some videos on this subject. He's got pretty good advice, but he does have some strong opinions about battery safety that you may want to take with a grain of salt. As for battery boards, anything that we use with brand new 18650s can be applied to used ones, just try to keep the batteries relatively similar in capacity together.