18650 pulls at 2.2V - safe to charge?

[Halo]

Above 2.0v is still ok to recharge. Below 2.0v should be trashed.

How far can LiIon be discharged?

How far can LiIon be discharged? [image] I do often see a question about how far LiIon can be discharged and if it is safe to charge a discharged LiIon. These questions can be fairly difficult to answer precisely, LiIon manufactures do not publish much about it and LiIon is not just LiIon, there are many different chemistries with similar but not equal specifications. How to measure the discharge cut-off voltage? Some people do not wish to discharge below 3.6 volt (or s…