This page is read only. You can view the source, but not change it. Ask your administrator if you think this is wrong. **18650** is a popular battery type that is a cylinder of 18mm diameter by 65mm long (hence the name with the added 0 on the end to state it’s cylindrical format). It’s usual chemistry is lithium based and it's usual operating voltage range is between 3.7v and 4.2v. They are mostly found in battery packs for laptops, ebikes, backup packs, UPS and even some EVs. Many technical people recycle single 16850 cells from these sources although single cells are also used in vaping devices and poundshop backup battery units. Individual cells can have a capacity from around 1800mah to 3600mah, what is printed on the battery may be optimistic especially on the cheaper cells. Brands like Samsung and Panasonic have good reputations however that leave them open to counterfeiting. There are lots of brands like UltraFire that are not seen as reliable. {{tag>[Batteries]}}