French researchers have announced a prototype of an 18650 sodium-ion battery. If you’ve bought a powerful LED flashlight, a rechargeable battery pack, or a–ahem–stronger than usual LASER ...

So [Travis] decided to upgrade it to make use of the ever-so-common, 18650 lithium-ion battery. Not looking to ... a few strips of cardboard from a case of beer — again, this is just making ...