Power-wise, these warmers use a 18650 cell and a TP4056 charging ... of design requirements to quick but thorough explanations of nichrome wire and basic electronic theory. And then there ...

Laptop chargers are full of 18650s, and nichrome wire can be sourced from old toasters, hair dryers, or space heaters. You shouldn’t use just any old wire for this, though, or the battery will ...

Some metal cations have distinctive colours when held in a blue Bunsen burner flame. A nichrome wire is used to hold the test solid – nichrome has no flame colour of its own and it has a high ...