batteryuniversity.com

yQrNv TIL that body fat has the exact same net calorific value (energy by volume) as gasoline, 9700 calories per liter.
N7rE6 TIL that 90% of "dead" cell phone batteries returned to the manufacturer are repaired and resold.
5Y7nn TIL it's a myth that you should fully discharge your cell phone/laptop batteries before charging - it's a holdover from the Ni-Cad chemistry era and its "memory effect", but lithium-ion batteries are at their healthiest when you use very little and charge very often