On Friday, April 26, 2019 at 6:04:59 PM UTC+1, Commander Kinsey wrote:
Why do most lithium batteries have a flat +ve end? This means they don't make contact in some devices, and tin foil is required!

I think you mean Aluminium foil or Aloooominum as the continentally challenged say.
How many people keep Tin foil in their house and why would they?