Hacker News new | ask | show | jobs
by rrss 1708 days ago
what kind of batteries are meaningfully heavier when charged? are you just talking about like E/c^2?
2 comments
jermaustin1 1708 days ago
A water/gravity battery comes to mind. Definitely not the answer you are looking for, but an answer none the less.
link
enchiridion 1708 days ago
Depends on your definitions. Is the water pumped considered part of the battery before it’s elevated?
link
jermaustin1 1708 days ago
The pumping of the water would be "charging" the barrel of water, I guess.
link
einpoklum 1708 days ago
I'm sure this will work great for powering an aircraft, too. You could just let it all hang from an anchor at the highest point in the battery :-P
link
luma 1708 days ago
Gas tanks :D
link