> The only valid battery capacity unit of measure is watt hours.
I would also accept Joules. But yes, the unit should be a unit of energy.
I would also accept Joules. But yes, the unit should be a unit of energy.
1 joule is 1 watt-second to be precise. So 1Wh is 3600 joules.
Also, I wonder how usable a unit of time that was not based on a day would be, since so much of our life revolves around that cycle.
Compare Mean solar day vs Stellar day vs Sideral day - the difference is less than 5 minutes or so.
https://en.wikipedia.org/wiki/Solar_time
I was thinking along the lines of the ancient Sumerians arbitrarily deciding to divide 1 day into 24 hours, and 24 hours into 60 minutes, and 60 minutes into 60 seconds, and how that doesn't have anything to do with how humans came up with the concept of 1 year (the Earth rotating around the sun).
(Context: 1 Calorie = 1 kilocalorie = 1000 (gram) calories; https://en.wikipedia.org/wiki/Calorie)
The "(gram)" make no sense here. We commonly use "kilo" as shorthand for kilogram", but kilo is just a prefix indicating 1000 and never indicates "kilogram" when given as a prefix to another unit, and so there's no implied/left out "gram" in 1 kilocalorie.
Though as the difference is at most 0.5%, it's probably won't affect your battery buying experience. :)
Measuring by TNT equivalent is more standardized. "This battery stores 50 grams of TNT."
Ummm, on second thought, maybe don't use that term at the airport, .. or in secure areas, ... or near the police, ... or in public, ... or on social media or anything else tapped by the NSA or other authorities.
Another fun one would be milli hundredweight leauge (mcwt·lg). Both hundredweight and league have multiple accepted definitions to make it more "fun". But the range maps quite nicely to everyday things:
AA battery - Around 5 mcwt·lg
Phone battery - Around 20 mcwt·lg
Laptop battery - Around 200 mcwt·lg
Car 12v battery - Around 1,000 mcwt·lg
EV battery - Around 100,000 mcwt·lg