It also doesn’t mean that the materials they found will work outside laboratory conditions. They may very well have found materials that will form a battery with the same work efficiency as gasoline, 12,000 watts per gallon. However, it might cost $150,000/battery to create.
“12,000 watts per gallon.”
We know that the author of the above failed 9th grade science!
You want either BTUs or kilowatt hours. 1 kilowatt hour is equal to 3,412 BTUs.
There are approximately 125,000 BTUs in a gallon of gasoline.
You could also use joules, but that unit is not commonly used for the purposes of expressing electricity use (after all, your electric bill is in kilowatt hours, not joules).