On 2013-01-02, Orval Fairbairn wrote:
The 15:1 ratio is working fluid, including oxidizer. With a battery, you
have to carry the whole mass with you.

Comparing what a battery needs to contain with "working fluid" is still
just not valid. To make a comparison between what a battery must store
vs fuel and oxidiser, only the fuel and oxidiser and the number of joules
you get out should be considered. You don't have to carry the "working
fluid" equivalent in a battery, only the equivalent energy, in other
words the equivalent of fuel+oxidiser.

The "active ingredients" that should be compared are just the oxidiser
and the fuel, not the nitrogen. An electric motor doesn't need it,
it only needs joules of electrical energy.