Again, let's look at the comment chain:

> A sensible 'normalised' comparison might be energy carried per displacement kilotonne or some such.

Defrost explicitly specified mass, "per displacemet kilotonne" To which you responded:

> Answering the original question, it's about 10-20x as much usable energy for the oil

10-20x is the ratio of energy density by volume, not mass.

I'm going to extend assumption of good faith, as it's easy to forget that there's two different measures of energy density. But yes, you did respond to someone asking about relative energy density by mass with the relative energy density by unit of volume. And the energy density by mass is indeed the limiting factor when shipping bulk lithium ion batteries, so this is a misleading (but probably not bad faith) figure to cite.