Given these ratios it sounds like it's more energy dense and less mass dense. That's impressive. Hope it is commercially viable.
In other words, I think "9 times more energy dense per gram" is probably far more laudable than "twice as energy dense per liter", especially in EV applications, where battery packs are significant weight, and weight reduces "efficiency" (obviously they are just as efficient, but it takes more energy to move the added weight. You know what I mean)