Combustion engines are quite inefficient and so are fuel synthesis processes. batteries have a high energy round-trip efficiency. The energy density does not ma

Combustion engines are quite inefficient and so are fuel synthesis processes. batteries have a high energy round-trip efficiency. The energy density does not matter as much in cars, which after mobile compute have been the primary drivers for technology. The density may make more sense for planes. Additionally 1st gen biofuels have poisoned the well to some extent due to competing with food crops.