Maybe of interest: Canadian startup making new and retrofit diesel electric trucks. Replace the diesel motor+transmission with a half-the-displacement diesel+generator, with electric motors as input to the differentials. The idea is you run for a while on batteries, when they get low the diesel fires up and runs at optimal load charging the batteries, then shuts down. There isn't anything wrong with the physics: IC motors are most efficient at full-ish loads.
Kind of a neat twist for logging trucks - the batteries drive the unloaded truck to the usually higher elevation logging site, load a big bunch of logs, then you use regenerative braking going downhill to charge the batteries. Vaguely like the pump-water-uphill as energy storage but with logs.
Also making a retrofit kit for smaller trucks, aimed at e.g. pipeline welders and other utility trucks.
https://www.edisonmotors.ca/
No idea if it will catch on, but a neat idea.