Hydrogen vs. Battery Electric Cars

I saw someplace where there is I think Toyota one of the car manufacturers in Japan may be experimenting with hydrogen as fuel for a internal combustion engine Also I saw where JCB equipment company is experimenting also with powering the equipment with hydrogen and also using internal combustion engines supposedly the emissions  are much better and supposedly the only omissions are some CO2 because of the oil film in the engine cylinders and just water vapor compared to gasoline it’s much cleaner and most engines can run on it But theProblem is PreDetonation of the hydrogen In the cylinder of the engine supposedly they’ve gotten around that problem somehow JCB has .There’s a video on YouTube of it someplace