For this kind of vehicle, the cheap version could even use a low energy density sodium battery. I've posted several companies who are introducing new batteries or have them under test or pilot plant production there have been many. There are a couple of companies producing solid state batteries soon, having worked out the many problems and they promise improved energy density, in terms of mass and volume. Others will be using improved electrolytes with existing production facilities. Even NASA has made commercially viable breakthrough currently being exploited for electric aviation, if you look at some of the articles, I posted about the more practical research that is close to deployment, 5 years sounds about right and from there on improvements should increase at an even more rapid pace, 5 years is 2028. Batteries are gonna be needed for all aspects of green new technology from devices, to EVs, to home battery banks, to grid scale storage using flow batteries and the scientific, technology, financial, auto and utility communities are hard at work making the transformation happen.