Ditto. One of my on-going projects is converting an old trolley to electrically propelled - 10HP and parade-slow vehicle anyway. So I called up this battery outfit in Utah : how much for lithium-ion batteries. Oh, about $60,000 he said. eeeyeah, rrrright.
We have heard though about a company developing lead-foam plates vs flat plates : far greater surface areas for anode/cathode reactions, thus greater energy density. How are they coming along? Then there’s blacklightpower.com
I don’t know too much about ‘lead foam’ batteries but I would assume that being lead based would create the inevitable weight/efficiency problems.