These are flow batteries. The limitation is the limited solubility of the charged ions in the carrying fluid. The charged fluid is pumped in - discharged - and

These are flow batteries. The limitation is the limited solubility of the charged ions in the carrying fluid. The charged fluid is pumped in - discharged - and then pumped out. Well suited to stationary systems where huge tanks on the land are used. You could do it now with 2 50 gallon tanks. Fill tank 1 with charged fluid and discharge it into tank 2. AFter 80-100 miles, stop and pump new fluid into tank1 and put the discharged fluid into the roadside charge station. https://en.wikipedia.org/wiki/Flow_battery https://en.wikipedia.org/wiki/Flow_battery