From the February 2017 issue
How we store energy will be critical to the future of the electric car. While lithium-ion batteries are likely to remain the standard for at least the next decade, academic researchers and startup companies are racing to discover, design, and manufacture alternatives that will move beyond the limits of today?s chemistries. The following three technologies show the greatest potential:
Reduction-Oxidation Flow

In brief: Here, energy is stored in tanks as two liquid electrolytes rather than in the positive and negative electrodes. The electrolytes generate electricity as they?re pumped through the battery cells. Recharging can occur either onboard by reversing the process or by replacing the electrolyte at a fuel station. What might stop it: Many experts believe that achieving adequate range with a flow battery will require storage tanks too large to be practical in a vehicle.
Where it stands: NanoFlowcell, a company based in Liechtenstein, claims that it has a working flow-cell prototype vehicle that drove for 14 hours at city speeds with two 42-gallon tanks of electrolytes, although skepticism runs high in the scientific community. A startup founded by MIT researchers, 24M recently pivoted from reduction-oxidation flow batteries to what it calls semisolid lithium-ion batteries, specifically due to the packaging constraints of the large storage tanks.’
Solid-State Lithium-Ion

In brief: A solid ceramic electrolyte replaces the liquid elect...