Energy storage materials: A perspective

Storage of electrical energy generated by variable and diffuse wind and solar energy at an acceptable cost would liberate modern society from its dependence for energy on the combustion of fossil fuels. This perspective attempts to project the extent to which electrochemical technologies can achieve this liberation. Realization of a reversible plating of a Lithium or Sodium anode through a solid Li+ or Na+ electrolyte would offer the best solution for a rechargeable battery that powers electric vehicles, thereby replacing the internal combustion engines that are creating a distributed emission of polluting gases from an increasing fleet of automobiles. Removal from the cathode to an external store of the product of the chemical reaction on discharge of a rechargeable battery can increase the capacity and lower the cost of stationary electrical energy storage in a battery. The ability to store electrical energy from wind and/or solar energy in rechargeable batteries at distributed sites can lower the cost and enhance the security of energy availability. The contributions from electrochemical capacitors and reversible fuel cells are also considered. (C) 2015 Elsevier B.V. All rights reserved.