Sodium-Sulfur Batteries

Abstract

The sodium-sulfur battery is one of the high energy electrochemical devices being developed to store energy. These batteries satisfy the specific energy requirements for both automotive and utility load-leveling applications. Sodium--sulfur cells which use fi-alumina cell dividers have unique properties other than high specific energy, and work is being carried out by many organizations to develop practical battery systems.A growing awareness of the energy requirements of a technologically advanced society coupled to a deepening understanding of the environmental implications of that technology has renewed interest in electrochemical energy storage devices. This interest has manifested itself in a growing effort to develop high energy battery systems for energy storage. These devices will probably be used mainly as batteries for electric vehicles and as load-leveling storage systems for electric utilities.The specific requirements of these two applications differ in several respects, but generally both require long-lifetime, high specific energy batteries which operate in a nonpolluting manner. Specific energy is a prime requirement for vehicular traction applications whether in small urban vehicles or electric railways. A workable goal for this application is a battery which provides a specific energy of 150-200 W-hr/kg. Load leveling-the storage of electrical energy generated during off-peak hours to be used during peak consumption periods-does not impose as stringent a weight requirement. Nonetheless the battery installation must be as compact as possible so that the batteries may be sited at the sub-station, thereby greatly reducing transmission costs. Several electrochemical systems are being developed to meet this requirement.The selection of systems which might be suitable for high specific energy batteries begins with the consideration of chemical periodicity. These purely thermodynamic considerations must of course also be tempered by the limitations of kinetics as well as by the various require-216 Downloaded by EMORY UNIV on August 24, 2015 |

Research Progress toward Room Temperature Sodium Sulfur Batteries: A Review

“…The high content, low cost and ability to provide high voltage make sodium an ideal choice for the anode materials of high-energy secondary batteries [ 6 ]. Sulfur has the advantages of strong oxidizing property, mature treatment technology, low cost, ready use [ 7 ], no toxicity and high capacity (when each atom transfers two electrons [ 8 ], the capacity of sulfur is 1.675 mAh g −1 ) [ 9 ], etc. Sulfur has an attractive advantage over lithium as a battery cathode.…”