Sodium/sulfur batteries electrochemical system

R. S. Gordon, W. Fischer, A, V, Virkar, in Ceramic Transactions Vol. 65, Role of Ceramics in Advanced Electrochemical Systems, P. N. Kumpta, G. S. Roher, U. Balachadran, eds., American Ceramic Society, Westerville, OH, 1996, pp. 203-237. Current review on the application of ceramics in the sodium sulfur battery and the solid oxide fuel cell. 

Once the principles of operating in a molten salt environment have been grasped, suitable extrapolations or interpolations of materials requirements and cell and equipment designs can be made between different systems. In bringing a molten salt process into commercial operation, unique materials problems requiring special solutions often limit its progress, but practically never prevent it. Thus, if a desired result may not be achieved for theoretical reasons in any alternative electrolyte, because of electrochemical instability, for example, then initial development costs and difficulties become inconsequential. Such has been the case with thermal batteries, " sodium-sulfur batteries, molten fluoride nuclear reactors, and molten carbonate fuel... 

However, the issue of the stability of power supply grids is not a new one. Electrochemical systems for energy accmnulation have been installed on the grid for over 20 years, with lead-acid or nickel-cadmimn batteries. More recently, we are witnessing a significant development of sodium-sulfur batteries (which are discussed in detail in Chapter 12). Experiments have been performed with redox flow systems (also detailed in Chapter 12). The unitary powers range from several MW to several tens of MW, and the quantities of energy stored from several MWh to tens of MWh. 

Development of lithium ion batteries proved to be a power factor of technical advance. While at present such batteries form the base for portable electronics, in the near future, one could look forward to wide application of larger devices based on lithium ion batteries, including their application in electric transport and smart grids. However, many researchers at present have already started attempting to predict the further development of batteries that fundamentally differ from lithium ion batteries. One can identify three electrochemical systems against various possible new battery variants (i) lithium-air batteries, (ii) lithium-sulfur batteries, and (iii) sodium ion batteries. 

To transport people and material growing transportation systems are needed. More and more of the energy for these systems is drawn from secondary batteries. The reason for this trend is economic, but there is also an environmental need for a future chance for electric traction. The actual development of electrochemical storage systems with components like sodium-sulfur, sodium-nickel chloride, nickel-metal hydride, zinc-bromine, zinc-air, and others, mainly intended for electric road vehicles, make the classical lead-acid traction batteries look old-fashioned and outdated. Lead-acid, this more than 150-year-old system, is currently the reliable and economic power source for electric traction. 

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