The objective of the project is the development of a new Na/S battery technology for high power stationary applications. In contrast to the Japanese technical orientation towards energy storage plants for low-power load-levelling, which have now reached their technical maturity and are currently being commercialised, this project aims at modular high-power batteries for spinning reserve and standby applications such as for air conditioners, domestic and bureau appliances and other electric utilities. Related fields of application for this new type of high power battery are uninterrupted power supply systems and load-levelling in connection with decentralised, selfsufficient energy generation with renewable energies, e.g. solar energy. The conventional energy storage technology works with Pb-Acid- or Ni/Cd-batteries. Comparing the Na/S- and the advanced Pb-Acid- and Ni/Cd-battry technology, the paramount disadvantages of the latter are a much smaller energy density and power density, the requirement of constant supervision, control and maintenance by specially trained personnel, and the polluting partial recycling and removal respectively. In contrast the proposed modular stationary Na/S battery works maintenance free, is safe by design and friendly to the environment. The shortcoming in the technologies of the European manufacturers of Na/S-batteries for electric vehicle applications was mainly due to the single electrolyte-single cell concept. Under heavy duty operations this concept proved inadequate. The overall cell resistance due to the single cylindrical design of the ceramic electrolyte proved to be too high because of the restricted surface area of the ceramic electrolyte. High power demands, e.g. during vehicle acceleration, led to high current densities in the electrolytes and caused an increase in cell temperature well beyond specified limits. To address the high power demands of frequency control and standby applications, it is proposed to develop and demonstrate a new design of modular battery composed of a number of subassembly structures. In comparison to the single cell design an overall increase in power by a factor of 10-15 is possible.
Funding SchemeEAW - Exploratory awards