The NAS battery is an advanced secondary battery having a variety of attractive
features such as high energy density, high efficiency, long lifetime and so
on. TEPCO, in cooperation with NGK Insulators, has executed intensive R&D
activities including demonstration of megawatt class systems to realize cost
reduction and high reliability, leading to NAS battery commercialization in
April 2002. Its reliability and performance is highly appreciated as reflected
by its use for the FIFA World Cup 2002 held in Korea/Japan.