Tosoh Corporation began processing manganese in Japan in 1925. In 1932 the corporation began experimental production of synthetic manganese dioxide and 6 years later commenced normal production of EMD.
Following a forced stoppage of production due to World War II, the corporation resumed production of EMD in 1953, which since then has gradually replaced natural manganese dioxide, since it has been shown that its quality and purity improve battery performance.
Today, thanks to its experience, Tosoh Corporation has an average annual production rate of 60,000 tonnes, accounts for 20% of the global market and is a leader in the sector.