Mitsubishi Heavy Industries, Ltd., (MHI), has developed what it says is Japan’s first cargo container-type large-capacity energy storage system that uses a lithium-ion rechargeable battery. The system is capable of providing power of up to 1MW, and its mobility makes the system suitable for a wide range of applications, including emergency use. The actual system has been installed at the Nagasaki Shipyard & Machinery Works of MHI in Nagasaki Prefecture, Japan, to begin verification testing for a power stabilization system application from early July towards the commercialization of the system.
The container-type "megawatt-class large-capacity energy storage system (ESS)" consists of a 40ft-long container unit, which houses more than 2,000 units of lithium-ion rechargeable batteries, and a 20ft-long container unit, in which two power conditioners are installed. Power conditioners are used for dc-ac conversion and their input/output control. Each container unit can be moved by container trailers. The system has the capacity to store 408kWh (kilowatt hour) of power and is designed to have a system efficiency of 90%.