Shenzhen PowerOak Newener Co. Ltd is a subsidiary of Kayo Maxtar Battery Ltd, who was into lithium ion battery field by deep cooperation with Japanese team since 1999. The technical experience accumulation of manufacturing li-ion battery and BMS Battery Management System( lays a solid foundation for PowerOak all-in-one solar energy storage system ESS(.br monitor your solar production anywhere anytime. PowerOak makes you enjoy solar green energy and uninterrupted power supply and never worry about power outage.