sentences:  The design of "Hayabusa2" is based on the first "Hayabusa" spacecraft, with some matured improvements.It has a mass of with fuel, and electric power is generated by bilateral solar arrays with an efficiency of 2.6 kW at 1 AU, and 1.4 kW at 1.4 AU.The power is stored in eleven inline-mounted 13.2 Ah lithium ion batteries.