The Transport Ministry said members of the team working on the investigation would leave Tokyo on Sunday for Everett. It provided no further details.
The U.S. Federal Aviation Administration and Boeing earlier dispatched investigators to join the probe in Japan.
All 50 Boeing 787s in use were grounded after a lithium-ion battery in a 787 flight by All Nippon Airways on Jan. 16 overheated, forcing an emergency landing. Earlier in January, a 787 operated by ANA's rival Japan Airlines suffered a battery fire while parked at a Boston airport.
Investigators on both sides are trying to determine why the batteries have overheated and how to fix the problem.
MORE HBJ HEADLINES
Other cars block electric charging stations ESPN viewer losses add to angst for Disney’s profit engine Israel to open Abu Dhabi office for renewable energy Swiss court convicts ex-HSBC employee for leaking bank data United CEO visits workers during leave after heart attack Retailers are pushing sales earlier, and consumers are buying
Our new comment system is not supported in IE 7. Please upgrade your browser here.