The All Nippon Air (ANA) 787 plane made an emergency landing earlier this week after a rechargeable lithium-ion battery overheated.
The aircraft's landing, which involved deploying escape chutes for passengers and crew to disembark, was the sixth event involving the model in little more than one week.
The risk of fire from overheating batteries has emerged as a major concern for Boeing's cutting-edge new planes since the incident on the domestic flight in Japan, prompting airlines to ground all 50 of the world's operational 787s.
The ANA Dreamliner has remained on the taxiway at Takamatsu airport in southwest Japan since its pilots were forced into the dramatic landing on Wednesday because of a smoke alert apparently linked to the lithium-ion battery.
A team from the US National Transportation Safety Board, which includes members from the Federal Aviation Administration (FAA) and Boeing, arrived in Takamatsu to take part in the Japanese investigation, a spokesman for the Japan Transport Safety Board (JTSB) said.
"We removed the battery yesterday and are today inspecting the plane and its components, alongside the US officials," spokesman Mamoru Takahashi said.
The batteries used for the Dreamliner's advanced electronics are made by Japan's GS Yuasa, one of many contractors in a complex global chain that led to three years of delays before Boeing delivered its first 787 to ANA in 2011.
Electrolyte leaks and burn marks were found on the battery's metal casing, ANA said.
GS Yuasa - while defending its reputation for quality - has warned that the investigation could take weeks.
JTSB investigator Hideyo Kosugi said one theory being considered was that there may have been insufficient overload protection devices.
"I'm sure that too much current or too-high voltage has gone to the battery," Mr Kosugi said.
A prolonged grounding could seriously compound the crisis for Boeing, which had suffered a series of glitches in Japan and the US over the week leading up to the ANA incident.
Hans Weber, an independent security and defence expert, said Boeing had been too optimistic about the benefits of its worldwide outsourcing strategy to build the 787.
Around a third of the plane's components are sourced from Japan.
"Boeing has admitted that it underestimated the level of management oversight and engineering support it needed to provide to its suppliers to make the highly distributed supply chain work," Mr Weber said.
"If Boeing had done a better job at that, it would not have experienced the technical problems it has, in my opinion."
All of the 50 Dreamliners already flying - in Chile, Ethiopia, India, Japan, Poland, Qatar and the US - have now been taken out of service after a global alert was issued this week by the FAA.
Boeing shares lost another 1% in US trading on Thursday and some suppliers such as GS Yuasa have also been hammered on the markets, dropping 18% at one point.
Polish flag carrier LOT - the only European operator of the 787 so far - said it still expected to take delivery of three more planes before the end of March, provided any defects on the plane are eliminated.
Meanwhile Australia's Qantas said it was cutting its request for Dreamliner planes by one, but noted it had planned to do so before the jets were grounded and that it still had 14 on order.
More From Sky News