Battery manufacturer GS Yuasa says that it will take at least a week to complete an analysis of the battery from an All Nippon Airlines (ANA) Boeing 787 that made an emergency landing in Takamatsu on 16 January.
A spokesman for the company said that it has dispatched a team to Takamatsu to begin analysing the internal and external condition of the lithium-ion battery. He adds that the company has been in close contact with the Japanese government.
He could not give any further details about the investigation into the battery, which is being conducted by the Japan Transport Safety Bureau.
The crew operating the 787 elected to make an emergency landing at Takamatsu on the morning of 16 January, after they received a message that one of the batteries had malfunctioned.
ANA says that an inspection of the battery showed that it was discoloured and some of its electrolyte solution had leaked from its casing.
The incident comes a week after a battery on a Japan Airlines 787 exploded and caused a fire, while the aircraft was on the ground at Boston Logan International Airport.
The US Federal Aviation Administration has grounded all US-registered 787s until Boeing demonstrates that the batteries are safe, with Japan's transport ministry set to follow suit.