Si2

The Solar Impulse 2 project team has grounded the solar-powered aircraft in Hawaii, following a major failure of its batteries due to overheating.

Solar Impulse said the damage to certain parts of the batteries is irreversible and requires replacements and repair work, which may take several weeks to complete.

As a result, the zero-fuel aircraft is unlikely to make any flights for two to three weeks.

The team said that the overheating could have been caused by excess insulation of the battery compartment.

There was no opportunity to allow the batteries to cool, as the craft was in the air for the whole Nagoya to Hawaii journey.

"There was no opportunity to allow the batteries to cool, as the craft was in the air for the whole Nagoya to Hawaii journey."

The aircraft, which successfully completed its record trip from Japan to Hawaii last week, is on a round-the-world flight.

During the journey, Swiss pilot André Borschberg has broken the record for the longest ever solo flight.

The engineering team is evaluating ways to create better cooling management, as the aircraft is yet to complete the five stages of its 13-leg journey.

Powered by more than 17,000 solar cells on its wings, it started its 35,000km trek in Abu Dhabi on 9 March.

From Hawaii, Solar Impulse co-founder Bertrand Piccard will take the controls for the next crossing to the US mainland.

It will then continue across North America, via Phoenix, mid-US and New York, before flying over the Atlantic to Europe, and on to Abu Dhabi.

Image: Solar Impulse 2 with André Borschberg at the controls landing in Kalaeloa Airport in Hawaii. Photo: courtesy of Solar Impulse SA.