Battery damage grounds Solar Impulse 2 until 2016

The second leg of Solar Impulse 2's epic solar-powered flight across the Pacific has been postponed until 2016 while the plane undergoes repairs to its damaged batteries.

The plane’s batteries, which provide power for night flying, overheated during its recent five-day, 4,480-mile flight from Japan to Hawaii, forcing the Solar Impulse team to push the next leg of the journey to April 2016.

The batteries will now undergo maintenance repairs, according to a statement released by the Solar Impulse team Wednesday. “The damage to the batteries is not a technical failure or a weakness in the technology,” the team said, noting that the temperature effect of quick ascents and descents in tropical climates was not properly anticipated.

Initially, the team projected that it would take several weeks to repair the damaged batteries, but updated their estimate Wednesday.

Related: Solar Impulse 2’s epic journey in pictures

“Irreversible damage to certain parts of the batteries will require repairs which will take several months,” the team explained. “In parallel, the Solar Impulse engineering team will be studying various options for better cooling and heating processes for very long flights.”

The University of Hawaii will host the airplane in its hangar at Kalaeloa airport while the maintenance work is completed. Post maintenance check flights will start in 2016 to test the new battery heating and cooling systems, according to the Solar Impulse team.

Piloted by Andre Borschberg, Solar Impulse 2 arrived in Hawaii July 3, completing the longest and riskiest leg of its round-the-world odyssey. During the journey, Borschberg broke the records for longest solar-powered flight in terms of distance and duration and longest non-stop solo flight without refueling.

Despite the battery problems, Borschberg is determined to continue the historic round-the-world flight. “We will never give up!” he  tweeted Wednesday.

Solar Impulse 2, a larger version of a single-seat prototype that first flew five years ago, is made of carbon fiber and has 17,248 solar cells built into the wing that supply the plane with renewable energy, via four motors. The solar cells recharge four lithium polymer batteries.

The aircraft typically flies between 30 mph and 40 mph, although this can increase and decrease significantly depending on wind speed.

The plane is the brainchild of explorer and Solar Impulse Chairman Bertrand Piccard, who is taking it in turns with his fellow Swiss pilot Borschberg to fly the solar-powered aircraft on its journey across the globe.

Piccard sees the high-tech plane as proving the potential of renewable energy and clean technology. “This was my vision when I created that project – it was to have an airplane that can fly with no fuel,” he told, during a phone interview last month. “This is fantastic, to prove that clean technology can achieve [the] impossible.”

Related: Solar Impulse 2 passes ‘point of no return’ in audacious attempt to cross the Pacific

The Solar Impulse chairman also believes that the solar plane could spark increased interest in technologies such as LED lights and electric cars, as well as lightweight vehicles.

Solar Impulse 2 set off from Abu Dhabi in March, and has stopped in Oman, India, Myanmar and Nanjing, China, en route to an unscheduled stop in Nagoya, Japan.

The plane originally left Nanjing, China, for Hawaii, but diverted to Japan on June 1 because of unfavorable.

After Hawaii, the second Pacific leg of the journey will take the plane to Phoenix. Solar Impulse 2 is slated to stop in New York before flying over the Atlantic Ocean. It will then stop in southern Europe or North Africa, depending on weather conditions.

Follow James Rogers on Twitter @jamesjrogers