Technology Review reports that new advances may make high energy lithium-sulphur batteries practical at last - Revisiting Lithium-Sulfur Batteries.

Lithium-sulfur batteries, which can potentially store several times more energy than lithium-ion batteries, have historically been too costly, unsafe, and unreliable to make commercially. But they're getting a fresh look now, due to some recent advances. Improvements to the design of these batteries have led the chemical giant BASF of Ludwigshafen, Germany, to team up with Sion Power, a company in Tucson, AZ, that has already developed prototype lithium-sulfur battery cells.

"Compared to existing technologies used in electric vehicles, the plan is to increase driving distance at least 5 to 10 times," for a given-size battery, says Thomas Weber, CEO of a subsidiary of BASF called BASF Future Business. Other experts say that a threefold improvement is a more reasonable estimate, but that would still be an impressive jump in performance. Weber says that BASF's expertise in materials will help Sion Power further improve its technology and bring it to market faster. He declined to provide details of the arrangement, however, including how much money is involved and how the companies will share any profits.

Lithium-sulfur batteries have one electrode made of lithium and another made of sulfur that is typically paired with carbon. As with lithium-ion batteries, charging and discharging the battery involves the movement of lithium ions between the two electrodes. But the theoretical capacity of lithium-sulfur batteries is higher than that of lithium-ion batteries because of the way the ions are assimilated at the electrodes. For example, at the sulfur electrode, each sulfur atom can host two lithium ions. Typically, in lithium-ion batteries, for every host atom, only 0.5 to 0.7 lithium ions can be accommodated, says Linda Nazar, a professor of chemistry at the University of Waterloo.

Making materials that take advantage of this higher theoretical capacity has been a challenge. One big issue has been that sulfur is an insulating material, making it difficult for electrons and ions to move in and out. So while each sulfur atom may in theory be able to host two lithium ions, in fact often only those atoms of sulfur near the surface of the material accept lithium ions.

Reuters has a report on a Japanese plant o increase shipping fuel efficiency by installing solar panels on board - Japan firms to work on solar-powered ship.

The race to go green has taken to the high seas with two Japanese companies saying they would begin work on the world's first ship to have propulsion engines partially powered by solar energy.

Japan's biggest shipping line Nippon Yusen KK and Nippon Oil Corp said solar panels capable of generating 40 kilowatts of electricity would be placed on top of a 60,000 tonne car carrier to be used by Toyota Motor Corp.

The solar panels would help conserve up to 6.5 percent of fuel oil used in powering diesel engines that generate electricity at any given moment.

A UK-built solar-powered plane has set an unofficial world endurance record for a flight by an unmanned aircraft. The Zephyr-6, as it is known, stayed aloft for more than three days, running through the night on batteries it had recharged in sunlight.

The flight was a demonstration for the US military, which is looking for new types of technology to support its troops on the ground. Craft like Zephyr might make ideal platforms for reconnaissance. They could also be used to relay battlefield communications.

Chris Kelleher, from UK defence and research firm QinetiQ, said Unmanned Aerial Vehicles (UAVs) offer advantages over traditional aircraft and even satellites. "The principal advantage is persistence - that you would be there all the time," he told BBC News. "A satellite goes over the same part of the Earth twice a day - and one of those is at night - so it's only really getting a snapshot of activity. Zephyr would be watching all day." ...

At first sight, the propeller-driven Zephyr looks to be just another model aircraft, and it is even launched by hand. But this "pilotless" vehicle with its 18-metre wingspan incorporates world-leading technologies.

Its structure uses ultra-lightweight carbon-fibre material; and the plane flies on solar power generated by amorphous silicon solar arrays no thicker than sheets of paper. These are glued over the aircraft's wings.

To get through the night, the propellers are powered from lithium-sulphur batteries which are topped up during the day.

"A lot of effort has gone into power storage and light-weighting the systems," explained Mr Kelleher. "Lithium sulphur is more than double the energy density of the best alternative technology which is lithium polymer batteries. "They are an exceptional performer. We've worked with the Sion Corporation. They've had them in development for years. We're actually the first application in the world for them."