Science - Hydrogen 'balls': Safe fuel of future?

Narayani Ganesh

UPPSALA: The car of the future could be powered by small "ping-pong balls" filled with hydrogen gas. If the project takes off commercially, this
could be a signal contribution from Sweden towards reducing the world's dependence on fossil fuel for transport. This is what astronautics professor and inventor Lars Stenmark of the department of materials science, Angstrom Laboratory, at Uppsala University envisions for a green future.

By storing hydrogen gas in small balls, Stenmark hopes to overcome the risk of fires and explosions. "By storing the gas in round, spherical form, it can withstand twice the pressure that a cylindrical form can. If the car crashes and the tank breaks, the hydrogen-filled balls would just spread out and roll away, and the gas from any broken balls would simply seep out and disappear into the atmosphere without causing harm," he says.

This is just one among many cutting edge research undertaken by faculty at Uppsala, focusing on energy research and new materials.

Maria Stromme, professor of nanotechnology, an engineering physicist, has found a way to extract cellulose from green algae bloom — a poison that is polluting coastlines and killing fish — and convert it into lithium-free batteries. Each fibre is covered with conducting polymer. The sheets so created have a large surface area that is coated with salt water for ion exchange. The sheets are flexible; they can be rolled up or cut into smaller sheets and stacked. Used in textiles, the fibre can make it possible for clothes to change colour! "We need to now extend it from the lab scale to industrial scale," says Maria: "You can even use the cellulose sheets to filter dangerous molecules from polluted water, since you need to treat large surface areas."

How to create inexpensive, "green" batteries with high storage capacity? A 15-member team led by Kristina Edstrom and Josh Thomas, of the department of materials chemistry, is experimenting with new materials to make this possible. Doctoral student Anton Nyten left the battery experiment he was conducting and rushed off to take his wife to the maternity hospital where she gave birth to their daughter, Nelly. He returned five weeks later to find the battery still alive: The "Nelly Effect" refers to the new cathode material discovered for lithium ion batteries using iron and silicon, considerably cheaper than cobalt-based materials.

This amounts to a major step towards enabling manufacture of cheap, environmentally friendly hybrid cars as well as the possibility of cleaner, more efficient heating, creating the potential for larger format batteries that can power vehicles.