Cactus skin discovery to revolutionize electric car industry

Australian scientists have looked to the unassuming cactus in an effort to increase the performance of fuel cells in electric cars, in a discovery which could revolutionize the electric vehicle (EV) industry.

Scientists from the Commonwealth Scientific and Industrial Research Organisation (CSIRO) have developed a membrane similar to one found in the humble cactus which could improve the efficiency of the fuel cells by "a factor of four".

When the membrane is exposed to hot conditions, such as the working parts of a car, it can use its water repellent skin to effectively maintain the hydration of fuel cells, meaning the car can divert power away from other parts such as the power-hungry radiator, which is currently used to keep the cells hydrated.

Aaron Thornton from the CSIRO said the skin works in a similar way to the one found in cactus plants, which thrives in harsh, arid weather by retaining water.

"Fuel cells, like the ones used in electric vehicles, generate energy by mixing together simple gases, like hydrogen and oxygen," Thornton said in a statement on Thursday.

"However, in order to maintain performance, proton exchange membrane fuel cells or PEMFCs need to stay constantly hydrated. At the moment this is achieved by placing the cells alongside a radiator, water reservoir and a humidifier.

"The downside is that when used in a vehicle, these occupy a large amount of space and consume significant power."

According to fellow CSIRO researcher Cara Doherty, the team's new cactus-inspired membrane offers a fuel efficient alternative for EVs.

"A cactus plant has tiny cracks, called stomatal pores, which open at night when it is cool and humid, and close during the day when the conditions are hot and arid," Doherty said.

"This helps it retain water. This membrane works in a similar way. Water is generated by an electrochemical reaction, which is then regulated through nano-cracks within the skin.

"The cracks widen when exposed to humidifying conditions, and close up when it is drier, and this means that fuel cells can remain hydrated without the need for bulky external humidifier equipment.

"We found that the skin made the fuel cells up to four times as efficient in hot and dry conditions."

Meanwhile Professor Young Moo Lee from Hanyang University, which collaborated with the CSIRO, said the development would no doubt have a long-term positive effect on the electric vehicle industry.

"At the moment, one of the main barriers to the uptake of fuel cell electric vehicles is water management and heat management in fuel cell systems," Lee said.

"This research addresses this hurdle, bringing us a step closer to fuel cell electric vehicles being more widely available."