Dr Xie Xian Ning from the National University of Singapore’s Nanoscience and Nanotechnology Initiative and his team developed the soft, foldable membrane using a polystyrene-based polymer.
When sandwiched between two charged metal plates it can store charge at 0.2 farads per square centimetre, which is claimed to be well above the typical upper limit for a standard capacitor.
‘Compared to rechargeable batteries and supercapacitors, the proprietary membrane allows for very simple device configuration and low fabrication cost,’ said Dr Xie. ‘Moreover, the performance of the membrane surpasses those of rechargeable batteries, such as lithium ion and lead-acid batteries, and supercapacitors.’
The cost to store each farad is said to be $0.62 (£0.40) compared with about $7 (£4.50) per farad for existing liquid electrolyte based technologies. This translates to an energy cost of 10–20 watt-hour per US dollar for the membrane, as compared to just 2.5 watt-hour per US dollar for lithium ion batteries.
Increasing public concern over the impact of traditional energy sources on the environment and a general shift towards alternative energy sources, for things such as electric cars, has spurred the development.
Hybrid vehicles could benefit from the membrane technology for instant power storage and delivery, improving energy efficiency and reducing carbon emission.
The membrane could also be integrated into solar panels and wind turbines to store and manage the electricity generated, potentially negating the problem of energy instability — a problem these sources are prone to — by storing surplus power and redelivering at times when natural factors are insufficient, such as a lack of solar power during night-time.
The team is now looking for opportunities to work with venture capitalists to commercialise the membrane.