Energy-storing membrane may 'perform better than batteries'

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.