Is it possible to build a battery using the elastic property of graphene?
Here is the stress-strain curve of graphene. Image source: https://www.researchgate.net/figure/Stress-strain-curves-of-defect-free-graphene_fig2_313777746
Based on the figure, with 0.1 m^3 graphene fiber, by applying 80 GPa force, graphene fiber will stretch about 10%, then 80 GPa * 0.1 m^3 * 10% * 0.5 = 400 MJ energy is stored. The energy can be released by winding the fiber to the gear.
As a comparison, a standard car with 65 liters of gasoline contains the energy of 65L * 0.77 kg/L * 45 MJ/kg = 2252.25 MJ, while the efficiency of a gasoline car is roughly 25%.
- What is the limitation of this approach?
- If it works, is any other material better than graphene? For example, materials such a rubber band which can be stretched 700%.
Elastic and plastic deformation of graphene: https://arxiv.org/pdf/0907.0501.pdf