Supervisory authorities



our social networks



Home > News

To store energy: put water in, keep salt out

published on , updated on

Quick energy storage can be achieved by sudden separation of salt from pure water within concentrated brine. Upon compression of the brine supplemented with selective hydrophobic nanoporous particle salt remains outside the tiny pores while pure water enters in.

This in-volume separation allow to store a large amount of energy as nanoprous particles can sustain giant osmotic pressure of more than 100 MPa far above what can sustain conventional separation membrane. Upon energy requirement, one let the system go back to its expanded state as water is pulled out from the pores by brine spontaneous dilution. Because water transport in the hydrophobic nanopores is almost dissipationless the energy storage and recovery is slightly dependent of the conversion rate. This novel in-volume extraction/dilution process heralds storage devices with targeted power densities larger than ultracapacitors.

The article has appeared in Physical Review Letters and can be accessed on HAL.

Contact :
Cyril Picard maître de conférences Université Joseph Fourier