Sea ​​water to recharge batteries

Researchers at Stanford University led by Yi Cui, have been working to determine the possibility of sea water which has salty character to recharge the batteries. The study, sponsored by the King Abdullah University of Science and Technology (KAUST) and the U.S. Energy Department, examines the sea water as media batteries and call their device as mixing entropy battery. They utilize different levels of salinity of sea water and fresh water to generate electricity to charge batteries.

The device showed more than 100 cycles of efficiency and it can work well with samples of environments. Researchers take salt water from the Pacific Ocean off the coast of California and freshwater from Donner Lake, high in the Sierra Nevada, which are tested in a laboratory. The specific salt ions of the sea water, sodium and chlorine will react with battery electrodes which made of manganese dioxide and silver.

The battery charging resulted in exchange of electrons with ions than shuffles between storage medium and electrodes, while the ion remains in the battery case. The ions will be exchanged freely with the water that flows through it. The cycle is that battery charged up with clean water and little electricity. When the fresh water drained and replace with salty sea water to flows over the electrodes and capture the ions for battery charging.