Scientists from the Energy Technology Research Institute, AIST in Tsukuba, Japan, have developed a lithium-water electrochemical cell for the controlled generation of hydrogen and electricity. The researchers, headed by Haoshen Zhou, foresee the use of this process in fuel cells for mobile applications. A paper on their work was published in the journal ChemSusChem.
Although direct chemical reactions between water and certain metals—alkali metals including lithium, sodium and others—can produce a large amount of hydrogen in a short time, these reactions are too intense to be controlled.
...Only lithium ions can pass across the LISICON film. The rate of both half reactions within the lithium–water electrochemical cell can be controlled by the current, indicating a controllable hydrogen generation.
Another attractive aspect of this technology is that lithium metal can be produced from salt solutions (e.g., sea water) by using sunlight. In other words, energy from the sun can be “stored” in the metal, and then be used on demand by reacting the lithium in the fuel cell. Recharging the battery would be a matter of replacing the lithium metal cell. _GCC
The device is in its early stages, and inefficient. But a controllable hydrogen generator -- once perfected -- could be useful in several ways.
Labels: electric storage battery, fuel cells