Archer Group paper published in Nature Communications
A highly reversible room-temperature lithium metal battery based on crosslinked hairy nanoparticles
Over the past century significant amount of research and development has been focused on meeting the ever-growing energy demand. This has led to an extensive search for a safe, portable, high-energy storage technology. Secondary Lithium Metal Batteries (LMBs), where metallic lithium serves as an anode, have received a great deal of attention in this regard due to their high energy density, lightweight and high working potential. However, repeated cycles of charge and discharge in these batteries lead to uneven deposition of Li-ion on the electrodes, which subsequently result in formation of dendritic structures causing internal short circuits and cell failure that may eventually lead to an explosion. Commercially available batteries comprise of a graphitic anode instead of lithium metal thus, compromising the power density and cost.
Recently Archer group designed a membrane, which serves as electrolyte-cum-separator for Lithium metal battery increasing their efficiency and cyclability by several folds. The membrane was formed by crosslinking hairy silica nanoparticles with high molecular weight polymer having low glass transition temperature. This feature renders them an ability to operate efficiently even at room temperatures due to their uncompromised high ionic conductivities. Batteries with these membranes exhibit unprecedented high short circuit times even at room temperature, which have been difficult to achieve in existing nanocomposite electrolytes. Presence of silica in these membranes provides a high mechanical modulus that inhibits the dendrite growth and also prevents electrolyte leakage. Furthermore, the crosslinked membrane can act synergistically with electrolyte additives to prevent the parasitic reactions of the Lithium electrode that leads to capacity fade, thus enhancing the utilizable energy of a commercial battery for hundreds of cycles.
To read the full article visit: http://www.nature.com/ncomms/2015/151204/ncomms10101/full/ncomms10101.html