Batteries

The current state of development in battery technology is not adequate for modern needs in renewable energy. Li-ion batteries provide the greatest capacity, but Li metal anodes can lead to dendrite growth and catastrophic failure. We can reduce this by pulse charging, but this slows the charging rate [#1056, 1117, 1133]. To reduce the danger of dendrite growth, we can use polymer [#1016] or ionic liquid electrolytes, but this decreases the Li mobility. We can replace Li anode with Na, but this reduces capacity (see [#1168]). We can use other electrodes but this generally reduces capacity [1154, 1098, 1046, 1068]. These are all areas that we have modeled at the atomistic level with some success in understanding some of the issues. The most important area for the theory is to understand may be the nature of the solid–electrolyte interface (SEI). The Li-ions and Li metal electrode react with the electrolyte to produce the SEI, which must play an essential role in charging and discharging since the ions must be transported through this layer and then must be desolvated as they are deposited on the Li metal surface. We have used QM to characterize the SEI for the Li electrode-ionic liquid interface.