Mitigating irreversible capacity losses from carbon agents via surface modification

Greatly improved cycling performance has been demonstrated with conformally coated lithium-ion electrodes by atomic layer deposition (ALD) and molecular layer deposition (MLD) techniques. This paper reports the impact of coating on the electrode additives towards mitigating undesired parasitic reactions during cycling. The ALD and MLD coatings with conformality and atomic scale thickness control effectively stabilize the surface of the electrode components, and the current collector, resulting in the increase of coulombic efficiency throughout cycling. The organic fragment integrated into the recently developed MLD process allows the coating to possess excellent mechanical properties and enhanced ionic conductivity, which significantly reduces cell polarizations throughout cycling. This work validates the importance of ALD and MLD as surface modifiers and further demonstrates their versatility and compatibility with lithium-ion battery technology. (C) 2014 Elsevier B.V. All rights reserved.