Long Cycle Life Lithium Metal Batteries Enabled with Upright Lithium Anode. (21st February 2019) - Chen, Yuqing
Abstract: The lithium metal anode is the holy grail of the battery field due to its lowest reduction potential and high specific capacity; however, its application is hindered by severe safety hazards and inferior cyclic stability due to dendrites and unstable solid electrolyte interphase (SEI). Aiming at these problems, a coiled Li anode with a unique upright structure is proposed. The upright structure endows coiled Li anode with abundant inner reaction interface/space/mass for lithium deposit/storage/transport, which can induce the inner growth of Li dendrites and SEI. The Li + transport/deposit behavior and mechanism of coiled Li anode are clarified via in situ observation and numerical simulation. Benefiting from the small volume expansion and sufficient Li + transport, the coiled Li anodes combined with Li4 Ti5 O12 cathodes achieve a long life of over 2000 cycles at 5C with a reversible capacity of 129 mAh g −1 and 100% Coulombic efficiency. Abstract : Upright Li anodes are proposed to make planar Li stand up and realize the inner growth of Li dendrites, owing to the broad reaction interface, large Li storage space, and durable Li + transport. Long life lithium metal batteries are achieved over 2000 cycles with a unique anode structure.