Dynamic gel as artificial interphase layer for ultrahigh-rate and large-capacity lithium metal anode

Abstract

Constructing a stable artificial solid-electrolyte interphase has become one of the most effective strategies to overcome the poor reversibility of lithium metal anode, yet the protection role is still insufficient at elevated current densities over 10 mA cm−2 and large areal capacities over 10 mAh cm−2. Herein, we propose a dynamic gel with reversible imine groups, which is prepared via a cross linking reaction between flexible dibenzaldehyde-terminated telechelic poly(ethylene glycol) and rigid chitosan, to fabricate a protective layer for Li metal anode. The as-prepared artificial film shows combined merits of high Young’s modulus, strong ductility and high ionic conductivity. When the artificial film is fabricated on a lithium metal anode, the thin protective layer shows a dense and uniform surface owing to the interactions between the abundant polar groups and lithium metal. Besides, the polar groups in the artificial film can homogenize the distribution of Li+ at the electrode/electrolyte interface. As a result, cycle stability over 3200 h under an areal capacity of 10 mAh cm−2 and a current density of 10 mA cm−2 has been obtained for the protected lithium metal anodes. Moreover, cycling stability and rate capability has been also improved in the full cells.

Storage Performance and Structure Degradation Mechanism of Single-Crystal Ni-Rich Material

“…The high potential difference during the first charge/discharge is caused by the removal of residual lithium compounds on the stored SCNCM surface. 49,50 The results indicate that many impurities appear on the SCNCM surface after long-time storage, affecting the transfer of Li ions. In the charge/ discharge curves, the SCNCM materials stored for 7 days have an apparent overvoltage peak at the beginning of charging.…”

Organic Nitrate Additive for High‐Rate and Large‐Capacity Lithium Metal Anode in Carbonate Electrolyte

“…Therefore, Li metal anode has regained lots of attentions owing to the ultrahigh theoretical specific capacity (3860 mAh g −1 ) and the lowest redox potential (−3.04 V vs standard hydrogen electrode). [ 1–5 ] Unfortunately, the poor reversibility and the uncontrollable dendrite growth still limit the commercial application of Li metal anode. Specifically, the high activity of Li metal induces the formation of a SEI at the interface of Li metal/electrolyte.…”

Insight into the Effect of Cu2+ Doping on CuxNb2–xO5–3/2x for High-Power Lithium-Ion Batteries

“…With the major changes in the global energy structure, high-energy density batteries have captured people’s attention. , However, as the commercially used anode material in lithium-ion batteries (LIBs), graphite is restricted by its inferior rate capability and safety issues, while Li 4 Ti 5 O 12 suffers from its low specific capacity, which could not meet the urgent demand for high-quality batteries . The alloy-type negative materials are also subject to their huge volume effect .…”