High-capacity rechargeable batteries based on deeply cyclable lithium metal anodes

Abstract

Discovering new chemistry and materials to enable rechargeable batteries with higher capacity and energy density is of paramount importance. While Li metal is the ultimate choice of a battery anode, its low efficiency is still yet to be overcome. Many strategies have been developed to improve the reversibility and cycle life of Li metal electrodes. However, almost all of the results are limited to shallow cycling conditions (e.g., 1 mAh cm) and thus inefficient utilization (<1%). Here we achieve Li metal electrodes that can be deeply cycled at high capacities of 10 and 20 mAh cm with average Coulombic efficiency >98% in a commercial LiPF/carbonate electrolyte. The high performance is enabled by slow release of LiNO into the electrolyte and its subsequent decomposition to form a LiN and lithium oxynitrides (LiN O)-containing protective layer which renders reversible, dendrite-free, and highly dense Li metal deposition. Using the developed Li metal electrodes, we construct a Li-MoS full cell with the anode and cathode materials in a close-to-stoichiometric amount ratio. In terms of both capacity and energy, normalized to either the electrode area or the total mass of the electrode materials, our cell significantly outperforms other laboratory-scale battery cells as well as the state-of-the-art Li ion batteries on the market.

A Sustainable Solid Electrolyte Interphase for High‐Energy‐Density Lithium Metal Batteries Under Practical Conditions

“…Among various approaches, LiF‐rich SEI (F‐SEI) and LiN x O y ‐contained SEI (N‐SEI) have arisen as exemplary methods to stabilize Li metal under mild conditions recently. F‐SEI is generated by fluorinated solvents or Li salts and N‐SEI is constructed by LiNO 3 additives in carbonate or ether electrolyte, respectively. Generally, F‐SEI and N‐SEI formed by additives as SEI precursors (<5 %, by weight or volume) cannot maintain sustainable due to irreversible exhaustion of limited additives under practical conditions .…”

Metal Organic Framework Derivative Improving Lithium Metal Anode Cycling

“…However, its practical application is severely hindered by the problems of uncontrollable dendrite growth, low Coulombic efficiency (CE) and Li metal deactivation during the electrochemical plating and stripping process . Strategies such as electrolyte engineering, artificial solid electrolyte interphase (SEI), structured electrodes, and separator membrane modification, have been demonstrated to be effective in alleviating these issues via regulation of Li ion transport and/or interfacial properties …”

Lithium Nitrate Solvation Chemistry in Carbonate Electrolyte Sustains High‐Voltage Lithium Metal Batteries

“…Lithium nitrate (LiNO 3 ), with ah igh solubility in ether solvent (typically 5wt% in dimethoxyethane and 1,3-dioxolane) is regarded as ac ritical electrolyte additive in lithium-sulfur (Li-S) batteries and plays ar emarkable roles in inhibiting the "shuttle effect" of lithium polysulfides and dendrite growth of Li metal by stabilizing the Li interface. [13] Therefore, regulating the dissolution behavior of LiNO 3 in carbonate electrolytes and exploring its effect on cycling performance is essential for the development of safe,h igh-voltage LMBs.Herein, we describe the solvation chemistry of LiNO 3 in routine carbonate electrolytes (denoted by EC/DEC) and we propose astrategy for dissolving 1.0 wt %LiNO 3 by introducing atrace amount of copper fluoride (CuF 2 )asadissolution promoter. [11] However,r outine ether-based electrolytes cannot be adopted in high-voltage batteries because of their narrow electrochemical window.…”

“…6 Li NMR spectra and MD Simulations of the electrolyte with and without LiNO 3 .a )6 Li and b)13 CNMR spectra in electrolytes. c) The MD simulation of Li/Cu-N/O/Fradial distribution functions g(r) in E-LiNO 3 .d )The mean square displacement of Li + ions in EC/DEC and E-LiNO 3 electrolytes.…”