High-Coulombic-Efficiency Lithium Metal Anodes Enabled by Three-Dimensional Lithiophilic Nanostructures with Multiscale Porosity

Abstract

The formation and growth of lithium dendrites have dramatically limited the application of lithium metal anodes due to their shortened lifespan and safety hazards. We fabricated a three-dimensional (3D) matrix comprised of interconnected NiO/Ni nanobranches linking carbon fibers in carbon cloth (NiO/Ni/CC). In-situ transformation of NiO to Li 2 O/Ni renders stronger binding between the carbon cloth and lithium ions, guiding homogeneous lithium plating in nano-and microscale pores of nanobranches. In parallel, the macroscale pores between carbon fibers in a 3D framework facilitate the infiltration of electrolytes and thus regulate ion transport. The NiO/Ni/CC showcases excellent electrochemical reversibility upon lithium plating/stripping with an exceptionally high Coulombic efficiency of 99.97% for 800 cycles, and an excellent cycling stability of 700 h at a a high current density of 3 mA cm −2 for a high areal capacity of 3 mAh cm −2 . Moreover, full cells paired with both LiFePO 4 and LiNi 0.5 Co 0.2 Mn 0.3 O 2 cathodes demonstrate a superior rate capability and stability. This work manifests an efficient and scalable route on the dual design of lithiophilicity and porosity of 3D lithium metal hosts for high-performance lithium metal batteries.

Multifunctional and Seamlessly Integrated Soft/Rigid Interphase Realizing a Stable Lithium-Metal Anode for a High-Performance Lithium-Metal Battery under a Lean Electrolyte

“…Lithium (Li) metal anodes have attracted extensive attention due to their great potential in next-generation high-energy-density Li-metal batteries (LMBs), especially in high-voltage Lia∥LiNi 0.8 Co 0.1 Mn 0.1 O 2 applications. − Nevertheless, the highly reactive Li-metal anode will react with the electrolyte to generate a weak solid electrolyte interphase (SEI), which cannot accommodate large volume changes during cycling. , This induces the continuous formation of a large amount of “dead Li” and leads to the rapid depletion of the electrolyte. , Therefore, the SEI properties, including electronic resistivity, Li + diffusion rate, mechanical strength, etc., directly determine the Li deposition behaviors. , According to previous reports, the natural SEI in an ether-based/ester-based electrolyte is normally composed of undesirable organic (LiR)/inorganic (Li 2 CO 3 and Li 2 O) components, which cannot ensure ideal fast Li + transport and sufficient electronic insulation. , Therefore, it eventually leads to the formation of Li nuclei outside the SEI layer and the loss of necessary electron conduction . In addition, the naturally generated SEI also cannot provide enough mechanical strength to accommodate huge volume changes during cycling, resulting in the continuous rupture of the SEI and the rapid consumption of the electrolyte. − …”