Inhibition of Lithium Dendrite Formation in Lithium Metal Batteries via Regulated Cation Transport through Ultrathin Sub‐Nanometer Porous Carbon Nanomembranes

Abstract

Suppressing Li dendrite growth has gained research interest due to the high theoretical capacity of Li metal anodes. Traditional Celgard membranes which are currently used in Li metal batteries fall short in achieving uniform Li flux at the electrode/electrolyte interface due to their inherent irregular pore sizes. Here, the use of an ultrathin (≈1.2 nm) carbon nanomembrane (CNM) which contains sub‐nanometer sized pores as an interlayer to regulate the mass transport of Li‐ions is demonstrated. Symmetrical cell analysis reveals that the cell with CNM interlayer cycles over 2x longer than the control experiment without the formation of Li dendrites. Further investigation on the Li plating morphology on Cu foil reveals highly dense deposits of Li metal using a standard carbonate electrolyte. A smoothed‐particle hydrodynamics simulation of the mass transport at the anode–electrolyte interface elucidates the effect of the CNM in promoting the formation of highly dense Li deposits and inhibiting the formation of dendrites. A lithium metal battery fabricated using the LiFePO4 cathode exhibits a stable, flat voltage profile with low polarization for over 300 cycles indicating the effect of regulated mass transport.

Depth-Dependent Understanding of Cathode Electrolyte Interphase (CEI) on the Layered Li-Ion Cathodes Operated at Extreme High Temperature

“…Figure S3 shows the Li plating/stripping reaction at a current density of 0.5 mA/cm 2 and an areal capacity of 0.5 mAh/cm 2 . Interestingly, the results clearly indicate that the overpotential for Li plating/stripping is approximately 25 mV and the overpotential is almost constant for more than 100 h at around 30 mV, resulting in the obtained values being in good agreement with the existing scientific literature evaluated using carbonate electrolytes at room temperature. − A slight change in polarization during cycling is relatively negligible when compared to the polarization effect observed in the voltage profiles of Figure a. This Li plating/stripping behavior at high temperature certainly confirms that the Li metal is reversibly involved in electrochemical reactions without any detrimental parasitic reaction in the presence of the ionic liquid electrolyte.…”

An amorphous ZnO and oxygen vacancy modified nitrogen-doped carbon skeleton with lithiophilicity and ionic conductivity for stable lithium metal anodes

“…In recent years, extensive attempts have been made to develop high-performance Li metal batteries, including modifying liquid electrolytes, 7,8,55 engineering a solid electrolyte interface (SEI), 9,10 using solid-state electrolytes, 11–13,56 constructing Li-based alloys, 14–16 improving the wetting ability of the separator, 17–19 and designing hosts for the Li metal anodes. 20–23,57,58 Among these strategies, designing 3D hosts for Li metal anodes can provide a large contact area between the electrode and the electrolyte to reduce local current densities and relieve the volume change during Li plating/stripping, which can result in excellent electrochemical performance.…”

Characterizing the Microstructure of Separators in Lithium Batteries and Their Effects on Dendritic Growth

“…On the other hand, Rajendran et al recently demonstrated the potential of a carbon nanomembrane to regulate ion transport through a Celgard membrane. 16 Other investigations focus on the disruption of dendritic growth along the anode surface. Zhang et al 17 suggest that simply maintaining consistent pressure in the battery cell can suppress dendrites.…”

“…The nanotowers have “lithiophilic” properties which encourage uniform ionic deposition on the anode surface. On the other hand, Rajendran et al recently demonstrated the potential of a carbon nanomembrane to regulate ion transport through a Celgard membrane …”