High-Performance Rechargeable Lithium-Chlorine Batteries with ALD Conformal Starburst Porous Graphene Positive Electrodes.

Rechargeable alkali metal-chlorine batteries are emerging as a promising high-energy-density solution. However, they confront significant challenges, including the primary issue stemming from the weak binding affinity of cathode materials for Cl, which leads to a sluggish and inadequate supply of Cl during the redox reactions, resulting in a shortened cycle life and low Coulombic efficiency (CE), particularly when operating at ultrahigh specific capacity outputs. Herein, an AlO-skinned heterostructured starburst porous graphene with conformal metasurfaces (AlO@rGO) is reported, crafted from a hierarchical porous starburst graphene arranged in a unique layered structure by the PTFE microemulsion skin effect, leveraging subsequent fluidized bed atomic layer deposition (FBALD) of AlO groups. AlO@rGO features superhydrophilicity, effective adsorption, fast kinetics from stable dynamic respiratory interface, high electrical and thermal conductivity anisotropy, intelligent thermal management and safe operation over a wide temperature range. Consequently, the Li-Cl@AlO@rGO battery achieves an ultrahigh discharge specific capacity of 5000 mAh g at ≈100% CE, and even delivers stable cycling over 200 cycles with 2000 mAh g at an average CE of 99.8% under low temperature environment of -40 °C. The scalable heterostructure approach offers a sustainable perspective of the development of functionalized metamaterials and metasurfaces for next-generation safe and energy-dense batteries and broader applications.