Regulating Zn Deposition via an Artificial Solid–Electrolyte Interface with Aligned Dipoles for Long Life Zn Anode

Aqueous zinc ion batteries show prospects for next-generation renewable energy storage devices.However,the practical applications have been limited by the issues derived from Zn anode.As one of serious problems,Zn dendrite growth caused from the uncontrollable Zn deposition is unfavorable.Herein,with the aim to regulate Zn deposition,an artificial solid–electrolyte interface is subtly engineered with a perovskite type material,BaTiO3,which can be polarized,and its polarization could be switched under the external electric field.Resulting from the aligned dipole in BaTiO3 layer,zinc ions could move in order during cycling process.Regulated Zn migration at the anode/electrolyte interface contributes to the even Zn stripping/plating and confined Zn dendrite growth.As a result,the reversible Zn plating/stripping processes for over 2000 h have been achieved at 1 mA cm^(−2) with capacity of 1 mAh cm−2.Furthermore,this anode endowing the electric dipoles shows enhanced cycling stability for aqueous Zn-MnO2 batteries.The battery can deliver nearly 100%Coulombic efficiency at 2 Ag^(−1) after 300 cycles.

2.5μm-Thick Ultrastrong Asymmetric Separator for Stable Lithium Metal Batteries

Lithium metal batteries(LMBs)are considered the ideal choice for high volumetric energy density lithium-ion batteries,but uncontrolled lithium deposition poses a significant challenge to the stability of such devices.In this paper,we introduce a 2.5μm-thick asymmetric and ultrastrong separator,which can induce tissue-like lithium deposits.The asymmetric separator,denoted by utPE@Cu_(2)O,was prepared by selective synthesis of Cu_(2)O nanoparticles on one of the outer surfaces of a nanofibrous(diameter~10 nm)ultrastrong ultrahigh molecular weight polyethylene(UHMWPE)membrane.Microscopic analysis shows that the lithium deposits have tissue-like morphology,resulting in the symmetric lithium cells assembled using utPE@Cu_(2)O with symmetric Cu_(2)O coating exhibiting stable performance for over 2000 h of cycling.This work demonstrates the feasibility of a facile approach ultrathin separators for the deployment of lithium metal batteries,providing a pathway towards enhanced battery performance and safety.

Carbon materials for stable Li metal anodes: Challenges, solutions, and outlook

Lithium(Li)metal is regarded as the ultimate anode for next-generation Li-ion batteries due to its highest specific capacity and lowest electrochemical potential.However,the Li metal anode has limitations,including virtually infinite volume change,nonuniform Li deposition,and an unstable electrode-electrolyte interface,which lead to rapid capacity degradation and poor cycling stability,significantly hindering its practical application.To address these issues,intensive efforts have been devoted toward accommodating and guiding Li deposition as well as stabilizing the interface using various carbon materials,which have demonstrated excellent effectiveness,benefiting from their vast variety and excellent tunability of the structure-property relationship.This review is intended as a guide through the fundamental challenges of Li metal anodes to the corresponding solutions utilizing carbon materials.The specific functionalities and mechanisms of carbon materials for stabilizing Li metal anodes in these solutions are discussed in detail.Apart from the stabilization of the Li metal anode in liquid electrolytes,attention has also been paid to the review of anode-free Li metal batteries and solid-state batteries enabled by strategies based on carbon materials.Furthermore,we have reviewed the unresolved challenges and presented our outlook on the implementation of carbon materials for stabilizing Li metal anodes in practical applications.

Artificial solid-electrolyte interface facilitating uniform Zn deposition by promoting chemical adsorption

Zn-air batteries are promising energy storage and conversion systems to replace the conventional lithiumbased ones.However,their applications have been greatly hindered by the formation of Zn dendrites and ZnO passivation layer on the Zn anodes.Herein,we report the fabrication of an artificial protective layer comprised of N-doped threedimensional hollow porous multi-nanochannel carbon fiber with well-dispersed TiO_(2) nanoparticles(HMCNF).The incorporated TiO;nanoparticles and N dopants improve the ion flux distribution and promote the surface adsorption,facilitating the interfacial pseudocapacitive behaviors during Zn deposition.The hierarchical architecture also induces homogenous electric field distribution at the anode/electrolyte interface.Accordingly,the deposition behavior of Zn is regulated,giving rise to enhanced utilization and rechargeability of Zn.When integrated in alkaline Zn-air batteries,the HMCNF-coated Zn anodes exhibit improved electrochemical performances relative to those with the bare Zn anodes,demonstrating a versatile strategy to boost energy storage of metal anodes through optimizing surface adsorption properties.