Modulating the lithiophilicity at electrode/electrolyte interface for high-energy Li-metal batteries

Abstract

Lithium-metal anodes show significant promise for the construction of high-energy rechargeable batteries due to their high theoretical capacity (3860 mAh g -1 ) and low redox potential (-3.04 V vs. a standard hydrogen electrode). When Li metal is used with conventional liquid and solid electrolytes, the poor lithiophilicity of the electrolyte results in an unfavorable parasitic reaction and uneven distribution of Li + flux at the electrode/electrolyte interface. These issues result in limited cycle life and dendrite problems associated with the Li-metal anode that can lead to rapid performance fade, failure and even safety risks of the battery. The lithiophilicity at the anode/electrolyte interface is important for the stable and safe operation of rechargeable Li-metal batteries. In this review, several factors that affect the lithiophilicity of electrolytes are discussed, including surface energy, roughness and chemical interactions. The existing problems and the strategies for improving the lithiophilicity of different electrolytes are also discussed. This review helps to shed light on the understanding of interfacial chemistry vs. Li metal of various electrolytes and guide interfacial engineering towards the practical realization of high-energy

Interface science in polymer‐based composite solid electrolytes in lithium metal batteries

“…Interfacial issues between CSEs and electrodes in single SPE or ISE are of great importance for achieving superior electrochemical performance with a long cycle life and high-rate capability during the operation of SSLMBs. [164][165][166][167] It is well known that Li metal is highly electropositive and chemically reactive, which can spontaneously react with some electrolytes and cause instability at the electrolytes/anode interface. 168,169 In addition, the continuous growth of dendritic crystals can cause short circuits between the anodes and cathodes, which leads to a risk of fire.…”

“…Compared with SPE, single ISEs exhibit higher ionic conductivity and mechanical strength, but they are fragile and show poor contact with the electrodes. Interfacial issues between CSEs and electrodes in single SPE or ISE are of great importance for achieving superior electrochemical performance with a long cycle life and high‐rate capability during the operation of SSLMBs 164–167 …”

Collaborative Assembly of a Fluorine-Enriched Heterostructured Solid Electrolyte Interphase for Ultralong-Life Lithium Metal Batteries

“…The artificial precursor layer K 2 ZrF 6 was fabricated on the lithium metal surface through a facile spin-coating method, and it shows excellent lipophilicity and regulates the contact between the electrode and electrolyte. 28 K 2 ZrF 6 as an inorganic fluoride can be easily processed by the solution method, resulting in a precursor film with a uniform morphology and adjustable thickness. It also shows good chemical stability toward Li metal and high Young's modulus and ionic conductivity.…”

“…Herein, we developed a novel collaborative assembly approach to prepare a fluorine-enriched heterostructured SEI on lithium metal anodes for long-term battery cycling. The artificial precursor layer K 2 ZrF 6 was fabricated on the lithium metal surface through a facile spin-coating method, and it shows excellent lipophilicity and regulates the contact between the electrode and electrolyte . K 2 ZrF 6 as an inorganic fluoride can be easily processed by the solution method, resulting in a precursor film with a uniform morphology and adjustable thickness.…”

“…K 2 ZrF 6 as an inorganic fluoride can be easily processed by the solution method, resulting in a precursor film with a uniform morphology and adjustable thickness. It also shows good chemical stability toward Li metal and high Young’s modulus and ionic conductivity. , Therefore, K 2 ZrF 6 is chosen as the artificial precursor layer to protect the lithium metal anode. Interestingly, the K 2 ZrF 6 film with abundant F atoms shows strong electronegativity, which induces Li + from the electrolyte and assembles a LiF thin layer on the surface.…”