A “Blockchain” Synergy in Conductive Polymer‐Filled Metal–Organic Frameworks for Dendrite‐Free Li Plating/Stripping with High Coulombic Efficiency

Abstract

The performance of lithium‐metal batteries is severely hampered by uncontrollable dendrite growth and volume expansion on the metal anodes. Inspired by the “blockchain” concept in data mining, here we utilize a conductive polymer‐filled metal–organic framework (MOF) as the lithium host, in which polypyrrole (PPy) serves as the “chain” to interlink Li “blocks” stored in the MOF pores. While the N‐rich PPy guides fast Li+ infiltration/extrusion and serves as the nucleation sites for isotropic Li growth, the MOF pores compartmentalize bulk Li deposition for 3D matrix Li storage, leading to low‐barrier and dendrite‐free Li plating/stripping with superb Coulombic efficiency. The as‐fabricated lithium‐metal anodes operate over 700 cycles at 5 mA cm−2 in symmetric cells, and 800 cycles at 1 C in full cells with a per‐cycle capacity loss of only 0.017 %. This work might open a new chapter for Li‐metal anode construction by introducing the concept of “blockchain” management of Li plating/stripping.

Constructing a robust artificial solid electrolyte interphase with a metal–organic framework for a stable Li metal anode

“…41–43 Recently, a few reports have achieved remarkable results in boosting interfacial stability with the aid of MOF artificial SEI films on LMAs. 44–47 Wu and co-workers designed a semi-solid interphase based on coatings of Lewis acidic MOF nanoparticles infiltrated with liquid electrolyte, which effectively suppresses uneven Li deposition and dendrite growth. 48 Nevertheless, the synthesis of highly crystalline MOFs with efficient Li + transport channels and effectual solution to homogenize the Li + flux is still quite necessary to synergistically meliorate LMA interfacial stability.…”

Magnesium fluoride-engineered UiO-66 artificial protection layers for dendrite-free lithium metal batteries

“…With the increasing demand for high-energy-density rechargeable Li-ion batteries (LIBs), Li metal is regarded as the next-generation anode material due to its highest theoretical capacity (3860 mA h g −1 ) and the lowest electrochemical redox potential (−3.04 V vs. standard hydrogen electrodes; SHE), which can satisfy the demand for energy density beyond 500 W h kg −1 . 1–3 However, the practical use of Li metal anodes (LMAs) is hindered by serious safety concerns and poor durability, which are attributed to two major challenges. First, LMAs are susceptible to the uncontrolled formation of Li dendrites on the anode surface owing to the nonuniform distribution of Li + flux during the Li plating/stripping processes.…”

“…First, LMAs are susceptible to the uncontrolled formation of Li dendrites on the anode surface owing to the nonuniform distribution of Li + flux during the Li plating/stripping processes. 2,4 The accumulation of Li dendrites can penetrate the separator, leading to safety hazards, such as short circuits, thermal runaway, and battery explosion. 4 Second, unstable and heterogeneous solid electrolyte interphases (SEIs) result in heterogeneous Li deposition and sluggish Li + transport through fragile SEIs.…”

“…Various strategies, such as electrolyte optimization, 7,8 electrode engineering, 2,9 development of solid-state electrolytes, 10,11 and construction of artificial SEI layers 3,6 have been proposed to address these issues. Among these, the design of an artificial SEI layer has gained substantial interest for suppressing Li dendrite formation at the anodes.…”

MOF‐Derived Materials Enabled Lithiophilic 3D Hosts for Lithium Metal Anode — A Review

“…A growing number of researchers are becoming interested in metal‐organic frameworks (MOFs) derived materials because of their enormous surface area, controlled structure, high porosity, and changeable porosity. [ 54‐65 ] Highly controllable nano materials derived from MOFs, such as metal oxides, metal sulfides and porous carbon structures have been employed in different energy conversion and storage technologies. [ 66‐70 ] The advantages and compositions of MOF‐derived materials have also been summarized well in ref.…”