Potassium Metal Anodes Research Articles

Weakly Solvating Ether‐Based Electrolyte Constructing Anion‐Derived Solid Electrolyte Interface in Graphite Anode toward High‐Stable Potassium‐Ion Batteries

AbstractLow‐cost graphite has emerged as the most promising anode material for potassium‐ion batteries (PIBs). Constructing the inorganic‐rich solid electrolyte interface (SEI) on the surface of graphite anode is crucial for achieving superior electrochemical performance of PIBs. However, the compositions of SEI formed by conventional strongly solvating electrolytes are mainly organic, leading to the SEI structure being thick and causing the co‐intercalation behavior of ions with the solvent. Herein, a weakly solvating electrolyte is applied to weaken the cation‐solvent interaction and alter the cation solvation sheath structures, conducing to the inorganic composition derived from anions also participating in the formation of SEI, together with forming a uniformly shaped SEI with superior mechanical properties, and thus improving the overall performance of PIBs. The electrolyte solvation structure rich in aggregated ion pairs (AGGs) (69%) enables remarkable potassium‐ion intercalation behavior at the graphite anode (reversible capacity of 269 mAh g−1) and highly stable plating/stripping of potassium metal anode (96.5%). As a practical device application, the assembled potassium‐ion full‐battery (PTCDA//Graphite) displays superior cycle stability. The optimizing strategy of cation solvation sheath structures offers a promising approach for developing high‐performance electrolytes and beyond.

Cyclic Ether-Based Electrolyte with a Weak Solvation Structure for Advanced Potassium Metal Batteries.

Potassium metal batteries (PMBs) are promising candidates for large-scale energy storage. Conventional carbonate electrolytes exhibit unsatisfactory thermodynamic stability against potassium (K) metal anode. Linear ether is widely adopted because of its compatibility with K metal, but the poor oxidation stability restricts the application with high-voltage cathodes. Herein, a weakly solvating cyclic ether is proposed as a solvent to stabilize the K-electrolyte interface and build a robust solid-electrolyte interphase (SEI). This weakly solvating electrolyte (WSE) possesses an anion-dominated solvation structure, which facilitates the anion decomposition for constructing an inorganic-rich SEI. The superior mechanical properties of the SEI, as examined by atomic force microscopy, prevent the SEI from fracture. Consequently, this WSE achieves highly reversible plating/stripping behavior of K metal for 1300h with a high average Coulombic efficiency of 99.20%. Stable full cells are also demonstrated with a high-voltage cathode at harsh conditions. This work complements the design of WSEs for advanced PMBs by cyclic ether solvents.

Ultrahigh Potassium Storage Capacity of Ca2Si Monolayer with Orderly Multilayered Growth Mechanism.

As the rising renewable energy demands and lithium scarcity, developing high-capacity anode materials to improve the energy density of potassium-based batteries (PBBs) is increasingly crucial. In this work, a unique orderly multilayered growth (OMLG) mechanism on a 2D-Ca2Si monolayer is theoretically demonstrated for potassium storage by first-principles calculations. The global-energy-minimum Ca2Si monolayer is a semiconductor with isotropic mechanical properties and remarkable electrochemical properties, such as a low potassium ion migration energy barrier of 0.07eV and a low open circuit voltage ranging from 0.224 to 0.003V. Most notably, 2D-Ca2Si demonstrates an ultrahigh theoretical specific capacity of 5459mAhg-1 and a total specific capacity of 610mAhg-1, reaching up to 89% of the capacity of a potassium metal anode. Remarkably, the OMLG mechanism facilitates stable, dendrite-free deposition of hcp-K metal layers on the 2D-Ca2Si surface, where the ultrahigh and gradually converging lattice match as the layers increase is the key to achieving theoretically near-infinite growth. The study theoretically demonstrates the Ca2Si monolayer a highly promising anode material, and offers a novel potassium storage strategy for designing 2D anode materials with high specific capacity, rapid potassium-ion migration, and good safety.

Dual‐Gradient Engineering of Conductive and Hierarchically Potassiophilic Network for Highly Stable Potassium Metal Anode

AbstractPotassium (K) metal anodes are the most competitive candidates for low‐cost and high‐energy density rechargeable batteries. However, uncontrolled K dendrite growth strictly impedes the practical application of K metal anodes. Herein, a potassiophilic and conductive dual‐gradient free‐standing host (named TS‐PKS) composed of the bottom layer with Ti3CN and F doped SnO2 (F‐SnO2) and the top layer with perfluorinated sulfonic acid K (PFSA‐K) and ordered mesoporous silica (SBA15) is constructed to achieve dendrite‐free K deposition. The potassiophilicity and conductivity of the TS‐PKS host increase along with the depth direction to generate a bottom‐up dual‐gradient of K+ affinity and electroconductivity. Such bottom‐up dual‐gradient of K+ affinity and electroconductivity can synergistically manipulate uniform K metal deposition following the bottom‐up manner, preventing the notorious K dendrite growth. As a result, the TS‐PKS@K symmetric cell can stably cycle over 2800 h at 0.5 mA cm−2/0.5 mAh cm−2. Meanwhile, the TS‐PKS@K//PTCDA full battery also exhibits an initial specific capacity of 118.3 mAh g−1 at a high current density of 500 mA g−1 and maintains up to 81.1 mAh g−1 after 1000 cycles. This novel dual‐gradient strategy design offers a straightforward approach to effectively manipulate K metal deposition manner for achieving dendrite‐free K metal anodes.

Introduction of a nitrate anion with solubility mediator in a carbonate-based electrolyte for a stable potassium metal anode

In this study, sodium nitrate (NaNO3) dissolves in a carbonate electrolyte for K-metal batteries (KMBs) using a dimethylacetamide (DMA) solvent with a higher Gutmann donor number than that of NO3−. The K-metal anode in 0.02 M NaNO3 electrolyte exhibits enhanced stability due to the modified solid-electrolyte interphase (SEI) layer resulting from the preferential reduction of NaNO3. Reduced NaNO3 forms ionically conductive and mechanically robust compounds in the SEI layer. This compound plays a critical role in altering the morphology of electrodeposited K-metal from dendritic to spherical, reducing the barrier energy of nucleation potential for K-ions. These unique features make K-metal highly resistant to dendrite formation and aggressive electrolyte chemistry. Therefore, the K-metal anode in the proposed electrolyte containing 0.02 M NaNO3 additive ensures excellent cycle life with stable Coulombic efficiency in both symmetrical K/K half cells and full-cells coupled with a Prussian green FeFe(CN)6 cathode.

Nanomesh NiO-modified carbon cloth for highly efficient self-supporting potassium metal anodes

Potassium metal is one of the most promising anode materials for potassium-ion batteries owing to its low cost and ability to withstand high current density and relatively low operating potential. However, it is restricted from being used in practical implementations because of its high reactivity and disordered dendrite growth. To circumvent these issues, we stabilize potassium metal anodes by growing NiO with high potassium affinity and interconnected network porous structure on carbon cloth fibers (CC-NiO). A symmetric cell assembled from a composite material formed by infiltrating molten K into CC-NiO (K@CC-NiO) can cycle stably for 1840 h at a low overpotential of 33 mV. Furthermore, the first-cycle discharge capacities of the full batteries with carbon nanotubes-interwoven KFeSO4F microspheres (KFSF@CNTs) and perylene-3,4,9,10-tetracarboxylic dianhydride (PTCDA) as the cathodes are 101.4 and 105.1 mAh g−1, respectively. The capacity retention of KFSF@CNTs||K@CC-NiO full battery after 1000 cycles is 79.3 %, and the capacity retention of PTCDA||K@CC-NiO full battery after 800 cycles is 70.2 %. The strategy of utilizing NiO as an efficient potassium metal nucleation anchor opens up a new direction for the development of high-energy and long-cycle-life potassium metal batteries.

Hydroxyl-Decorated Carbon Cloth with High Potassium Affinity Enables Stable Potassium Metal Anodes.

Highly anticipated potassium metal batteries possess abundant potassium reserves and high theoretical capacity but currently suffer from poor cycling stability as a result of dendritic growth and volume expansion. Here, carbon cloths modified with different functional groups treated with ethylene glycol, ethanolamine, and ethylenediamine are designed as 3D hosts, exhibiting different wettability to molten potassium. Among them, the hydroxyl-decorated carbon cloth with a high affinity for potassium can achieve molten potassium perfusion (K@EG-CC) within 3s. By efficiently inducing the uniform deposition of metal potassium, buffing its volume expansion, and lowering local current density, the developed K@EG-CC anode alleviates the dendrite growth issue. The K@EG-CC||K@EG-CC symmetric battery can be cycled stably for 2100h and has only a small voltage hysteresis of ≈93 mV at 0.5 mAcm-2 . Moreover, the high-voltage plateau, high energy density, and long cycle life of K metal full batteries can be realized with a low-cost KFeSO4 F@carbon nanotube cathode. This study provides a simple strategy to promote the commercial applications of potassium metal batteries.

Designing Electrolytes with Steric Hindrance and Film‐Forming Booster for High‐Voltage Potassium Metal Batteries

AbstractPotassium metal batteries coupling with high‐voltage manganese hexacyanoferrate (MnHCF) cathodes are promising candidates for energy storage devices. Ethers are the primary electrolyte solvent candidates for reversible potassium metal anodes, but their poor oxidative stability at high voltage restricts the application. Taking advantage of the steric hindrance, a dilute (1 m) non‐fluorinated ether with extended alkyl groups is designed to reduce the solvation capability to K ions, thus suppressing the solvent decomposition and tailoring the interphase composition on both cathode and anode sides. The accompanying high viscosity associated with the long alkyl groups can be readily resolved by incorporating an S‐containing additive, which further boosts the oxidative stability to 4.6 V. Furthermore, the additive contributes to the S‐rich organic species among the interphases that inhibit the metal dissolution of the cathode and induce the homogenous K deposition through promoted kinetics. Benefiting from the stable interphases and restricted side reactions, the dilute non‐fluorinated ether‐based electrolyte enables the stable cycling of MnHCF||K cell for over 200 cycles with a high Coulombic efficiency of over 99.4% under a negative/positive capacity ratio of 4.

A 3D structural NC/ZnO@carbon cloth matrix as a potassiophilic host for a dendrite-free potassium metal anode

Metallic potassium batteries (PMBs), with natural abundance and relatively low operating potentials, are considered one of the mighty alternatives to lithium-ion batteries.

Detrimental Effects of Metal Foil’s Surface Imperfections on Metal Plating/Stripping and Facile Solutions

Rechargeable metal batteries have attracted great interest and are considered one of the most promising high-energy density storage systems. These devices benefit from the large specific volumetric capacities and high specific gravimetric capacities of metal anodes. Foils or sheets are the most common form of anode for metal batteries since they are massively manufactured and readily accessible. But short circuits from dendrites grown on metal foil anodes can dramatically decrease the cycling stability and lead to premature failure of the batteries.Homogeneous metal plating/stripping is the key to avoiding dendrite formation. And the surface uniformity of metal electrodes is crucial for the initial nucleation and growth, which greatly affects the subsequent deposition. Here, we show that manufacturing-induced defects, including surface imperfections such as a roughened surface, orange peel features, microcracks, scratches, or fold lines, and unpolished edges from cutting can all promote local dendrite growth, leading to drastically decreased cycling stability of the demonstrated Zn metal batteries and K metal batteries. Polishing the metal electrodes on both sides and edges is shown to be effective to improve the electrochemical homogeneity of the metal anode and extend the cycling lifespan by over 700% in the demonstrated Zn metal cells. Finally, we demonstrate a simple and rapid surface passivation strategy that drastically increases the tolerance of such defects in Zn metal batteries. Also, we proposed a scalable, easily automated, and facile metallic K manufacturing with robust performance in K metal batteries.Since such imperfections are ubiquitous in commercially available metal foil products. Our results remind researchers about the significant detrimental effects of these very common defects introduced by metal manufacturing and processing, which should be taken into consideration evaluating metal battery performances. Furthermore, we call for research efforts to develop effective strategies that are scalable, easily automated, and cost-effective to increase the tolerance of batteries over such defects, which will be very important for large-scale, cost-effect energy storage hubs.References Pan He and Jiaxing Huang. "Detrimental effects of surface imperfections and unpolished edges on the cycling stability of a zinc foil anode." ACS Energy Letters, 2021,6,1990-1995.Pan He and Jiaxing Huang. "Chemical passivation stabilizes Zn anode." Advanced Materials, 2022, 34, 2109872.Pan He and Yang Xu. "Facile manufacturing potassium metal anode with robust performance". In preparation. Figure 1

Electrochemical Signatures of Potassium Plating and Stripping

Alkali metals are attractive anodes for high energy density batteries, but practical utilization of these materials in rechargeable cells has so far been hindered by safety concerns, limited Coulombic efficiencies and short cycle lives. These issues are all connected to the uneven electrodeposition and stripping of alkali metals; dendritic metal deposits can short circuit the cell and deposits with large surface areas consume more electrolyte and active material in side reactions.[1] To circumvent these problems, one of the approaches which have been attempted is electrolyte engineering. For instance, electrolytes with higher salt concentration, so called highly concentrated electrolytes, have been shown to suppress both dendrite growth and increase the Coulombic efficiency of metal anodes.[2,3] When different metal anode stabilization strategies are evaluated, it is common to perform galvanostatic cycling experiments in symmetric or asymmetric cells. This allows the cycling stability and Coulombic efficiency of the plating/stripping to be analyzed. Additionally, it is common to use features of the voltage profile as signatures on the mechanisms responsible for changes in electrochemical performance. For instance, a sharp decrease in (over)voltage during plating/stripping is a sign of a short circuit. A gradually increasing overvoltage during cycling on the other hand can be a result of continuous solid electrolyte interphase (SEI) buildup. However, several processes often occur in parallel when symmetric/asymmetric cells are cycled galvanostatically, each giving different contributions to the voltage profile which need to be deconvoluted to make sense of the data. In this contribution, we use three-electrode cells in combination with simple electrochemical experiments like cyclic voltammetry, chronoamperometry and chronopotentiometry to disentangle the contributions to different features in the galvanostatic voltage profiles of alkali metal anodes.In particular, we dissect the voltage profiles of potassium-copper (K-Cu) cells with highly concentrated electrolytes. Due to the higher reactivity of K compared to other alkali metals, certain features in the voltage profiles of these cells become exaggerated compared to lithium or sodium metal cells. We show that during galvanostatic deposition on a fresh Cu substrate, SEI formation and nucleation occur partly in parallel. If an SEI-formation step is performed prior to the galvanostatic deposition, a much sharper ‘nucleation peak’ in the voltage profile can be observed, indicative of the higher rate of nucleation that needs to occur in this case. Further, the potassium metal anode exhibits a steplike voltage profile from the second cycle and onwards. We confirm that this feature arises because bulk K is covered by a resistive native layer, whereas another type of, less resistive, interphase covers the freshly deposited K. This inhomogeneous interphase will inevitably promote preferential and inhomogeneous plating/stripping.

Design and Synthesis of Cubic K3-2 x Bax SbSe4 Solid Electrolytes for K-O2 Batteries.

Developing K-ion conducting solid-state electrolytes (SSEs) plays a critical role in the safe implementation of potassium batteries. In this work, a chalcogenide-based potassium ion SSE is reported, K3 SbSe4 , which adopts a trigonal structure at room temperature. Single-crystal structural analysis reveals a trigonal-to-cubic phase transition at the low temperature of 50 °C, which is the lowest among similar compounds and thus provides easy access to the cubic phase. The substitution of barium for potassium in K3 SbSe4 leads to the creation of potassium vacancies, expansion of lattice parameters, and a transformation from a trigonal phase to a cubic phase. As a result, the maximum conductivity of K3-2 x Bax SbSe4 reaches around 0.1 mS cm-1 at 40 °C for K2.2 Ba0.4 SbSe4 , which is over two orders of magnitude higher than that of undoped K3 SbSe4 . This novel SSE is successfully employed in a K-O2 battery operating at room temperature where a polymer-laminated K2.2 Ba0.4 SbSe4 pellet serves as a separator between the oxygen cathode and the potassium metal anode. Effective protection of the K metal anode against corrosion caused by O2 is demonstrated.

Dendrite-free and gasless potassium metal anodes assisted by the mechanical-electrochemical enhancing solid K-electrode and electrolyte interface

With their high-energy density and low-price advantage, potassium (K) metal batteries have been considered the next generation of energy storage system. However, applications of K metal anode are always obstructed by severe side reactions and rapid growth of K dendrites upon cycles due to the fragile solid electrolyte interface (SEI). Herein, a novel mechanical-electrochemical stability enhancement interface is constructed through potassium salt anion structure design and in-situ ion exchange reaction, which enables SEI with reducing side reactions and relieving interface stress during cycling process. The batteries with the designed SEI could deliver excellent performances with a high average Coulombic Efficiency of 95.91 %, a critical current density of 7.5 mA cm−2 and a durable stability of more than 1350 h (0.1 mA cm−2). This work provides an effective strategy to construct a high-energy and stable K metal anode interface and will inspire the electrolyte design for other alkali metal batteries.

High-Performance K Metal Batteries Enabled by Regulating an Electrolyte Solvation Structure

Batteries using a potassium metal (K-metal) anode are attention to a new type of low-cost and high-energy storage devices. However, the thermodynamic instability of the K-metal anode in organic electrolyte solutions causes uncontrolled growth of dendrites and parasitic reactions, which leads rapid capacity loss and low Coulombic efficiency.[1-4] In this presentation, I will introduce the advanced electrolyte using dual-salt for regulated solvation chemistry showing an improved the K-metal anode stability. Experimental and theoretical studies supported the details of solvation chemistry and results. Incorporating dual-salt into the electrolyte solution decreased the number of free solvent molecules surrounding the K+ leading to facile K+ desolvation as well as lowering the exchange current density improving the uniform K electrodeposition. Moreover, the modified electrolyte mitigates decomposition of the solvent molecules and leads to form enhanced mechanical rigidity of the SEI layer on the surface of the K–metal electrode with larger fraction of KF compound. Compared to previous studies, the K-metal anode using modified electrolyte shows long cycling stability at fast charge-discharge capability in symmetrical K | K cells. Even under high current density, the modified electrolyte ensures high areal capacity and an unprecedented lifespan with stable Coulombic efficiency for the K-metal full battery employing a sulfurized polyacrylonitrile cathode. M. Park, Y. Jeong, M. H. Alfaruqi, Y. Liu, X. Xu, S. Xiong, M.–G. Jung, H.–G. Jung, J. Kim, J.–Y. Hwang, Y.–K. Sun. Stable Solid Electrolyte Interphase for Long–Life Potassium Metal Batteries, ACS Energy Lett. 7 (2022) 401–409.Kim, W. Song, D.–Y. Son, L. K. One, Y. Qi. Lithium–Ion Batteries: Outlook on Present, Future, and Hybridized Technologies. J. Mater. Chem. A 7 (2019) 2942–2964.–H. Kim, G.–T. Park, B.–K. Son, G. W. Nam, J. Liu, L.–Y. Kuo, P. Kaghazchi, C. S. Yoon, Y.–K. Sun. Heuristic Solution for Achieving Long–Term Cycle Stability for Ni–Rich Layered Cathodes at Full Depth of Discharge, Nat. Energy 5 (2020) 860.–Y. Hwang, S.–T. Myung, Y.–K. Sun. Recent Progress in Rechargeable Potassim Batteries, Adv. Funct. Mater. 28 (2018) 1802938.

Effects of fluoroethylene carbonate additive on potassium metal anode

Effects of fluoroethylene carbonate additive on potassium metal anode

Toward the Formation of the Solid Electrolyte Interphase on Alkaline Metal Anodes: Ab Initio Simulations**

AbstractThe transition from lithium‐based energy storage to post lithium systems plays a crucial part in achieving an environmentally sustainable energy infrastructure. Prime candidates for the replacement of lithium are sodium and potassium batteries. Despite being critical to battery performance, the solid electrolyte interphase (SEI) formation process for Na and K batteries remains insufficiently understood, especially compared to the well‐established lithium systems. Using ab initio molecular dynamics (AIMD) simulations based on density functional theory (DFT) calculations, we study the first steps of SEI formation upon the decomposition of typical solvent molecules on lithium, sodium and potassium metal anodes. We find that two dominant products form during the early SEI formation of cyclical carbonates on alkali metal anodes, carbon monoxide and alkali‐carbonate. The carbonate‐producing reaction is thermodynamically favorable for all tested metals, however, Na and K exhibit a much stronger selectivity than Li towards carbonate formation. Furthermore, we propose a previously unknown reaction mechanism for the CO polymerization on metallic lithium.

Dendrite-free potassium metal anode induced by in-situ phase transitions of MoS2

Potassium ion batteries (PIBs) are identified as an imperative alternative for next-generation energy storage devices due to its abundant reserves. Even potassium (K) metal is a promising anode for its high theoretical capacity and intrinsic low potential, however, it still suffers from uncontrollable dendrite growth. Herein, a dendrite-free K anode is obtained by plating K metal on MoS2-modified carbon cloth (MoS2/CC@K). Specifically, MoS2 undergoes a series of phase transitions from initial MoS2 to KxMoS2 and final K2S4 with gradual insertion of K, then K metal is uniformly deposited on K2S4 with further discharging. This phase transition significantly reduces the K nucleation energy barrier. The strong interaction between K and K2S4 interface induces K in uniformly depositing to suppress the formation of K dendrites. Owing to these merits, the symmetric MoS2/CC@K cells exhibit low voltage hysteresis and superior cycling stability. When paired with perylene-3,4,9,10-tetracarboxylic diimide (PTCDI) cathode, the full cells display superior rate capability and long lifespan (10,000 cycles). Additionally, this strategy is also performed on Li and Na metal anodes, the MoS2/CC substrate still expresses superior electrochemical performance. This work provides a new view to induce the uniformly deposition of K, Li and Na metals.

Highly Stable Potassium Metal Anodes with Controllable Thickness and Area Capacity.

K metal battery is a kind of high-energy-density storage device with economic advantages. However, due to the dendrite growth and difficult processing characteristics, it is difficult to prepare stable K metal anode with thin thickness and fixed area capacity, which severely limits its development. In this work, a multi-functional 3D skeleton (rGCA) is synthesized by simple vacuum filtration and thermal reduction, and K metal anodes with controllable thickness and area capacity (K content) can be fabricated by changing the raw material mass and graphene layer spacing of rGCA. Moreover, the graphene sheet layer of rGCA can relax stress and relieve volume expansion; carbon nanotubes can serve as the fast transport channel of electrons, reducing internal impedance and local current density; Ag nanoparticles can induce the uniform nucleation and deposition of K+ . The K metal composite anodes (rGCA-K) based on the conductive skeleton can effectively suppress dendrites and exhibit excellent electrochemical performance in symmetric and full cells. The controllable fabrication process of stable K metal anode is expected to help K metal batteries move toward the stage of commercial production.

Regulating the Solvation Structure of Electrolyte via Dual–Salt Combination for Stable Potassium Metal Batteries

Batteries using potassium metal (K-metal) anode are considered a new type of low-cost and high-energy storage device. However, the thermodynamic instability of the K-metal anode in organic electrolyte solutions causes uncontrolled dendritic growth and parasitic reactions, leading to rapid capacity loss and low Coulombic efficiency of K-metal batteries. Herein, an advanced electrolyte comprising 1M potassium bis(fluorosulfonyl)imide (KFSI) + 0.05M potassium hexafluorophosphate (KPF6 ) dissolved in dimethoxyethane (DME) is introduced as a simple and effective strategy of regulated solvation chemistry, showing an enhanced interfacial stability of the K-metal anode. Incorporating 0.05M KPF6 into the 1M KFSI in DME electrolyte solution decreases the number of solvent molecules surrounding the K ion and simultaneously leads to facile K+ de-solvation. During the electrodeposition process, these unique features can lower the exchange current density between the electrolyte and K-metal anode, thereby improving the uniformity of K electrodeposition, as well as potentially suppressing dendritic growth. Even under a high current density of 4mA cm-2 , the K-metal anode in 0.05M KPF6 -containing electrolyte ensures high areal capacity and an unprecedented lifespan with stable Coulombic efficiency in both symmetrical half-cells and full-cells employing a sulfurized polyacrylonitrile cathode.

A host potassiophilicity strategy for unprecedentedly stable and safe K metal batteries.

Creating high-performance host materials for potassium (K) metal anodes remains a significant challenge due to the complex preparation process and poor K reversibility. In our work, we developed a potassiophilicity strategy using an oxygen-modified carbon cloth (O-CC) network as a host for K metal anodes. The O-CC network exhibited superior potassiophilic ability, and this improvement was also observed in other carbon hosts using the same process. The oxygen-induced epoxy group in the carbon network regulates interface electrons and enables strong binding of K adatoms through orbital hybridization, resulting in fewer side reactions with the electrolyte and promoting K-ion desolvation and uniform deposition. These factors result in unprecedented stability of the carbon network host, with a long lifespan of over 5500 hours at 0.5 mA cm-2/0.5 mA h cm-2 and 3500 h at 1 mA cm-2/0.5 mA h cm-2 in symmetric cells for K metal anodes, surpassing the cycle life of all previously reported K metal anodes. Furthermore, a high average coulombic efficiency of over 99.3% is demonstrated in O-CC//K cells during 210 cycles. The O-CC also exhibited a stable electrochemical performance, with a capacity retention of 73.3% in full cells coupled with a perylene-3,4,9,10-tetracarboxylic dianhydride cathode. We believe that this new strategy holds great promise for metal anodes in battery applications.