Li Metal Research Articles

An artificial layer enables in situ generation of a homogeneous inorganic/organic composite solid electrolyte interphase for stable lithium metal batteries.

Lithium (Li) metal anodes are considered one of the most promising anodes for high-performance batteries with ultra-high specific energy density. However, uncontrolled dendrite growth and the unsuitability of common systems for high voltage hinder the development of Li metal batteries with long cycle life. Herein, we report a rationally designed artificial solid electrolyte interphase (SEI) for Li metal anodes, incorporating LiNO3 and lithium difluoro(oxalato)borate (LiDFOB) as additives within a porous poly (vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) polymer skeleton (referred to as PNF). LiNO3 and LiDFOB can release and synergistically react at the electrode surface, leading to the in situ generation of a homogeneously distributed inorganic/organic SEI during the electrochemical process. This SEI improves homogeneity, ionic conductivity and mechanical stability, contributing to the suppression of electrolyte side reactions and Li dendrite growth. Moreover, a uniform CEI with high Li+ conductivity can be constructed on the NCM811 particles, further enhancing the structural integrity of the NCM811 cathode. As a result, the artificial SEI layer on Li metal anodes enables stable cycling of Li-Cu half cells in an ester-based electrolyte and Li-LiNi0.8Mn0.1Co0.1O2 full cell even at a high voltage of 4.5 V. This work provides new insights into designing homogeneous SEIs for Li metal batteries.

In Situ Forming Asymmetric Gel Polymer Electrolyte Enhances the Performance of High-Voltage Lithium Metal Batteries.

With the rapid evolution of electric vehicle technology, concerns regarding range anxiety and safety have become increasingly pronounced. Battery systems with high specific energy and enhanced security, featuring ternary cathodes paired with lithium (Li) metal anodes, are poised to emerge as next-generation electrochemical devices. However, the asymmetric configuration of the battery structure, characterized by the robust oxidative behavior of the ternary cathodes juxtaposed with the vigorous reductive activity of the Li metal anodes, imposes elevated requisites for the electrolytes. Herein, a well-designed gel polymer electrolyte with asymmetric structure was successfully prepared based on the Ritter reaction of cyanoethyl poly(vinyl alcohol) (PVA-CN) and cationic ring-opening polymerization of s-Trioxane. With the aid of the sieving effect of separator, the in situ asymmetric gel polymer electrolyte has good compatibility with both the high-voltage cathodes and Li anodes. The amide groups generated by PVA-CN after the Ritter reaction and additional cyano groups can tolerate high voltages up to 5.1 V, matching with ternary cathodes without any challenges. The functional amide and cyano groups participate in the formation of the cathode electrolyte interface and stabilize the cathode structure. Meanwhile, the in situ formed ether-based polyformaldehyde electrolyte is beneficial for promoting uniform Li deposition on anode surfaces. Li-Li symmetric cells demonstrate sustained stability over 2000 h of cycling at a current density of 1 mA cm-2 for 1 mAh cm-2. Furthermore, the capacity retention rate of Li(Ni0.6Mn0.2Co0.2)O2-Li cells with 0.5 C cycling after 300 cycles is 92.2%, demonstrating excellent cycle stability. The electrolyte preparation strategy provides a strategy for the progress of high-performance electrolytes and promotes the rapid development of high-energy-density Li metal batteries.

Wet Chemical Method ZnF2 Interlayer for High Critical Current Density Lithium Metal Batteries Utilizing Ba and Ta–Doped Li7La3Zr2O12 Garnet Solid Electrolyte

AbstractLi metal batteries with garnet‐type solid electrolytes have the potential to increase specific energy and power densities of current Li‐ion batteries. Li metal batteries have been hampered by the poor wettability of solid electrolyte with elemental lithium. Here, to resolve the solid garnet electrolyte/Li interface issue, a scalable, cost‐effective, and efficient surfactant‐assisted wet‐chemical strategy is developed. A ZnF2 interlayer coating is applied on Ba and Ta ‐co‐doped Li7La2.75Ba0.25Zr1.75Ta0.25O12 that formed LiF and Li‐Zn alloy upon contact with molten Li. Conformal contact applying a homogenous surfactant‐assisted ZnF2 coating reduced the interfacial resistance from 87 to 15.5 Ω cm2 which enhanced critical current density to a record high value of 5 mA cm−2 at room temperature. Dense and Li2CO3 free garnet solid electrolyte assisted in achieving long‐term stability for 1000 cycles at 1 mA cm−2. Interface stabilized Li/ZnF2‐ solid electrolyte/liquid electrolyte/LiFePO4 cell displayed a 90% capacity retention over 800 cycles at 0.2 C, with Coulombic efficiency of 99% as well as excellent cycle stability at 1 C, with ≈91% of capacity retention for 500 cycles. Using a new design principle for Li anode interfaces, next‐generation power‐intensive and stable solid‐state Li metal batteries can be developed.

A biomass-based protective layer with rigid structure and ion conductivity for high-performance lithium metal batteries

Lithium (Li) metal has been considered as an effective anode material because of its high theoretical capacity, but the uncontrolled dendrite growth and the unstable electrode/electrolyte interface limit its practical application. In this work, proanthocyanidin (PA), a natural extracted biomass, was designed and developed as a coating material to guide homogeneous deposition and restrain side reaction for lithium metal batteries. The rigid benzene ring structure of PA can increase the mechanical strength to restrain dendrite growth on Li surface. Moreover, the spontaneous formation of organolithium (PA-Li) structure from the reaction of phenolic hydroxyl group with Li metal increase the ion transportation ability of PA layer and induce the uniform deposition of Li+ ions to hinder the growth of Li dendrites, as well as prevent the direct contact of organic electrolyte with Li metal to suppress the interface side reaction. As a result, Li metal anode with PA-Li exhibits stable cycling properties for 2800 h at 2 mA cm-2 and 2 mAh cm-2, better that of bare Li (200 h). Li-sulfur full battery with PA-Li can still achieve a capacity of 570 mAh g-1 after 300 cycles. This work provides an effective strategy for the construction a natural functional layer on Li surface to enhance the electrochemical performance, as well as the implementation of high-value utilization for natural biomass.

Regulating interfacial reactions via quasi-solid polymer electrolyte to enable high-voltage lithium metal batteries

Sulfolane (SUL), known for its low cost, environmental friendliness, and high voltage tolerance, stands out as a promising polar solvent for lithium (Li) metal batteries with high energy density. However, its long-term stability with Li metal is compromised due to its inherently low reduction resistance. To address this issue, we introduce a novel electrolyte strategy, where the reactive SUL is encapsulated within a fluorinated polymer framework formed through in-situ thermal polymerization. The polymer network’s specific structure interacts with SUL, effectively mitigating its electrochemical degradation on the Li metal anode and the NCM811 cathode, thus enhancing electrode stability. This approach not only extends the Li+ plating/stripping reversibility for over 1,000 h at a current density of 0.3 mA cm−2, but also delivers outstanding performance in NCM811||Li batteries, achieving a capacity retention of 78.56 % after 1,000 cycles at 30 °C and 87.14 % after 100 cycles at 60 °C under a high cutoff voltage of 4.5 V.

Bilayer Interphase for Air-Stable and Dendrite-Free Lithium Metal Anode Cycling in Carbonate Electrolytes.

The intrinsic reactivity of lithium (Li) toward ambient air, combined with insufficient cycling stability in conventional electrolytes, hinders the practical adoption of Li metal anodes in rechargeable batteries. Here, a bilayer interphase for Li metal is introduced to address both its susceptibility to corrosion in ambient air and its deterioration during cycling in carbonate electrolytes. Initially, the Li metal anode is coated with a conformal bottom layer of polysiloxane bearing methacrylate, followed by further grafting with poly(vinyl ethylene carbonate) (PVEC) to enhance anti-corrosion capability and electrochemical stability. In contrast to single-layer applications of polysiloxane or PVEC, the bilayer design offers a highly uniform coating that effectively resists humid air and prevents dendritic Li growth. Consequently, it demonstrates stable plating/stripping behavior with only a marginal increase in overpotential over 200 cycles in carbonate electrolytes, even after exposure to ambient air with 46% relative humidity. The design concept paves the way for scalable production of high-voltage, long-cycling Li metal batteries.

Lithiophilic Protective Dual Layer Enabling Stable Electrodeposition of Lithium at High Current Density

Lithium (Li) is an ideal anode material for rechargeable batteries and thus manufacturing Li metal is crucial for the practical development of Li metal batteries. Electrodeposition is an efficient technique for producing ultrathin and scalable Li metal electrodes. However, the dendritic growth and the side reactions of Li with electrolyte during the electrodeposition are the main obstacles to overcome. In this study, we designed a pre-coated protective dual layer (PDL) composed of a poly(ethylene oxide)-based solid polymer electrolyte (SPE) and a polydopamine-coated cellulose membrane (PD-CM). The adhesive and ion-conductive SPE layer suppressed the growth of Li dendrites and side reactions with liquid electrolyte. The PD-CM layer with high porosity and lithiophilicity promoted a facile and uniform Li-ion flux. By applying the pre-coated PDL, Li was uniformly electrodeposited on the Ag-coated Cu at a high current density of 6 mA cm−2. The Li/LiFePO4 cell composed of an electrodeposited Li anode with PDL and a LiFePO4 cathode was assembled without an additional separator, and its cycling performance was evaluated. The cell initially delivered a high discharge capacity of 154.8 mAh g−1 at 45 °C and exhibited excellent cycling stability with a capacity retention of 97.0% after 200 cycles.

Comment on 'A PET reconstruction formulation that enforces non-negativity in projection space for bias reduction in Y-90 imaging'.

We read with great interest the paper by Limet al(2018Phys. Med. Biol.63035042) on bias reduction in Y-90 PET imaging. In particular, they proposed a new formulation of the tomographic reconstruction problem that enforces non-negativity in projection space as opposed to image space. We comment on the algorithm they derived from this formulation and bring some clarifications on the constraint that this algorithm respects.

Unveiling the Reaction Mystery Between Lithium Polysulfides and Lithium Metal Anode in Lithium-Sulfur Batteries.

Lithium-sulfur (Li-S) batteries are widely regarded as one of the most promising next-generation high-energy-density energy storage devices. However, soluble lithium polysulfides (LiPSs) corrode Li metal and deteriorate the cycling stability of Li-S batteries. Understanding the reaction mechanism between LiPSs and Li metal anode is imperative. Herein, the reaction rate and products of LiPSs with Li metal anode, the composition and structure of the as-generated solid electrolyte interphase (SEI), and the mechanism of lithium nitrate (LiNO3) additives for inhibiting the corrosion reactions are systematically unveiled. Concretely, LiPSs react with Li metal anode more rapidly than Li salt and generate a Li2S-rich SEI. The Li2S-rich SEI is highly reactive with LiPSs, which exacerbates the formation of dendritic Li and the continuous corrosion of active Li. LiNO3 functions dominantly by modulating the solvation structure of LiPSs and inherently reducing the reactivity of LiPSs, rather than the conventional understanding of LiNO3 participating in the formation of SEI. This work reveals the reaction mechanism between LiPSs and Li metal anode and inspires rational regulating of the solvation structure of LiPSs for stabilizing Li metal anode in Li-S batteries.

Hybrid conductive-lithophilic-fluoride triple protection interface engineering: Dendrite-free reverse lithium deposition for high-performance lithium metal batteries

Lithium metal batteries (LMBs) with high energy density are impeded by the instability of solid electrolyte interface (SEI) and the uncontrolled growth of lithium (Li) dendrite. To mitigate these challenges, optimizing the SEI structure and Li deposition behavior is the key to stable LMBs. This study novelty proposes a facile synthesis of MgF2/carbon (C) nanocomposite through the mechanochemical reaction between metallic Mg and polytetrafluoroethylene (PTFE) powders, and its modified polypropylene (PP) separator enhances LMB performance. The in-situ formed highly conductive fluorine-doped C species play a crucial role in facilitating ion/electron transport, thereby accelerating electrochemical kinetics and altering Li deposition direction. During cycling, the in-situ reaction between MgF2 and Li leads to the formation of LiMg alloy, along with a LiF-rich SEI layer, which reduces the nucleation overpotential and reinforces the interphase strength, leading to homogeneous Li deposition with dendrite-free feature. Benefiting from these merits, the Li metal is densely and uniformly deposited on the MgF2/C@PP separator side rather than on the current collector side. Furthermore, the symmetric cell with MgF2/C@PP exhibits superb Li plating/stripping performance over 2800 h at 1 mA cm−2 and 2 mA h cm−2. More importantly, the assembled Li@MgF2/C@PP|LiFePO4 full cell with a low negative/positive ratio of 3.6 delivers an impressive cyclability with 82.7% capacity retention over 1400 cycles at 1 C.

Dielectric additive induced weak Li solvation towards stabilized solid electrolyte interface for 4.6V lithium metal batteries

Developing stable electrode-electrolyte interphases on Li metal anode (LMA) and high voltage cathode is crucial for producing durable Li metal batteries. Electrolyte engineering has been regarded as an efficient way to in-situ construct stable and robust interphase. Herein, a dielectric electrolyte system is proposed by introducing LiNbO3 nanoparticles to liquid carbonate-based electrolyte for regulating Li+ solvation structure, and thus inducing stable inorganic-rich solid electrolyte interphase. Moreover, these dielectric nano LiNbO3 additives can regulate the Li+ flux through their build-in electric field to guide dendrite free Li deposition. These multi-functional features of LiNbO3 allow for exceptional cyclic performance in both symmetric cell configuration (3300 h at 0.5 mA cm−2 and 1 mA h cm−2) and Li||LiNi0.8Co0.1Mn0.1O2 half-cell charged at 4.6 V with capacity retention of 80% over 200 cycles. These results demonstrate great potential of dielectric electrolyte on improving the performance of lithium metal batteries.

Dual-Interphase-Stabilizing Sulfolane-Based Electrolytes for High-Voltage and High-Safety Lithium Metal Batteries.

High-voltage Li metal battery (HV-LMB) is one of the most promising energy storage technologies to achieve ultrahigh energy density. Nevertheless, electrolytes reported to date are difficult to simultaneously stabilize the Li metal anode and high-voltage cathode, especially without the assistance of expensive and corrosive high-concentration Li salts. Herein, a dual-interphase-stabilizing (DIS) and safe electrolyte that bypasses the high-concentration Li salt is reported. The electrolyte consists of high-flash-point sulfolane as solvent, molecular-orbital-engineered additives that enable stable B-F rich cathodic interphase, and unique C-F rich organic anodic interphase. The stable cycling of both Li metal anode and 4.75V-LiCoO2 cathode in the DIS electrolyte (> 500 cycles) is demonstrated. HV-LMB pouch cells of a high energy density (435Wh kg-1) can sustainably operate for more than 100 cycles. Moreover, the low cost and high thermal stability of the DIS electrolyte offer superior cost-effectiveness and safety for large-scale applications of HV-LMBs in the future.

Tin-based dual-modification enabling enhanced air stability and electrochemical performance for Li5.5PS4.5Cl1.5 in all-solid-state lithium metal batteries

As one of sulfide electrolytes, chlorine-rich lithium argyrodites (Li5.5PS4.5Cl1.5) have significant advantages as solid state electrolytes (SSEs) in all-solid-state batteries (ASSBs) due to their ultra-high conductivity. However, their practical application is limited by poor air stability and weak compatibility with Li metals. Herein, we enhance the performance of Li5.5PS4.5Cl1.5 by doping it with SnO2, resulting in the formation of the Li5.58P0.92Sn0.08S4.34O0.16Cl1.5 electrolyte. The introduction of Sn and O dopants forms strong Sn-S and P-O bonds in the electrolyte, replacing the sensitive P-S bonds and suppressing H2S release. Additionally, this doped electrolyte demonstrates an impressive Li-ion conductivity of 5.71 mS cm−1, a high critical current density of 2.9 mA cm−2, and significantly improved air and moisture stability. Moreover, the Sn dopant produces a Li-Sn alloy layer on the bare Li metal anode, endowing the ASSB with an initial discharge capacity of 146.7mAh/g at 0.2C and a capacity retention of 86.2 % after 200 cycles at 0.5C. Combining with a 10 wt% SnF2-treated Li metal anode to further strengthen the electrode interfacial stability by the in-situ formed Li-Sn and LiF derivatives, the resultant full cell delivers a promoted initial discharge capacity of 179.5mAh/g at 0.2C and a high discharge capacity of 112.2mAh/g after 300 cycles at 0.5C. The dual strategy of electrolyte doping and Li anode modification achieves a synergistic effect that enables the ASSB to exhibit superior electrochemical performance, providing an effective way of preparing stable sulfide-based SSEs for large-scale applications.

Decoupling the roles of grain boundary strength and grain size hidden in grain-level electro-chemo-mechanical failure of solid-state electrolyte

Garnet lithium lanthanum zirconium oxide (Li7La3Zr2O12, LLZO) is a benchmark solid-state electrolyte material receiving considerable attention owing to its high conductivity and chemical stability against Li metal. Although its electro-chemo-mechanical failure mechanisms have been much investigated, the equivocal roles of grain boundary strength and grain size of LLZO remain under-explored, hindering further performance improvements. Here we decoupled the effects of grain size and grain boundary strength of polycrystalline LLZO via the combination of electrochemical kinetics and the cohesive zone model. We discovered that the disintegration of LLZO is initiated by the accumulation of local displacements, which strongly relates to the changes in both grain size and grain boundary strength. However, variations in grain boundary strength affect the diffusion and propagation pathways of damage, while the failure of LLZO is determined by the grain size. Large LLZO grains facilitate transgranular damage under low grain boundary strength, which can alter local chemo-mechanics within the bulk of LLZO, leading to more extensive damage propagation. The results showcase the structure optimization pathways by preferentially controlling the growth of lithium dendrites at grain boundaries and their penetration in garnet-type SSE.

In-situ construction of an alloy hybrid interface and ultrathin ZnS nanosheets catalyst for polysulfide by trifunctional ZnI2 electrolyte additive for Li-S batteries

Lithium-sulfur batteries (LSBs) are considered promising candidates for next-generation energy storage devices owing to their ultrahigh theoretical energy density. However, LSBs are hindered by uncontrollable lithium dendrite growth, polysulfides shuttle effects, and sluggish sulfur kinetics. Herein, this work develops a multifunctional ZnI2 electrolyte additive for LSB for local high concentration base electrolyte. At anode side, a LixZn alloy hybrid interface leading to planar deposited lithium is formed from the reaction between Li metal and the ZnI2 additive and reduction products of Li+ solvation shell of the electrolyte. Moreover, planar deposited lithium was confirmed by in-situ liquid transmission electron microscopy (TEM). For cathode side, Zn2+ under the drive of electric field prior react with lithium polysulfide to form ultrathin ZnS nanosheets exposed with (100) miller index serving as a catalyst to accelerate sulfur redox kinetics and inhibit polysulfides shuttling. Consequently, the LSB with ZnI2 additive exhibits a remarkable discharge capacity of 712 mA h g−1 at 0.5 C after 300 cycles and a superior rate capability of 674.9 mA h g−1 at 2 C. This work demonstrates that ZnI2 serves as a multifunctional electrolyte additive to simultaneously facilitate the sulfur redox kinetics, reduce the shuttle effect, and promote smooth Li growth.

A modified separator based on ternary mixed-oxide for stable lithium metal batteries

Li metal batteries (LMBs) are among the most promising options for next-generation secondary batteries under the rapidly growing demand for high-energy–density electrochemical energy storage. However, the implementation of LMBs are hindered by major obstacles such as dentritic Li deposition and low cycling Coulombic efficiency. A practical functional separator is developed in this study, which consists of a Lewis acidic mixed oxide of ZrO2-SiO2-Al2O3 as a functional coating with anion anchoring ability to modulate ion transport in the vicinity of the Li metal anode, delivering a high Li+ transference number of 0.88 in carbonate electrolytes that suppresses dendrite formation. The strong Lewis acid sites in ZrO2-SiO2-Al2O3 originate from coordinatively unsaturated Zr4+ ions, which immobilize anions and reduce their decomposition rate. This significantly improves the chemical stability of the electrolyte and induces a more stable solid electrolyte interphase layer. The modified separator enables an anode-free cell containing a high-loading LiNi0.8Co0.1Mn0.1O2 cathode to present stable charge and discharge cycling for 150 cycles at 0.5C. By effectively suppressing Li dendrite growth and supporting the long-term operation of anode-free LMBs, this study offers a novel approach to rationally design mixed oxides with high Lewis acidity for functional separators.

Wide-temperature and high-voltage Li||LiCoO2 cells enabled by a nonflammable partially-fluorinated electrolyte with fine-tuning solvation structure

Efficient, safe, and reliable energy output from high-energy-density lithium metal batteries (LMBs) at all climates is crucial for portable electronic devices operating in complex environments. The performance of corresponding cathodes and lithium (Li) metal anodes, however, faces significant challenges under such demanding conditions. Herein, a nonflammable electrolyte for high-voltage Li||LCO cells has been designed, including partially-fluorinated ethyl 4,4,4-trifluorobutyrate (ETFB) as the key solvent, guided by theoretical calculations. With this ETFB-based electrolyte, Li||LCO cells exhibit enhanced reversible capacities and superior capacity retention at an elevated charge voltage of 4.5 V and a wide operating temperature range spanning from −60 °C to 70 °C. The cells achieve 67.1% discharge capacity at −60 °C, relative to room temperature capacity, and 85.9% 100th-cycle retention at 70 °C. The outstanding properties are attributed to the LiF-rich interphases formed in the ETFB-based electrolyte with a fine-tuned solvation structure, in which the coordination environment in the vicinity of Li+ cations and the distance between anion and solvents are subtly adjusted by introducing ETFB. This solvation structure has been mutually elucidated through joint spectra characterizations and atomistic simulations. This work presents a new strategy for the design of electrolytes to achieve all-climate reliable and safe application of LMBs.

Li2CO3/LiF-Rich Solid Electrolyte Interface Stabilized Lithium Metal Anodes for Durable Li-CO2 Batteries

Lithium carbon dioxide (Li-CO2) batteries are considered a promising next-generation energy storage device due to their high theoretical energy density and potential carbon neutralization. Despite numerous iterative advancements in cathode catalysts for Li-CO2 batteries, the cycling stability still to be hindered by the growth of lithium dendrites during cycling, primarily due to uneven deposition and the side reaction of sufficient CO2 with the Li metal anode. In this work, bisalt electrolyte (BE) consisting of LiPF6 and LiTFSI is used as a localized anode surface stabilizer to achieve durable Li-CO2 batteries. The introduction of PF6− promotes the decomposition and reduction of TFSI−, leading to the formation of LiF-rich inorganic SEI (Li2CO3/LiF-rich) with enhanced Li+ affinity and good electronic insulating properties. This effectively inhibits lithium dendrite formation while also insulating CO2 and electrolytes from contacting the lithium anode. Consequently, the Li symmetric battery incorporating the novel BE exhibits a long cycling life of 912 hours (∼3.8 times of the cell with a single-salt electrolyte (SE)). The BE based Li-CO2 battery achieves an ultra-long cyclelife of 2720 hours (∼2.6 times of SE battery) and outstanding rate capability. In addition, the assembled belt-shaped Li-CO2 batteries could stably power a digital watch for 1267 hours.

Tow-way regulation strategy for in-situ electropolymerization additives coordinated by double bonds and boric acid groups in lithium secondary batteries

The stability and cycle life of the cathode material directly affect the electrochemical performance of the secondary battery, and the dendrite problem of the anode material greatly destroys its safety. To solve the above problems, here we report a small organic molecule monomer, 2,2-dimethylvinylboronic acid (DEBA) containing carbon–carbon double bonds and boric acid groups as electrolyte additive for lithium secondary battery. The unsaturated carbon–carbon double bonds in DEBA can undergo in-situ electropolymerization during the electrochemical process, forming a polymer network. The electron-deficient boron element can easily combine with the electron-rich lithium salt anion to form a B-F bond. It can promote the transport rate of Li+, alleviate the Li+ concentration gradient at the interface, and achieve uniform and dense deposition on the Li metal surface. The Li//graphite and Li//LiFePO4 half-cell experiments show that DEBA has an excellent tow-way regulation effect. This rationally designed dual-functional electrolyte additive provides a broad prospect for future electrolyte engineering.

Ionic Covalent Organic Framework Solid-State Electrolytes.

Rechargeable secondary batteries, widely used in modern technology, are essential for mobile and consumer electronic devices and energy storage applications. Lithium (Li)-ion batteries are currently the most popular choice due to their decent energy density. However, the increasing demand for higher energy density has led to the development of Li metal batteries (LMBs). Despite their potential, the commonly used liquid electrolyte-based LMBs present serious safety concerns, such as dendrite growth and the risk of fire and explosion. To address these issues, using solid-state electrolytes in batteries has emerged as a promising solution. In this Perspective, recent advancements are discussed in ionic covalent organic framework (ICOFs)-based solid-state electrolytes, identify current challenges in the field, and propose future research directions. Highly crystalline ion conductors with polymeric versatility show promise as the next-generation solid-state electrolytes. Specifically, the use of anionic or cationic COFs is examined for Li-based batteries, highlight the high interfacial resistance caused by the intrinsic brittleness of crystalline ICOFs as the main limitation, and presents innovative ideas for developing all- and quasi-solid-state batteries using ICOF-based solid-state electrolytes. With these considerations and further developments, the potential for ICOFs is optimistic about enabling the realization of high-energy-density all-solid-state LMBs.