Carbon Binder Research Articles

Impact of Carbon Binder Domain on the Performance of Lithium-metal Batteries

Pseudo-2-dimensional models are routinely used to predict the lithiation curves for energy storage devices, including lithium-metal batteries. The performance of such models is as good as their parameterization, which remains a challenge especially in the presence of carbon binder domain (CBD). We propose two alternative parameterization strategies, which explicitly account for the CBD volume fraction and physical properties. The first aggregates CBD with the electrolyte-filled pore space and expresses the Bruggeman exponent in terms of a solution of microstructure-specific closure problem. The second treats CBD and active particles as a composite solid phase, whose effective properties are computed (semi-)analytically via homogenization. We show that the latter strategy used to parameterize the Doyle-Fuller-Newman model provides an attractive middle ground between the model complexity and the prediction accuracy. Our modeling results suggest that the battery discharge time decreases as either the CBD volume fraction increases or the CBD ionic diffusivity decreases, and is insensitive to the CBD ionic conductivity. The quantitative nature of these observations can be used in the optimal design of porous cathodes.

About the Consideration of the Inactive Materials and the Meshing Procedures in Computational Models of Lithium Ion Battery Electrodes

AbstractLithium‐ion batteries (LIBs) constitute a crucial technology in the ongoing energy transition. Still, the composite porous electrodes in LIBs remain complex systems which still need optimization to meet the requirements from the applications, e. g., high energy density for the automotive sector. To achieve well‐designed LIB electrodes, computational continuum modeling with three‐dimensional (3D) resolution constitutes a powerful tool to gain insights on the working principles of these electrodes. However, due to the complexity of the material properties and geometrical features within the electrodes, until mid‐2010’s such type of models had to make numerous assumptions, especially regarding the carbon additive and binder (all together standing for the so called inactive phase), that was not explicitly resolved in 3D. Recently, the battery modeling field has undergone tremendous progress which allowed the emergence of a new generation of models, more accurate and realistic than ever before. This review presents the latest developments through the prism of the consideration of the inactive phase in these models, and also provides recommendations on how to design modeling studies in order to minimize numerical errors originated by the meshing procedures of the materials and electrode volumes, a crucial step when a continuum model is set.

Low carbon binder preparation from slag-red mud activated by MSWI fly ash-carbide slag: Hydration characteristics and heavy metals' solidification behavior

Municipal solid waste incineration fly ash (MSWIFA) is hazardous, which safe disposal is a challenge. This study successfully prepared binder using MSWIFA and carbide slag (CS) as solid waste alkaline activators, stimulating the activity of red mud (RM) and ground granulated blast-furnace slag (GGBS). The properties and evolution mechanism of the binder were comprehensively evaluated in terms of compressive strength, fluidity, heavy metal leaching concentration, chloride ions' curing rate, and micromethods (XRD, SEM, EDS, and FTIR). The results show that CS and MSWIFA provide an alkaline environment for the hydration of RM and GGBS, promoting the formation of hydrated calcium chloroaluminate (HCC), ettringite, C-(A)-S-H gels and hydrotalcite (HT). At a mixing ratio CS: RM: GGBS: MSWIFA = 1:3:3:3, the binder had fluidity of 130 mm, 28 d compressive strength of 24.49 MPa and chloride curing rate over 80%. The environmental pH value mainly controlled the leaching risk of harmful components: its increase dropped the leaching rate of heavy metals. The addition of GGBS improved the structural compactness and buffering resistance of the matrix, effectively reducing the leaching risk of Cr and Zn heavy metals and keeping the leaching concentration of hazardous substances within the limits of national standards. This new binder system can be used to prepare pavement bricks and concrete blocks, mitigating solid waste environmental pressure and saving binder preparation costs.

Li-ion Electrode Microstructure Evolution during Drying and Calendering

The drying process of electrodes might seem to be a simple operation, but it has profound effects on the microstructure. Some unexpected changes can happen depending on the drying conditions. In prior work, we developed the multiphase-smoothed-particle (MPSP) model, which predicted a relative increase in the carbon additive and binder adjacent to the current collector during drying. This motivated us to undertake the present experimental investigation of the relationship between the drying rate and microstructure and transport properties for a typical anode and cathode. Specifically, the drying rate was controlled by means of temperature for both an NMC532 cathode and graphite anode. The material distribution was analyzed using a combination of cross-section SEM images and the energy-dispersive X-ray spectroscopy elemental maps. The binder concentration gradients were developed in both the in- and through-plane directions. The through-plane gradient is evident at a temperature higher than 150 °C, whereas the in-plane variations resulted at all drying temperatures. The measurements identified an optimum temperature (80 °C) that results in high electronic conductivity and low ionic resistivity due to a more uniform binder distribution. Trends in transport properties are not significantly altered by calendering, which highlights the importance of the drying rate itself on the assembled cell properties.

Crack width control and mechanical properties of low carbon engineered cementitious composites (ECC)

• An ECC with LC3 binder reinforced with polypropylene fiber designed for tight crack width (less than 50 µm at 1% tensile strain) has been developed. • Crumb rubber at 50% replacement level of fly ash was found to be optimal in balancing tight crack width and compressive strength loss. • Compared with PVA-ECC, the embodied carbon of the PP-ECC was reduced by 40–50%. Engineered Cementitious Composites (ECC) have superior properties with high tensile ductility and tight crack width compared to conventional concrete. The properties of ECC are significantly influenced by the material composition which can be tailored to enhance the sustainability of ECC. Towards this goal, recycled crumb rubber (CR) and silica fume (SF) were used to tailor the properties of a polypropylene-fiber reinforced ECC with a low carbon binder based on limestone calcined clay cement (LC3) in this study. Crumb rubber was found to be effective in enhancing strain-hardening performance and reducing the width of the multiple microcracks. However, a loss of compressive strength was accompanied by an increasing amount of CR. While silica fume or lower w/b ratio enhanced the compressive strength, the crack width of ECC increased at higher SF content or lower w/b. The underlying mechanisms of these trends were traced to the alteration of the matrix fracture toughness and fiber/matrix interfacial bond. Rubber particle bridging was found to contribute to crack width control. The combined use of the LC3 green binder and CR led to a lowering of the embodied and operational carbon footprint of ECC.

Blended Portland cement with high limestone loads modified with a waste glass based sodium silicate of different ratios SiO2/Na2O

This paper presents the results of one-part alternative low CO2 cements made of 60%limestone-30% portland cement ((LS-PC)m) and modified with 10% of a waste glass-based sodium silicate (SWG) synthesized by thermochemically processing blends of waste glass-NaOH of 3 different SiO2/Na2O ratios. The added alkali (from NaOH) contents in the (LS-PC)m was kept low, leading to under 2% Na2Oeq. The reaction products were characterized in pastes and the strength development in mortars. The addition of SWG and its SiO2/Na2O ratio had significative effects in the setting time, heat released, flowability, early and late mechanical strength, as well as in the reaction products formed. Lower alkali contents in the SWG did not drastically affect the flowability and setting time, also, the early strength was enhanced without impairing the late strength; in contrast, the opposite occurred for SWG with high alkali contents. The mortars reached acceptable 28-day strengths and similar 180-day strength as a reference Portland cement mortar. The results suggest that the SWG promoted the early formation of carboaluminates and C-S-H of different compositions, evidenced by the signals of six-fold coordinated Al and Q1, Q2(1Al) and Q2 sites, respectively, in the 27Al and 29Si RMN spectra. The studied binders could be a promising alternative, along with other low carbon binders, to contribute to reduce CO2 emissions.

Circular Manufacturing and Direct Recycling of Li-Ion Batteries Electrodes Via Solventless Melt Process

The expansion of the electric vehicles (EV) market demands new green fabrication methods of lithium-ion batteries (LIBs), a crucial component of EVs. At the same time, it provokes a dramatic increase of production scrap volume of LIBs with more and more EV batteries reaching end-of-life in the next years. LIBs are hazardous, posing chemical and fire risks, especially at their end-of-life. Considering their growing volume, disposal in landfill is no more an acceptable option. Furthermore, LIBs contain high-value materials (cobalt, nickel, lithium...), many of which are mined and produced via unsustainable or unethical supply chains. Thus, it becomes important to manufacture, salvage and recycle LIBs safely, responsibly and by minimizing production residues. Current recycling processes, namely pyrometallurgy and hydrometallurgy are complex, energy intensive and/or requiring large amounts of water and other chemicals for the separation of valuable elements and the preparation of new active materials.We have developed an inexpensive original melt solventless high-shear process for the manufacturing of Li-ion cathodes and anodes as well as the direct recycling of scrap electrodes and used electrodes. This process is adapted to a variety of electrodes morphologies and chemistries. This process consists in the following steps:- First, active filler dispersions are obtained in the melt using a combination of a permanent binder at low content < 3 wt% and an inexpensive commercial sacrificial binder. The sacrificial binder is a mixture of commercially available polymers made from conversion of carbon dioxide CO2.- The dispersions are then cast on the current collector using a calendaring process to yield 50-250 µm coatings depending on the final application (both high-energy and high-rate are possible).- The sacrificial binder is then degraded thermally at high speed at low temperature below 250°C to yield an electrode of tailored porosity possessing an improved adhesion to the collector compared to conventional PVDF solvent processed electrodes.Melt formulations were developed for several conventional Li-ion cathodes, namely LFP, NCA, NMC and conventional Li-ion anodes. A large range of loadings could be achieved, from 4 to 40 mg/cm2. Electrochemical performances in half cells will be presented, demonstrating high capacity and cyclability for high loadings, as well as the performances at high rates, up to 10 C.Important benefit of our process is reusage of already manufactured electrode material. Fabricated electrode material can be mixed with fresh blend to process a new electrode. Both cathode (NMC 622 and LFP) and anode (graphite) scraps were sucessfully remanufactured. The reprocessing does not alter electrode performance, even if we completely reuse old electrode material without diluting it into a fresh melt. That means that all scrap could be subsequently reprocessed without change in electrode performance.Moreover, the developed melt process is capable to reintegrate used cathode or anode material removed from its current collector (i.e. black mass) giving a new functional electrode. Such electrode material to be recycled can be initially manufactured via conventional solvent (NMP or aqueous) process with conventional binders (PVDF, CMC). Direct incorporation of up to 25 wt% recycled electrode materials including binders and conductive additives from used lithium-ion batteries into fresh electrode compositions in one step has been demonstrated. At our knowledge, that is a sole process able to directly recycle all electrode material without separation of active material from conductive carbon black and binder. Therefore, the presented melt process will illustrate shortening and better valuation of the battery production supply chain. Figure 1

Effect of a Heterogeneous Distribution of the Conductive Additives and Binder Domain on the Impedances of Lithium-Ion Battery Electrodes

The conductive carbon and binder are essential components of Lithium-ion battery electrodes. Their main task is to enhance the electrical connectivity and mechanical stability. Therefore, a homogeneous distribution of the carbon binder domain (CBD) throughout the electrode is desired. However, inhomogeneities can arise in the production process. At high drying rates of the wet coating, the CBD migrates to the surface of the electrode due to the drag of the evaporating solvent. This effect causes a gradient of the CBD through the thickness of the electrode. This process has two effects: (a) depletion of the CBD at the current collector, diminishing the electronic pathways and the adhesion of the electrode layer, and (b) accumulation of the CBD at the electrode surface, thus blocking pathways for Lithium transport. This is especially prominent in thick electrodes. Therefore, we investigate the effect of binder migration on the electrochemical performance of NMC622 electrodes of Lithium-ion batteries.In our simulations we use virtual electrode microstructures of NMC622 electrodes which are informed by tomography data. As it is challenging to resolve the CBD using tomographic techniques, it is distributed on a model-basis at the contact points of active material particles using an in-house structure generator[1].The valuable information derived from combining microstructure-resolved simulations with electrochemical impedance spectroscopy (EIS) on symmetric cells is used to characterize the Lithium-ion transport in the electrode pore space, including the contributions of the CBD. Additionally, half-cell discharge simulations are also conducted to analyze the effect of CBD heterogeneity on electrode performance.Through our work, we demonstrate the significance of the CBD distribution and enable predictive simulations for future battery design.[1] Hein S. et al, J. Electrochem. Soc. 2020, 167 013546 Figure 1

Methods—Kintsugi Imaging of Battery Electrodes: Distinguishing Pores from the Carbon Binder Domain using Pt Deposition

The mesostructure of porous electrodes used in lithium-ion batteries strongly influences cell performance. Accurate imaging of the distribution of phases in these electrodes would allow this relationship to be better understood through simulation. However, imaging the nanoscale features in these components is challenging. While scanning electron microscopy is able to achieve the required resolution, it has well established difficulties imaging porous media. This is because the flat imaging planes prepared using focused ion beam milling will intersect with the pores, which makes the images hard to interpret as the inside walls of the pores are observed. It is common to infiltrate porous media with resin prior to imaging to help resolve this issue, but both the nanoscale porosity and the chemical similarity of the resins to the battery materials undermine the utility of this approach for most electrodes. In this study, a technique is demonstrated which uses in situ infiltration of platinum to fill the pores and thus enhance their contrast during imaging. Reminiscent of the Japanese art of repairing cracked ceramics with precious metals, this technique is referred to as the kintsugi method. The images resulting from applying this technique to a conventional porous cathode are presented and then segmented using a multi-channel convolutional method. We show that while some cracks in active material particles were empty, others appear to be filled (perhaps with the carbon binder phase), which will have implications for the rate performance of the cell. Energy dispersive X-ray spectroscopy was used to validate the distribution of phases resulting from image analysis, which also suggested a graded distribution of the binder relative to the carbon additive. The equipment required to use the kintsugi method is commonly available in major research facilities and so we hope that this method will be rapidly adopted to improve the imaging of electrode materials and porous media in general.

Impact of carbon binders and carbon fillers on mercury intrusion and extrusion porosimetry of carbon-bonded alumina

Carbon-bonded alumina samples with different compositions and varying mixing and shaping procedures were tested regarding their densities, porosities, and pore entryway diameter distributions by means of helium pycnometry, buoyancy method and mercury intrusion porosimetry, respectively. A majority of the carbon-bonded alumina samples showed no release of the mercury from the pores during pressure reduction (extrusion), but a constant cumulative mercury volume. Samples without any carbon binder and uninitiated carbon binder showed an extrusion of mercury causing a hysteresis curve. Further tests yielded a strong adhesion between mercury and coked carbon binder, probably inducing the remainder of the mercury within the pores during the extrusion step. Despite the different sample compositions (due to omission of distinct raw materials) and pronounced differences in grain size, a majority of the measured bulk densities was in a similar range between 1.69 and 1.81 g/cm3.

Solving technological issues of fastening permanent magnets on the rotors of electrical machines with a power of up to 1 MW

Various options for designs and technological solutions for fastening permanent magnets on the rotor surface are considered. The technology of shrouding a rotor with permanent magnets with carbon structural threads is described. The technological equipment and equipment for performing the banding operation is described. Comparative mechanical tests of carbon fiber bandages were performed using carbon structural threads and binders from various manufacturers.

Boosting the oxygen evolution reaction performance of wrinkled Mn(OH)2 via conductive activation with a carbon binder

Electrochemical water splitting is one of the most reliable approaches for environmental-friendly hydrogen production. Because of their stability and abundance, Mn-based materials have been studied as electrocatalysts for the oxygen evolution reaction (OER), which is a more sluggish reaction in the water splitting system. To increase the OER activity of Mn, it is imperative to facilitate the structural change of Mn oxide to the active phase with Mn3+ species, known as the active site. Here, we present the relationship between the electronic conductivity in the catalyst layer and the formation of the Mn active phase, δ-MnO2, from wrinkled Mn(OH)2. Mn(OH)2 has poor conductivity, and it disrupts the oxidation reaction toward MnOOH or δ-MnO2. Adjacent conductive carbon to Mn(OH)2 enabled Mn(OH)2 to be oxidized to δ-MnO2. Furthermore, after repetitive cyclic voltammetry activation, the more conductive environment resulted in a higher density of δ-MnO2 through the irreversible phase transition, and thus it contributes to the improvement of the OER activity.

Effective Representation of Active Material and Carbon Binder in Porous Electrodes

Active cathode material and graphite anode material are routinely mixed with conductor and binder to improve the electric conductivity and mechanical stability of electrodes. Despite its benefits, this carbon binder domain (CBD) impedes ionic transport and reduces the active surface area, thus impacting the battery performance. We consider a composite spherical particle, whose active-material core is coated with CBD, and its homogeneous counterpart, for which we derived equivalent electrical conductivity, ionic diffusivity, and reaction parameters in the Butler-Volmer equation. These equivalent characteristics are defined to ensure that the same mass and charge enter the composite and homogenized spheres. They are expressed in terms of the volume fraction of the active material and transport properties of the active material and CBD. In general, the equivalent effective diffusion coefficient and reaction parameters are time-dependent and exhibit two-stage behavior characterized by the reaction delay time. At later times, these characteristics are time-independent and given explicitly by closed-form formulae. The simplicity of these expressions facilitates their use in single- and multi-particle representations of Li-ion and Li-metal batteries.

Self-standing mesoporous Si films as anodes for lithium-ion microbatteries

Silicon is the most promising anode material for next-generation lithium-ion batteries (LIBs) due to its high theoretical specific capacity and safe electrochemical potential. Among the different Si materials, mesoporous Si has attracted attention as the pores can accommodate the volume expansion during cycling, thus leading to stable battery cycling. However, carbon is often added to the electrode to improve the performance of the porous Si electrodes. To investigate the sole effects of the pore characteristics on the battery performance without any contribution from carbon, we produce self-standing mesoporous Si films with different porous structures through electrochemical etching and prepare electrodes without carbon additives or binders. Detailed pore analysis and electrochemical characterization of the Si films are performed to study their correlation. Correlation analysis shows that both reversible specific capacity and initial Coulombic efficiency (ICE) are mainly affected by the porosity and surface area, while the cycling performance is dictated by the film thickness over the pore characteristics. The best Si film anode delivers an ICE of 81.2% and stable cycling for over 450 cycles with a limited specific capacity of 1200 mAh g−1 in half cells. This study indicates the direction of the porous silicon material for high-performance LIBs.

Deep learning for full-feature X-ray microcomputed tomography segmentation of proton electron membrane fuel cells

This study demonstrates the benefit of convolutional neural networks to accurately classify the different materials of proton exchange membrane fuel cells using X-ray micro-computed tomography. Nineteen 2D orthoslices from a 3D tomography dataset were segmented with high quality and used to train a novel U-ResNet convolutional neural network (CNN) to segment the complete volume. The results were compared with a 3D manual segmentation performed under time constraints. The CNN segmented all phases with equal or greater accuracy in comparison to the manual segmentation. In particular, the CNN excelled in separating the carbon fibres and binder phase in the gas diffusion layer, which is usually completely avoided due to difficulty. Further, permeability calculations were performed on the binder void space for both segmentations, with the CNN displaying realistic results. Therefore, CNNs have been shown to be a viable and valuable method in segmenting such fuel cells with increased efficiency and accuracy.

Life cycle assessment of cementitious materials based on calcined sediments from Chorfa II dam for low carbon binders as sustainable building materials

This research was carried out to reuse calcined dredged sediments as a sustainable building material to reduce greenhouse gas emissions, and save significant energy consumption and costs. Moreover, the Life Cycle Assessment (LCA) of cementitious materials (cements, pastes, and mortars) based on calcined sediments was studied in order to quantify its energy consumption and Global Warming Potential (GWP). This study demonstrated that this calcined sediment could be used as a partial cement replacement in the cement industry in Algeria. The potential indicators of climate change for cements based on 0%, 5%, 15%, and 25% of calcined sediments release only 935.10 kg CO2 eq/T, 901.73 kg CO2 eq/T, 835 kg CO2 eq/T and 768.29 kg CO2 eq/T respectively, which represents a significant reduction of 3.57%, 10.70%, and 17.84%, for cement based on 5%, 15%, and 25% of calcined sediment. The potential indicators of climate change for pastes based on calcined sediments at 0%, 5%, 15%, and 25% rates release only 476.95 kg CO2 eq/T, 459.79 kg CO2 eq/T, 425.45 kg CO2 eq/T, and 391.12 kg CO2/T respectively, which represents a reduction of 3.6%, 10.80%, and 18%. Indeed, the potential indicators of climate change for mortars based on calcined sediments with 0%, 5%, 15%, and 25% rates release only 436.89 kg CO2 eq/T, 422.00 kg CO2 eq/T, 393.07 kg CO2 eq/T, and 364.40 kg CO2/T respectively, which represents a reduction of 3.41%, 10.03%, and 16.59%. In conclusion, the LCA of cements, mortars, and pastes with a high substitution rate of calcined sediments offer the best reduction in environmental impacts. These results present prospects for industrializing calcined sediments as green building materials in the cement industry.

Influence of carbon binder domain on the performance of lithium‐ion batteries: Impact of size and fractal dimension

AbstractA lithium‐ion battery (LIB) cathode comprises three major components: active material, electrical conductivity additive, and binder. The combination of binder and electrical conductivity additive leads to the formation of composite clusters known as the carbon binder domain (CBD) clusters. Preparation of a LIB cathode strongly influences the dispersion of the above‐mentioned constituents leading to the formation of distinct pore and electrical conduction networks. The resulting structure thus governs the performance of LIBs. The presence of CBD is essential for the structural integrity and sufficient electrical conductivity of the LIB cathode. However, CBD abundance in LIB cathodes leads to unfavorable gravimetrical and volumetrical consequences owing to its electrochemical inertness. Increasing CBD content adds to the weight of the LIBs, thus negatively impacting the energy density. Furthermore, increased electrical conductivity is won at a cost of ionic conductivity as CBD clusters breach the pore networks in the cathode microstructure. The following study establishes a link between the various possibilities of CBD cluster size and fractal dimension that may eventualize during the mixing process of slurry preparation to the resulting microstructural properties and hence to the performance of LIBs by means of idealized cathode geometries. Since the performance determining processes occur at the microstructural scale, which are often very tedious to study via experimental research, the study makes use of spatially resolving microstructural, numerical, simulations. The results demonstrate that the CBD cluster size has a strong influence on the cathode microstructure. The CBD cluster fractal dimension on the other hand displayed a minor influence on the structural properties of the cathode, and the size of the cluster primary particles was shown to be the dominant factor. Finally, performance evaluation simulations confirmed the trends seen in structural properties with changing cluster size and fractal dimension.

Deconvoluting the impacts of the active material skeleton and the inactive phase morphology on the performance of lithium ion battery electrodes

In order to extract the most capacity out of Li-ion battery (LIB) active materials, the optimization of the electrodes architectures at the mesoscale is essential. This work focuses on the morphology of the inactive phase (carbon additives and binder) through a 3-D modeling approach based on stochastic generation of electrode mesostructures with realistic LiNi1/3Mn1/3Co1/3O2 particle size distributions. It was found that having the inactive phase as a film spread on the active material results in poorer performance in part due to the loss of active surface area when compared to an agglomerate-like morphology.

Structurally Reinforced Silicon/Graphene Composite for Lithium-Ion Battery Anodes: Carbon Anchor as a Conductive Structural Support.

Herein, a Si/reduced graphene oxide (rGO)/C microsphere composite is reported, wherein sucrose-derived carbon binds Si nanoparticles (NPs) and rGO to act as a carbon anchor and links neighboring rGO sheets to reinforce the composite structure. In this structurally reinforced Si/rGO/C composite, the electron conduction pathways between rGO and Si NPs were maintained even under large volume changes during repeated charge-discharge processes. Consequently, the Si/rGO/C composite anode exhibited an initial discharge capacity of 1209 mAh g-1 and superior cyclability (92 % retention at 100 cycles), initial coulombic efficiency of 80.5 %, and high-rate capability even at a high C rate (6 C). Furthermore, the change in anode thickness after repeated cycling was negligible, confirming the structural stability imparted by the sucrose-derived carbon binder. A full cell assembled with a LiCoO2 cathode and the Si/rGO/C composite anode remained stable over 200 cycles.

Metal-Organic Framework Glass Anode with an Exceptional Cycling-Induced Capacity Enhancement for Lithium-Ion Batteries.

Metal-organic frameworks (MOFs) hold great promise as high-energy anode materials for next-generation lithium-ion batteries (LIBs) due to their tunable chemistry, pore structure and abundant reaction sites. However, the pore structure of crystalline MOFs tends to collapse during lithium-ion insertion and extraction, and hence, their electrochemical performances are rather limited. As a critical breakthrough, a MOF glass anode for LIBs has been developed in the present work. In detail, it is fabricated by melt-quenching Cobalt-ZIF-62 (Co(Im)1.75 (bIm)0.25 ) to glass, and then by combining glass with carbon black and binder. The derived anode exhibits high lithium storage capacity (306 mAh g-1 after 1000 cycles at of 2 A g-1 ), outstanding cycling stability, and superior rate performance compared with the crystalline Cobalt-ZIF-62 and the amorphous one prepared by high-energy ball-milling. Importantly, it is found that the Li-ion storage capacity of the MOF glass anode continuously rises with charge-discharge cycling and even tripled after 1000 cycles. Combined spectroscopic and structural analyses, along with density functional theory calculations, reveal the origin of the cycling-induced enhancement of the performances of the MOF glass anode, that is, the increased distortion and local breakage of the CoN coordination bonds making the Li-ion intercalation sites more accessible.