Effect Of Conductive Additives Research Articles

The effect of conductive additives on electrochemical performance of LiFePO<sub>4</sub>-based lithium slurry batteries

<p indent="0mm">Lithium slurry batteries are promising large-scale energy-storage devices because of their low cost, long life, and independent scalability of energy and power capabilities. Electrode slurry is the main component of lithium slurry batteries and its conductive and rheological properties play an important role in the electrochemical performance of batteries. Herein, the types and amounts of conductive additives on the conductivity and rheology of LiFePO₄-based cathode slurry were investigated. By comparing the viscosity, suspension stability and conductivity of different cathode slurries, the 1.0 wt.% LFP–KB cathode slurry displayed a better electrochemical performance. Based on this cathode slurry, the lithium slurry batteries exhibited a stable cycle performance over 450 h. This work provides a guidance to select conductive additives for lithium slurry batteries.

Effects of conductive additives on the percolation networks and rheological properties of LiMn0.7Fe0.3PO4 suspensions for lithium slurry battery

In depth understanding the evaluation behaviors of conductive percolation networks and rheological properties is important for developing high performance suspension electrodes. Herein, three kinds of conductive additives, Ketjen Black, multi-walled carbon nanotubes and graphene nanoplatelets, are utilized to systematically investigate the impacts of dimension and content on the rheological and electrochemical properties of LiMn0.7Fe0.3PO4 suspensions. The percolation threshold ranges are found to be 0.5–0.6 wt.%, 0.2–0.3 wt.% and 2.3–2.4 wt.% for KB, MWCNT and GNP-based suspensions, respectively. The inflection points for electronic conductivities of different conductive additives based suspensions are situated at 1.0 wt.%, 0.5 wt.% and 2.5 wt.%, respectively, and the static viscosities and yield stresses of KB and MWNCT-based suspensions possess the same inflection points as those of electronic conductivities. Nevertheless, GNP-based suspensions deliver a distinguishing tendency due to their relatively poor dispersion. Electrochemical characterizations indicate that 1.5 wt.% KB-based suspension delivers superior cycle and rate performances. Especially, the successful application of LMFP suspension to lithium slurry battery was demonstrated by a relatively stable cycle over 230 h. Our findings will be helpful for the development of lithium slurry batteries with robust conductive networks and high energy density.

Effect of conductive additives on the transport properties of porous flow-through electrodes with insulative particles and their optimization for Faradaic deionization

Deionization devices that use intercalation reactions to reversibly store and release cations from solution show promise for energy-efficient desalination of alternative water resources. Intercalation materials often display low electronic conductivity that results in increased energy consumption during desalination. Accordingly, we performed experiments to quantify the impact of the size and mass fraction of conductive additives and insulative active particles on the effective electronic conductivity, ionic conductivity, and hydraulic permeability of porous electrodes. We find that Ketjen black conductive additives with nodules <50 nm in diameter produce superior electronic conductivity at lower mass fractions than the larger carbon blacks commonly used in capacitive deionization. Hydraulic permeability and effective ionic conductivity depend weakly on carbon black content and size, though smaller active particles decrease hydraulic permeability. Based on these results we analyzed the energy consumption and salt removal rate of different electrode formulations by constructing an electrochemical Ashby plot predicting the variation of desalination performance with electrode transport properties. Optimized electrodes containing insulative Prussian blue analogue (PBA) particles were then fabricated and used in an experimental cation intercalation desalination (CID) cell with symmetric electrodes. For 100 mM NaCl influent energy consumption varied from 7 to 33 kJ/mol when current density increased from 1 to 8 mA/cm2, approaching ten-fold increased salt removal rate at similar energy consumption levels to past CID demonstrations. Complementary numerical and analytical modeling indicates that further improvements in energy consumption and salt removal rate are attainable by enhancing transport in solution and within PBA agglomerates.

Enhanced biomethane recovery from fat, oil, and grease through co-digestion with food waste and addition of conductive materials

In this study, the effect of conductive additives on co-digestion of fat, oil, and grease (FOG) and food waste (FW) was evaluated. Initially, biochemical methane potential (BMP) test was conducted for optimization of mixing ratio of FW and FOG. The optimal methane production (800 L (kg VS)−1) was obtained from co-digestion of 70% FW + 30% FOG (w/w), which was 1.2 times and 12 times of that obtained from mono-digestion of FW and FOG, respectively. This optimal mixing ratio was used for subsequent fed-batch studies with the addition of two conductive additives, granular activated carbon (GAC) and magnetite. The addition of GAC significantly shortened the lag phase (from 7 to 3 d), reduced accumulation of various volatile fatty acids (VFAs), and enhanced methane production rate (50–80% increase) compared to the control and magnetite-amended bioreactor. Fourier transformation infrared (FTIR) analysis suggested that the degradation of lipids, protein and carbohydrates was the highest in GAC amended reactor, followed by magnetite and control reactors. GAC addition also enriched more abundant and diverse bacteria and methanogens than control. Magnetite addition also showed similar trends but to a lesser degree. The substantial enrichment of syntrophic LCFA β-oxidizing bacteria (e.g. Syntrophomonas) and methanogenic archaea in the GAC-amended bioreactor likely attributed to the superior methanogenesis kinetics in GAC amended bioreactor. Our findings suggest that the addition of GAC could provide a sustainable strategy to enrich kinetically efficient syntrophic microbiome to favor methanogenesis kinetics in co-digestion of FW and FOG.

알칼리용액에서 La0.8Sr0.2MnO3페롭스카이트 촉매의 산소환원 및 발생반응에서 도전재의 영향

알칼리용액에서 La_0.8Sr_0.2MnO₃페롭스카이트 촉매의 산소환원 및 발생반응에서 도전재의 영향

Effect of Conductive Additives on the Structural and Electrochemical Properties of Li4Ti5O12Spinel

The effect of a conductive agent on the structural and electrochemical properties of <TEX>$Li_4Ti_5O_{12}$</TEX>(LTO) spinel was investigated through neutron diffraction during Li intercalation and electrochemical measurements. The charging process of LTO is known as transformation of the white <TEX>$(Li_3)_{8a}[LiTi_5]_{16d}O_{12}$</TEX> into a dark-colored <TEX>$(Li_{3-X})_{8a}[Li_{X+Y}]_{16c}[LiTi_5]_{16d}O_{12}$</TEX> by incorporating the inserted Li into octahedral 16c sites, and the Li in tetrahedral 8a sites shifted to 16c sites. The occupancy of the tetrahedral 8a site varied with the existence of carbon in the electrode. Without carbon, the lattice parameter and cell volume of LTO decreased more notably than in the carbon-containing LTO electrode during Li insertion process. These phenomena might be attributed that the Li occupancy of the tetrahedral 8a of the LTO electrode without carbon was less than that of the carbon-containing LTO electrode.

Influence of conductive additives and surface fluorination on the charge/discharge behavior of lithium titanate (Li 4/3Ti 5/3O 4)

Effect of conductive additives and surface modification with NF 3 and ClF 3 on the charge/discharge behavior of Li 4/3Ti 5/3O 4 (≈4.6 μm) was investigated using vapor grown carbon fiber (VGCF) and acetylene black (AB). VGCF and mixtures of VGCF and AB increased charge capacities of original Li 4/3Ti 5/3O 4 and those fluorinated with NF 3 by improving the electric contact between Li 4/3Ti 5/3O 4 particles and nickel current collector. Surface fluorination increased meso-pore with diameter of 2 nm and surface area of Li 4/3Ti 5/3O 4, which led to the increase in first charge capacities of Li 4/3Ti 5/3O 4 samples fluorinated by NF 3 at high current densities of 300 and 600 mA g −1. The result shows that NF 3 is the better fluorinating agent for Li 4/3Ti 5/3O 4 than ClF 3.

Effect of Conductive Additives and Surface Fluorination on the Electrochemical Properties of Lithium Titanate ( Li4 / 3Ti5 / 3O4 )

The effect of conductive additives and surface fluorination on the charge/discharge behavior of was investigated. Mixtures of acetylene black (AB) and vapor-grown carbon fiber (VGCF) gave larger first charge capacities at a high current density of 600 mA/g than those obtained when AB or VGCF was used as a conductive additive by improving the electric contact between particles and a nickel current collector. The surface fluorination of by improved the thermal stability of the electrolyte solution without decreasing first charge capacities and first coulombic efficiencies.

All-solid-state lithium secondary batteries using sulfide-based glass–ceramic electrolytes

Highly lithium ion conducting glass–ceramics in the system Li 2S P 2S 5 were successfully prepared by a heat treatment of the mechanochmically prepared sulfide glasses. The 80Li 2S·20P 2S 5 (mol.%) glass–ceramic mainly composed of the crystal analogous to the highly conductive thio-LISICON II phase in the system Li 4− x Ge 1− x P x S 4 showed conductivity as high as 10 −3 S cm −1 at room temperature. The 70Li 2S·30P 2S 5 glass–ceramic, in which the highly ion conductive new metastable phase was formed on heating, showed the highest conductivity of 3.2 × 10 −3 S cm −1 and the lowest activation energy of 12 kJ mol −1 for conduction. The all-solid-state battery In/80Li 2S·20P 2S 5 glass–ceramic/LiCoO 2 exhibited excellent cycling performance of over 500 times with no decrease in the charge–discharge capacity (100 mAh g −1). The SnS P 2S 5 glasses as active materials were mechanochemically prepared from SnS and P 2S 5. High performance of these glassy electrode materials was observed in the rechargeable cell of 80SnS·20P 2S 5/80Li 2S·20P 2S 5 glass–ceramic/LiCoO 2, in which a continuous sulfide network between electrode and electrolyte was successfully formed. The effects of conductive additives in composite electrodes on charge–discharge behavior of all-solid-state cells with Li 2S P 2S 5 glass–ceramics as a solid electrolyte were investigated. Under a current density over 1 mA cm −2, the cell with vapor grown carbon fiber kept larger discharge capacities during 50 cycles than the cell with acetylene black. The design of continuous electron conducting path from a point of view of morphology for conductive additives is important to improve cell performances of all-solid-state lithium secondary batteries.

Effects of Conductive Additives in Composite Positive Electrodes on Charge-Discharge Behaviors of All-Solid-State Lithium Secondary Batteries

The effects of conductive additives in composite positive electrodes on charge-discharge behaviors of all-solid-state cells with glass-ceramic electrolytes were investigated. Acetylene black (AB), vapor grown carbon fiber (VGCF), titanium nitride (TiN), and nickel metal (Ni) were used as conductive additives. Carbon materials were more effective to decrease the resistivities of composite positive electrodes compared to TiN and Ni. Under a current density of , discharge capacities of about were maintained over in the cell with VGCF, while gradual decreases in discharge capacities were observed in the cells with AB, TiN, and Ni. Furthermore, even under a current density over , the cell with VGCF kept larger discharge capacities during than the cell with AB. Since VGCF is composed of submicrometer-ordered fibers, close solid-solid contacts among electrode, electrolyte, and VGCF were achieved. The design of continuous electron conducting paths from a point of view of morphology for conductive additives is important to improve cell performances of all-solid-state lithium secondary batteries.