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A novel fabrication method comprising screen-printing and sintering of nanotitania/carbon paste has been developed allowing the construction of binder-free electrodes with superior lithium-ion intercalation properties. As a model active material to demonstrate the advantages of the new fabrication process, commercial P25 nanotitania product was used. The newly fabricated electrodes were compared to those fabricated using the standard binder-based method. Physical characterization demonstrated that the novel binder-free paste provides for significant carbon dispersion due to smaller agglomerate size resulting in enhanced inter-particle (active-conducting) mixing and packing density than the standard one. Cyclic voltammetry and galvanostatic charge/discharge testing proved the novel method-built electrodes to exhibit dramatically improved performance over the standard electrode in terms of conductivity, specific charge capacity, and reversibility. Thus the specific charging (delithiation) capacity of the novel method electrode (92% TiO 2 /7.5% C) was 174 mA h g −1 , compared to 124 mA h g −1 for the standard method electrode (85% TiO 2 /7.5% C/7.5% PVDF), representing 103, and 74% of the theoretical capacity (corresponding to Li 0.5 TiO 2 ), respectively. At the same time after 10 cycles, the novel-built electrode exhibited 90-94% coulombic efficiency and more than 92% capacity retention while the corresponding values for the standard electrode were only 80-82% and 53% respectively.With the growing demand for Electric Vehicles (EV), R&D in Lithium-Ion Batteries (LIB) has intensified in recent years. 1-4 Current LIBs are limited, among other reasons, by their energy storage, power density, ability to charge and discharge at high rates, but also while LIBs show promise, commercial scale-up and application of these electrochemical energy storage devices has exposed another limiting factor for the acceptance of EVs: cost. 5,6 This has driven research to focus on higher performance energy storage solutions. 2,3,7-10 Researchers have centered their efforts on experimenting with various electrode chemistries, nanomaterials, and fabrication routes. 6,[11][12][13][14][15][16][17] While much research revolves around cathode materials, the anode materials have been studied extensively as well. The most common material for anodes is graphite, 18,19 however there are problems associated with its safety/long-life performance that is required of LIBs destined for electric vehicles arising from the formation of the well known Surface-Electrolyte Interface (SEI) layer. 20 Graphene, 21,22 SnO 2 , 12 Si-based, 23,24 Li 4 Ti 5 O 12 , 9,25,26 and most recently TiO 2 12,27-31 have attracted attention as alternative to graphite anode materials. Titania, at the nano scale, can potentially find application in both LIBs (as an anode), or in supercapacitors due to its ability to store energy via lithiation as well as via pseudocapacitive behavior at high charge and discharge rates, 32,33 and its lack of an SEI layer. Other attractive feature...

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In this work the potential of employing electrophoretic deposition (EPD) for fabricating Li-ion battery electrodes without using binders and in particular eliminating volatile and toxic organic solvents such as n-methyl 2-pyrrolidone (NMP) is demonstrated. The paper in particular describes the successful application of the EPD method to fabrication of thick (>20 μm) nano-TiO 2 /carbon Li-ion intercalation anodes. The EPD system involves deposition of commercial P25 TiO 2 nanoparticles and carbon black on aluminum foil from an isopropanol bath without making use of charging agents or other additives. Hetero-coagulation of TiO 2 and C particles in the isopropanol medium enabled their 80 V DC cathodic deposition into a well-adhered film with effective intermixing of active and conductive components. Electrochemical testing of the newly binder-free EPD-built electrodes revealed comparable film conductivity, polarization and charge storage capacity properties with the standard binder-based PVDF/NMP electrodes. Most importantly, the charge storage, cycling, and rate properties of the EPD-built electrodes were greatly enhanced by post-EPD sintering of the film at 450 • C. The combined EPD-sintering route resulted in a superior conductive percolating network by promoting nanoscale film composition uniformity, inter-particle necking, and favorable porous structure for enhanced interfacing with the liquid electrolyte. The sintered EPD-built electrode exhibited almost 50% higher capacity retention than that of the standard binder-based electrode upon cycling. EPD with its inherent self-assembling functionality and its overall operational simplicity provides an advantageous and green Li-ion electrode fabrication alternative. Lithium ion batteries (LIBs) are by far the most advanced electrochemical energy storage cells that are presently powering at an ever increasing pace not only mobile electronics but also electric transportation and renewable energy installations. [1][2][3][4] There is tremendous R&D effort in progress to develop increasingly higher performance electrode (anode and cathode) materials and electrolytes 5 to meet the new range of LIB applications, as is the case of electric vehicles. 6 However in this effort equally important is the selection of materials and fabrication technologies that not only lead to high energy and power density LIBs but also are governed by sustainability and affordability principles. It is in this context that the present work seeks to develop a green Li-ion fabrication technology featuring electrophoretic deposition and non-toxic abundant chemicals and materials.Present state-of-the-art electrode fabrication for lithium-ion batteries involves mixing the active powder material (anode or cathode), conductive carbon, and the binder (poly(vinilydene) fluoride, PVDF) by typically dispersing them in a solvent, then tape casting the slurry onto a current collector substrate, and finally followed by drying (at 120• C) and calendaring/pressing. 7 The high cost of PVDF binder and the require...

Mesoporous TiO2 rutile particles with a cauliflower‐like morphology and an internal structure of self‐assembled nanoneedles were synthesized in a novel TiIV chloride aqueous‐solution hydrolysis process. In an effort to make nanostructured rutile synthesis cost‐effective and green, the process was conducted at steady‐state in a continuously stirred tank reactor (CSTR) below 100 °C. High TiCl4 concentration 0.5–1 m yielded rutile, while lowering the concentration to 0.1 m led to the crystallization of brookite nanoplatelets. Apart from phase control, specific surface area of rutile may be tuned via TiCl4 concentration regulation from 85 to 500 m2 g−1. Investigation revealed that low pH/high TiIV concentration conditions favored direct nucleation of rutile nuclei during steady state that grow radially outward into nanoneedle structured cauliflower particles with nanoscale edgy surface. The unique steady‐state produced mesoporous rutile particles were shown to have excellent light scattering properties in a bi‐layer photoanode structure resulting in 42.5 % increase in photovoltaic efficiency. Brookite nanoplatelets were shown, in addition to their scattering properties, to exhibit stable Li‐ion intercalation functionality.