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The development of affordable and safe lithium-ion batteries (LIB) which feature high storage capacity represents one of the priority strategies toward further introduction of green technologies in our everyday life. This paper presents a study into the candidate composite anodes for high energy LIB; these utilize reversible high storage capacity of ions of lithium in the form of alloys of the latter with nano-sized silicon, imbedded in a soft-carbon matrix, which in turn, are deposited on a robust graphitic core. These structures allow an efficient contact between the constituents to be realized at the same time providing space for Si nano-particles during lithiation/de-lithiation process. The synthetic route described herein has a high potential for a cost-effective scale-up with the battery materials industry. Presented results demonstrate feasibility for creation of new active materials for the negative electrodes in LIB, which feature the storage capacity up to 700 mAh g−1 at C/2 and in excess of 1450 mAh g−1 at C/20 cycling rates, respectively. This work also shows that the use of acrylic binder has a positive effect on the overall system performance, as compared to state-of-the-art PVDF-based binder systems. © 2013 The Electrochemical Society. [DOI: 10.1149/2.006310jss] All rights reserved.

A low-temperature wet chemistry technique for producing carbon nanoscrolls is described. The technique is based on the use of readily available acceptor-type graphite intercalation compounds. The initial graphite intercalation compound is first exfoliated to produce a suspension of graphene monolayers in ethanol which is subsequently sonicated yielding a suspension of carbon nanoscrolls. The technique does not require heating and the use of inert atmosphere thus providing an improvement compared to the previously reported methods.

The paper is devoted to the development of lithium-ion battery grade negative electrode active materials with higher reversible capacity than that offered by conventional graphite. The authors report on results of their experiments as related to the electrochemical performance of silicon-based materials for lithium-ion batteries. A commercial grade of spherically shaped natural graphite (FormulaBT™ SLA1025) was modified in a number of different ways with nano-sized silicon. The reversible capacity of SLA1025 modified by 9.2 wt% of the nano-sized amorphous silicon was seen to be as high as 590 mAh g−1. The irreversible capacity loss with this compound was 20%. Lithium-ion batteries using such material were observed to display sharp capacity decay during prolonged cycling. In contrast, the reversible capacity of another experimental grade, the SLA1025 modified by 7.9 wt% of the carbon-coated Si was as high as 604 mAh g−1. The irreversible capacity loss with this material was as low as 8.1%. This grade, also, was seen to display much better cycling performance than the baseline natural graphite. A series of full lithium-ion rechargeable cells were developed in the CR2016 coin cell configuration. Higher specific capacity of graphite modified by silicon was observed. This allowed decreasing graphite content in the lithium-ion cells by a factor of 1.6. The resultant lithium-ion batteries after optimization of their composition displayed approximately 20% higher gravimetric and volumetric specific energy densities than lithium-ion battery based on conventional natural graphite.

Authors introduce an ultrahigh-temperature (i.e., 2500–3000 °C) continuous fluidized bed furnace, in which the key operating variable is specific electrical resistance of the bed. A correlation has been established to predict the specific electrical resistance for the natural graphite-based precursors. Fluid dynamics models have been validated with the data from a fully functional prototype reactor. Data collected demonstrated that the difference between the calculated and measured values of specific resistance is approximately 25%; due to chaotic nature of electrothermal fluidized bed processes, this discrepancy was deemed acceptable. Optimizations proposed allow producing natural graphite-based end product with the purity level of 99.98 + wt. %C for battery markets.

A gas diffusion layer (GDL) for proton exchange membrane fuel cell has been developed using a new form of partially ordered graphitized nano-carbon black (PUREBLACK® Carbon). This material represents a new class of nano-carbons jointly developed by Superior Graphite Co. and Columbian Chemicals Co. The GDL was characterized by physico-chemical as well as electrochemical methods. The unique process developed for GDL fabrication exhibits excellent fuel cell performance using hydrogen/air at ambient pressure. The microstructure as seen under scanning electron microscope shows excellent surface morphology without any cracks. The membrane electrode assembly (MEA) with PUREBLACK® Carbon based GDLs shows power density as high as 0.55 W/cm2 at 70 °C using hydrogen/air as reactants without any back pressure. Keywords: PEM fuel cells, Membrane electrodes assembly, Gas diffusion layers, Electrochemical measurements, PUREBLACK® Carbon, Partially graphitized carbon black

Graphitization heat treatment of a precursor carbon black was seen to effectively produce a wide variety of forms of partially graphitized nano-sized carbonaceous materials with a set of unique properties, some of which are reported in this paper in comparison with those properties of the precursor carbon material. These novel materials were given the name of PUREBLACK ® Carbons. Among some of the unique properties are: higher conductivity than that of acetylene type carbon blacks due to PUREBLACK ® Carbon's particles having more graphitic structure; very low to zero volatile content (external oxygen, sulfur, etc., groups, which are often believed to be the cause of initiation of self-discharge reactions in batteries); very low equilibrium moisture pickup (20 ppm level), which makes it particularly attractive in lithium metal or lithium-ion based electrochemical systems; high purity. Electrochemical testing of the newly proposed PUREBLACK ® Carbons in several battery systems offers significant promise that it presents a viable solution to the needs of industry.

The main advantage of carbon material treatment in electro-thermal furnaces with fluidized bed [EFFB] at 2000–3000C is that they allow producing graphite of high chemical purity, which is especially important in manufacture of ion-lithium batteries. The team conducted extensive research into hydraulic and heat modes of such units and developed a methodology for their design based on the concept of increase in electric resistance with fluidization. The choice of the working space configuration and the operation mode of EFFB are largely determined by the specific electrical resistance [SER] of the fluidized bed. This parameter is a complex function of a number of factors: fluidization character, uniformity of the bed and the temperature, nature and size of the material fractions, current density and furnace atmosphere composition. It is vital to take into account relationships between SER, working temperature T and current density i, which eventually define electrothermal mode of the unit operation. Thus, if graphite size is d = 130μm within temperature range T = 0–2500C and current density i = 0,004–1.0 A/cm2, SER varies in reverse proportion to these parameters Statistic processing of the experimental data allowed to obtain regressive function SER = f (i, t), which we used as the basis of mathematic modeling, heat balance calculation and predicting transitory and operation modes of EFFB with 10kg/hour productivity: SER=0.01.84.711-2.,593*10-2.T-46.854*i+1.205*10-2.T*i,Ω-m′ Resulting volt-ampere characteristics (VACs) of the furnace have maximum values at constant temperature (T = const) which is explained by the non-linear character of the SER function. There exists a technological temperature limit of EFFB responsible for its stable operation. The furnace operation beyond the stability margin depends on the power source characteristics which may cause a sharp power drop or a shorting. The VAC characteristics are determined by the type of material, geometry of the furnace working space, electrode diameter, active zone height, the gap between the electrode and the lining, design of heat insulation and the cooling system. Taking these parameters into consideration, it is possible to conduct a preliminary analysis of the unit stable operation modes as early as during the design stage.

The electrochemical peculiarities of classical redox systems with solid-state reagents (non-soluble quinones, intercalation compounds of graphite) as well as polyaniline-type conducting polymers have been considered. The conducting polymers show a significant non-faradaic component of the electrochemical mechanism. The essential differences of faradaic and non-faradaic systems in equilibrium behavior, trends of galvanostatic charge–discharge curves and cyclic voltammograms have been shown, and criteria for the identification of these mechanisms are proposed. Our investigations of the current-producing mechanism for the polyaniline electrode have shown that at least within a narrower range of potentials Δ E n from 0.30–0.40 to 0.80–0.90 V versus SHE (depending on pH value) the ‘capacitor’ model of ion electrosorption/desorption in well conducting emeraldine salt phase is more preferable. Nevertheless, such a model should take into account the transport of both anions and protons (cations in a general case). Besides the possibilities of redox processes at the limits and beyond this range of potentials Δ E n should be taken into account. At the same time, these processes can lead to the fast formation of thin passive layers of new poorly conducting phases (leucoemeraldine salt, leucoemeraldine base, etc.) near the current collector. The formation of such phases, even in a small amount, rapidly inhibits and discontinues the electrochemical process.

An innovative technology for processing selected recycled battery wastes from large format automotive lithium-ion batteries has been developed. One of the key steps of refining process is application of thermal treatment of granular matter in a new and improved modified electrothermal fluidized bed reactor at high temperature. The reactor design is based on fluidization and increase in electric resistance leading to higher temperatiures.

Novel composite anode materials were prepared for use in lithiumion batteries. The composite material formation involved coating of powdered substrates (graphite-, or silicon-based), thus modifying their surface properties and cycling performance. Applying an additional surface coating resulted in the production of composites with enhanced stability in the practical lithium-ion battery environments. Coin cell cycling, as well as full 7Ah prismatic cell cycling, and impedance spectroscopy methods were used to evaluate the electrochemical properties of coated materials.

Preface. 1. New Carbon Materials for Supercapacitors. Subject Overview. Novel Carbonaceous Materials for Application in the Electrochemical Supercapacitors E. Frackowiak et al.- Effect of Carbonaceous Materials on Performance of Carbon-Carbon and Carbon-Ni Oxide Types of Electrochemical Capacitors with Alkaline Electrolyte A. I. Belyakov.- Hybrid Supercapacitors Based on a-MnO2/Carbon Nanotubes Composites V. Khomenko et al.- Development of Supercapacitors Based on Conducting Polymers V. Khomenko et al.- Supercapacitors: Old Problems and New Trends Y. Malein et al.- Modeling Porosity Development During KOH Activation of Coal and Pitch-Derived Carbons for Electrochemical Capacitors K. Kierzek et al.- General Properties of Ionic Liquids as Electrolytes for Carbon-Based Double Layer Capacitors A. Lewandowski, M. Galinski.- 2. Carbon Materials for Gas Diffusion Electrodes, Metal Air Cells and Batteries. Subject Overview.- New Concept for the Metal-Air Batteries Using Composites: Conducting Polymers/Expanded Graphite as Catalysts V. Z. Barsukov et al.- Mechanically Rechargeable Magnesium-Air Cells with NaCl-Electrolyte A. Kaisheva, I. Iliev.- Application of Carbon-Based Materials in Metal-Air Batteries: Research, Development, Commercialization A. Kaisheva, I. Iliev.- Metal - Air Batteries with Carbonaceous Air Electrodes and Nonmetallic Catalysts N. Korovin.- 3. Carbon Anodes for Lithium-Ion Batteries. Subject Overview.- Carbonaceous Materials for Batteries T. Takamura, R. J. Brodd.- Anode-Electrolyte Reactions in Li Batteries: The Differences Between Graphitic and Metallic Anodes H. J. Santner et al.-Performance of Novel Types of Carbonaceous Materials in the Anodes of CLAiO's Lithium-Ion Battery Systems M. Walkowiak et al.- Why Graphite Electrodes Fail in PC Solutions: An Insight from Morphological Studies D. Aurbach et al.- New Developments in the Advanced Graphite for Lithium-Ion Batteries F.-X. Henry et al.- Mechanisms ofReversible and Irreversible Insertion in Nanostructured Carbons Used for Li-Ion Batteries F. Beguin et al.- Some Thermodynamics and Kinetics Aspects of the Graphite-Lithium Negative Electrode for Lithium-Ion Batteries R. Yazami et al.- Characterization of Anodes Based on Various Carbonaceous Materials for Application in Lithium-Ion Cells A. N. Kozhevnikov et al.- A Carbon Composite for the Negative Electrode of Li-Ion Batteries A. V. Churikov et al.- Electrochemical Intercalation of PF and BF into Single-Walled Carbon Nanotubes R. Yazami et al.- Surface Treated Natural Graphite as Anode Material for High-Power Li-Ion Battery Applications J. Liu et al.- 4. Emerging Metal/Carbon Composite Anodes for Next Generation Lithium-Ion Batteries. Subject Overview.- On The Theoretical Prerequisites for Application of Novel Materials in Promising Energy Systems V. Z. Barsukov, J. E. Doninger.- Capabilities of Thin Tin Films as Negative Electrode Active Materials for Lithium-Ion Batteries Y. O. Illin et al.- Composite Anode Materials for High Energy Density Lithium-Ion Batteries J. S. Gnanaraj et al.- Electrochemical Activity of Carbons Modified by d-Metal Complexes with Ethanolamines L. G. Reiter et al.- Metal-Graphite Composites as Materials for Electrodes of Lithium-Ion Batteries L. Matzui et al.- Electrochemical Performance of Ni/Cu-Metallized & Carbon-Coated Graphites for Lithium Batteries C. S. Johnson et al.- 5. New Nano- Through Macro-Carbons for Energy Systems: Synthesis, Modeling, Characterization. Subject Overview.- Stabilization of Graphite Nitrate via Co-intercalation of Organic Compounds M. V. Savoskin et al.- Electrochemical Stability of Natural, Thermally Exfoliated and Modified Forms of Graphite towards Electrochemical Oxidation I. O. Kovalenko et al.- Low Temperature Synthesis of Graphite from Iron Carbide S. Dimovski et al.- High Resolution Transmission Electron Microscopy Image Analysis of Disordered Carbons Used for Electrochemical

Final report on the US DOE CARAT program describes innovative R & D conducted by Superior Graphite Co., Chicago, IL, USA in cooperation with researchers from the Illinois Institute of Technology, and defines the proper type of carbon and a cost effective method for its production, as well as establishes a US based manufacturer for the application of anodes of the Lithium-Ion, Lithium polymer batteries of the Hybrid Electric and Pure Electric Vehicles. The three materials each representing a separate class of graphitic carbon, have been developed and released for field trials. They include natural purified flake graphite, purified vein graphite and a graphitized synthetic carbon. Screening of the available on the market materials, which will help fully utilize the graphite, has been carried out.

The electrochemical performance of a series of natural and synthetic graphite powders was investigated for their viability as anode materials in lithium-ion batteries. The variation of the charge and discharge capacities can be qualitatively correlated to their structural and morphological differences. The specially treated natural graphite samples show excellent capacity and relatively small irreversible capacity losses. A noticeable percentage of the rhombohedral phase was observed in the natural graphite samples. The good electrochemical performance of these graphite powders may be attributed to the combination of low surface area and absence of exfoliation due to the presence of the rhomhohedral phase and defects in the grain boundaries Graphitized cokes generally exhibited larger irreversible capacity loss, and mesophase carbons produced relatively low reversible capacity.