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1 M solutions of NaClO4 mixed with ethylene carbonate, dimethyl carbonate, and fluoroethylene carbonate were studied as electrolytes for a double-layer supercapacitor with electrodes made of Norit DLC Supra 30 activated carbon. It was shown that the specific capacity of activated carbon depends on the electrolyte composition, range of cycling voltages, and current density. The maximum specific capacitance of 40 F g–1 was obtained in 1 M NaClO4 mixed with ethylene carbonate: dimethyl carbonate: fluoroethylene carbonate (4: 5: 1) at a current density of 36 mA g–1 in the range 10–2300 mV. The minimum specific capacitance was obtained under the same cycling conditions in the electrolyte with 1 M NaClO4 + ethylene carbonate: dimethyl carbonate (1: 1). The variation of the specific capacitance with the electrolyte composition and range of cycling voltages is accounted for by the existence of a pseudocapacitance caused by the occurrence of side processes on the surface of activated carbon. The impedance spectroscopy was used to find that the introduction of fluoroethylene carbonate into the electrolyte positively affects the charge-transfer resistance and favors an increase in the specific capacitance of activated carbon.

Еlectrochemical performance of Co 3 O 4 in lithium-ion batteries is briefly reviewed. Co 3 O 4 samples are synthesized via microwave-assisted solid state and citric acid aided methods. It is shown that the latter method leads to disperse nanosized materials having discharge capacity close to the theoretical value. Several electrolytes are probed so as to minimize capacity losses upon cycling, and the one containing lithium bis(trifluoromethane)sulfonimide in a mixture of fluoroethylene carbonate and dimethyl carbonate is selected. High-rate tests reveal that capacity retention of the samples obtained is well comparable with the best existing data, and at the current load of 5340 mA g −1 (6C) all materials studied retain more than 50% of initial capacity.

We propose the optimal composition of a polyligand ammonium-chloride-fluoride electrolyte and a mode of electrolysis for the deposition of functional coatings formed by tin–nickel alloys. The tin–nickel alloy with a tin content of 65 wt.% and a nickel content of 35 wt.% proves to be the most promising for microelectronics in the case of its application instead of gold coatings. It is shown that the obtained coatings are suitable for soldering with the use of low-temperature solders and acid-free fluxes and for the ultrasonic spot welding. The electrolytic deposits of tin–nickel alloys are investigated as the anodes of lithium–ion batteries by the potentiodynamic and galvanostatic cycling methods. It is shown that the deposits obtained from an alkaline tartrate-trilonate electrolyte are characterized in the first cycles by a high specific capacity of up to 700 mA ∙ h/g. In the course of cycling, this parameter decreases to 500 mA ∙ h/g. The obtained tin–nickel alloys guarantee high densities of charge-discharge currents without mechanical fracture.

The electrochemical behavior of electric double layer capacitors (EDLCs) with tetramethylammonium bis(oxalato)borate electrolyte and electrodes based on various activated carbons (ACs) was studied. Tetraalkylammonium bis(oxalate)borate salts were synthesized by means of microwave (MW) irradiation. The specific conductivities of salt solutions were determined. It was shown that the efficiency of electric double layer capacitors increases with an increase in specific surface area and a decrease in the purity of carbon materials.

Synthesis of Co3O4 powders by the microwave method from citrate precursors is described. The structural, surface, and thermogravimetric characteristics of the resulting powders were studied depending on the cobalt ions and citric acid ratio. The specific capacity of the samples was determined to be from 665 to 831 mA h g–1 after 100 cycles at a current density of 0.5C.

The specific characteristics of natural pyrite (FeS2) are investigated using a galvanostatic cycling method. The investigation is carried out for electrolytes consisting of dimethylcarbonate (DMC) and a lithium salt (LiBF4, LiClO4, or LiN(CF3SO2)2). It is shown that the specific capacitance of FeS2 and its stability during cycling depend on the concentration and the nature of a lithium salt anion. The greatest efficiency of the galvanostatic cycling of FeS2 is achieved for the DMC-LiClO4 and DMC-LiN(CF3SO2)2 electrolytes in salt concentrations in the range of 0.1–0.2 molar fractions.

The synthesis method of lithiated d-metal oxides using molten formate mixtures as precursors has been developed and the isothermal (800 °C) cross section of pseudo ternary Li–Mn–Co oxide system under ambient oxygen pressure has been investigated by XRD, 7Li NMR, and galvanostatic electrochemical methods. Special attention has been paid to the compositions inside the quadrangle restricted by solid solutions LiCoO2–LiCo0.85Mn0.15O2 with the layered structure of α-NaFeO2 and solid solutions LiMn2O4–LiMnCoO4 with the structure of spinel. It was found that, depending on the composition, three types of equilibrium phases could be formed: spinels Li[Li,Mn,Co]2O4 with a part of Li atoms in octahedral sites, cation-deficit layered compounds Li1 − δ[Co,Mn]O2, and Li2MnO3. Areas of (co)existence of these phases were plotted on the composition plane of the pseudo-ternary Li–Mn–Co system. Electrochemical properties of the compositions inside the quadrangle LiCoO2–LiCo0.85Mn0.15O2–LiMn2O4–LiMnCoO4 are determined by the content and average oxidation number of Mn atoms, which is higher than in the normal spinels Li[Mn,Co]2O4. Thus, the specific capacities of the polyphase compositions are lower in comparison with the binary solid solutions Li[Mn,Co]2O4 or pure LiCoO2.

Potentiodynamic and galvanostatic cycling in 1 M ethylene carbonate-dimethyl carbonate solution of LiClO4 were used to study electrolytic tin films deposited from complex (tartrate, citrate, and citrate-trilonate) electrolytes. It was shown that the nature of a ligand strongly affects the electrochemical characteristics, specific capacity of tin films, and efficiency of their cycling in lithium power sources. The most stable charge-discharge characteristics are inherent in tin films deposited from the citrate electrolyte.

The electrochemical characteristics of natural pyrite FeS2 in electrolytes based on salt-solvate mixtures (lithium bis(trifluoromethane)sulfonamide and linear ethers) have been investigated. The specific capacity (Q) of natural pyrite during cycling within the temperature range of 20–80°C has been estimated. It has been shown that, at room temperature, the Q value for FeS2 depends on the concentration of lithium salt and on the linear ether nature. In diluted solutions, the specific capacity values are close and do not depend on the nature of the linear ether. In salt-solvate electrolytes, the specific capacity varies in the following range: monoglyme (MG) > tetraglyme (TG) > diglyme (DG), which is apparently due to the conductivity, which reduces in a similar sequence. The higher the temperature, the higher the discharge capacity of pyrite. It is typical for both the first cycle and the cycling as a whole. The specific capacity values of FeS2 at 60°C in DG (0.44 LiImid) and TG (0.5 LiImid) electrolytes appear to be almost equal and correspond to about 500 mA h/g. It is shown that the “open circuit voltage-introduced lithium amount” dependence does not differ significantly in diluted and salt-solvate electrolytes during the first cycle. However, the difference becomes more apparent during cycling of FeS2.

Electrolytic deposits of tin-nickel alloys as anodes for lithium-ion batteries were investigated by potentiodynamic and galvanostatic cycling methods in solutions of ethylene carbonate, dimethyl carbonate, and LiClO4 (1 mol/L). It has been shown that the deposits of tin-nickel alloys obtained from alkaline tartrate-trilonate electrolytes in the first cycles are characterized by a high specific capacity of up to 700 mA h/g, which decreases to 500 mA h/g during the cycling. The tin-nickel alloys obtained are able to ensure high charge-discharge current densities without mechanical destruction.

Results of the examination of the electrochemical characteristics of a lithium-manganese spinel in LiBOB-tetraethylene glycol dimethyl ether (tetraglyme) electrolytes as a function of the LiBOB concentration and the cycling and storage temperatures are described. According to the results, the lithium-manganese spinel in electrolytes based on LiBOB-tetraglyme mixtures exhibits a high specific capacity and ability for stable cycling over a wide temperature range. The conductivity of the solutions is governed by the salt concentration, and its temperature dependence is linear in the coordinates of the Vogel-Tamman-Fulcher equation in the temperature range of 10–100°C. The studies were conducted using a lithium anode in 2016 disc cells.

The structural and electrochemical features of LixMn2O4 spinel synthesized by the microwave-assisted method are discussed. The thermal gravimetric analysis shows that almost 84% of all the initial reactants undergo chemical transformation associated with the weight loss in the course of the microwave-assisted synthesis. The composition of the initial components influences the heating rate negligibly, and the temperature reaches 400°C within around 15 minutes. The X-ray phase analysis shows that the LixMn2O4 samples contain impurities such as MnO2 and Mn2O3, the amount of which decreases with the increase in the lithium content. The electrochemical characteristics of the LixMn2O4 are strongly influenced by the composition of the starting components, which is particularly noticeable upon high discharge rates.

A procedure for preparing new lithium salts with large organic anions, which can be used as additives to nonaqueous electrolytes of high-capacity chemical power sources, was developed. The electro-chemical properties of the salts were studied.

In the plasticized and gel-like polymer, electrolytes containing such aprotic solvents as plasticizers, cations and anions of lithium salts are mobile. As a rule the transport number of lithium ions in these systems is far less than 1 (usually 0.5). Such a situation can result from the possibility of cation binding by polymer matrix polar groups (e.g., -Oin polyethylene oxide, -CN in polyacrylonitrile, -NR in polyamide, etc). In this case, an anion can contribute more to the conductivity than a cation can. The problems of the undesirable participation of anions in ion transport and decreasing reactivity of polymer electrolytes relative to the electrode materials can be solved by using lithium organic salts with large anions. This is illustrated by the increased interest in the application of new organic and inorganic lithium salts in the composition of polymer electrolytes

The authors discuss the effectiveness of an overhaul done on a 3000-m/sup 3/ blast furnace with previous design deficiencies. During the overhaul, the diameter of the reinforcement of the bottom was enlarged from 14,330 to 15,130 mm. Other changes included replacing the lining in the region of the joint between the hearth and bottom by a single block, lengthening and widening the main troughs, and increasing the thickness of the shell of the bustle pipe. During the overhaul the bustle pipe was lined with refractories ShLB-1.0 and KL-1.3 and two courses of MKV-72. The reconstruction made it possible to alter the operating parameters of the furnace. The authors aimed to minimize heat loss with the coolant water from the stack and top and to maximize the gas permeability of the stock. Productivity of the furnace in the post-overhaul period increased 5432 tons/day at a coke consumption of 483 kg/ton pig.

lurgical Combine studied the effect of the size of the openings in regenerator checkers on the technicoeconomic indices of 300- and 600-ton open-hearth furnaces fired with natural gas and carburetted fuel oil. The furnaces are operated by the scrap-ore process with 62-64% hot metal in the charge, and they have one pair of regenerators. The volume and heating area of the checkers are 295 m s and 3100 m = for the 300-ton furnaces and 352 m 3 and 3725 m 2 for the 600-ton furnaces. The roofs of the slag pockets and regenerators are made of magnesite-chromite bricks. The walls of the pockets and the top part of the generators are faced on the inside with the s~nne type of brick. The top part of the checkerwork is constructed of T-shaped fireclay brick. The dimensions of the openings in the regenerators are 155 x 155 n~n, 197 x 197 ntm, 230 x 230 ram, and 275 x 275 nnn. The combination method is used to supply oxygen to the flame and to the bath for blowing. To evalute the degree of heat recovery, we measured the temperature of the blower air and the flue gases with suction-type thermocouples. Here, to study the effect of the age TABLE i. Change in the Performance Indices of 300- and 600-ton Open-Hearth Furnaces in Relation to the Size of the Regenerator Checkerwork Openings