литий-ионный аккумулятор

Characterization by in situ or operando methods is very important to deeper understand the chemical and electrochemical processes, as well as the degradation processes that occur during the operation of a lithium-ion battery.

Doped lithium titanate is known to be able to reversibly cycle in the potential range from 3 to 0.01 V and this ability depends both on the nature of the dopant and the doping level. In this work Li₄Ti₅O₁₂ samples doped with Nd in the amount of 0.5 to 2.0% were studied. It was shown that while being cycled in the extended potential range, the samples with the doping level from 0.5 to 1.0% demonstrated the highest capacity.

The possibility of determining the charge state of lithium-sulfur batteries using the ANFIS model was estimated. Easily measurable in practice physical quantities were used as input parameters of the model. They are the battery voltage, the rate of its change and the number of previous cycles. The analysis of ANFIS models with various parameters (the number and type of membership functions) was carried out. It was shown that ANFIS is a model that makes it possible to estimate the charge state of a lithium-sulfur battery with the accuracy of more than 95%.

Using literature information about the temperature effect on the electrochemical behavior of electrodes based on LiFePO₄ and Li₄Ti₅O₁₂ being positive and negative electrodes of a lithium­ion battery, the discharge characteristics of batteries with such electrodes and various ratios of the amount of active material on the electrodes in the temperature range from −15 to +60°C were calculated.

Nanotubes of bronze titanium dioxide (TiO₂(B)) doped with vanadium were synthesized through hydrothermal reaction. The obtained material possesses mesoporous structure and large specific surface area of 180 m²/g. It was found that the incorporation of vanadium into TiO₂(B) lattice increases the volume of a unit cell. Additionally, the conductivity rose up to three orders of magnitude for doped titanium dioxide reaching the value of 1.70 ⋅ 10^− 8 S/cm.

Within the work, an influence of manganese dopant on electrochemical performance of anatase titanium dioxide (Mn/Ti = 0.05; 0.1; 0.2) had been investigated. It was established that incorporation of Mn³⁺ into the TiO₂ lattice results in the formation of Ti_1 − xMn_xO₂ solid solution and increased anatase unit cell volume from 136.41 Å³ (undoped sample) to 137.25 Å³ (Mn/Ti = 0.05). The conductivity of doped TiO₂ rises up to two orders in magnitude.

This paper discusses the prospects for developing a cathode material based on the cobalt(II)-lithium vanadate(V) (LiCoVO₄) for a lithium-ion battery, an approach to its preparation and features of the electrochemical behavior.

Various strategies for the synthesis of promising electrode materials for lithium-ion battery (LIB) based on iron(II)-lithium orthosilicate (Li₂FeSiO₄) using widely distributed, environmentally friendly and inexpensive starting materials are considered. The materials obtained are multicomponent electroactive composites that include, in addition to the main lithium accumulating component, also auxiliary structure-forming and electrically conductive components based on the products of the pyrolytic decomposition of organic compounds.

To model the characteristics of lithium-sulfur batteries based on the experimental evaluation of the electrochemical properties of electrode materials, the software "Battery Designer", included in the software package “ElChemLab”, was developed. The possibilities of software are described. The specific energy of lithium-sulfur batteries is compared for different surface capacitances of a positive electrode and for different amounts of electrolyte.

DOI: https://doi.org/10.18500/1608-4039-2018-18-3-133-140