литий-ионные аккумуляторы

In this study, the electrochemical behavior and properties of the novel LiFePO4-based composite cathode material with a water-soluble binder LA-133 and a conductive polymer PEDOT:PSS (poly-3,4-ethylenedioxythiophene: polystyrenesulfonate) as an aqueous dispersion were studied. Using the conductive polymer in combination with a water-soluble binder LA-133 allows to reduce the proportion of electrochemically inactive components (up to 10\%) and thus to increase its specific capacity for a given weight of the active material.

Electrochemical properties of the electrode based on lithium-manganese spinel (LiMn2O4), which were produced with conducting and binder additives using a conductive polymer poly-3,4-ethylenedioxythiophene/polystyrene sulfonate (PEDOT:PSS) with carboxymethylcellulose (CMC) were investigated by cyclic voltammetry in aqueous and organic solutions of lithium perchlorate. Values of specific capacitance of the cathode material and their dependence on potential sweep rate were obtained.

The study of new anode material based on Li₄Ti₅O₁₂ and conducting polymer binder have been performed with use of cyclic voltammetry method. It was shown, that modified composition of anode material has superior properties in comparison with standard composition with PVDF in term of higher specific capacity and kinetic of charge transfer properties. Using of PEDOT:PSS/CMC binder allow to increase of specific capacity up to 14%.

The critical analysis of literature of last 15 years, concerning features of low-temperature behavior of lithium-ion batteries is presented. Some generalized approaches to the problem as well as the role of main polarization components at low temperatures; features of functioning of negative and positive electrodes are reviewed. Some low-temperature electrolytes are reviewed as well.

DOI: https://doi.org/10.18500/1608-4039-2017-17-1-19-28

The review of cathode materials for lithium-ion batteries is presented, the analysis of advantages and application prospects of cathode materials on the basis of lithiated transition metals oxides is carried out. A method of heterovalent modification by ions of highly negative elements, lanthanum and its analogues for improving the electrochemical indices and stability of lithium manganese spinel is proposed. The effectiveness of fullerene, lithium fluoride, fullerenes halogen derivatives as modifying additive for MnO₂ cathode materials has been noticed.

The second part of the review describes the prospects of using alternative polymer binders for composite electrodes of lithium electrochemical systems. Possible options having been taken into account, the most popular commercially-available synthetic polymers with functional group (the ones forming aqueous solutions or dispersions predominantly) and water-soluble polymers of natural origin are considered. The versatility of such materials is their distinctive feature.

The current situation in technology and developments in the field of polymer binders for composite electrodes of lithium electrochemical systems are discussed. A wide range of synthetic and natural polymers used for this purpose is considered. Emphasis is placed on commercially available materials, which form aqueous solutions or dispersions. The advantages of multifunctional polymer binders are demonstrated.

The third part of the review is devoted to polymer binders with electronic conductivity used to make composite electrodes for lithium electrochemical systems. Polymer semiconductors (“synthetic metals”), related polymers with additionally introduced functional groups, related copolymers and mixtures of polymers, as well as carbon chain polymers and copolymers with inсorporated polyaromatic fragments are considered.