Anna Potapenko - Academia.edu (original) (raw)
Papers by Anna Potapenko
Journal of Solid State Electrochemistry
Russian Journal of Electrochemistry, 2020
The electrochemical properties of batteries consist of LiFePO4 (LFP) with the NV-1A binder were s... more The electrochemical properties of batteries consist of LiFePO4 (LFP) with the NV-1A binder were studied in depth. It was shown that SEI layer for NV-1A formed on the electrodes has a lower resistance as compared with PVDF. It is known that the increase discharge current loads lead to decrease an average voltage and the specific capacity of a battery. However, in the case of NV-1A binder the changing average discharge voltage and the specific capacity at the increasing current loads is not significant. Thus, the capacity fall is 18 and 220 mA h for NV-1A and PVDF binders for LIBs consist from LFP cathode material with different binders with an increase in discharge currents from 0.1 to 2.0 C, respectively. It should be noticed that the electrochemical properties of the LFP–NV-1A system were completely studied the first time not only in half-cells but in the full battery complete state.
ECS Transactions, 2021
The paper discusses the electrochemical behavior of a Li-S battery with a new water-soluble binde... more The paper discusses the electrochemical behavior of a Li-S battery with a new water-soluble binder NV-1A. It is shown that the main contribution is made by the interface, which is formed on the lithium counter electrode. It is noteworthy that the nonlinear growth of the resistance of SEI layer during the discharge process correlates with the change in the resistance of charge transfer through the interface.
ECS Transactions, 2020
The electrochemical properties of LiMn2O4 surface modified with LiNi0.5Mn1.5O4 at different curre... more The electrochemical properties of LiMn2O4 surface modified with LiNi0.5Mn1.5O4 at different current densities are presented. The electrode with a maximum percentage of covering (14% of LiNi0.5Mn1.5O4) can endure higher current loads compared with the sample consisting 7% of surface layer. The capacity values for these samples at 45° and 30°C are 22 and 31 mAh∙g-1, respectively. This means that the proposed approach can be an effective tool for obtaining electrode materials for high-rate applications.
Electrochimica Acta, 2018
Li 4 Ti 5 O 12 precursors have been synthesized by means of a citric acid aided route using TiCl ... more Li 4 Ti 5 O 12 precursors have been synthesized by means of a citric acid aided route using TiCl 4 as a raw material. The pyrolysis of the precursors has been performed in air and in argon. Comparison shows that pyrolyzing citrate precursors in argon instead of air one can obtain a material having twice smaller particle size and much better electrochemical properties (specific capacity and discharge rate). Specifically, Li||Li 4 Ti 5 O 12 cells with Li 4 Ti 5 O 12 pyrolyzed in argon return 148 mА•h/g upon 1.0C current load, 70 mA•h/g upon 30C current load and 32 mA•h/g upon 60C current load. These values exceed those obtained with a commercial Li 4 Ti 5 O 12 material. For Li 4 Ti 5 O 12 pyrolyzed in air, increasing discharge currents from 1.0C to 30C decreases discharge capacity from 125 to 40 mA•h/g.
NEW FUNCTIONAL SUBSTANCES AND MATERIALS FOR CHEMICAL ENGINEERING, 2021
Precipitation of hydroxides and carbonates from solutions containing complex compounds is a valua... more Precipitation of hydroxides and carbonates from solutions containing complex compounds is a valuable industrial process enabling one to synthesize electrode materials with high density particles of microspherical morphology and high tap density. As a complex formation agent, ammonia is almost exclusively used in this process. Aiming at the search of other complex formation agents and the detailed studies of complex formation at precipitation, we have first investigated the hydrolysis of solutions containing citric acid. Equilibria in solutions containing citrate complexes of manganese and carbonates are computed. It is found that in Mn(NO3)2 - хC6H8O7∙H2O - уNa2CO3 systems, a neutral Mn(HCitr) complex dominates up to pH=9.5 and precipitation of MnCO3 from carbonate containing solutions begins at рН~6.5. Experiments show that MnCO3 precipitates from these systems in the form of openwork quasi-spherical aggregates formed by nanosized crystals. The synthesis of LiMn2O4 from this precur...
Electrochimica Acta, 2017
Ukrainian Chemistry Journal
Studies have shown the possibility of a long cycle of sulfur electrode with a high content of act... more Studies have shown the possibility of a long cycle of sulfur electrode with a high content of active material. The use of water-soluble binder material NV-1A leads to the realization of high current loads in the Li-S battery. Impedance spectroscopy has shown that the low coulombic efficiency in the cycling of the sulfur electrode is primarily due to the spontaneous dissolution of sulfur in the electrolyte, which requires high energy consumption when charging the Li-S battery. The reduction of the specific capacity during cycling is associated with the formation and accumulation of non-conductive films of short-chain polysulfides. On the basis of the conducted researches and the review of the literature sources ways of overcoming of this problem are offered. The ability of cycling the sulfur electrodes at the high current loads has been shown. The discharge capacity values of the sulfur electrodes at the current load 790 mA∙cm-2 are 500 і 420 mAh∙g-1 on the 5-th and 100-th cycles, ac...
Journal of Solid State Electrochemistry
Lithium-manganese-rich-lithiated nickel-manganese-cobalt oxides are advantageous for using in lit... more Lithium-manganese-rich-lithiated nickel-manganese-cobalt oxides are advantageous for using in lithium-ion batteries due to low toxicity and high specific capacity but suffer from low high-rate capability. In this paper, characterization and electrochemical testing of 0.5Li 2 MnO 3 •0.5LiNi 0.5 Mn 0.3 Co 0.2 O 2 (Li 1.2 Ni 0.2 Mn 0.52 Co 0.08 O 2) obtained by means of a citric acid-aided route is described. It demonstrates excellent electrochemical performance possessing specific capacity equal to the theoretical value (280 mAh g −1), being able to be discharged with currents of 2240 mA g −1 (8 C), having high coulombic efficiency (~99%) even after high-rate tests, and manifesting low capacity fade after high current loads and upon further cycling by 0.1 C currents (0.144 mAh g −1 per cycle). Keywords LMR-NMC materials. Lithium-ion batteries. 0.5Li 2 MnO 3 •0.5LiNi 0.5 Mn 0.3 Co 0.2 O 2 (Li 1.2 Ni 0.2 Mn 0.52 Co 0.08 O 2). High-rate performance * Sviatoslav A. Kirillov
Journal of Solid State Electrochemistry
Journal of Solid State Electrochemistry
Russian Journal of Electrochemistry, 2020
The electrochemical properties of batteries consist of LiFePO4 (LFP) with the NV-1A binder were s... more The electrochemical properties of batteries consist of LiFePO4 (LFP) with the NV-1A binder were studied in depth. It was shown that SEI layer for NV-1A formed on the electrodes has a lower resistance as compared with PVDF. It is known that the increase discharge current loads lead to decrease an average voltage and the specific capacity of a battery. However, in the case of NV-1A binder the changing average discharge voltage and the specific capacity at the increasing current loads is not significant. Thus, the capacity fall is 18 and 220 mA h for NV-1A and PVDF binders for LIBs consist from LFP cathode material with different binders with an increase in discharge currents from 0.1 to 2.0 C, respectively. It should be noticed that the electrochemical properties of the LFP–NV-1A system were completely studied the first time not only in half-cells but in the full battery complete state.
ECS Transactions, 2021
The paper discusses the electrochemical behavior of a Li-S battery with a new water-soluble binde... more The paper discusses the electrochemical behavior of a Li-S battery with a new water-soluble binder NV-1A. It is shown that the main contribution is made by the interface, which is formed on the lithium counter electrode. It is noteworthy that the nonlinear growth of the resistance of SEI layer during the discharge process correlates with the change in the resistance of charge transfer through the interface.
ECS Transactions, 2020
The electrochemical properties of LiMn2O4 surface modified with LiNi0.5Mn1.5O4 at different curre... more The electrochemical properties of LiMn2O4 surface modified with LiNi0.5Mn1.5O4 at different current densities are presented. The electrode with a maximum percentage of covering (14% of LiNi0.5Mn1.5O4) can endure higher current loads compared with the sample consisting 7% of surface layer. The capacity values for these samples at 45° and 30°C are 22 and 31 mAh∙g-1, respectively. This means that the proposed approach can be an effective tool for obtaining electrode materials for high-rate applications.
Electrochimica Acta, 2018
Li 4 Ti 5 O 12 precursors have been synthesized by means of a citric acid aided route using TiCl ... more Li 4 Ti 5 O 12 precursors have been synthesized by means of a citric acid aided route using TiCl 4 as a raw material. The pyrolysis of the precursors has been performed in air and in argon. Comparison shows that pyrolyzing citrate precursors in argon instead of air one can obtain a material having twice smaller particle size and much better electrochemical properties (specific capacity and discharge rate). Specifically, Li||Li 4 Ti 5 O 12 cells with Li 4 Ti 5 O 12 pyrolyzed in argon return 148 mА•h/g upon 1.0C current load, 70 mA•h/g upon 30C current load and 32 mA•h/g upon 60C current load. These values exceed those obtained with a commercial Li 4 Ti 5 O 12 material. For Li 4 Ti 5 O 12 pyrolyzed in air, increasing discharge currents from 1.0C to 30C decreases discharge capacity from 125 to 40 mA•h/g.
NEW FUNCTIONAL SUBSTANCES AND MATERIALS FOR CHEMICAL ENGINEERING, 2021
Precipitation of hydroxides and carbonates from solutions containing complex compounds is a valua... more Precipitation of hydroxides and carbonates from solutions containing complex compounds is a valuable industrial process enabling one to synthesize electrode materials with high density particles of microspherical morphology and high tap density. As a complex formation agent, ammonia is almost exclusively used in this process. Aiming at the search of other complex formation agents and the detailed studies of complex formation at precipitation, we have first investigated the hydrolysis of solutions containing citric acid. Equilibria in solutions containing citrate complexes of manganese and carbonates are computed. It is found that in Mn(NO3)2 - хC6H8O7∙H2O - уNa2CO3 systems, a neutral Mn(HCitr) complex dominates up to pH=9.5 and precipitation of MnCO3 from carbonate containing solutions begins at рН~6.5. Experiments show that MnCO3 precipitates from these systems in the form of openwork quasi-spherical aggregates formed by nanosized crystals. The synthesis of LiMn2O4 from this precur...
Electrochimica Acta, 2017
Ukrainian Chemistry Journal
Studies have shown the possibility of a long cycle of sulfur electrode with a high content of act... more Studies have shown the possibility of a long cycle of sulfur electrode with a high content of active material. The use of water-soluble binder material NV-1A leads to the realization of high current loads in the Li-S battery. Impedance spectroscopy has shown that the low coulombic efficiency in the cycling of the sulfur electrode is primarily due to the spontaneous dissolution of sulfur in the electrolyte, which requires high energy consumption when charging the Li-S battery. The reduction of the specific capacity during cycling is associated with the formation and accumulation of non-conductive films of short-chain polysulfides. On the basis of the conducted researches and the review of the literature sources ways of overcoming of this problem are offered. The ability of cycling the sulfur electrodes at the high current loads has been shown. The discharge capacity values of the sulfur electrodes at the current load 790 mA∙cm-2 are 500 і 420 mAh∙g-1 on the 5-th and 100-th cycles, ac...
Journal of Solid State Electrochemistry
Lithium-manganese-rich-lithiated nickel-manganese-cobalt oxides are advantageous for using in lit... more Lithium-manganese-rich-lithiated nickel-manganese-cobalt oxides are advantageous for using in lithium-ion batteries due to low toxicity and high specific capacity but suffer from low high-rate capability. In this paper, characterization and electrochemical testing of 0.5Li 2 MnO 3 •0.5LiNi 0.5 Mn 0.3 Co 0.2 O 2 (Li 1.2 Ni 0.2 Mn 0.52 Co 0.08 O 2) obtained by means of a citric acid-aided route is described. It demonstrates excellent electrochemical performance possessing specific capacity equal to the theoretical value (280 mAh g −1), being able to be discharged with currents of 2240 mA g −1 (8 C), having high coulombic efficiency (~99%) even after high-rate tests, and manifesting low capacity fade after high current loads and upon further cycling by 0.1 C currents (0.144 mAh g −1 per cycle). Keywords LMR-NMC materials. Lithium-ion batteries. 0.5Li 2 MnO 3 •0.5LiNi 0.5 Mn 0.3 Co 0.2 O 2 (Li 1.2 Ni 0.2 Mn 0.52 Co 0.08 O 2). High-rate performance * Sviatoslav A. Kirillov
Journal of Solid State Electrochemistry