Study of lithium intercalation into different nanostructured cathode based on oxides of transition metal using ionic liquid (ILs) with low viscosity synthesized from phosphonium and tetracyanoborate like electrolytes.

• Grant number: 14/01987-6
• Support type: Scholarships in Brazil - Post-Doctorate
• Effective date (Start): October 01, 2014
• Effective date (End): September 30, 2017
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Physical-Chemistry
• Principal Investigator: Roberto Manuel Torresi
• Grantee: Nédher Sánches Ramírez
• Home Institution: Instituto de Química (IQ). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated scholarship(s): 15/11164-0 - Study of lithiation of silicon nanopowder produced by induced plasma using ionic liquids as electrolytes, BE.EP.PD

Abstract

At present, the challenge of lithium ion batteries is to develop systems with higher ciclability, and high power and energy densities. While the carbon negative electrode possess good performance (high cyclability and high reversible charge density above 370 mAhg-1) cobalt oxide, LiCoO2, the electroactive material that is typically used as positive electrodes, have many disadvantages, such as low practice specific charge (140 mAhg-1), and thermal instability in charged(oxidized) state. Among the various active materials which can be used as positive electrodes, the composite transition metal NMC (LiNi1/3Mn1/3Co1/3O2) and NCA (LiNi0.8Co0.15 Al0.05O2) are promising ones due to their low cost, good charge storage capacity and low toxicity. On the other hand the need for lithium-ion batteries with high power and high energy density carries a safety related issue due to problems associated to the organic solvents typically used as electrolytes. It is known that ionic liquids (ILs) can be used as electrolytes once they are non-flammable and have high thermal and electrochemical stability. However, ILs with good transport properties which allow easy diffusion of lithium are necessary. For this reason ILs derived from tetracyanoborate anion and phosphonium cation will be prepared. These structures have low coordination capacity that causes a decrease of coulombic interactions. In this project cathodes derived from transition metals and ionic liquids with excellent transport properties will be prepared.

Scientific publications

(4)

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

SANCHEZ-RAMIREZ, NEDHER; ASSRESAHEGN, BIRHANU DESALEGN; TORRESI, ROBERTO M.; BELANGER, DANIEL. Producing high-performing silicon anodes by tailoring ionic liquids as electrolytes. ENERGY STORAGE MATERIALS, v. 25, p. 477-486, MAR 2020. Web of Science Citations: 1.

MARTINS, VITOR L.; RENNIE, ANTHONY J. R.; SANCHEZ-RAMIREZ, NEDHER; TORRESI, ROBERTO M.; HALL, PETER J. Improved Performance of Ionic Liquid Supercapacitors by using Tetracyanoborate Anions. CHEMELECTROCHEM, v. 5, n. 4, p. 598-604, FEB 2018. Web of Science Citations: 8.

SANCHEZ-RAMIREZ, NEDHER; ASSRESAHEGN, BIRHANU DESALEGN; BELANGER, DANIEL; TORRESI, ROBERTO M. A Comparison among Viscosity, Density, Conductivity, and Electrochemical Windows of N-n-Butyl-N-methylpyrrolidinium and Triethyl-n-pentylphosphonium Bis(fluorosulfonyl imide) Ionic Liquids and Their Analogues Containing Bis(trifluoromethylsulfonyl) Imide Anion. JOURNAL OF CHEMICAL AND ENGINEERING DATA, v. 62, n. 10, p. 3437-3444, OCT 2017. Web of Science Citations: 11.

MARTINS, VITOR L.; SANCHEZ-RAMIREZ, NEDHER; RIBEIRO, MAURO C. C.; TORRESI, ROBERTO M. Two phosphonium ionic liquids with high Li+ transport number. Physical Chemistry Chemical Physics, v. 17, n. 35, p. 23041-23051, 2015. Web of Science Citations: 20.