Computer Simulation of an Electrode of Lithium-Ion Battery: Estimation of Ohmic Losses for Active-Material Grains Covered by a Conducting Film
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The use of active materials with high resistivity in lithium-ion batteries necessitates covering the surface of active particles with electron-conducting films. If this measure is insufficient, then carbon black is added to the electrode active layer. The ohmic losses are assessed by computer simulation of electrode’s active layers with active grains covered by a carbon film. Electrode’s active layer is modeled as a set of equal-sized cubic grains of the active material (covered with a conducting film) and the electrolyte; the grains are randomly distributed throughout the active layer. It is shown how the effective conductivity of the active layer decreases in this case. Furthermore, account is taken of the fact that carbon films represent a set of islets, which results in an additional decrease in the effective conductivity of the active layer. By computer simulations in combination with the percolation theory, it is found how the addition of carbon black can increase the conductivity of electrode’s active layer.
Keywordslithium-ion battery ohmic losses porous electrodes computer simulations electron-conducting coatings
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- 2.Huang, H., Yin, S.C., and Nazar, L.F., Approaching theoretical capacity of LiFePO4 at room temperature at high rates, Electrochem. Solid State Lett., 2001, vol. 4, p. A170.Google Scholar
- 3.Kostecki, R., Schnyder, B., Alliata, D., Song, X., Kinoshita, K., and Kotz, R., Surface studies of carbon films from pyrolyzed photoresist, Thin Solid Films, 2001. vol. 396. p. 36.Google Scholar
- 10.Doeff, M.M., Hu, Y., McLarnon, F., and Kostecki, R., Effect of surface carbon structure on the electrochemical performance of LiFePO4, Electrochem. Solid-State Lett., 2003, vol. 6, p. A207.Google Scholar
- 13.Chen, C.H., Vaughey, J.T., Jansen, A.N., Dees, D.W., Kahaian, A.J., Goacher, T., and Thackeray, M.M., Studies of Mg-substituted Li4–xMgxTi5O12 spinel electrodes (0 < x < 1) for lithium batteries, J. Electrochem. Soc., 2001, vol. 148, p. A102.Google Scholar
- 15.Wolfenstine, J., Lee, U., and Allen, J.L., Electrical conductivity and rate-capability of Li4Ti5O12 as a function of heat-treatment atmosphere, J. Power Sources. 2006, vol. 154, p. 287.Google Scholar
- 20.Jung, H.-G., Kim, J., Scrosati, and Sun, Y.-K., Micron-sized, carbon-coated Li4Ti5O12 as high power anode material for advanced lithium batteries, J. Power Sources, 2011, vol. 196, p. 7763.Google Scholar
- 32.Chirkov, Yu.G., Porous electrodes in electrochemical technologies, Al’tern. Energ. Ecol., 2014, no. 9, p. 55 [in Russian].Google Scholar
- 33.Skundin, A.M., Chirkov, Yu.G., and Rostokin, V.I., Lithium-ion batteries: Computer simulation and problems of capacity dependences on charge/discharge currents, Al’tern. Energ. Ecol., 2014, no. 13, p. 80 [in Russian].Google Scholar
- 34.Tarasevich, Yu.Yu., Perkolyatsiys: teoriya, prilozheniyz, algoritmy (Percolation: Theory, Applications, Algorithms), Moscow: Editorial URSS, 2011 [in Russian].Google Scholar
- 35.Chirkov, Yu.G., The theory of porous electrodes: percolation, calculation of percolation lines, Russ. J. Electrochem., 1999, vol. 35, p. 1281.Google Scholar