TY - JOUR KW - Diffusion KW - Lithium compounds KW - Secondary cells KW - Electrolysis KW - Phosphorus compounds KW - Ultraviolet spectra KW - Visible spectra AU - Sarah G Stewart AU - John S Newman AB -

This work describes the measurement of the diffusion coefficient in lithium-battery electrolytic solutions. We have adapted the method of restricted diffusion to measure diffusion coefficients of LiPF6 in various solvents using ultraviolet/visible (UV/vis) absorption. The use of UV/vis absorption provides a simple alternative to more arduous experiments and reduces the potential for experimental error due to side reactions. The diffusion coefficient was seen to decrease with concentration according to the following:

D = 3.018 x 10-5 exp(-0.357c) for LiPF6 in acetonitrile and D = 2.582 x 10-5 exp(-2.856c) for LiPF6 in ethylene carbonate/diethyl carbonate (with D in cm2s and c in mol/L). This technique may be useful for any liquid solution with a UV-active species of D greater than 10-6 cm2s.

BT - Journal of The Electrochemical Society DO - 10.1149/1.2801378 IS - 1 LA - eng LB - Batt N2 -

This work describes the measurement of the diffusion coefficient in lithium-battery electrolytic solutions. We have adapted the method of restricted diffusion to measure diffusion coefficients of LiPF6 in various solvents using ultraviolet/visible (UV/vis) absorption. The use of UV/vis absorption provides a simple alternative to more arduous experiments and reduces the potential for experimental error due to side reactions. The diffusion coefficient was seen to decrease with concentration according to the following:

D = 3.018 x 10-5 exp(-0.357c) for LiPF6 in acetonitrile and D = 2.582 x 10-5 exp(-2.856c) for LiPF6 in ethylene carbonate/diethyl carbonate (with D in cm2s and c in mol/L). This technique may be useful for any liquid solution with a UV-active species of D greater than 10-6 cm2s.

PY - 2008 SP - F13 EP - F16 ST - J. Electrochem. Soc. T2 - Journal of The Electrochemical Society TI - The Use of UV/vis Absorption to Measure Diffusion Coefficients in LiPF6 Electrolytic Solutions VL - 155 ER -