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Comment on “Out‐of‐Cell Oxygen Diffusivity Evaluation in Lithium–Air Batteries” by He et al.
Author(s) -
Corti Horacio R.,
Cortés Páez Henry Andrés
Publication year - 2017
Publication title -
chemelectrochem
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.182
H-Index - 59
ISSN - 2196-0216
DOI - 10.1002/celc.201600524
Subject(s) - thermal diffusivity , cathode , oxygen , electrochemistry , battery (electricity) , electrolyte , oxygen transport , lithium (medication) , oxygen sensor , diffusion , materials science , analytical chemistry (journal) , chemistry , chemical engineering , thermodynamics , electrode , chromatography , physics , engineering , medicine , power (physics) , organic chemistry , endocrinology
In a recent paper, He et al. ( ChemElectroChem 2014 , 1 , 2052–2057) described a methodology for measuring out‐of‐cell oxygen diffusivity in lithium–air battery (LAB) cathodes, combining an electrochemical device with a classical gas‐transport model. We will demonstrate here that the authors erroneously assumed that the Knudsen diffusivity of gaseous oxygen in the porous cathode is smaller than the diffusivity in the electrolyte and, consequently, that the oxygen mass transport would limit the current output of the battery. Therefore, it is impossible to determine the oxygen diffusivity in LAB cathodes by using the electrochemical device proposed by the authors, comprising an oxygen pump, the LAB cathode, and an oxygen sensor.