TY - JOUR
T1 - Redox Probing Study of the Potential Dependence of Charge Transport Through Li2O2
AU - Knudsen, Kristian Bastholm
AU - Luntz, Alan C.
AU - Jensen, Søren Højgaard
AU - Vegge, Tejs
AU - Hjelm, Johan
PY - 2015
Y1 - 2015
N2 - In the field of energy storage devices the pursuit for cheap,
high energy density, reliable secondary batteries is at the top of the agenda.
The Li−O2 battery is one of the possible technologies that, in theory, should
be able to close the gap, which exists between the present state-of-the-art Liion
technologies and the demand placed on batteries by technologies such as
electrical vehicles. Here we present a redox probing study of the charge
transfer across the main deposition product lithium peroxide, Li2O2, in the
Li−O2 battery using outer-sphere redox shuttles. The change in
heterogeneous electron transfer exchange rate as a function of the potential
and the Li2O2 layer thickness (∼depth-of-discharge) was determined using
electrochemical impedance spectroscopy. The attenuation of the electron
transfer exchange rate with film thickness is dependent on the probing
potential, providing evidence that hole transport is the dominant process for
charge transfer through Li2O2 and showing that the origin of the sudden death observed upon discharge is due to charge transport limitations.
AB - In the field of energy storage devices the pursuit for cheap,
high energy density, reliable secondary batteries is at the top of the agenda.
The Li−O2 battery is one of the possible technologies that, in theory, should
be able to close the gap, which exists between the present state-of-the-art Liion
technologies and the demand placed on batteries by technologies such as
electrical vehicles. Here we present a redox probing study of the charge
transfer across the main deposition product lithium peroxide, Li2O2, in the
Li−O2 battery using outer-sphere redox shuttles. The change in
heterogeneous electron transfer exchange rate as a function of the potential
and the Li2O2 layer thickness (∼depth-of-discharge) was determined using
electrochemical impedance spectroscopy. The attenuation of the electron
transfer exchange rate with film thickness is dependent on the probing
potential, providing evidence that hole transport is the dominant process for
charge transfer through Li2O2 and showing that the origin of the sudden death observed upon discharge is due to charge transport limitations.
U2 - 10.1021/acs.jpcc.5b08757
DO - 10.1021/acs.jpcc.5b08757
M3 - Journal article
SN - 1932-7447
VL - 119
SP - 28292
EP - 28299
JO - The Journal of Physical Chemistry Part C
JF - The Journal of Physical Chemistry Part C
IS - 51
ER -