TY  - JOUR
AU  - Durmus, Yasin Emre
AU  - Aslanbas, Özgür
AU  - Kayser, Steffen
AU  - Tempel, Hermann
AU  - Hausen, Florian
AU  - de Haart, L. G. J.
AU  - Granwehr, Josef
AU  - Ein-Eli, Yair
AU  - Eichel, Rüdiger-A.
AU  - Kungl, Hans
TI  - Long run discharge, performance and efficiency of primary Silicon–air cells with alkaline electrolyte
JO  - Electrochimica acta
VL  - 225
SN  - 0013-4686
CY  - New York, NY [u.a.]
PB  - Elsevier
M1  - FZJ-2017-00632
SP  - 215 - 224
PY  - 2017
AB  - Si–air batteries, unlike other resource efficient metal–air batteries that were subject of investigations for quite a long time, came to the focus of research only recently. When operated with alkaline electrolyte, severe limitations of the discharge capacities were reported, which were attributed to a passivation layer on the anode. As a consequence, only small fractions of the surface from Si-anodes could be used for discharge. The objective of the present work is to reconsider the discharge behavior of Si–air cells with KOH electrolyte and to point out how a discharge process can be put forward until the complete anode is exhausted. Operating Si–air cells with alkaline electrolyte causes substantial corrosion, which produces also hydrogen gas as a reaction product. Moreover, along with the dissolution of Si in KOH, condensation of silicate structures in the electrolyte has been observed. Both effects accelerate electrolyte loss in the cell. Therefore, appropriately balancing the electrolyte supply of the Si–air cell is a precondition for ongoing discharge. Specifically, cells with As-doped Si-wafer anodes with 0.6 mm and 3.0 mm thickness were discharged in 5 M KOH electrolyte at current densities up to 0.05 mA/cm2 for 260 and 1100 hours, respectively. The drawback is that a minimum amount of electrolyte is required in order not to exceed 4 M Si content, which otherwise leads to a gelation of the electrolyte. Although a considerable fraction of the anode material is not transformed to electrical energy owing to corrosion, specific energies up to 140 Wh/kg (for 1100 h) related to the total anode mass loss were realized.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000393502500024
DO  - DOI:10.1016/j.electacta.2016.12.120
UR  - https://juser.fz-juelich.de/record/826404
ER  -