Abstract
To study the filming mechanism of graphite-based LiC{sub n} electrodes, electrochemical reduction of graphite materials was carried out in 1 M LiClO{sub 4}/ethylene carbonate (EC)-1,2-dimethoxyethane (DME) (1:1 by volume). Due to film forming a peak at potentials around 0.8 V versus Li/Li{sup +} was observed during the first reduction. The reversibility of this peak was examined by cyclic voltammetry; in addition, the crystal expansion/contraction was checked by means of dilatometry. The results indicate that ternary solvated graphite-intercalation compounds (GICs) were formed at those potentials leading to drastic expansion of the graphite matrix (>150%). These Li(EC){sub y1}(DME){sub y2}C{sub n}-GICs decompose and build up a protective layer on the graphite that prevents further solvent co-intercalation. The beneficial effect of EC-containing electrolytes on the stability of lithium-carbon anodes seems to be related to inorganic films formed via secondary chemical decomposition of electrochemically formed EC-GICs. The key-role of inorganic films is also demonstrated by the fact that inorganic additives, such as carbon dioxide, suppress the formation of solvated GICs. Furthermore, it can be seen that lithium-carbon negatives can even be operated in inorganic electrolytes such as SO{sub 2} and SOCl{sub 2}. (orig.)
Besenhard, J O;
[1]
Winter, M;
[1]
Yang, J;
[1]
Biberacher, W
[2]
- Inst. fuer Chemische Technologie Anorganischer Stoffe, Technische Univ., Graz (Austria)
- Walther-Meissner-Inst. fuer Tieftemperaturforschung, Garching (Germany)
Citation Formats
Besenhard, J O, Winter, M, Yang, J, and Biberacher, W.
Filming mechanism of lithium-carbon anodes in organic and inorganic electrolytes.
Switzerland: N. p.,
1995.
Web.
doi:10.1016/0378-7753(94)02073-C.
Besenhard, J O, Winter, M, Yang, J, & Biberacher, W.
Filming mechanism of lithium-carbon anodes in organic and inorganic electrolytes.
Switzerland.
https://doi.org/10.1016/0378-7753(94)02073-C
Besenhard, J O, Winter, M, Yang, J, and Biberacher, W.
1995.
"Filming mechanism of lithium-carbon anodes in organic and inorganic electrolytes."
Switzerland.
https://doi.org/10.1016/0378-7753(94)02073-C.
@misc{etde_123073,
title = {Filming mechanism of lithium-carbon anodes in organic and inorganic electrolytes}
author = {Besenhard, J O, Winter, M, Yang, J, and Biberacher, W}
abstractNote = {To study the filming mechanism of graphite-based LiC{sub n} electrodes, electrochemical reduction of graphite materials was carried out in 1 M LiClO{sub 4}/ethylene carbonate (EC)-1,2-dimethoxyethane (DME) (1:1 by volume). Due to film forming a peak at potentials around 0.8 V versus Li/Li{sup +} was observed during the first reduction. The reversibility of this peak was examined by cyclic voltammetry; in addition, the crystal expansion/contraction was checked by means of dilatometry. The results indicate that ternary solvated graphite-intercalation compounds (GICs) were formed at those potentials leading to drastic expansion of the graphite matrix (>150%). These Li(EC){sub y1}(DME){sub y2}C{sub n}-GICs decompose and build up a protective layer on the graphite that prevents further solvent co-intercalation. The beneficial effect of EC-containing electrolytes on the stability of lithium-carbon anodes seems to be related to inorganic films formed via secondary chemical decomposition of electrochemically formed EC-GICs. The key-role of inorganic films is also demonstrated by the fact that inorganic additives, such as carbon dioxide, suppress the formation of solvated GICs. Furthermore, it can be seen that lithium-carbon negatives can even be operated in inorganic electrolytes such as SO{sub 2} and SOCl{sub 2}. (orig.)}
doi = {10.1016/0378-7753(94)02073-C}
journal = []
issue = {2}
volume = {54}
journal type = {AC}
place = {Switzerland}
year = {1995}
month = {Apr}
}
title = {Filming mechanism of lithium-carbon anodes in organic and inorganic electrolytes}
author = {Besenhard, J O, Winter, M, Yang, J, and Biberacher, W}
abstractNote = {To study the filming mechanism of graphite-based LiC{sub n} electrodes, electrochemical reduction of graphite materials was carried out in 1 M LiClO{sub 4}/ethylene carbonate (EC)-1,2-dimethoxyethane (DME) (1:1 by volume). Due to film forming a peak at potentials around 0.8 V versus Li/Li{sup +} was observed during the first reduction. The reversibility of this peak was examined by cyclic voltammetry; in addition, the crystal expansion/contraction was checked by means of dilatometry. The results indicate that ternary solvated graphite-intercalation compounds (GICs) were formed at those potentials leading to drastic expansion of the graphite matrix (>150%). These Li(EC){sub y1}(DME){sub y2}C{sub n}-GICs decompose and build up a protective layer on the graphite that prevents further solvent co-intercalation. The beneficial effect of EC-containing electrolytes on the stability of lithium-carbon anodes seems to be related to inorganic films formed via secondary chemical decomposition of electrochemically formed EC-GICs. The key-role of inorganic films is also demonstrated by the fact that inorganic additives, such as carbon dioxide, suppress the formation of solvated GICs. Furthermore, it can be seen that lithium-carbon negatives can even be operated in inorganic electrolytes such as SO{sub 2} and SOCl{sub 2}. (orig.)}
doi = {10.1016/0378-7753(94)02073-C}
journal = []
issue = {2}
volume = {54}
journal type = {AC}
place = {Switzerland}
year = {1995}
month = {Apr}
}