| Autor: |
Kazi Rakib Ahmed, Mihri Ozkan, Cengiz Ozkan |
| Rok vydání: |
2015 |
| Zdroj: |
ECS Meeting Abstracts. :1728-1728 |
| ISSN: |
2151-2043 |
| DOI: |
10.1149/ma2015-01/30/1728 |
| Popis: |
Electrochemical impedance spectroscopy has been used to investigate rate-limiting conditions in commercial LiCoO2 cathodes. The insights gained may be extended to most lithium-ion battery systems. In general, two possible rate-limiting conditions may exist in a lithium-ion battery - i) diffusion limited, and ii) electron exchange-rate limited. In the former case, rate of diffusion (of ions) is slower than that of redox reactions occurring at active material surface - leading to a negative concentration gradient (of ions) toward the electrode surface for cathodic reactions. In the latter case, a positive concentration gradient persists toward the electrode surface for cathodic reactions. Insights into electrical equivalent circuits derived via electrochemical impedance spectroscopy have led to novel ways of recognizing the rate-limiting behavior in LiCoO2 half-cell. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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