This title appears in the Scientific Report :
2018
Please use the identifier:
http://dx.doi.org/10.1016/j.jpowsour.2017.11.049 in citations.
Modeling the degradation mechanisms of C$_{6}$/LiFePO$_{4}$ batteries
Modeling the degradation mechanisms of C$_{6}$/LiFePO$_{4}$ batteries
A fundamental electrochemical model is developed, describing the capacity fade of C$_{6}$/LiFePO$_{4}$ batteries as a function of calendar time and cycling conditions. At moderate temperatures the capacity losses are mainly attributed to Li immobilization in Solid-Electrolyte-Interface (SEI) layers...
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Personal Name(s): | Li, Dongjiang |
---|---|
Danilov, Dmitri / Zwikirsch, Barbara / Fichtner, Maximilian / Yang, Yong / Eichel, Rüdiger-A. / Notten, Peter H. L. (Corresponding author) | |
Contributing Institute: |
Grundlagen der Elektrochemie; IEK-9 |
Published in: | Journal of power sources, 375 (2018) S. 106 - 117 |
Imprint: |
New York, NY [u.a.]
Elsevier
2018
|
DOI: |
10.1016/j.jpowsour.2017.11.049 |
Document Type: |
Journal Article |
Research Program: |
Electrochemical Storage |
Publikationsportal JuSER |
A fundamental electrochemical model is developed, describing the capacity fade of C$_{6}$/LiFePO$_{4}$ batteries as a function of calendar time and cycling conditions. At moderate temperatures the capacity losses are mainly attributed to Li immobilization in Solid-Electrolyte-Interface (SEI) layers at the anode surface. The SEI formation model presumes the availability of an outer and inner SEI layers. Electron tunneling through the inner SEI layer is regarded as the rate-determining step. The model also includes high temperature degradation. At elevated temperatures, iron dissolution from the positive electrode and the subsequent metal sedimentation on the negative electrode influence the capacity loss. The SEI formation on the metal-covered graphite surface is faster than the conventional SEI formation. The model predicts that capacity fade during storage is lower than during cycling due to the generation of SEI cracks induced by the volumetric changes during (dis)charging. The model has been validated by cycling and calendar aging experiments and shows that the capacity loss during storage depends on the storage time, the State-of-Charge (SoC), and temperature. The capacity losses during cycling depend on the cycling current, cycling time, temperature and cycle number. All these dependencies can be explained by the single model presented in this paper. |