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Volume 7 Biosensors Journal
ISSN: 2090-4967 Electrochemistry 2018
June 11-12, 2018
June 11-12, 2018 | Rome, Italy
4th International Conference on Electrochemistry
Interaction between the morphology and the kinetics of the (de)lithiation reactions of novel SiNW
based anodes in lithium ion batteries
Ulrike Langklotz1 , Andreas Krause2, Walter Weber2 and Alexander Michaelis1, 3
1TU Dresden, Germany
2NaMLab gGmbH, Germany
3Fraunhofer IKTS, Germany
C arbon coated silicon nanowires (SiNW) are the nanostructure of choice for binder-free high capacity anodes. These
anodes with adjusted active mass loading and advanced morphology were grown by chemical vapor deposition (CVD).
The high mass loadings (up to 6 mgSi/cm²) in combination with the lightweight carbon foil used as substrate and current
collector predestines these anodes for applications where high energy densities are required, e.g. for automotive applications.
The requirements in high power devices are especially challenging with respect to the (de)lithiation reactions. Thus, (complex)
carbon coated SiNW anodes with varying morphology and mass loading are examined regarding their performance as well as
the kinetics of the charge-discharge reactions. The specific capacity and cycle stability as well as the achievable C-rates strictly
depend on these parameters. The anodes offer capacities up to 2 mAhcm-2, initial coulomb efficiencies higher than 80% and
capacity fading of less than 10% over 100 cycles. The established process with high uniformity allows detailed examinations
of the charge-discharge curves of samples with tuned properties and clearly shows an effect of the SiNW morphology on the
phase transitions in the initial cycles, which in turn can be crucial regarding the degradation behavior of the anodes. Finally,
galvanostatic intermittent titration technique (GITT) is applied to analyze the charge transfer and diffusion overpotentials of
the (de)lithiation reaction. The overpotentials are basic kinetic parameters of these reactions, and they enable the estimation
of the rate determining processes.
Recent Publications
1. Krause A, Dörfler S, Piwko M, Wisser F M, Jaumann T, Ahrens E, Giebeler L, Althues H, Schädlich S, Grothe J, Jeffery A,
Grube M, Brückner J, Martin J, Eckert J, Kaskel S, Mikolajick T andWeber WM (2016) High area capacity lithium-sulfur
full-cell battery with prelitiathed silicon nanowire-carbon anodes for long cycling stability. Scientific Reports 6:27982.
2. Jaumann T, Balach J, Langklotz U, Sauchuk V, Fritsch M, Michaelis A, Teltevskij V, Mikhailova D, Oswald S, Klose M,
Stephani G, Hauser R, Eckert J and Giebeler L (2017) Lifetime vs. rate capability: understanding the role of FEC and VC
in high energy Li-ion batteries with nano-silicon anodes. Energy Storage Materials 6:26-35.
3. Heubner C, Langklotz U and Michaelis A (2018) Theoretical optimization of electrode design parameters of Si based
anodes for lithium-ion batteries. Journal of Energy Storage 15:181-190.
4. Freitag A, Langklotz U, Rost A, Stamm M and Ionov L (2017) Ionically conductive polymer/ceramic separator for
lithium-sulfur batteries. Energy Storage Materials 9:105-111.
5. Krause A, Grube M, Mikolajick T and Weber W M (2015) Comparison of silicon nanowire growth on SiO2 and on
carbon substrates. ECS Transactions 70:69-78.
Biography
Ulrike Langklotz works in the field of Electrochemistry, mainly for applications in the field of energy storage, for ten years. The general attempt bases on the complementation
of electrochemical results with suitable non-electrochemical measuring methods, e.g. spectroscopy. Main topics are the preparation and characterization of thin dielectric
oxide films as well as the investigation of electrode materials used in lithium ion and lithium sulfur batteries. Recently, the investigation of nanostructured silicon as anode
material was one main topic.
Ulrike Langklotz et al., Biosens J 2018, Volume 7
DOI: 10.4172/2090-4967-C1-002