Conclusions Producing Si microwire anodes out of macroporous Si is a fully scalable process. Mainly, the current for the electrochemical

processes has to be scaled according to the desired area of the anodes. Having longer wires enables the storage of CDK inhibitor larger amount of charge per area (areal capacity), while larger anode areas represent larger amounts of active material and thus higher total capacities. Scaling up the capacity pays, however, with a demerit in the performance of the anodes. Due to diffusion limitation of Li when scaling up the length of the wires, the capacity fades monotonically when cycling at high rates. On the other hand, the amount of Li necessary for the formation of the solid electrolyte interface scales up with the scaling factor. Authors’ information EQG is MK-2206 mouse a professor for materials science at the University of Puebla. He led the project for the development of high capacity Si wire anodes for Li ion batteries at the University of Kiel (‘general materials science’ group) until 2013. He is also a specialist in the synthesis and characterization of photoactive materials and microstructured electrodes for Li ion batteries. JC is a senior scientist in materials science. Since 1993, he coordinates

A-1210477 datasheet the academic and scientific activities of the ‘general materials science’ group of the Institute for Materials Science of the University of Kiel. He is an expert in electrochemical pore etching in semiconductors, FFT impedance spectroscopy, and general characterization of solar cells.

HF is a professor for materials science at the University of Kiel. He is the leader of the ‘general materials science’ group of the Institute for Materials Science. He is one of the co-finders of the electrochemical etching process of pores in n-type Si in 1990. His expertise includes silicides, electrochemical processes with semiconductors, and solar cells. Acknowledgements The authors acknowledge the German Federal Ministry of Education and Research (BMBF) for the economical support provided through the ‘AlkaSuSi’ project. The company Siltronic AG is also gratefully acknowledged for providing us Si wafers for the experiments. References 1. Chan CK, Peng H, Liu G, McIlwrath K, Zhang Sunitinib order XF, Huggins RA, Cui Y: High-performance lithium battery anodes using silicon nanowires. Nat Nanotechnol 2008, 3:31–35. 10.1038/nnano.2007.411CrossRef 2. Quiroga-González E, Carstensen J, Föll H: Good cycling performance of high-density arrays of Si microwires as anodes for Li ion batteries. Electrochim Acta 2013, 101:93–98.CrossRef 3. Kang K, Lee HS, Han DW, Kim GS, Lee D, Lee G, Kang YM, Jo MH: Maximum Li storage in Si nanowires for the high capacity three-dimensional Li-ion battery. Appl Phys Lett 2010, 96:053110–1-053110–3. 4. Yang Y, McDowell MT, Jackson A, Cha JJ, Hong SS, Cui Y: New nanostructured Li 2 S/silicon rechargeable battery with high specific energy.