Effects of Cell Geometry on Rate Performance of Secondary Batteries

Tuesday, 3 October 2017: 16:20
Maryland D (Gaylord National Resort and Convention Center)


3D geometries for microbattery applications have been explored to increase capacity per footprint area, relevant for small footprint area micro devices [1] [2]. Simulations of interdigitated Li-ion batteries suggest 4 orders of magnitude increase in areal capacity at 330 C-rate from 0.58 Ah/m2in the conventional geometry to 318 Ah/m2 for the 3D geometry [3]. Realization of practical 3D battery designs can potentially decouple their power and energy [4], properties that are historically coupled in conventional battery design, which might have significant implications for high power devices.

Using commonly found commercially available materials and tools, we designed and conducted a simple experiment to elucidate how battery performance can be improved by varying the relative arrangements of the active and inactive components. Examples include using Li/LiCoO2 2032-type coin cells with 1M LiPF6 and carbonate containing electrolytes. The maximum active ion diffusion length required to fully delithiate the LiCoO2 electrodes during cycling was increased by 400-6500 μm compared with standard reference cells, and the effect on rate performance was measured between C/24 and C/3. Results suggest that extending the maximum active ion diffusion path length by >1600 μm still allows for attaining specific capacity that matches that of the reference cell at C/24. We discuss possible new geometries and optimized designs in the framework of battery performance.

[1] C. Liu, E.I. Gillette, X. Chen, A.J. Pearse, A.C. Kozen, M.A. Schroeder, K.E. Gregorczyk, S.B. Lee, G.W. Rubloff. Nature Nanotechnology 9 (2014) 1031-1039.
[2] T.S. Arthur, D.J. Bates, N. Cirigliano, D.C. Johnson, P. Malati, J.M. Mosby, E. Perre, M.T. Rawls, A.L. Prieto, B.Dunn. MRS Bulletin 36 (2011) 523-531.
[3] D. Miranda, C.M. Costa, A.M. Almeida, S. Lanceros-Méndez. Applied Energy 165 (2016) 318-328.
[4] N. Cirigliano, G. Sun, D. Membreno, P. Malati, C.J. Kim, B. Dunn. Energy Technology 2 (2014) 362-369.