NANOSCALE MAPPING OF LOCAL ELECTROCHEMICAL BEHAVIOR IN NANOCOMPOSITES
PhD Student: Daniel Monteiro Cunha
Supervisor: Mark Huijben
The aim of this project is to provide insight into the elementary mechanisms of solid-state electrochemical processes within the oxide electrode/electrolyte nanocomposites at the nanoscale.
Lithium-ion batteries are the most popular rechargeable batteries nowadays. However, most commercial rechargeable Li-ion batteries deliver energy densities of only 10-15% of their theoretical values1,2 and start to fade (irreversible capacity loss) after only hundreds of operational cycles3. Limitations include slow electrode process kinetics, low ionic diffusion and low electronic conductivity, especially at the electrode-electrolyte interfaces. Gaining control over these interfaces is a grand challenge, being more important than designing new materials4.
The Electrochemical Strain Microscopy (ESM) technique will provide information about the lithium diffusion mechanism in 3D self-assembled solid-state battery structures. With high-resolution mapping the possible concentration of lithium ion flow along grain boundaries, which could lead to cracking and battery failure, will be studied.
In this project, detailed understanding of the interfacial reactions in the nanocomposites will provide insight into the causes of the loss of capacity on subsequent battery charging/discharging or battery fading, leading to knowledge-driven design and optimization of 3D solid-state lithium batteries.
1 F. Cheng, J. Liang, Z. Tao, and J. Chen, Adv. Mater. 23, 1695-1715 ( 2011), DOI: 10.1002/adma.201003587
2 J.F.M. Oudenhoven, R.J. Vullers, and R. van Schaijk, Int. J. Energy Res. 36, 1139 (2012), DOI: 10.1002/er.2949
3 M. Armand, J.M. Tarascon, Nature 451, 652 (2008), DOI:10.1038/451652a
4 J.-M. Tarascon, and M. Armand, Nature 414, 359 (2001), DOI: 10.1038/35104644