Surfaces and interfaces in thin-film and conventional li-ion batteries

El capítulo 4 está sujeto a confidencialidad por el autor. 194 p.En esta tesis doctoral titulada "Surfaces and Interfaces in Thin-Film and Conventional Li-ion Batteries" se presentan los resultados del trabajo experimental realizado en relación a materiales del estado del arte en baterías íon-litio. En particular, en una primera parte se describen los resultados obtenidos al estudiar la superficie de electrodos formados por el material Titanato de Litio (Li4Ti5O12, LTO). En esta primera parte el estudio se centra en la evolución de las fases presentes en la superficie del electrodo a lo largo del ciclado electroquímico. En una segunda parte, continuando con los electrodos basados en el material LTO, se estudia el efecto de capas protectoras depositadas en electrodos convencionales mediante la técnica de sputtering. En esta parte se describe el efecto positivo que dichas capas protectoras tienes en el comportamiento electroquímico de los electrodos, al mismo tiempo que se estudia el origen de dicha mejora. Finalmente, en un último capítulo se describe la deposición, caracterización y optimización de electrodos de capa fina del material LiMn1.5Ni0.5O4. Además de una caracterización composicional, morfológica, estructural y electroquímica de los electrodos, se dedica especial atención a las intercaras, tanto la del colector de corriente-electrodo como la del electrodo-electrolito sólido

Current Status and Future Perspective on Lithium Metal Anode Production Methods

Lithium metal batteries (LMBs) are one of the most promising energy storage technologies that would overcome the limitations of current Li-ion batteries, based on their low density (0.534 g cm−3), low reduction potential (−3.04 V vs Standard Hydrogen Electrode) as well as their high theoretical capacities (3860 mAh g−1 and 2061 mAh cm−3). The overall cell mass and volume would be reduced while both gravimetric and volumetric energy densities would be greatly improved. Their electrochemical performance, however, is hampered by the low efficiency at high current densities and continuous degradation, which are related, among other factors, to the properties of the lithium metal anode (LMA). Hence, the production and processing of LMAs is crucial to obtain the desired properties that would enable LMBs. Here, the conventional method used for the production of LMAs, which is the combination of extraction, electrowinning, extrusion, and rolling processes, is reviewed. Then, the advances in the different alternative methods that can be used to produce and improve the properties of LMAs are described, which are divided into vapor phase, liquid phase, and electrodeposition. Within this last method, the anode-less concept, for which different approaches to the development of advanced current collectors are illustrated, is included.I.R.L. acknowledges the support of the Ministerio de Ciencia, Innovación y Universidades (No. PID2019-107468RB-C21) and Gobierno Vasco/Eusko Jaurlaritza (No. IT1546-22). This project has received funding from the Basque Government within the ELKARTEK 2021 call (project CICe2021) under the application number KK-2021/00064