LongLife: in situ conversion alloying anode materials for long lifetime, high-energy density batteries

The LongLife project targets new advanced materials for Li-ion batteries (LIBs) which could be used in future electric vehicles (EVs). The wide deployment of EVs is expected to substantially decrease the emission of greenhouse gases responsible for global climate change. However, the wide adoption of EVs is hindered by performance of modern LIBs. Therefore, the current LIB technology is in active search of new materials with properties capable to deliver the functionalities required by the EV application. These properties include high capacity, long-term stability and ability to operate at high charge/discharge rates. For the last decade, silicon (Si) have been viewed as a promising material for LIB anodes which can bring these capabilities to LIBs. Unfortunately, severe degradation of Si has limited the commercial use of the material. In this project we have looked into the different physical and chemicals mechanisms involved when using silicon-based in-situ conversion alloys as anode material.

LongLife targets the new advanced materials for Li-ion batteries (LIBs) which could be used in future electric vehicles (EV). The wide deployment of EV is expected to substantially decrease the emission of greenhouse gases responsible for global climate change. However, the wide adoption of EVs is hampered by performance of modern LIBs. Therefore, the current LIB technology is in active search of new materials with properties capable to deliver the functionalities required by EV application. These properties include high capacity, long-term stability and ability to operate at high charge/discharge rates. For the last decade, silicon (Si) have been viewed as a promising material for LIB anodes which can bring these capabilities to LIBs, unfortunately, severe degradation of Si limited its application. To address this problem, LongLife aims to develop a new class of Si-based materials which operate on a principle of in situ conversion. Such materials having formula of SiEx (E= N, C) will be prepared by a scalable method of pyrolysis (to be tested in two different reactor architectures). Such approach will ensure a quick adoption of the materials by relevant industries. Furthermore, LongLife will address the fundamental problems of such conversion materials discovered in during early development - low Coulombic efficiency at the first cycle. This will be accomplished by coating of SiEx (E= N, C) nanoparticles with a protective shell and prelithiation. The latter represents a method for delivering extra Li into the battery prior assembly improving the lifetime of the Si-based materials. To support the materials development and to gain the fundamental knowledge the proposed materials will be studied operando - a methods allowing to study the structural changes of the active materials during battery cycling. At the end of the project the materials will be evaluated in complete cells using NMC622 as a cathode.