LiBEST

Motivation

In recent years lithium-ion battery technology has gained much attention but with currently used active materials a further enhancement of its capacity is limited. Therefore, research has originated many different materials for both anode and cathode side which exhibit high specific capacities. However, the implementation of these new materials remains difficult because they encompass a number of challenges. Within this project two promising anode materials (silicon carbon composites, lithium metal) including a thereon optimized electrolyte as well as an electrolyte system for sulphur based cathodes are going to be investigated. The main goal is to build a lithium ion battery with good electrochemical performance and high safety characteristics by controlling the electrolyte composition, the structure and surface characteristics of the particles.

Project description

Within the project, the iPAT deals with the preparation of silicon nanoparticles and silicon graphite composite particles. Silicon nanoparticles are prepared by grinding in stirred media mills. The use of ground silicon nanoparticles (x50 ≤ 150 nm) is beneficial towards larger particles because the absolute volumetric expansion of silicon during lithiation is a function of particle size. The granulations are performed by high-shear mixing and fluidized bed granulation. Within both processes the beforehand produced silicon nanoparticles are deposited on the surface of coarser graphite particles. The resulting composite structure has a major impact on the mechanical stability and electrochemical performance of the electrode. Therefore, the influence of process parameters and granule composition (granule binder, conductive additive) on structural, mechanical, electrical and electrochemical properties are investigated.

Contact:

Jannes Müller
jannes.mueller(at)tu-braunschweig.de