My interest is to develop fundamental understanding and improvement of electrochemical energy storage processes in these type of batteries. With my group I try to achieve this using a broad diversity of experimental probes, recently focusing on operando neutron and X-ray techniques and solid state NMR. With these techniques the aim is reveal the structural, morphological and kinetic properties of battery materials, often during battery (dis)charging, to uncover what limits the performance of next generation battery chemistries. This experimental approach is combined with (ab-initio) simulations from the atomic up to the mesoscopic scale of complete electrodes, both aiming at understanding of the complex interplay of processes, as well as to design new battery materials. The difficulty to investigate processes in batteries, in particular non-invasively and under realistic battery operation condition motivate me to develop experimental approaches using neutron, X-ray and NMR bases techniques. Examples of this are Operando Neutron Depth Profiling, able to determine the Li spatial distribution with high resolution in working electrodes and Micro beam synchrotron diffraction, opening up the possibility to monitor the individual structural transformation of many electrode particles in a battery electrode concurrently, making it possible to gain microscopic insight in what process limits the performance of batteries, the starting points of strategies to improve next generation batteries.