Since Sony introduced the Lithium Ion Battery (LIB) in 1991, an enormous effort has been made to further improve the performance of this battery system[1-2]. Nowadays, the research in LIBs is driven by the transition from combustion-based transportation to electric engines and the global energy revolution[3-5]. Environmental friendly cell chemistries are thus of particular interest in terms of recycling and safety reasons, especially for storage of renewable energies. In this connection, dual-graphite batteries receive increasing attention due to the use of graphitic carbon for both the negative and positive electrodes, i.e., free of transition metals[6]. A prerequisite for further improvements is clearly the understanding of the ongoing chemistry in these complex systems. In the last years, solid-state Nuclear Magnetic Resonance (NMR) has proven to be a very powerful technique for the investigation of the underlying chemistry of a vast number of materials used in LIBs[7-8]. Since NMR is not restricted to crystalline samples also highly disordered and amorphous materials can be studied. Furthermore, solid-state NMR provides quantitative measurements, is chemically specific and therefore extremely suitable for the investigation of the electrochemical processes in battery systems[7-8]. Also, the recent development of in situ or in operando measurements makes it highly beneficial for battery research[7-9]. In this contribution, we present the (i) first 119Sn NMR spectroscopic characterization of the Li-Sn system for the subsequent determination of Sn-containing battery materials, (ii) in operando determination of high surface area lithium (HSAL) on lithium metal electrodes, (iii) investigations of the charge/discharge mechanisms in S/PAN, and finally (iv) insights in the anion intercalation in dual-graphite cells.