In situ reflection absorption FTIR spectroscopy (in situ FTIR) and small spot X-ray electron emission spectroscopy (XPS) of emersed electrodes were used to examine the electrochemical double layer on glassy carbon (GC) and the anodic storage reactions of the zinc bromine battery which are the formation of a non-aqueous N-methyl-ethyl-pyrrolidinium (MEP+) and/or N-methyl-ethyl-morpholinium (MEM+) polybromide phase. Oxidative conversion of the GC surface to COH, CO and COO− is observed during potential cycling between the hydrogen and oxygen evolution. The extrapolation of the intensity of the bending vibration signal due to adsorbed water allowed the determination of the point of zero charge (pzc). The pzc of GC is more than 1 V more negative than that of gold in the presence of MEP-Br or MEM-Br. Above the pzc, up to the bromide oxidation potential, MEM+ shows a much stronger chemical affinity to GC than MEP+ because the MEM morpholinium bridge oxygen shows a stronger interaction with the oxidised carbon surface species than the pure CH-structure of the pyrrolidinium species. This study suggests that the battery charging reaction involves mainly a heterogeneous electron transfer from Br− followed by a homogeneous chemical reaction leading to MEP-polybromide, whereas the conversion of specifically adsorbed MEM-Br ion pairs to polybromide is a slow process.