Electrochemistry plays a significant role in energy conversion and storage technologies, such as lithium ion batteries (LIBs) and microbial fuel cells (MFCs). Specifically, LIBs are constructed using billions of individual battery particles, which store (or generate) the electrical energy by forming (or breaking) the chemical bonds with lithium ions within the particle. MFCs are also the electrochemical devices consisting of the bio-electrodes where billions of microorganisms convert high-energy chemical bonds to electrical energy. For these applications, the electrochemical kinetics or thermodynamics of the individual bacterium or battery primary particle defines the fundamental limit of the devices, and further governs the overall performance. However, due to the porous and heterogeneous nature of these electrodes, the conventional current-voltage measurement on these ensembles shows the certain limit in untangling complexity and heterogeneity of electrochemistry. Here, in my talk, I will introduce the electrochemical platform where synchrotron-based spectromicroscopy (or optical microscopy) and electrochemical microfluidic cells are combined to investigate the charge transfer mechanism at a single bacterium or a single primary battery particle. The detailed spatiodynamics within battery particles gained from this platform will be highlighted.