Typical batteries are composed of several components including an electrolyte, anode, cathode, and a porous separator membrane. Battery characterization involves using various techniques to understand the performance of your design and the unwanted side processes that may occur as these materials interact in operation over a typical lifecycle. Through this analysis, changes to the fabrication and build procedure can be made to optimize the design, yielding a battery suitable for consumer use. For example, atomic force microscopy (AFM) can be applied to image cathode samples and determine the conductive area in post-processing. X-ray photoelectron spectroscopy (XPS) can also be used to determine what elements are present in a sample and to find interfering impurities so the pathway to their introduction can be mitigated.