The commercialization of Li-ion batteries in 1991 was the culmination of in-depth R&D conducted by scientists and engineers around the globe over the preceding few decades. Further development of Li-ion batteries and alternative rechargeable batteries has continued until today. As the world is rapidly moving towards a new era defined by green technologies, more practical and accurate R&D is required in order to meet the increasing demands for energy storage systems, specifically from the automotive industry. This white paper presents the basics of the Li-ion battery technology and guides the reader through the relevant techniques and terminologies in Li-ion battery research.