The ever-increasing demand for high-performing, economical, and safe power storage for portable electronics and electric vehicles stimulates R&D in the field of chemical power sources. In the past two decades, lithium-ion technology has proven itself a most robust technology, which delivers high energy and power capabilities. At the same time, current technology requires that the energy and power capabilities of Li-ion batteries be ‘beefed up’ beyond the existing state of the art. Increasing the battery voltage is one of the ways to improve battery energy density; in Li-ion cells, the objective of current research is to develop a 5-volt cell, and at the same time to maintain high specific charge capacity, excellent cycling, and safety. Since current anode materials possess working potentials fairly close to the potential of a lithium metal, the focus is on the development of cathode materials. This work reviews and analyzes the current state of the art, achievements, and challenges in the field of high-voltage cathode materials for Li-ion cells. Some suggestions regarding possible approaches for future development in the field are also presented.