The application of the energy dispersive X-ray diffraction (EDXD) technique to in situ structural measurements on battery materials is shown for the first time. EDXD may present a promising alternative for this kind of measurement to the traditional diffractometric technique, even when the synchrotron radiation is used. The merits and drawbacks of this method are discussed, with particular attention to the solution of the X-ray absorption problem that, reducing the signal intensity, imposes the use of specifically designed cells. Finally, preliminary results obtained in the study of a typical commercial cathodic material for Li-ion batteries (i.e., LiNi0.8Co0.2O2) are reported.