Because of their high energy and power densities, lithium-ion batteries have been used as power sources for portable electronic devices such as laptop computers and mobile phones. To characterize the battery, X-ray diffraction is frequently used. Operando XRD measurement, which provides the crystal structure change of the positive and negative electrode materials in the battery during the charge-discharge process, gives important information about the battery, such as reaction state, deterioration characteristics and structural details. Using transmission geometry with a Mo source, it is possible to simultaneously measure changes in the crystal structure of the positive and negative electrode materials of a laminate cell which has a structure similar to what is found in commercial batteries.