ELECTRODE ACTIVE MATERIAL FOR ELECTROCHEMICAL ELEMENTS, ELECTRODE MATERIAL FOR ELECTROCHEMICAL ELEMENTS, ELECTRODE FOR ELECTROCHEMICAL ELEMENTS, ELECTROCHEMICAL ELEMENT, AND MOBILE OBJECT

Provided are an electrochemical element having excellent load characteristics, an electrode active material, an electrode material, and an electrode that can constitute the electrochemical element, and a movable body including the electrochemical element. An electrode active material for an electrochemical element according to the present invention is a monoclinic niobium complex oxide, and Db/Da is 1.5 or more, where Da is a crystallite size in the a-axis direction, and Db is a crystallite size in the b-axis direction. An electrode material for an electrochemical element according to the present invention contains the electrode active material for an electrochemical element according to the present invention. An electrode for an electrochemical element according to the present invention contains the electrode active material for an electrochemical element according to the present invention or the electrode material for an electrochemical element according to the present invention. In an electrochemical element according to the present invention, either one of a positive electrode and a negative electrode is the electrode for an electrochemical element according to the present invention. A movable body according to the present invention includes the electrochemical element according to the present invention.