To provide a highly reliable power storage device. To provide a long-life power storage device. To provide a power storage device electrode having high adhesion with a current collector. To reduce or inhibit electrochemical decomposition of an electrolytic solution or the like on a surface of an electrode. The power storage device electrode includes a current collector and a second electrode layer provided over the current collector and including a second binder and an active material. A first electrode layer including a first binder and conductive particles is provided between the current collector and the second electrode layer. At least part of a surface of the active material is provided with a coating film, and the coating film is porous.