▎ 摘 要
NOVELTY - A secondary battery comprises a positive electrode (570a) and a negative electrode (570b). The negative electrode contains an active material (581), an active material (582), and a graphene compound (583). At least a portion of the surface of the active material (581) has a region covered with the active material (582). The surface of the active material (582) and at least a portion of the surface of the active material (581) have a region covered with the graphene compound. The active material (581) contains graphite and the active material (582) contains silicon. The capacity of the positive electrode is 50-100% with respect to the capacity of the negative electrode. USE - Secondary battery e.g. lithium ion secondary battery used for vehicle, electrical storage system and electronic devices (all claimed). Uses include but are not limited to mobile phones, smartphones, notebook computers, portable music players, digital cameras, medical devices, hybrid vehicles, electric vehicles and plug-in hybrid vehicles. ADVANTAGE - The secondary battery is highly safe and has less deterioration, high energy density, and contains mechanically durable negative and positive electrode having less deterioration and high capacity. DESCRIPTION OF DRAWING(S) - The drawings show a cross-sectional view of the electrodes. Negative electrode (570a) Positive electrode (570b) Negative electrode current collector (571a) Positive electrode current collector (571b) Active material (581, 582) Graphene compound (583)