ENERGY STORAGE DEVICE AND METHOD

摘要

The purpose of the present invention is to provide an energy storing element whose resistance increase is sufficiently suppressed. To achieve the above purpose, the energy storing element comprises: a first electrode plate; a second electrode plate which has an opposite polarity to the fist electrode plate; and a separator which is placed between the first and the second electrode plates. The first electrode plate includes: a current collecting body; and a medical mixture layer which is stacked on the current collecting body. The medical mixture layer contains: at least one between a binding agent and a conductive assisting agent; a first particle which is formed of an active material; and a secondary particle which is formed of multiple first particles and has a hollow area therein. In the provided energy storing element, at least part of either the binding agent or the conductive assisting agent is placed in the hollow area.