Secondary battery

The present invention relates to a secondary battery supporting a central portion of an electrode assembly to enhance stability and reliability. For example, disclosed is a secondary battery comprising: an electrode assembly formed by winding a first electrode plate, a separator, and a second electrode plate; a case for accommodating the electrode assembly; a collector plate electrically connected to the first electrode plate and coupled to an upper portion of the electrode assembly; and a core insulating member coupled to a winding center of the electrode assembly at an upper portion of the collector plate, in which the core insulating member includes an insertion portion having an inner hole and a flange portion extending in a horizontal direction from an upper end of the insertion portion. 本发明涉及一种支撑电极组件的中心部分以增强稳定性和可靠性的二次电池。例如，公开了一种二次电池，该二次电池包括：电极组件，通过卷绕第一电极板、隔膜和第二电极板而形成；壳体，用于容纳电极组件；集流板，电连接到第一电极板并且结合到电极组件的上部；以及核心绝缘构件，在集流板的上部处结合到电极组件的卷绕中心，其中，核心绝缘构件包括具有内孔的插入部和从插入部的上端沿水平方向延伸的凸缘部。