Abstract: A filter module for a gravity-based water purification device is provided. A filter module for a gravity-based water purification device, according to one embodiment of the present invention, comprises: a support frame including a loop-shaped edge member, which includes an empty space of which both sides are open, and a dividing member, which is coupled to the edge member so as to enable the empty space to be divided into a plurality of storage spaces; a pair of filtering members which are formed in a plate shape having a predetermined area, and which are coupled to the support frame so as to enable filtered water to be produced from raw water moving from the outside toward the plurality of storage spaces; and water-collecting ports for discharging, to the outside, the filtered water stored in the plurality of storage spaces, wherein the plurality of storage spaces communicate with each other through at least one communication passage formed at the dividing member.

Abstract: A lithium secondary battery includes a cathode formed from a cathode active material including a first cathode active material particle and a second cathode active material particle, an anode and a separator interposed between the cathode and the anode. The first cathode active material particle includes a lithium metal oxide including a continuous concentration gradient in at least one region between a central portion and a surface portion. The second cathode active material particle includes a lithium metal oxide including elements the same as those of the first cathode active material particle, and the second cathode active material particle has a uniform composition from a central portion to a surface.

Abstract: A connecting device is provided that includes a movable part contacting an external contact terminal, and an elastic part connected to the movable part and configured to provide an elastic force enabling movement of the movable part. The connecting device also includes a support connected to the elastic part, and at least one protecting wall connected to the support and configured to protect the movable part from external forces. The connecting device further includes an extension extending from the at least one protecting wall in a direction along which the movable part moves and configured to bring the movable part close to the external contact terminal, and a base part provided within the extension and configured to reinforce the support.

Abstract: A connecting device is provided that includes a movable part contacting an external contact terminal, and an elastic part connected to the movable part and configured to provide an elastic force enabling movement of the movable part. The connecting device also includes a support connected to the elastic part, and at least one protecting wall connected to the support and configured to protect the movable part from external forces. The connecting device further includes an extension extending from the at least one protecting wall in a direction along which the movable part moves and configured to bring the movable part close to the external contact terminal, and a base part provided within the extension and configured to reinforce the support.