Abstract: This application relates to an energy storage device. In one embodiment, the energy storage device includes an electrode unit including first and second current collectors that are separated by a separator, first and second terminals respectively connected to the first and second current collectors and a case accommodating the electrode unit. The energy storage device also includes a flexible closure covering the case and having first and second through-holes passing therethrough and exposing the first and second terminals to the environment, wherein the flexible closure contains about 15 wt % or less of SiO2. According to some embodiments, since the weight percentage of SiO2 is significantly reduced and thus, the amount and degree of the SiO2 reduction significantly decreases, a structural deformation of the flexible closure at a microscopic level is minimized. Accordingly, a wetting phenomenon is significantly reduced, and thus the life span of an energy storage device significantly increases.

Abstract: This application relates to an energy storage device. In one embodiment, the energy storage device includes an electrode unit including first and second current collectors that are separated by a separator, first and second terminals respectively connected to the first and second current collectors and a case accommodating the electrode unit. The energy storage device also includes a flexible closure covering the case and having first and second through-holes passing therethrough and exposing the first and second terminals to the environment, wherein the flexible closure contains about 15 wt % or less of SiO2. According to some embodiments, since the weight percentage of SiO2 is significantly reduced and thus, the amount and degree of the SiO2 reduction significantly decreases, a structural deformation of the flexible closure at a microscopic level is minimized. Accordingly, a wetting phenomenon is significantly reduced, and thus the life span of an energy storage device significantly increases.

Abstract: Disclosed herein is an electric double layer device including a urethane potting unit (50) for filling the gap between a portion of a first terminal (21) that is exposed out of a rubber cap (40) and a first through hole (41) and the gap between a portion of a second terminal (22) that is exposed out of the rubber cap and a second through hole (42), wherein an aluminum terminal (A) constituting each of the first terminal (21) and the second terminal (22) is anodized such that an aluminum oxide film (Al) is formed on the aluminum terminal, whereby the lifespan of the electric double layer device is relatively increased.

Abstract: Disclosed herein is an electric double layer device including a urethane potting unit (50) for filling the gap between a portion of a first terminal (21) that is exposed out of a rubber cap (40) and a first through hole (41) and the gap between a portion of a second terminal (22) that is exposed out of the rubber cap and a second through hole (42), wherein an aluminum terminal (A) constituting each of the first terminal (21) and the second terminal (22) is anodized such that an aluminum oxide film (Al) is formed on the aluminum terminal, whereby the lifespan of the electric double layer device is relatively increased.