The present invention relates to a separator for electrochemical elements, the separator comprising synthetic fibers and beaten cellulose fibers, wherein the beaten cellulose fibers have a Canadian standard freeness measured in accordance with JIS P 8121 of 50 ml or more and 500 ml or less, and in a fiber diameter distribution histogram of the beaten cellulose fibers, (1) the fibers have a maximum frequency peak in a range of 50 μm or less, and (2) a ratio of the fibers having a fiber diameter of 20 μm or less is 55% or more.

An electrochemical device includes electrode plates and a separation layer formed on a surface of an electrode plate. The separation layer includes a porous layer formed on the surface of the electrode plate. The porous layer includes nanofibers. It takes 15 seconds or less for an electrolytic solution to infiltrate into the separation layer. The separation layer exhibits functions of a separator. Therefore, the electrochemical device achieves at least a relatively high energy density without using a stand-alone separator.

An electrochemical device includes electrode plates and a separation layer formed on a surface of an electrode plate. The separation layer includes a porous layer formed on the surface of the electrode plate. The porous layer includes nanofibers. It takes 15 seconds or less for an electrolytic solution to infiltrate into the separation layer. The separation layer exhibits functions of a separator. Therefore, the electrochemical device achieves at least a relatively high energy density without using a stand-alone separator.

An electrochemical device includes an electrode plate and a separation layer on at least one surface of the electrode plate. The separation layer includes a nanofibrous porous substrate including nanofibers and polymer particles distributed in the nanofibrous porous substrate including nanofibers. A melting temperature of the polymer particles is 70° C. to 150° C.

A battery separator configured for reducing acid stratification for an enhanced flooded battery. The battery separator for the enhanced flooded battery is configured to minimize acid stratification. The battery separator is comprised of a microporous membrane and an absorptive mat. The absorptive mat includes a 3-hour wicking height greater than 15 cm. Wherein the absorptive mat of the battery separator is configured to minimize acid stratification of the enhanced flooded battery.

A battery separator configured for reducing acid stratification for an enhanced flooded battery. The battery separator for the enhanced flooded battery is configured to minimize acid stratification. The battery separator is comprised of a microporous membrane and an absorptive mat. The absorptive mat includes a 3-hour wicking height greater than 15 cm. Wherein the absorptive mat of the battery separator is configured to minimize acid stratification of the enhanced flooded battery.

Disclosed are a separator that includes fibrils including a polyolefin; and bond structures generated by reacting at least some of a first radical formed on surfaces of the fibrils by a photoreactive material and a second radical formed in the photoreactive material, and a method of manufacturing the separator.

Disclosed are a separator that includes fibrils including a polyolefin; and bond structures generated by reacting at least some of a first radical formed on surfaces of the fibrils by a photoreactive material and a second radical formed in the photoreactive material, and a method of manufacturing the separator.

According to one embodiment, an electrospinning apparatus deposits a fiber on an electrode. The apparatus includes a transport section and a fiber deposition section. The transport section transports electrodes. The fiber deposition section deposits the fiber on first and second surfaces of the electrodes. The electrodes include coated and uncoated portions. The transport section transports the electrodes in a third direction in the fiber deposition section. The electrodes include first and second electrodes. The first electrode is positioned at one end in the second direction and transported so that the uncoated portion of the first electrode protrudes toward the one end side. The second electrode is positioned at other end in the second direction and transported so that the uncoated portion of the second electrode protrudes toward the other end side.

Provided are a separator for a lithium secondary battery including a substrate and a heat-resistance porous layer disposed on at least one surface of the substrate and including a cross-linked binder, wherein the cross-linked binder has a cross-linking structure of a compound represented by Chemical Formula 2, and a lithium secondary battery including the same.