Abstract: A secondary battery includes an electrode assembly having a positive electrode provided with a positive electrode tab, a separator, and a negative electrode provided with a negative electrode tab, the positive electrode, the separator, and the negative electrode being wound, the electrode assembly having a core part at a center thereof; a can configured to receive the electrode assembly therein, the negative electrode tab being connected to the can; a cap assembly coupled to an opening of the can, the positive electrode tab being connected to the cap assembly; and a reinforcing member provided on an end of the separator exposed beyond the positive electrode or the negative electrode to prevent heat of the positive electrode tab or the negative electrode tab from being transferred to the separator.

Abstract: Disclosed is an apparatus for recovering an acrylic acid from a mixture containing acrylic acid, acrylic acid dimer and impurities with high boiling point, including: an acrylic acid recovering device that comprises an acrylic acid distillation unit being present within an acrylic acid dimer pyrolysis tank, and is operated under reduced pressure; a separation column for removing impurities with high boiling point from the mixture which is introduced into the acrylic acid recovering device; and a line for introducing the mixture into the acrylic acid recovering device.

Abstract: Disclosed is a simplified apparatus for recovering acrylic acid from a mixture containing acrylic acid, acrylic acid dimer and impurities with high boiling point, in a stable and efficient manner. An apparatus for recovering an acrylic acid from a mixture containing acrylic acid, acrylic acid dimer and impurities with high boiling point, which comprises: an acrylic acid recovering device that comprises an acrylic acid distillation unit being present within an acrylic acid dimer pyrolysis tank, and is operated under reduced pressure; and a line for introducing the mixture into the acrylic acid recovering device, wherein decomposition of the acrylic acid dimer is carried out under reduced pressure at a lower part of the acrylic acid recovering device, while the acrylic acid is recovered by distillation under reduced pressure from a top of the acrylic acid recovering device.