Capacitor element, electrolytic capacitor, and method for manufacturing capacitor element and electrolytic capacitor

An electrolytic capacitor having reduced ESR is achieved by using a capacitor element provided with a positive electrode body having a porous region on the surface, a dielectric layer covering at least a portion of the positive electrode body, and a negative electrode layer covering at least a portion of the dielectric layer, the positive electrode body has a positive electrode part and a negative electrode forming part which is adjacent to the positive electrode part and on which the negative electrode layer is formed, and a thin-walled region which is thinner than the porous region in the negative electrode forming part is formed in at least a part of the porous region of the positive electrode part. A metal base material is laminated on at least a part of the thin region, and the metal base material is denser than the porous region in the cathode forming part. 通过使用如下电容器元件来实现ESR得以降低的电解电容器，所述电容器元件具备：在表面具有多孔区域的阳极体、覆盖所述阳极体的至少一部分的电介质层、和覆盖所述电介质层的至少一部分的阴极层，所述阳极体具有：阳极部、和与所述阳极部邻接并且形成有所述阴极层的阴极形成部，在所述阳极部的所述多孔区域的至少一部分