Abstract: Cathode electrode part 5 of flat plate-like element 1 is joined with cathode com terminal 7 with a conductive adhesive or the like. Element mounting part 6a of anode terminal 6 is provided with a pair of joint parts 6b for wrapping anode electrode part 4 from both sides. The tips of joint parts 6b and anode electrode part 4 are joined by laser welding such that the ratio (w/d) of the width (w) of each tip of joint parts 6b and the diameter (d) of the welding trace to be welded is 0.5 to 1.5, and more preferably, 0.5 to 1.25 for providing low ESR means for concentrating the quantity of heat at the time of welding on welding parts 6c without escape. Therefore, a stable welded state is obtained, so that the ESR is improved for achieving low ESR of the solid capacitor.

Abstract: Cathode electrode part 5 of flat plate-like element 1 is joined with cathode com terminal 7 with a conductive adhesive or the like. Element mounting part 6a of anode terminal 6 is provided with a pair of joint parts 6b for wrapping anode electrode part 4 from both sides. The tips of joint parts 6b and anode electrode part 4 are joined by laser welding such that the ratio (w/d) of the width (w) of each tip of joint parts 6b and the diameter (d) of the welding trace to be welded is 0.5 to 1.5, and more preferably, 0.5 to 1.25 for providing low ESR means for concentrating the quantity of heat at the time of welding on welding parts 6c without escape. Therefore, a stable welded state is obtained, so that the ESR is improved for achieving low ESR of the solid capacitor.

Abstract: A solid electrolytic capacitor of the present invention has a structure where respective anode sections of capacitor elements are joined to an anode lead frame by resistance welding via a through hole formed in the anode lead frame. Current thus collects to the through hole during the welding to break a dielectric oxide film layer to expose aluminum foil, and the molten aluminum collects into the through hole. Stable welding work is therefore allowed without splashing the aluminum, and a solid electrolytic capacitor having high welding strength, high reliability, and reduced ESR can be obtained.

Abstract: A solid electrolytic capacitor of the present invention has a structure where respective anode sections of capacitor elements are joined to an anode lead frame by resistance welding via a through hole formed in the anode lead frame. Current thus collects to the through hole during the welding to break a dielectric oxide film layer to expose aluminum foil, and the molten aluminum collects into the through hole. Stable welding work is therefore allowed without splashing the aluminum, and a solid electrolytic capacitor having high welding strength, high reliability, and reduced ESR can be obtained.