Core, high-voltage multilayer solid aluminum electrolytic capacitor and method for preparing same

A method for preparing a multilayer solid aluminum electrolytic capacitor, comprising:

• (S1) processing each of a first rectangular insulating plate and a second rectangular insulating plate by punching to form a rectangular hollow portion with a preset size thereon;
• (S2) coating a first insulating adhesive on one side of each of the first rectangular insulating plate and the second rectangular insulating plate obtained in step (S1);
• and bonding the first rectangular insulating plate coated with the first insulating adhesive to an upper side of a rectangular aluminum foil, and bonding the second rectangular insulating plate coated with the first insulating adhesive to a lower side of the rectangular aluminum foil to obtain a first composite;
• (S3) successively forming, from inside to outside, a conductive polymer layer, a conductive carbon paste layer and a conductive silver paste layer on the hollow portion on each of two sides of the first composite to obtain a second composite;
• (S4) coating a second insulating adhesive on a side surface, an upper surface and a lower surface of an end of the second composite to form a U-shaped insulating adhesive layer, so as to obtain a core;
• (S5) sequentially stacking N cores from bottom to top, wherein each of the N cores is the core obtained in step (S4);
• and connecting and fixing the N cores with a conductive frame layer by layer to obtain a first core package;
• wherein an end of each of the N cores provided with the U-shaped insulating adhesive layer faces towards the conductive frame;
• (S6) punching an end of the first core package that is not connected to the conductive frame to form a through hole;
• inserting a strip rivet into the through hole;
• bending two ends of the strip rivet exposed outside the through hole in a direction away from the conductive frame to abut a surface of the first core package to form a pair of bent portions, such that a second core package is obtained;
• (S7) bonding a lower one of the pair of bent portions to an anode horizontal portion of a substrate through a conductive silver adhesive;
• and bonding the conductive silver paste layer on a lower surface of a lowermost one among the N cores, a first conductive portion of the conductive frame and a cathode horizontal portion of the substrate through the conductive silver adhesive to form a third core package;
• and
• (S8) encapsulating the third core package with an epoxy resin moulding material, such that an upper surface and four side surfaces of the substrate, the N cores, the conductive frame and the strip rivet are wrapped by a resin casing, and a lower surface of the substrate, a lower surface of an anode terminal and a lower surface of a cathode terminal are exposed outside the resin casing to obtain the multilayer solid aluminum electrolytic capacitor.