Solid aluminum electrolytic capacitor with good mechanical stability and preparation method thereof
By doping Pt nanoparticles with Cu(BDC-NH2)MOF in PEDOT:PSS films to form a physical cross-linking network, the problem of PEDOT:PSS film peeling during charge-discharge cycles was solved, and the mechanical stability and conductivity of solid aluminum electrolytic capacitors were improved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- YIYANG ANXING ELECTRONICS
- Filing Date
- 2026-03-05
- Publication Date
- 2026-04-17
AI Technical Summary
In existing solid aluminum electrolytic capacitors, the PEDOT:PSS film continuously shrinks and expands during charge-discharge cycles, leading to film peeling, decreased capacitance, increased internal resistance, and poor mechanical stability.
In PEDOT:PSS films, nano-Pt particles are doped. The nano-Pt particles combine with Cu(BDC-NH2)MOF to form a physical cross-linking network, which enhances the mechanical stability of the film.
The mechanical stability of the PEDOT:PSS film was improved by doping with nano-Pt particles, the peeling of the film on the anode foil surface was reduced, the internal resistance was lowered and the conductivity of the capacitor was improved.
Abstract
Description
Technical Field
[0002] This invention relates to an aluminum electrolytic capacitor, and more particularly to a solid aluminum electrolytic capacitor with good mechanical stability and its preparation method. Background Technology
[0004] In solid aluminum electrolytic capacitors, conductive polymers are generally PEDOT films or PEDOT:PSS films. When using PEDOT, it is usually obtained by in-situ polymerization. However, the oxidant damages the oxide film on the surface of the anode foil. Therefore, it is now more common to use direct impregnation of PEDOT:PSS dispersion.
[0005] The PEDOT:PSS film formed by impregnation on the core is very thin. During the charge and discharge cycles of a solid aluminum electrolytic capacitor, the PEDOT:PSS film will continuously shrink and expand. As the PEDOT:PSS film on the anode foil surface continuously shrinks and expands, the PEDOT:PSS film will peel off from the anode foil surface, resulting in a decrease in capacitance and an increase in internal resistance of the solid aluminum electrolytic capacitor. Summary of the Invention
[0007] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide a solid aluminum electrolytic capacitor with good mechanical stability and its preparation method.
[0008] To solve the above technical problems, the technical solution proposed by the present invention is: a solid aluminum electrolytic capacitor with good mechanical stability, comprising a core package, characterized in that: a PEDOT:PSS film is formed inside the core package, the PEDOT:PSS film is doped by nano-Pt particles; the weight of the nano-Pt particles is less than 5% of the total weight of the PEDOT:PSS film.
[0009] Preferably, in the above-mentioned solid aluminum electrolytic capacitor with good mechanical stability, the nano-Pt particles are anchored on Cu(BDC-NH2)MOF and then doped together into the PEDOT:PSS film, and the weight ratio of the nano-Pt particles to Cu(BDC-NH2)MOF is 1:1 to 1:10.
[0010] Preferably, in the above-mentioned solid aluminum electrolytic capacitor with good mechanical stability, the core is impregnated with PEDOT:PSS dispersion multiple times to form a multilayer PEDOT:PSS film, and nano-Pt particles are doped on the first layer of PEDOT:PSS film formed by the first impregnation of PEDOT:PSS dispersion in the core.
[0011] Preferably, in the above-mentioned solid aluminum electrolytic capacitor with good mechanical stability, after a PEDOT:PSS film is formed on the core package, the core package is impregnated with electrolyte.
[0012] A method for preparing a solid aluminum electrolytic capacitor with good mechanical stability includes the following steps: 1) Preparation of nano-Pt particle dispersion; 2) Disperse PEDOT:PSS powder in a solvent to form a PEDOT:PSS dispersion; 3) The core package is first impregnated with the nano-Pt particle dispersion from step 1), and then dried; then impregnated with the PEDOT:PSS dispersion from step 2), and then dried, forming a PEDOT:PSS film doped with nano-Pt particles inside the core package. 4) Assemble the core package inside the outer shell to prepare a solid aluminum electrolytic capacitor.
[0013] In the preferred embodiment of the above-mentioned method for preparing a solid aluminum electrolytic capacitor with good mechanical stability, after forming a PEDOT:PSS film on the core package in step 3), the core package is impregnated with electrolyte.
[0014] In the preferred embodiment of the above-mentioned method for preparing a solid aluminum electrolytic capacitor with good mechanical stability, step 1) involves adding a Cu(BDC-NH2)MOF dispersion to the nano-Pt particle dispersion and mixing them evenly, so that the nano-Pt particles are anchored on the Cu(BDC-NH2)MOF.
[0015] The above-mentioned method for preparing a solid aluminum electrolytic capacitor with good mechanical stability, preferably, includes the following steps in the preparation method of Cu(BDC-NH2)MOF; ① Dissolve Cu(NO3)23H2O and NH2-BDC in DMF and mix thoroughly to form a mixed solution; the molar weight ratio of Cu(NO3)23H2O and NH2-BDC is 2:1; ② Transfer the mixed solution from step ① to a high-pressure reactor and react at 85-120℃ for 12-24 hours; ③ After removing the supernatant, wash the precipitate multiple times with DMF and / or ethanol; ④ The washed product is dried in a vacuum drying oven at 100℃-150℃ for 6-12 hours to obtain Cu(BDC-NH2)MOF.
[0016] In the preferred embodiment of the above-mentioned method for preparing a solid aluminum electrolytic capacitor with good mechanical stability, after step 3), the core package is impregnated with PEDOT:PSS dispersion multiple times.
[0017] Compared with the prior art, the advantages of the present invention are as follows: In the present invention, nano-Pt particles are doped into the PEDOT:PSS film, and the high specific surface area and high surface energy of the nano-Pt particles enable the PEDOT:PSS to form a physical cross-linking network, thereby enhancing the mechanical stability of the PEDOT:PSS film. Detailed Implementation
[0019] To facilitate understanding of the present invention, the present invention will be described more fully and in detail below with reference to preferred embodiments, but the scope of protection of the present invention is not limited to the following specific embodiments.
[0020] It should be noted that when a component is described as being "fixed to, attached to, connected to or connected to" another component, it can be directly fixed to, attached to, connected to or connected to the other component, or it can be indirectly fixed to, attached to, connected to or connected to the other component through other intermediate connectors.
[0021] Unless otherwise defined, all technical terms used herein have the same meaning as commonly understood by those skilled in the art. The technical terms used herein are for the purpose of describing particular embodiments only and are not intended to limit the scope of the invention. Example 1
[0022] This embodiment provides a solid aluminum electrolytic capacitor with good mechanical stability, including a core package containing a PEDOT:PSS film. The PEDOT:PSS film is doped with nano-Pt particles; the weight of the nano-Pt particles is less than 5% of the total weight of the PEDOT:PSS film. Because nano-Pt particles are prone to agglomeration, the weight of the nano-Pt particles is less than 2% of the total weight of the PEDOT:PSS film.
[0023] In this embodiment, in order to repair the oxide film on the surface of the anode foil, a PEDOT:PSS film is formed on the core package and then impregnated with electrolyte.
[0024] This embodiment also provides a method for preparing a solid aluminum electrolytic capacitor with good mechanical stability, characterized by including the following steps: 1) Preparation of nano-Pt particle dispersion; In order to prevent nano-Pt particles from agglomerating, surfactants such as sodium dodecyl sulfate and hexadecyltrimethylammonium bromide were added to the nano-Pt particle dispersion.
[0025] 2) Disperse PEDOT:PSS powder in a solvent to form a PEDOT:PSS dispersion; the weight concentration of PEDOT:PSS in the PEDOT:PSS dispersion is less than 5%.
[0026] 3) The core package is first impregnated with the nano-Pt particle dispersion from step 1), and then dried; then impregnated with the PEDOT:PSS dispersion from step 2), and then dried, forming a PEDOT:PSS film doped with nano-Pt particles inside the core package. 4) Assemble the core package inside the outer shell to prepare a solid aluminum electrolytic capacitor.
[0027] In this embodiment, to increase the amount of PEDOT:PSS film formed in the core package, the PEDOT:PSS dispersion can be impregnated multiple times. Generally, no nano-Pt particles are doped during subsequent impregnations of the PEDOT:PSS dispersion.
[0028] In this embodiment, due to the high surface energy of the nano-Pt particles, if they are directly added to the PEDOT:PSS dispersion, the nano-Pt particles may interact with the PSS on multiple PEDOT:PSS chains, leading to a certain degree of aggregation of PEDOT:PSS and thus affecting the impregnation of the PEDOT:PSS dispersion by the core. Furthermore, the nano-Pt particles interact with the PSS on the PEDOT:PSS through coordination or electrostatic attraction, and also interact with the sulfonate (-SO3⁻) on the PSS chains, causing phase separation between PEDOT and PSS. This results in poor uniformity of the PEDOT:PSS film formed after the core is impregnated with the PEDOT:PSS dispersion.
[0029] In this embodiment, the platinum nanoparticles possess a high specific surface area and rich surface chemical properties. The nanoparticles on their surface can interact with the sulfonate groups (-SO3⁻) on the PSS chains through strong coordination or electrostatic attraction. A single nanoparticle can simultaneously bind to PSS on the PEDOT:PSS chain, thereby forming a physically cross-linked network. This results in less deformation of the PEDOT:PSS film during charge-discharge cycles of the solid aluminum electrolytic capacitor, and makes the PEDOT:PSS film less prone to peeling from the anode foil surface.
[0030] In this embodiment, the electrostatic interaction between the nano-Pt particles and PSS is stronger than the interaction between PEDOT and PSS; in addition, the Pt particles can also serve as an electron channel between different PEDOT:PSS chains, so the conductivity of the PEDOT:PSS film after nano-Pt particle doping will be increased, thereby reducing the internal resistance of the solid aluminum electrolytic capacitor to a certain extent. Example 2
[0031] Since nano-Pt particles are prone to agglomeration, in this embodiment, the nano-Pt particles are first anchored on Cu(BDC-NH2)MOF and then doped together into the PEDOT:PSS film. The weight ratio of the nano-Pt particles to Cu(BDC-NH2)MOF is 1:1 to 1:10.
[0032] In this embodiment, the preparation method of Cu(BDC-NH2)MOF includes the following steps; ① Dissolve Cu(NO3)23H2O and NH2-BDC in DMF and mix thoroughly to form a mixed solution; the molar weight ratio of Cu(NO3)23H2O and NH2-BDC is 2:1; ② Transfer the mixed solution from step ① to a high-pressure reactor and react at 85℃-120℃ for 12-24 hours.
[0033] ③ After removing the supernatant, wash the precipitate multiple times with DMF and / or ethanol to remove unreacted raw material and solvent molecules.
[0034] ④ The washed product is dried in a vacuum drying oven at 100℃-150℃ for 6-12 hours to remove solvent molecules in the pores and obtain activated porous Cu(BDC-NH2)MOF.
[0035] In this embodiment, the nano-Pt particles can form a strong coordination with the -NH2 on Cu(BDC-NH2)MOF, thereby anchoring the nano-Pt particles onto Cu(BDC-NH2)MOF. After being anchored onto Cu(BDC-NH2)MOF, the nano-Pt particles are less prone to aggregation in the dispersion, and after being impregnated and adsorbed into the core, they are dispersed more uniformly.
[0036] In this embodiment, during the film formation process after impregnating the core with a PEDOT:PSS dispersion, the nano-Pt particles bound to Cu(BDC-NH2)MOF can undergo multiple interactions with PEDOT:PSS. PEDOT:PSS has a chain-like structure in the dispersion. During film formation, the long molecular chains of PEDOT:PSS can physically wrap around the Cu(BDC-NH2)MOF particles, and even penetrate into some of the macropores of Cu(BDC-NH2)MOF, encapsulating the Cu(BDC-NH2)MOF particles and the nano-Pt particles on their surface. The nano-Pt particles on Cu(BDC-NH2)MOF can interact strongly with the PSS on PEDOT:PSS through coordination or electrostatic attraction.
[0037] In this embodiment, the Cu(BDC-NH2)MOF-bonded nano-Pt particles can not only interact with PEDOT:PSS to form a physical cross-linking network, but also the composite particles formed by Cu(BDC-NH2)MOF-bonded nano-Pt particles can support the expansion and contraction of the PEDOT:PSS film during the charge and discharge cycles of the solid aluminum electrolytic capacitor, thereby further enhancing the mechanical stability of the solid aluminum electrolytic capacitor.
[0038] The other parts of this embodiment are the same as those in Embodiment 1.
[0039] Comparative Example 1 In this embodiment, the PEDOT:PSS film formed on the core package was not doped, and everything else was the same as in Example 1.
[0040] Thirty products from Examples 1, 2, and Comparative Example 1 with a capacity of 35V and 680µF were selected respectively, and their initial capacity, average internal resistance, and average capacity retention after 8000 charge-discharge cycles were tested. The results are shown in the table below.
[0041] .
Claims
1. A solid aluminum electrolytic capacitor with good mechanical stability comprising a core package, characterized by: A PEDOT:PSS film is formed within the core package, and the PEDOT:PSS film is doped with nano-Pt particles; the weight of the nano-Pt particles is less than 5% of the total weight of the PEDOT:PSS film.
2. The solid aluminum electrolytic capacitor with good mechanical stability according to claim 1, characterized in that: The nano-Pt particles are anchored on Cu(BDC-NH2)MOF and then doped together into the PEDOT:PSS film. The weight ratio of the nano-Pt particles to Cu(BDC-NH2)MOF is 1:1 to 1:
10.
3. The solid aluminum electrolytic capacitor with good mechanical stability according to claim 1 or claim 2, characterized in that: The core package contains multiple layers of PEDOT:PSS dispersion to form a multilayer PEDOT:PSS film. Nano-Pt particles are doped on the first layer of PEDOT:PSS film formed by the first impregnation of the core package with PEDOT:PSS dispersion.
4. The solid aluminum electrolytic capacitor with good mechanical stability according to claim 1 or claim 2, characterized in that: After a PEDOT:PSS film is formed on the core package, the core package is impregnated with electrolyte.
5. A method for preparing a solid aluminum electrolytic capacitor with good mechanical stability, characterized in that; Includes the following steps: 1) Preparation of nano-Pt particle dispersion; 2) Disperse PEDOT:PSS powder in a solvent to form a PEDOT:PSS dispersion; 3) The core package is first impregnated with the nano-Pt particle dispersion from step 1), and then dried; then impregnated with the PEDOT:PSS dispersion from step 2), and then dried, forming a PEDOT:PSS film doped with nano-Pt particles inside the core package. 4) Assemble the core package inside the outer shell to prepare a solid aluminum electrolytic capacitor.
6. The method for preparing a solid aluminum electrolytic capacitor with good mechanical stability according to claim 5, characterized in that: After forming a PEDOT:PSS film on the core package in step 3), the core package is impregnated with electrolyte.
7. The method for preparing a solid aluminum electrolytic capacitor with good mechanical stability according to claim 5, characterized in that: In step 1), a Cu(BDC-NH2)MOF dispersion is added to the nano-Pt particle dispersion and mixed evenly, so that the nano-Pt particles are anchored on Cu(BDC-NH2)MOF.
8. The method for preparing a solid aluminum electrolytic capacitor with good mechanical stability according to claim 7, characterized in that: The preparation method of the Cu(BDC-NH2)MOF includes the following steps; ① Dissolve Cu(NO3)23H2O and NH2-BDC in DMF and mix thoroughly to form a mixed solution; the molar weight ratio of Cu(NO3)23H2O and NH2-BDC is 2:1; ② Transfer the mixed solution from step ① to a high-pressure reactor and react at 85℃-120℃ for 12-24 hours; ③ After removing the supernatant, wash the precipitate multiple times with DMF and / or ethanol; ④ The washed product is dried in a vacuum drying oven at 100℃-150℃ for 6-12 hours to obtain Cu(BDC-NH2)MOF.
9. The method for preparing a solid aluminum electrolytic capacitor with good mechanical stability according to claim 5, characterized in that: After step 3) is completed, the core package is impregnated with PEDOT:PSS dispersion multiple times.