Integrated Polyphase Hydrogel Electrodes for Stretchable Supercapacitors
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing stretchable supercapacitors face challenges in optimizing the interface connection between electrodes and electrolytes, leading to unsatisfactory capacitance retention during stretching deformation due to poor interfacial bonding, limited electrode thickness, and mismatched mechanical properties, which hinder the development of devices with high energy and power density.
Innovation Solution
A preparation method for an integrated polyphase hydrogel is developed, comprising the formation of PVA/SA/PA semigel electrolyte and PVA/PA/PANI/HPA semigel electrodes, which are injected into each other to create parallel electrodes within a mold, forming a structure that enhances interfacial toughness and mechanical properties, allowing for high strain tolerance and easy integration.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If traditional sandwich structure with external metal interconnections is used, then high voltage output is achieved, but device complexity and manufacturing difficulty increase significantly
Solution Approach 1:
The patent merges the electrode and current collector into a single integrated component. The conductive polymer electrode (PANI) directly serves as both the electrochemically active material and the current collection pathway, eliminating the need for separate metal current collectors and interconnection wires. This integration simplifies the device structure while maintaining high voltage output capability through series connection of multiple electrode pairs within the hydrogel matrix.
2Device complexity
If 2D planar structure with polymer substrate is used, then external metal interconnection is eliminated, but interfacial bonding between electrode and substrate is poor leading to unsatisfactory capacitance retention during stretching
Solution Approach 1:
The patent employs a composite hydrogel system where the electrolyte hydrogel (PVA/SA/PA) and electrode hydrogel (PVA/PA/PANI/HPA) are chemically and physically integrated. The hydrogel matrix provides continuous mechanical support and electrical connectivity throughout the bulk phase, eliminating the electrode-substrate interface problem. The crosslinked hydrogel network ensures strong interfacial bonding while maintaining stretchability, achieving both simplicity and reliability.
Solution Approach 2:
The patent changes the mechanical properties of the electrode material by incorporating it into a hydrogel matrix with tailored crosslinking density and composition. The PVA/PA/PANI/HPA composite hydrogel exhibits enhanced mechanical toughness and elasticity compared to rigid planar electrodes, enabling the electrode to withstand stretching deformation without delamination or fracture, thus maintaining capacitance retention.
3Reliability
If interface engineering method is applied to eliminate stretching strain at interface, then interfacial bonding is improved, but electrode coating thickness is limited due to unsuitability for bulk phase of thicker electrodes
Solution Approach 1:
The patent merges the electrode and electrolyte into a single bulk hydrogel phase, eliminating the distinct interface that limits electrode thickness in traditional sandwich structures. The conductive polymer electrode is distributed throughout the bulk of the electrolyte hydrogel, allowing thick electrodes to be formed without interfacial delamination issues. The entire bulk phase acts as both electrolyte and electrode support matrix.
4Use of energy by moving object
If thicker electrode coatings are used to increase energy density, then energy density is improved, but interfacial bonding fails due to mismatched mechanical properties between thick electrode and substrate
Solution Approach 1:
The patent creates a composite hydrogel where the electrode material (PANI) is integrated within the electrolyte hydrogel matrix (PVA/SA/PA). This composite structure allows the electrode to have sufficient thickness for high energy density while the hydrogel matrix provides continuous mechanical support and stress distribution throughout the bulk phase, preventing interfacial failure even under large strain conditions.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The integrated polyphase hydrogel maintains superior interfacial toughness and capacitance retention under mechanical deformation, achieving high energy and power density with excellent charge and discharge cycle stability, and simplifies the integration process by eliminating the need for external metal interconnections.
Implementation Method 1
dissolving the polyvinyl alcohol in the phytic acid, stirring at 75-95° C. for 2-3 h, then adding ammonium persulfate and heteropoly acid to obtain a homogeneous solution, adding phytic acid and aniline to the solution, stirring continuously at 75-95° C. for 3-4 h
Implementation Method 2
PVA/PA/PANI/HPA semigel electrode
Implementation Method 3
dissolving polyvinyl alcohol and phytic acid in water, then adding sulfuric acid, stirring at 75-95° C. for 2-3 h to obtain a homogeneous solution
Implementation Method 4
finally freezing the mold and then thawing at room temperature to obtain an integrated polyphase hydrogel
Data Source
AI summary
The present invention discloses an integrated multiphase hydrogel, and a preparation method and application thereof in flexible and stretchable supercapacitors. The integrated multiphase hydrogel of the present invention is formed by implanting semigel electrode into semigel electrolyte by injection or printing, wherein the electrolyte hydrogel is prepared by polyvinyl alcohol, phytic acid and sulfuric acid. The electrode hydrogel is prepared from heteropoly acid, polyvinyl alcohol, phytic acid, ammonium persulfate and aniline by heating and then freeze thawing. The hydrogel of the present invention can be directly used as anode and cathode of stretchable electrode of flexible and stretchable supercapacitor without any post-processing. The electrolyte hydrogel can be used as both stretchable electrolyte and elastic substrate. The prepared flexible and stretchable supercapacitor can maintain superior interfacial toughness, have excellent charging/discharging cycle stability, and have good capacitance retention under mechanical deformation conditions such as bending, twisting and stretching.