Solar Cell Electrode Composition Using Composite Glass Frit
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing solar cell electrode compositions face challenges in achieving both good adhesion to a substrate and low contact resistance, as lead-containing glass frits provide easy adhesion but high contact resistance, while tellurium-containing glass frits improve contact resistance but compromise adhesion.
Innovation Solution
A composition for solar cell electrodes using a first glass frit with a tellurium and silver molar ratio of 75:1 to 1:25, combined with a lead-tellurium-oxide or bismuth-tellurium-oxide based glass frit without silver, to enhance adhesion and resistance characteristics, along with silver powder and an organic vehicle, optimizing the weight ratios and additives for improved performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If lead-containing glass frit is used, then adhesion to substrate is improved, but contact resistance increases
Solution Approach 1:
The patent uses a composite glass frit system combining lead-containing glass frit (for adhesion) with tellurium-containing glass frit (for low contact resistance). This composite approach allows both functions to coexist: the lead component provides strong bonding to the substrate while the tellurium component maintains low electrical resistance at the contact interface.
Solution Approach 2:
The invention applies different glass frit compositions to different functional requirements within the same electrode structure. The lead-containing portion addresses adhesion needs at the substrate interface, while the tellurium-containing portion addresses electrical conductivity needs at the contact interface, creating localized functional optimization.
2Object-affected harmful factors
If tellurium-containing glass frit is used, then contact resistance is reduced, but adhesion to substrate deteriorates
Solution Approach 1:
The patent combines tellurium-containing glass frit (which provides low contact resistance) with lead-containing glass frit (which provides strong adhesion). This composite formulation ensures that the benefits of tellurium (low resistance) are realized without suffering from its drawback (poor adhesion), as the lead component compensates for the adhesion deficiency.
Solution Approach 2:
The invention creates localized functional zones within the glass frit layer where tellurium-rich regions provide low electrical resistance while lead-rich regions provide strong substrate bonding, allowing each component to optimize its specific function without compromising the other.
3Object-affected harmful factors
If silver powder content is increased, then electrical conductivity is improved, but manufacturing cost increases
Solution Approach 1:
The patent optimizes the silver powder content within a specific range (60-95 wt%) rather than using maximum possible silver. This parameter optimization achieves the necessary electrical conductivity (low series resistance) while controlling material costs. The glass frit composition also plays a role in enhancing conductivity, allowing slightly lower silver content while maintaining performance.
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 composition achieves low series resistance and high conversion efficiency, with excellent adhesion to the substrate and improved fill factor, addressing the trade-off between adhesion and resistance.
Implementation Method 1
The glass frit includes a first glass frit and a second glass frit. The first glass frit includes tellurium (Te) and silver (Ag) in a molar ratio (Te:Ag) of about 75:1 to about 1:25
Implementation Method 2
Solar cells generate electricity using the photovoltaic effect of a p-n junction which converts photons of sunlight into electricity
Data Source
AI summary
A composition for solar cell electrodes includes silver powder, a glass frit, and an organic vehicle. The glass frit includes a first glass frit and a second glass frit. The first glass frit includes tellurium (Te) and silver (Ag) in a molar ratio (Te:Ag) of about 75:1 to about 1:25. The second glass frit includes a lead-tellurium-oxide (Pb—Te—O)-based glass frit or a bismuth-tellurium-oxide (Bi—Te—O)-based glass frit and is free from silver (Ag).