High Strain Point Glass Composition for Photovoltaic Modules
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current glass compositions that achieve high strain points and matching thermal expansion coefficients with lower cost glass components are costly and do not adequately match the thermal expansion values of soda-lime glass, leading to potential delamination and structural integrity issues in applications like photovoltaic modules and magnetic recording articles.
Innovation Solution
A glass composition comprising 57-75% SiO2, 3-11% Al2O3, 6-11% Na2O, 16-21% CaO, 0.01-0.1% Li2O, and less than 0.05% K2O, which achieves a strain point of at least 590°C and a coefficient of thermal expansion of at least 7.4 ppm/°C, enabling compatibility with lower cost glass components.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If glass compositions with rare earth oxides or boron are used to increase strain point, then strain point increases, but cost increases and coefficient of thermal expansion values become less matched to lower cost glass components
Solution Approach 1:
The patent changes the chemical composition parameters by using specific ranges of SiO2 (57-75%), Al2O3 (3-11%), Na2O (6-11%), and CaO (16-21%) to achieve the desired strain point of at least 590°C while controlling the coefficient of thermal expansion to be within 0.5 ppm/°C of soda-lime glass, thus resolving the contradiction between achieving high strain point and maintaining cost-effectiveness with matched thermal expansion properties
Solution Approach 2:
The patent creates a composite glass composition by combining multiple oxides (SiO2, Al2O3, Na2O, CaO, Li2O, K2O) in specific proportions to simultaneously achieve high strain point (≥590°C) and coefficient of thermal expansion matching with soda-lime glass, avoiding the need for expensive rare earth oxides or boron while maintaining both required properties
2Temperature
If glass compositions with rare earth oxides or boron are used to increase strain point, then strain point increases, but coefficient of thermal expansion values become less matched to lower cost glass components
Solution Approach 1:
The patent adjusts the chemical composition parameters to achieve a strain point of at least 590°C while simultaneously controlling the coefficient of thermal expansion to be within 0.5 ppm/°C of soda-lime glass, thus resolving the contradiction between achieving high strain point and maintaining matched thermal expansion properties
Solution Approach 2:
The patent develops a composite glass composition using SiO2, Al2O3, Na2O, CaO, Li2O, and K2O in optimized proportions that simultaneously delivers high strain point (≥590°C) and coefficient of thermal expansion matching with soda-lime glass, eliminating the need for expensive rare earth oxides or boron while maintaining both required properties
Data Source
AI summary
The present invention relates to a glass composition that includes: 57 to 75 percent by weight of SiO2; 3 to 11 percent by weight of Al2O3; 6 to 11 percent by weight of Na2O; 16 to 21 percent by weight of CaO; 0.01 to 0.1 percent by weight of Li2O; and less than 0.05 percent by weight of K2O. Each percent by weight is based on total weight of the glass composition. Glass products are also provided that have a bulk glass composition as described above. The glass products, such as flat glass products and glass substrates, have a strain point of at least 590° C. and a thermal expansion of at least 7.4 ppm/° C. The present invention also relates to magnetic recording articles and photovoltaic cells that include a glass substrate that has a bulk glass composition as described above.