Solar Module Manufacturing Method for Residual Stress Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current solar module manufacturing methods require improvement in yield and reliability, particularly in reducing residual stress and warping of solar cells due to thermal expansion differences between cells and wiring members.
Innovation Solution
A manufacturing method involving a heat and pressure applying step followed by a cooling step under pressure, using a resin adhesive to bond solar cells and wiring members, which reduces residual stress and enhances productivity by controlling the temperature and pressure of the resin adhesive during the cooling process.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If heat and pressure are applied to bond solar cells and wiring members with resin adhesive, then bonding strength is improved, but residual stress and warping increase due to thermal expansion differences
Solution Approach 1:
The patent applies preliminary anti-action by implementing a cooling step under pressure immediately after the heating and pressure applying step. This cooling under pressure counteracts the thermal expansion effects and prevents residual stress and warping from developing, thereby resolving the contradiction between achieving strong bonding and preventing deformation.
Solution Approach 2:
The patent utilizes parameter changes by systematically controlling temperature and pressure throughout the bonding process. The temperature is increased during heating to achieve proper adhesive bonding, then decreased during cooling to prevent warping. Similarly, pressure is maintained throughout both heating and cooling phases to ensure strong bonding while preventing deformation, thus resolving the contradiction through dynamic parameter management.
2Reliability
If cooling is performed after heat and pressure applying, then residual stress is reduced, but production efficiency decreases due to sequential processing
Solution Approach 1:
The patent implements continuity of useful action by performing the cooling step immediately and continuously after the heating and pressure applying step, without interrupting the process. This continuous operation ensures residual stress is effectively reduced while maintaining high production efficiency, as the cooling action follows directly from the heating action without idle time or separate processing stages.
Solution Approach 2:
The patent merges the heating and cooling operations into a single integrated bonding process. By combining these two essential steps into one continuous operation where cooling immediately follows heating under the same pressure application, the patent achieves both residual stress reduction and maintained production efficiency, resolving the contradiction between reliability improvement and productivity preservation.
3Shape
If pressure is applied during cooling, then warping is minimized, but device complexity increases
Solution Approach 1:
The patent applies universality by using the same pressure applying mechanism for both the heating phase and the cooling phase. The pressure applying device serves multiple functions: it provides pressure during heating to ensure bonding, maintains pressure during cooling to prevent warping, and eliminates the need for separate pressure control systems, thus achieving warping control without significantly increasing device complexity.
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
This method improves the yield and reliability of solar modules by minimizing warping and stress, while also increasing production efficiency by allowing simultaneous heat and pressure application on one solar cell and cooling on another, thus enhancing overall manufacturing efficiency.
Implementation Method 1
solar cells and a wiring member are bonded during the manufacture of a solar module by interposing a resin adhesive between the solar cells and the wiring member and applying heat and pressure
Implementation Method 2
In the heat and pressure applying step, heat and pressure are applied to a solar cell and a wiring member opposing each other with a resin adhesive interposed between them
Implementation Method 3
In the cooling step, the solar cell and the wiring member are cooled under pressure after the heating and pressure applying step has been completed
Data Source
AI summary
Provided is a method for manufacturing solar modules with an improved yield. A heat and pressure applying step is performed in which an opposing solar cell (10) and wiring member (11) with a resin adhesive (21) interposed between them are heated while applying pressure. After the heat and pressure applying step has been performed, a cooling step is performed in which the solar cell (10) and the wiring member (11) are cooled while applying pressure.