Back Contact Solar Cell Module Interconnector Protection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing solar cell modules face challenges in protecting back contact solar cells from moisture and corrosion while maintaining efficient electrical connections and aesthetics, particularly due to the visibility of metal interconnectors through the light-receiving surface.
Innovation Solution
A solar cell module design incorporating a cured liquid filler as a protective layer, formed from poly dialkyl siloxane, which covers the interconnector and provides a uniform appearance, combined with upper and lower protective layers of different materials, including ethylene vinyl acetate and tempered glass, to prevent moisture and corrosion, and automate manufacturing processes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If metal interconnectors are used to electrically connect back contact solar cells, then electrical connection efficiency is improved, but the metal color becomes visible through the light receiving surface, degrading aesthetics
Solution Approach 1:
A color matching layer is introduced as an intermediary between the metal interconnector and the light receiving surface. This layer has the same color as the semiconductor substrate and prevents the metal color from being observed through the light receiving surface, while still allowing electrical connection to function
Solution Approach 2:
The color of the interconnector region is modified by applying a color matching layer that matches the semiconductor substrate color. This changes the visual appearance from metallic to substrate-matching color, eliminating the aesthetic degradation while preserving electrical functionality
2Reliability
If protective layers are applied to protect back contact solar cells from moisture and corrosion, then reliability is improved, but the complexity of the manufacturing process increases
Solution Approach 1:
Multiple protective functions are merged into a single integrated structure. The encapsulant material provides both moisture barrier and mechanical protection functions, while the color matching layer simultaneously provides aesthetic protection and electrical insulation. This reduces the number of separate manufacturing steps compared to applying multiple distinct protective layers
Solution Approach 2:
The encapsulant material serves multiple functions: it acts as a moisture barrier, provides mechanical protection, enables thermal bonding during curing, and maintains structural integrity. This multi-functionality reduces the need for additional specialized protective components and simplifies the overall manufacturing process
3Shape
If liquid filler is used to cover interconnectors, then appearance uniformity is improved, but the curing process requires additional thermal processing steps
Solution Approach 1:
The curing process of the liquid filler is merged with the existing thermal processing steps in the solar cell manufacturing sequence. The encapsulant curing and filler curing are performed in an integrated thermal cycle, eliminating the need for separate curing steps and minimizing additional manufacturing cycle time
Solution Approach 2:
The liquid filler undergoes a phase transition from liquid to solid through thermal curing. This phase change allows the filler to initially flow and conform to the interconnector shape for uniform appearance, then solidifies to provide structural stability. The phase transition is achieved through controlled thermal processing that integrates with existing manufacturing cycles
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 solution effectively protects back contact solar cells from environmental factors, enhances electrical insulation, and improves the appearance by matching the interconnector color to the solar cell substrate, thereby increasing module efficiency and reliability.
Implementation Method 1
a portion of the applied siloxane precursor is filled in a space between the back contact solar cells because of the fluidity properties of the siloxane precursor and is cured through a thermal process
Data Source
AI summary
A solar cell module and a method of manufacturing the same are discussed. The solar cell module includes a plurality of back contact solar cells, an interconnector that is positioned on back surfaces of the plurality of back contact solar cells and electrically connects adjacent back contact solar cells to one another, upper and lower protective layers for protecting the plurality of back contact solar cells, a transparent member that is positioned on the upper protective layer on light receiving surfaces of the plurality of back contact solar cells, and a back sheet that is positioned under the lower protective layer on surfaces opposite the light receiving surfaces of the plurality of back contact solar cells. The upper protective layer and the lower protective layer are formed of different materials.