In-Line Wafer Solar Cell Contacting With Pressure-Controlled Conveyance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing systems for electrically contacting wafer solar cells are inefficient in optimizing contact quality and characterizing solar cells, particularly in ensuring reliable and damage-free mechanical and electrical contact during the production process.
Innovation Solution
The system employs upper and lower contact devices designed to convey wafer solar cells along an in-line transportation direction, using adjustable electrical voltage to optimize front- and rear-face electrode contacts, combined with a laser device to enhance electrical contact quality, and includes a conveyor belt or chuck mechanism to manage contact pressure and prevent mechanical damage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a single roller or brush is guided along a stationary wafer solar cell to apply voltage, then the electrical contacting of the front-face electrode is improved, but the system cannot efficiently convey multiple wafers in an in-line production process
Solution Approach 1:
Instead of guiding a roller or brush along a stationary wafer solar cell, the patent inverts the approach by making the contact devices move with the wafer solar cell during in-line conveyance. The upper and lower contact devices are designed to convey the wafer solar cell along the in-line transportation direction, maintaining continuous electrical contact while enabling efficient production flow.
Solution Approach 2:
The contact devices are designed to perform multiple functions simultaneously: they electrically contact the front-face and rear-face electrodes of the wafer solar cell while also mechanically conveying it through the production line. This multi-functionality resolves the contradiction between ensuring reliable electrical contact and maintaining high production efficiency.
2Reliability
If contact pressure is increased to improve electrical contact quality, then contact reliability improves, but mechanical damage to the wafer solar cell increases
Solution Approach 1:
The patent employs dynamic contact pressure control where the contact devices adjust their pressure based on the wafer solar cell's position and properties. The system applies sufficient pressure to ensure reliable electrical contact between the contact devices and the front-face/rear-face electrodes, while preventing excessive pressure that could cause mechanical damage. This dynamic adjustment resolves the contradiction between contact reliability and damage prevention.
3Productivity
If the wafer solar cell is conveyed during contacting operation, then in-line production efficiency is improved, but maintaining consistent contact pressure becomes more difficult
Solution Approach 1:
The system incorporates feedback mechanisms that continuously monitor the contacting process during in-line conveyance. Sensors detect parameters such as contact force, electrical resistance, and wafer position, and this information is fed back to control systems that adjust contact device positioning and pressure in real-time. This feedback control ensures consistent contact pressure is maintained even while the wafer solar cell is moving through the production line, resolving the contradiction between productivity and manufacturing precision.
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 approach enables improved electrical contact quality and characterization of wafer solar cells by ensuring consistent and efficient contact formation without mechanical damage, optimizing the production process through adjustable voltage and precise contact management.
Implementation Method 1
an electrical voltage source in order to apply a defined voltage to the wafer solar cell and to regulate the flow of current between the upper contact device and the lower contact device
Implementation Method 2
a spot-type light source is guided over the front face of the wafer solar cell when the voltage is applied, as a result of which a light-induced flow of current is generated
Data Source
AI summary
A system for electrically contacting wafer solar cells with a front-face electrode, including: an upper contact device for electrically contacting the front-face electrode of the wafer solar cell, —a lower contact device for electrically contacting the rear-face electrode of the wafer solar cell, and an electric voltage source for applying a defined voltage to the wafer solar cell and regulating the flow of current between the upper and lower contact devices. The upper contact device and the lower contact device are designed to additionally mechanically convey the wafer solar cell along an in-line transport direction for an in-line production line for wafer solar cells while contacting the wafer solar cell.