Thin-Film Solar Module One-Sided Contact Layer Design
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing thin-film solar modules face challenges in achieving efficient series connection and reduced structuring effort due to alignment issues and high structuring complexity, especially with small point contacts on large areas, which limits their efficiency and production feasibility.
Innovation Solution
A thin-film solar module design featuring a one-sided contact system with a flat second contact layer and an inner contact layer, where the first contact system's contacts protrude through the inner layer, eliminating the need for additional structuring and alignment of point contacts, and using linear or meandering insulating trenches for series connections.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Area of moving object
If small point contacts are used on large areas for series connection, then contact area is minimized, but alignment precision and structuring complexity increase significantly
Solution Approach 1:
The contact system is segmented into two distinct layers: a first contact layer with point contacts for one polarity and a second contact layer with point contacts for the opposite polarity. This segmentation allows each layer to be optimized independently, with the first layer providing mechanical support and the second layer providing precise electrical contact, thereby reducing alignment complexity while maintaining minimal contact area.
Solution Approach 2:
The invention transitions from a single-layer contact system to a two-layer contact system, adding a vertical dimension to the contact architecture. The point contacts of the first layer are positioned at different vertical levels than the point contacts of the second layer, allowing series connection without requiring precise lateral alignment between contacts of opposite polarity.
2Productivity
If complex structuring is used to achieve series connection, then connection efficiency is improved, but manufacturing complexity and cost increase
Solution Approach 1:
The series connection structure is segmented into alternating regions of first contact layer and second contact layer along the linear connection path. This segmentation creates a simplified repeating pattern that can be manufactured using standard photolithography processes, reducing structuring complexity while maintaining efficient series connection across multiple solar cells.
3Area of stationary object
If point contacts are used to minimize dead zones, then active area is maximized, but alignment and manufacturing difficulty increase
Solution Approach 1:
By utilizing the vertical dimension with two stacked contact layers, the invention achieves minimal dead zones through point contacts while simplifying manufacturing. The point contacts in the first layer and second layer are offset vertically, allowing each layer to be patterned and aligned independently during manufacturing, thereby reducing the overall manufacturing difficulty despite the minimal contact area requirement.
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 design significantly reduces structuring effort, eliminates alignment problems, and minimizes dead zones, enhancing efficiency by allowing for simpler and more cost-effective production of thin-film solar modules with improved light absorption and reduced shadowing losses.
Implementation Method 1
The solar cell areas of the thin-film solar modules convert light into electrical energy
Implementation Method 2
layers or areas of different conductivity for positive (p, holes, p-type) and negative (n, electrons, n-type) charge carriers due to doping
Data Source
Figure 1A~1B
Figure 2~3
Figure 4~5
AI summary
The closest known thin-film solar module which is contact-connected on the rear side is based on two contact systems with different point contact-connections, the structuring of which, however, limits the quality of the absorber material used, with the result that pin configurations, in particular, can be achieved only with difficulty. For connection in series, the point contact-connections of the first and second contact systems must be exactly aligned with one another. In contrast, the thin-film solar cell module (00) according to the invention has a second contact system (13) having only one flat internal contact layer (16). The first contact system (12) has contact-connections (14) which are detected by an outer contact layer (15). For connection in series, the contact-connections (14) are connected to the internal contact area (16) in connection regions (21) between adjacent solar cell regions (09, 10) using series contact-connections (22). Outside the connection regions (22), the two contact systems (12, 13) are electrically insulated with respect to one another by the interposition of an insulation layer (17). The thin-film solar module (00) according to the invention can be implemented in a simple manner in all possible embodiments (pn or pin configuration, contact-connection on the rear side or front side, superstrate or substrate, integration of additional functional layers) without any alignment problems and yields the greatest possible degree of efficiency.