Solar Cell Electrode Composition Reducing Resistance

Solution Overview

Problem

Existing electrode compositions for solar cells face challenges in achieving high conversion efficiency due to increased contact resistance and series resistance, particularly when scaling solar cell area, and struggle with maintaining fine line widths and printing stability during the firing process.

Innovation Solution

A composition for forming electrodes comprising a solvent, conductive powder, glass frit, and an organic binder with specific structural units, which improves dispersibility, storage stability, and adhesion, while minimizing contact resistance and series resistance, and allows for the formation of fine line patterns.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If conventional electrode compositions are used, then manufacturing process is simple, but contact resistance and series resistance increase reducing conversion efficiency

Engineering Contradiction:

Core Design Contradiction:

ReliabilityVSObject-generated harmful factors

Solution Approach 1:

The patent modifies the chemical composition parameters of the electrode paste by incorporating specific organic binders with controlled molecular weight (1,000-300,000 g/mol) and specific functional groups, along with optimized ratios of conductive powder (60-95 wt%), glass frit (0.5-20 wt%), and organic binder (0.1-20 wt%). These parameter changes reduce contact resistance and series resistance while improving conversion efficiency.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent creates a composite electrode material combining conductive powder, glass frit, and specially formulated organic binder in specific proportions. This composite structure optimizes both electrical conductivity and adhesion properties, reducing harmful resistance while maintaining manufacturing simplicity.

Inventive Principle:

Principle #40Composite materials

2Strength

If firing temperature is increased to improve adhesion, then electrode bonding strength increases, but line width control deteriorates and printing stability decreases

Engineering Contradiction:

Core Design Contradiction:

StrengthVSManufacturing precision

Solution Approach 1:

The patent changes the chemical composition parameters of the organic binder to include specific functional groups and molecular weight ranges that enable strong adhesion at lower firing temperatures. This allows maintaining line width precision while achieving sufficient bonding strength through optimized paste formulation rather than temperature increase.

Inventive Principle:

Principle #35Parameter changes

3Productivity

If solar cell area is increased to improve power output, then energy generation capacity increases, but contact resistance and series resistance increase reducing efficiency

Engineering Contradiction:

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The patent optimizes the electrical conductivity parameters of the electrode composition by adjusting conductive powder content (60-95 wt%) and binder composition, enabling larger solar cells to maintain low series resistance and high conversion efficiency despite increased area and current collection demands.

Inventive Principle:

Principle #35Parameter changes

Data Source

PatentUS10898952B2Composition for forming electrode, electrode manufactured using the same and solar cell

Publication Date: 2021.01.26

AI summary

A composition for forming an electrode includes a conductive powder, a glass frit, an organic binder, and a solvent. The organic binder includes a polymer including a structural unit represented by Chemical Formula 1 and a structural unit represented by Chemical Formula 2.In Chemical Formulae 1 and 2, each substituent of Chemical Formulae 1 and 2 is the same as in the detailed description.