Solar Battery Module Bus Bar Electrode Design

Solution Overview

Problem

The formation of narrow bus bar electrodes in solar cell modules leads to increased pressing force and non-uniform pressure application during connection, risking fracture or crack generation, particularly in thinner substrates, which reduces manufacturing yield.

Innovation Solution

The design features bus bar electrodes with a wider region width than the connection member, allowing for reliable placement even with mechanical errors, and uses a resin adhesive for mechanical and electrical connection, distributing pressure and enhancing connection strength.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of substance

If a bus bar electrode is formed to have a narrow width to reduce material cost, then the amount of electrode materials is reduced, but the pressing force applied on the solar cell becomes larger and non-uniform, causing fracture or crack

Engineering Contradiction:

Improveamount of electrode materialsVSAvoidstructural integrity of solar cell

Core Design Contradiction:

Loss of substanceVSStrength

Solution Approach 1:

The bus bar electrode is designed with non-uniform width: a first width in the pressing direction and a second width perpendicular to the pressing direction. This local variation in dimensions allows the electrode to distribute pressing force more evenly across the solar cell surface while maintaining reduced overall material usage. The wider dimension perpendicular to pressing provides structural support and force distribution, while the narrower dimension in the pressing direction reduces material consumption.

Inventive Principle:

Principle #3Local quality

2Loss of substance

If a bus bar electrode is formed to have a narrow width to reduce material cost, then the amount of electrode materials is reduced, but manufacturing yield is reduced due to fracture or crack

Engineering Contradiction:

Improveamount of electrode materialsVSAvoidmanufacturing yield

Core Design Contradiction:

Loss of substanceVSProductivity

Solution Approach 1:

The bus bar electrode is designed with non-uniform width: a first width in the pressing direction and a second width perpendicular to the pressing direction. This local variation in dimensions allows the electrode to distribute pressing force more evenly across the solar cell surface while maintaining reduced overall material usage. The wider dimension perpendicular to pressing provides structural support and force distribution, while the narrower dimension in the pressing direction reduces material consumption.

Inventive Principle:

Principle #3Local quality

3Loss of substance

If a bus bar electrode is formed to have a narrow width to reduce material cost, then the amount of electrode materials is reduced, but the pressing pressure is not applied vertically and uniformly, causing connection defects

Engineering Contradiction:

Improveamount of electrode materialsVSAvoiduniformity of pressing pressure

Core Design Contradiction:

Loss of substanceVSManufacturing precision

Solution Approach 1:

The bus bar electrode is designed with non-uniform width: a first width in the pressing direction and a second width perpendicular to the pressing direction. This local variation in dimensions allows the electrode to distribute pressing force more evenly across the solar cell surface while maintaining reduced overall material usage. The wider dimension perpendicular to pressing provides structural support and force distribution, while the narrower dimension in the pressing direction reduces material consumption.

Inventive Principle:

Principle #3Local quality

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 configuration prevents fractures and cracks, improves manufacturing yield, and reduces material costs by allowing for thinner substrates and more efficient electrode material usage.

Implementation Method 1

connection between the conductive connection member and a front electrode or a rear electrode is achieved by a resin adhesive containing a resin

Methodology Applied

Scientific EffectAdhesive bonding: Adhesive

Data Source

PatentEP2469604B1Solar battery module

Publication Date: 2019.10.09 PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO LTD

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AI summary

Disclosed are a solar battery and a solar battery module with which the amount of electrode material used is small and the manufacturing yield is good. The solar battery is provided with a first main surface side electrode (40) and a second main surface side electrode (41). The first main face side electrode (40) has a plurality of fine wire-shaped electrodes (40a) and connection electrodes (40b) which are electrically connected to the plurality of fine wire-shaped electrodes (40a). The width of the connection electrodes (40b) of the first main face side electrode (40) is smaller than the width of the connection member used for solar battery connection. The second main face side electrode (41) has a plurality of fine wire-shaped electrodes (41a) and connection electrodes (41b) which are electrically connected to the plurality of fine wire-shaped electrodes (41a). The width of the connection electrodes (41b) of the second main face side electrode (41) is larger than the region width (W) of the connection electrodes (40b) of the first main face side electrode (40).