Solar Cell Cooling Layer for LeTID Temperature Mitigation

Solution Overview

Problem

Solar cells face degradation due to Light and Elevated Temperature Induced Degradation (LeTID), which occurs when exposed to simultaneous light and heat, leading to reduced efficiency and shorter lifespan, necessitating a technology to mitigate substrate temperature increases.

Innovation Solution

Incorporating a cooling layer made of PDMS with a thickness between 5 μm to 150 μm that absorbs far-infrared rays during sunlight irradiation and emits wavelengths between 8 μm to 13 μm, utilizing natural radiation cooling to reduce LeTID phenomena.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a cooling layer is added to reduce substrate temperature and mitigate LeTID, then long-term stability and output are improved, but device complexity and manufacturing steps increase

Engineering Contradiction:

Improvelong-term stabilityVSAvoidstructure complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The cooling layer is constructed using a composite material system comprising PDMS as the base polymer and infrared-absorbing particles (such as carbon black, graphite, or metal oxides) dispersed within it. This composite structure enables the layer to absorb far-infrared radiation and convert it to heat, which is then dissipated to reduce the substrate temperature and mitigate LeTID effects.

Inventive Principle:

Principle #40Composite materials

Solution Approach 2:

The thickness of the cooling layer is optimized within a specific range (5-150 μm) to balance its cooling effectiveness with light transmission properties. By controlling this parameter, the layer can sufficiently absorb infrared radiation while remaining thin enough to allow visible light to pass through to the solar cell, thus achieving temperature reduction without compromising electrical performance.

Inventive Principle:

Principle #35Parameter changes

2Temperature

If a cooling layer with thickness of 5 μm to 150 μm is used to absorb far-infrared rays, then temperature control is improved, but manufacturing precision requirements increase

Engineering Contradiction:

Improvesubstrate temperatureVSAvoidthickness control

Core Design Contradiction:

TemperatureVSManufacturing precision

Solution Approach 1:

The cooling layer is implemented as a flexible thin film made of PDMS, which can be applied to the solar cell substrate through coating or lamination processes. This thin film approach allows for effective infrared absorption while maintaining flexibility in manufacturing and application, reducing the need for rigid precision thickness control compared to solid cooling structures.

Inventive Principle:

Principle #30Flexible shells and thin films

Solution Approach 2:

The thickness of the cooling layer is optimized within a specific range (5-150 μm) to balance its cooling effectiveness with light transmission properties. By controlling this parameter, the layer can sufficiently absorb infrared radiation while remaining thin enough to allow visible light to pass through to the solar cell, thus achieving temperature reduction without compromising electrical performance.

Inventive Principle:

Principle #35Parameter changes

3Temperature

If PDMS is used as the cooling layer material due to its infrared absorption properties, then cooling effectiveness is improved, but material cost and selection constraints increase

Engineering Contradiction:

Improvecooling effectivenessVSAvoidmaterial selection

Core Design Contradiction:

TemperatureVSEase of manufacture

Solution Approach 1:

The cooling layer is constructed using a composite material system comprising PDMS as the base polymer and infrared-absorbing particles (such as carbon black, graphite, or metal oxides) dispersed within it. This composite structure enables the layer to absorb far-infrared radiation and convert it to heat, which is then dissipated to reduce the substrate temperature and mitigate LeTID effects.

Inventive Principle:

Principle #40Composite materials

Solution Approach 2:

The thickness of the cooling layer is optimized within a specific range (5-150 μm) to balance its cooling effectiveness with light transmission properties. By controlling this parameter, the layer can sufficiently absorb infrared radiation while remaining thin enough to allow visible light to pass through to the solar cell, thus achieving temperature reduction without compromising electrical performance.

Inventive Principle:

Principle #35Parameter changes

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 cooling layer effectively reduces LeTID, enhancing the long-term stability and output of solar cells by acting as a coolant, thereby minimizing temperature increases and maintaining efficiency over time.

Implementation Method 1

the cooling layer absorbs a far-infrared ray from irradiated sunlight and emits a wavelength of the absorbed far-infrared ray

Methodology Applied

Scientific EffectFar-infrared radiation absorption and emission: Infrared Radiation

Implementation Method 2

utilizing natural radiation cooling to reduce LeTID phenomena

Methodology Applied

Scientific EffectNatural radiation cooling: Thermal Radiation

Data Source

PatentUS11749767B2Solar cell and method for manufacturing the same

Publication Date: 2023.09.05 KOREA UNIV RES & BUSINESS FOUND

AI summary

The inventive concept discloses a solar cell and a method for manufacturing the same. The solar cell includes a semiconductor substrate, an emitter layer disposed on one surface of the substrate, and a cooling layer disposed on one surface of the emitter layer, and the cooling layer absorbs a far-infrared ray from irradiated sunlight and emits a wavelength of the absorbed far-infrared ray.