Stability of CIGS Solar Cells and Component Materials Evaluated by a Step-Stress Accelerated Degradation Test Method: Preprint

Thumbnail image of item number 1 in: 'Stability of CIGS Solar Cells and Component Materials Evaluated by a Step-Stress Accelerated Degradation Test Method: Preprint'.
Thumbnail image of item number 2 in: 'Stability of CIGS Solar Cells and Component Materials Evaluated by a Step-Stress Accelerated Degradation Test Method: Preprint'.
Thumbnail image of item number 3 in: 'Stability of CIGS Solar Cells and Component Materials Evaluated by a Step-Stress Accelerated Degradation Test Method: Preprint'.
Thumbnail image of item number 4 in: 'Stability of CIGS Solar Cells and Component Materials Evaluated by a Step-Stress Accelerated Degradation Test Method: Preprint'.
Showing 1-4 of 16 pages in this article.

PDF Version Also Available for Download.

Description

A step-stress accelerated degradation testing (SSADT) method was employed for the first time to evaluate the stability of CuInGaSe2 (CIGS) solar cells and device component materials in four Al-framed test structures encapsulated with an edge sealant and three kinds of backsheet or moisture barrier film for moisture ingress control. The SSADT exposure used a 15oC and then a 15% relative humidity (RH) increment step, beginning from 40oC/40%RH (T/RH = 40/40) to 85oC/70%RH (85/70) as of the moment. The voluminous data acquired and processed as of total DH = 3956 h with 85/70 = 704 h produced the following results. The ... continued below

Physical Description

16 p.

Creation Information

Pern, F. J. & Noufi, R. October 1, 2012.

Context

This article is part of the collection entitled: Office of Scientific & Technical Information Technical Reports and was provided by UNT Libraries Government Documents Department to Digital Library, a digital repository hosted by the UNT Libraries. More information about this article can be viewed below.

Who

People and organizations associated with either the creation of this article or its content.

Authors

Sponsor

Publisher

Provided By

UNT Libraries Government Documents Department

Serving as both a federal and a state depository library, the UNT Libraries Government Documents Department maintains millions of items in a variety of formats. The department is a member of the FDLP Content Partnerships Program and an Affiliated Archive of the National Archives.

About | Browse this Partner

Contact Us

Corrections Questions

What

Descriptive information to help identify this article. Follow the links below to find similar items on the Digital Library.

Description

A step-stress accelerated degradation testing (SSADT) method was employed for the first time to evaluate the stability of CuInGaSe2 (CIGS) solar cells and device component materials in four Al-framed test structures encapsulated with an edge sealant and three kinds of backsheet or moisture barrier film for moisture ingress control. The SSADT exposure used a 15oC and then a 15% relative humidity (RH) increment step, beginning from 40oC/40%RH (T/RH = 40/40) to 85oC/70%RH (85/70) as of the moment. The voluminous data acquired and processed as of total DH = 3956 h with 85/70 = 704 h produced the following results. The best CIGS solar cells in sample Set-1 with a moisture-permeable TPT backsheet showed essentially identical I-V degradation trend regardless of the Al-doped ZnO (AZO) layer thickness ranging from standard 0.12 &#956;m to 0.50 &#956;m on the cells. No clear 'stepwise' feature in the I-V parameter degradation curves corresponding to the SSADT T/RH/time profile was observed. Irregularity in I-V performance degradation pattern was observed with some cells showing early degradation at low T/RH < 55/55 and some showing large Voc, FF, and efficiency degradation due to increased series Rs (ohm-cm2) at T/RH &#8805; 70/70. Results of (electrochemical) impedance spectroscopy (ECIS) analysis indicate degradation of the CIGS solar cells corresponded to increased series resistance Rs (ohm) and degraded parallel (minority carrier diffusion/recombination) resistance Rp, capacitance C, overall time constant Rp*C, and 'capacitor quality' factor (CPE-P), which were related to the cells? p-n junction properties. Heating at 85/70 appeared to benefit the CIGS solar cells as indicated by the largely recovered CPE-P factor. Device component materials, Mo on soda lime glass (Mo/SLG), bilayer ZnO (BZO), AlNi grid contact, and CdS/CIGS/Mo/SLG in test structures with TPT showed notable to significant degradation at T/RH &#8805; 70/70. At T/RH = 85/70, substantial blistering of BZO layers on CIGS cell pieces was observed that was not seen on BZO/glass, and a CdS/CIGS sample displayed a small darkening and then flaking feature. Additionally, standard AlNi grid contact was less stable than thin Ni grid contact at T/RH &#8805; 70/70. The edge sealant and moisture-blocking films were effective to block moisture ingress, as evidenced by the good stability of most CIGS solar cells and device components at T/RH = 85/70 for 704 h, and by preservation of the initial blue color on the RH indicator strips. The SSADT experiment is ongoing to be completed at T/RH = 85/85.

Physical Description

16 p.

Source

  • Presented at SPIE Optics + Photonics, 12-16 August 2012, San Diego, California

Language

Item Type

Identifier

Unique identifying numbers for this article in the Digital Library or other systems.

  • Report No.: NREL/CP-5200-54187
  • Grant Number: AC36-08GO28308
  • Office of Scientific & Technical Information Report Number: 1060065
  • Archival Resource Key: ark:/67531/metadc832086

Collections

This article is part of the following collection of related materials.

Office of Scientific & Technical Information Technical Reports

Reports, articles and other documents harvested from the Office of Scientific and Technical Information.

Office of Scientific and Technical Information (OSTI) is the Department of Energy (DOE) office that collects, preserves, and disseminates DOE-sponsored research and development (R&D) results that are the outcomes of R&D projects or other funded activities at DOE labs and facilities nationwide and grantees at universities and other institutions.

About | Browse this Collection

What responsibilities do I have when using this article?

Digital Files

When

Dates and time periods associated with this article.

Creation Date

  • October 1, 2012

Added to The UNT Digital Library

  • May 19, 2016, 9:45 a.m.

Description Last Updated

  • April 3, 2017, 8:37 p.m.

Usage Statistics

When was this article last used?

Yesterday: 0
Past 30 days: 0
Total Uses: 5
More Statistics

Interact With This Article

Here are some suggestions for what to do next.

Start Reading

Thumbnail image of item number 1 in: 'Stability of CIGS Solar Cells and Component Materials Evaluated by a Step-Stress Accelerated Degradation Test Method: Preprint'.
Thumbnail image of item number 2 in: 'Stability of CIGS Solar Cells and Component Materials Evaluated by a Step-Stress Accelerated Degradation Test Method: Preprint'.
Thumbnail image of item number 3 in: 'Stability of CIGS Solar Cells and Component Materials Evaluated by a Step-Stress Accelerated Degradation Test Method: Preprint'.
Thumbnail image of item number 4 in: 'Stability of CIGS Solar Cells and Component Materials Evaluated by a Step-Stress Accelerated Degradation Test Method: Preprint'.

PDF Version Also Available for Download.

Citations, Rights, Re-Use

International Image Interoperability Framework

IIF Logo

We support the IIIF Presentation API

Pern, F. J. & Noufi, R. Stability of CIGS Solar Cells and Component Materials Evaluated by a Step-Stress Accelerated Degradation Test Method: Preprint, article, October 1, 2012; Golden, Colorado. (digital.library.unt.edu/ark:/67531/metadc832086/: accessed October 22, 2018), University of North Texas Libraries, Digital Library, digital.library.unt.edu; crediting UNT Libraries Government Documents Department.