4 andreas schneider, bifi psda, antofagasta (chile) 2015

An overview on crystalline silicon solar cell module defects

Dr Andreas Schneider

International Solar Energy Research Center (ISC) Konstanz GERMANY

Dr Andreas Schneider Workshop Chile January 15th Chile 2015

- How does a crystalline solar module looks like

- Overview on module defects

- What does it mean for Chile

- Outlook and Summary

Outline

2


Crystalline solar modules consist of

Solar modules

3

Source Henkel

- Protection (Longevity) Glass encapsulation foil and backsheet

- MountingIntegrity Frame

- Electrical connection Junction box

- Electrical generator Stringed solar cells

Source Centrotherm


Special requirements for individual concepts

Difficulties for modules

4

- IBC cells

- Soldering is hardly feasible

- Highly UV transparent encapsulant needed

- Bifaciality requires glassglass

- HIT cells

- Perfect water protection required

- Low temperature interconnection needed

- SE cells


- Low stress ribbon (cell to module loss reduction)

Source Centrotherm

Source Meyer Burger

Dr Andreas Schneider Workshop Chile January 15th Chile 2015 5

Overview on cell interconnection

Standard soldering technique Source Komax

High stress application

- gt 200ordmC (for Pb coated ribbon)

- gt 250ordmC (for Pb-free ribbon)

- Bow effect

- Micro cracks due to mechanical stress

Difficult to interconnect thin solar cells (le160microm)

Restrictions to interconnect rear contact solar cells and hetero junction cells

Busbars and pads are a key requirement

Over decades tested and proven interconnection


Corrosion

Frame

Origin

bull Installation leakage currents

bull Installation Mounting screws

bull Materials Frame (Al anodization)

bull Weather Salt acid rain pollution

Consequence

bull Loss of grounding

bull Loss of mech stability


Corrosion

Busing

Consequence

bull Hot spots

bull Loss in module power

Origin

bull Process Impact of water

bull Process Bad soldering

bull Materials Chemical reaction

bull Materials Bad ribbon alloying

bull WeatherTreatment Damages on backsheet foil


Corrosion

Solar cell

Origin






Consequence

bull Hot spots



Corrosion

Junction box

Origin


bull Process Bad potting lid closing

bull Process screwing soldering welding

bull WeatherTreatment Salt acid rain pollution

Damages

Consequence

bull Hot spots fire



Defects Backsheet Material

Defects

Origin

bull Process Insufficient lamination

bull Materials Interlayer delamination

bull Materials Expiry date exceeded storage condition

bull Weather UV level

Consequence

bull Reduction of lifetime


bull Safety risk

Backsheet foilencapsulant


Defects Encapsulation Material

Delamination EVA

Origin


bull Process Contamination


bull Materials Quality defects (chemicals)

bull Weather UV level Consequence



bull Safety risk

Cellencapsulant glassencapsulant



Bubbles

Origin








Cellencapsulant glassencapsulant Backsheet foilencapsulant



Cuts

Origin





bull Weather UV level and thermal stress

Consequence






Decoloration Yellowing Browning

Origin

bull Weather UV level and thermal impact

bull Materials Expiry date exceeded

storage condition


Consequence




Glass

Breakage Origin

bull Weather Extreme thermal impacts

bull Weather Hail wind

bull Materials Chemical contamination

bull Process Mechanical stress

bull Installation Hot spots

bull Installation Mechanical stress

Consequence



bull Safety issue


Junction Box

Defect

Origin

bull Materials J-Box quality

bull Process Quality issues

Consequence



bull Safety issue


Cables Connectors

Defect Origin


bull InstallationTransport Handling


Consequence



bull Safety issue


Bypass diodes

Defect Origin


bull Weather Lightning

bull Materials Broken diode (short)

bull Installation Strong and long shading

Consequence



bull Safety issue


Solar Cell

Defect Origin





Consequence



bull Safety issue


Potential Induced Degradation

Cell Module System Origin

bull Materials PID sensitive cell

bull Materials low resistive EVA

bull Installation Missing grounding

bull Weather Extreme thermalmoisture

Consequence




Process issues

Frame

Gap between frame parts

-gt loss in mech stability

Scratches in frame

-gt corrosion

Problems frame sealing

-gt water ingress

-gt larger leakage currents


Process issues

Cell

Cracks

-gt power loss

-gt hot spots

Soldering issue

-gt power loss

-gt hot spots


Contamination

Solution Cleaning Snow Water


Worst case

RUN Case


What does it mean for Chile

25

- Large UV radiation temperature and temperate changes

- Large irradiation and number of sunhours

- Large impact on soiling

- special requirement on materials (backsheet encapsulant)

- very soft cell interconnection process (cracks etc)

- Lifetime of bypass diode

- Cables box and connectors

- good cleaning procedures


Summary

26

- Standard module concept consist of only few materials which are certified and tested for locations of moderate climates

- Several module defects exist which can lead to early failure and hazardous situations

- Chile requires a module with modified materials processes and quality checks to allow for a lifetime comparable to Europe

ISC Konstanz

research for a sunny future

THANK YOU


- How does a crystalline solar module looks like

- Overview on module defects

- What does it mean for Chile

- Outlook and Summary

Outline

2



Solar modules

3

Source Henkel





Source Centrotherm




4

- IBC cells




- HIT cells



- SE cells



Source Centrotherm

Source Meyer Burger







- Bow effect







Corrosion

Frame

Origin





Consequence




Corrosion

Busing

Consequence

bull Hot spots


Origin







Corrosion

Solar cell

Origin






Consequence

bull Hot spots



Corrosion

Junction box

Origin





Damages

Consequence

bull Hot spots fire




Defects

Origin





Consequence



bull Safety risk




Delamination EVA

Origin








bull Safety risk




Bubbles

Origin











Cuts

Origin






Consequence







Origin



storage condition


Consequence




Glass

Breakage Origin







Consequence



bull Safety issue


Junction Box

Defect

Origin



Consequence



bull Safety issue


Cables Connectors

Defect Origin




Consequence



bull Safety issue


Bypass diodes

Defect Origin





Consequence



bull Safety issue


Solar Cell

Defect Origin





Consequence



bull Safety issue








Consequence




Process issues

Frame



Scratches in frame

-gt corrosion


-gt water ingress



Process issues

Cell

Cracks

-gt power loss

-gt hot spots

Soldering issue

-gt power loss

-gt hot spots


Contamination



Worst case

RUN Case



25










Summary

26




ISC Konstanz


THANK YOU



Solar modules

3

Source Henkel





Source Centrotherm




4

- IBC cells




- HIT cells



- SE cells



Source Centrotherm

Source Meyer Burger







- Bow effect







Corrosion

Frame

Origin





Consequence




Corrosion

Busing

Consequence

bull Hot spots


Origin







Corrosion

Solar cell

Origin






Consequence

bull Hot spots



Corrosion

Junction box

Origin





Damages

Consequence

bull Hot spots fire




Defects

Origin





Consequence



bull Safety risk




Delamination EVA

Origin








bull Safety risk




Bubbles

Origin











Cuts

Origin






Consequence







Origin



storage condition


Consequence




Glass

Breakage Origin







Consequence



bull Safety issue


Junction Box

Defect

Origin



Consequence



bull Safety issue


Cables Connectors

Defect Origin




Consequence



bull Safety issue


Bypass diodes

Defect Origin





Consequence



bull Safety issue


Solar Cell

Defect Origin





Consequence



bull Safety issue








Consequence




Process issues

Frame



Scratches in frame

-gt corrosion


-gt water ingress



Process issues

Cell

Cracks

-gt power loss

-gt hot spots

Soldering issue

-gt power loss

-gt hot spots


Contamination



Worst case

RUN Case



25










Summary

26




ISC Konstanz


THANK YOU




4

- IBC cells




- HIT cells



- SE cells



Source Centrotherm

Source Meyer Burger







- Bow effect







Corrosion

Frame

Origin





Consequence




Corrosion

Busing

Consequence

bull Hot spots


Origin







Corrosion

Solar cell

Origin






Consequence

bull Hot spots



Corrosion

Junction box

Origin





Damages

Consequence

bull Hot spots fire




Defects

Origin





Consequence



bull Safety risk




Delamination EVA

Origin








bull Safety risk




Bubbles

Origin











Cuts

Origin






Consequence







Origin



storage condition


Consequence




Glass

Breakage Origin







Consequence



bull Safety issue


Junction Box

Defect

Origin



Consequence



bull Safety issue


Cables Connectors

Defect Origin




Consequence



bull Safety issue


Bypass diodes

Defect Origin





Consequence



bull Safety issue


Solar Cell

Defect Origin





Consequence



bull Safety issue








Consequence




Process issues

Frame



Scratches in frame

-gt corrosion


-gt water ingress



Process issues

Cell

Cracks

-gt power loss

-gt hot spots

Soldering issue

-gt power loss

-gt hot spots


Contamination



Worst case

RUN Case



25










Summary

26




ISC Konstanz


THANK YOU







- Bow effect







Corrosion

Frame

Origin





Consequence




Corrosion

Busing

Consequence

bull Hot spots


Origin







Corrosion

Solar cell

Origin






Consequence

bull Hot spots



Corrosion

Junction box

Origin





Damages

Consequence

bull Hot spots fire




Defects

Origin





Consequence



bull Safety risk




Delamination EVA

Origin








bull Safety risk




Bubbles

Origin











Cuts

Origin






Consequence







Origin



storage condition


Consequence




Glass

Breakage Origin







Consequence



bull Safety issue


Junction Box

Defect

Origin



Consequence



bull Safety issue


Cables Connectors

Defect Origin




Consequence



bull Safety issue


Bypass diodes

Defect Origin





Consequence



bull Safety issue


Solar Cell

Defect Origin





Consequence



bull Safety issue








Consequence




Process issues

Frame



Scratches in frame

-gt corrosion


-gt water ingress



Process issues

Cell

Cracks

-gt power loss

-gt hot spots

Soldering issue

-gt power loss

-gt hot spots


Contamination



Worst case

RUN Case



25










Summary

26




ISC Konstanz


THANK YOU


Corrosion

Frame

Origin





Consequence




Corrosion

Busing

Consequence

bull Hot spots


Origin







Corrosion

Solar cell

Origin






Consequence

bull Hot spots



Corrosion

Junction box

Origin





Damages

Consequence

bull Hot spots fire




Defects

Origin





Consequence



bull Safety risk




Delamination EVA

Origin








bull Safety risk




Bubbles

Origin











Cuts

Origin






Consequence







Origin



storage condition


Consequence




Glass

Breakage Origin







Consequence



bull Safety issue


Junction Box

Defect

Origin



Consequence



bull Safety issue


Cables Connectors

Defect Origin




Consequence



bull Safety issue


Bypass diodes

Defect Origin





Consequence



bull Safety issue


Solar Cell

Defect Origin





Consequence



bull Safety issue








Consequence




Process issues

Frame



Scratches in frame

-gt corrosion


-gt water ingress



Process issues

Cell

Cracks

-gt power loss

-gt hot spots

Soldering issue

-gt power loss

-gt hot spots


Contamination



Worst case

RUN Case



25










Summary

26




ISC Konstanz


THANK YOU


Corrosion

Busing

Consequence

bull Hot spots


Origin







Corrosion

Solar cell

Origin






Consequence

bull Hot spots



Corrosion

Junction box

Origin





Damages

Consequence

bull Hot spots fire




Defects

Origin





Consequence



bull Safety risk




Delamination EVA

Origin








bull Safety risk




Bubbles

Origin











Cuts

Origin






Consequence







Origin



storage condition


Consequence




Glass

Breakage Origin







Consequence



bull Safety issue


Junction Box

Defect

Origin



Consequence



bull Safety issue


Cables Connectors

Defect Origin




Consequence



bull Safety issue


Bypass diodes

Defect Origin





Consequence



bull Safety issue


Solar Cell

Defect Origin





Consequence



bull Safety issue








Consequence




Process issues

Frame



Scratches in frame

-gt corrosion


-gt water ingress



Process issues

Cell

Cracks

-gt power loss

-gt hot spots

Soldering issue

-gt power loss

-gt hot spots


Contamination



Worst case

RUN Case



25










Summary

26




ISC Konstanz


THANK YOU


Corrosion

Solar cell

Origin






Consequence

bull Hot spots



Corrosion

Junction box

Origin





Damages

Consequence

bull Hot spots fire




Defects

Origin





Consequence



bull Safety risk




Delamination EVA

Origin








bull Safety risk




Bubbles

Origin











Cuts

Origin






Consequence







Origin



storage condition


Consequence




Glass

Breakage Origin







Consequence



bull Safety issue


Junction Box

Defect

Origin



Consequence



bull Safety issue


Cables Connectors

Defect Origin




Consequence



bull Safety issue


Bypass diodes

Defect Origin





Consequence



bull Safety issue


Solar Cell

Defect Origin





Consequence



bull Safety issue








Consequence




Process issues

Frame



Scratches in frame

-gt corrosion


-gt water ingress



Process issues

Cell

Cracks

-gt power loss

-gt hot spots

Soldering issue

-gt power loss

-gt hot spots


Contamination



Worst case

RUN Case



25










Summary

26




ISC Konstanz


THANK YOU


Corrosion

Junction box

Origin





Damages

Consequence

bull Hot spots fire




Defects

Origin





Consequence



bull Safety risk




Delamination EVA

Origin








bull Safety risk




Bubbles

Origin











Cuts

Origin






Consequence







Origin



storage condition


Consequence




Glass

Breakage Origin







Consequence



bull Safety issue


Junction Box

Defect

Origin



Consequence



bull Safety issue


Cables Connectors

Defect Origin




Consequence



bull Safety issue


Bypass diodes

Defect Origin





Consequence



bull Safety issue


Solar Cell

Defect Origin





Consequence



bull Safety issue








Consequence




Process issues

Frame



Scratches in frame

-gt corrosion


-gt water ingress



Process issues

Cell

Cracks

-gt power loss

-gt hot spots

Soldering issue

-gt power loss

-gt hot spots


Contamination



Worst case

RUN Case



25










Summary

26




ISC Konstanz


THANK YOU



Defects

Origin





Consequence



bull Safety risk




Delamination EVA

Origin








bull Safety risk




Bubbles

Origin











Cuts

Origin






Consequence







Origin



storage condition


Consequence




Glass

Breakage Origin







Consequence



bull Safety issue


Junction Box

Defect

Origin



Consequence



bull Safety issue


Cables Connectors

Defect Origin




Consequence



bull Safety issue


Bypass diodes

Defect Origin





Consequence



bull Safety issue


Solar Cell

Defect Origin





Consequence



bull Safety issue








Consequence




Process issues

Frame



Scratches in frame

-gt corrosion


-gt water ingress



Process issues

Cell

Cracks

-gt power loss

-gt hot spots

Soldering issue

-gt power loss

-gt hot spots


Contamination



Worst case

RUN Case



25










Summary

26




ISC Konstanz


THANK YOU



Delamination EVA

Origin








bull Safety risk




Bubbles

Origin











Cuts

Origin






Consequence







Origin



storage condition


Consequence




Glass

Breakage Origin







Consequence



bull Safety issue


Junction Box

Defect

Origin



Consequence



bull Safety issue


Cables Connectors

Defect Origin




Consequence



bull Safety issue


Bypass diodes

Defect Origin





Consequence



bull Safety issue


Solar Cell

Defect Origin





Consequence



bull Safety issue








Consequence




Process issues

Frame



Scratches in frame

-gt corrosion


-gt water ingress



Process issues

Cell

Cracks

-gt power loss

-gt hot spots

Soldering issue

-gt power loss

-gt hot spots


Contamination



Worst case

RUN Case



25










Summary

26




ISC Konstanz


THANK YOU



Bubbles

Origin











Cuts

Origin






Consequence







Origin



storage condition


Consequence




Glass

Breakage Origin







Consequence



bull Safety issue


Junction Box

Defect

Origin



Consequence



bull Safety issue


Cables Connectors

Defect Origin




Consequence



bull Safety issue


Bypass diodes

Defect Origin





Consequence



bull Safety issue


Solar Cell

Defect Origin





Consequence



bull Safety issue








Consequence




Process issues

Frame



Scratches in frame

-gt corrosion


-gt water ingress



Process issues

Cell

Cracks

-gt power loss

-gt hot spots

Soldering issue

-gt power loss

-gt hot spots


Contamination



Worst case

RUN Case



25










Summary

26




ISC Konstanz


THANK YOU



Cuts

Origin






Consequence







Origin



storage condition


Consequence




Glass

Breakage Origin







Consequence



bull Safety issue


Junction Box

Defect

Origin



Consequence



bull Safety issue


Cables Connectors

Defect Origin




Consequence



bull Safety issue


Bypass diodes

Defect Origin





Consequence



bull Safety issue


Solar Cell

Defect Origin





Consequence



bull Safety issue








Consequence




Process issues

Frame



Scratches in frame

-gt corrosion


-gt water ingress



Process issues

Cell

Cracks

-gt power loss

-gt hot spots

Soldering issue

-gt power loss

-gt hot spots


Contamination



Worst case

RUN Case



25










Summary

26




ISC Konstanz


THANK YOU




Origin



storage condition


Consequence




Glass

Breakage Origin







Consequence



bull Safety issue


Junction Box

Defect

Origin



Consequence



bull Safety issue


Cables Connectors

Defect Origin




Consequence



bull Safety issue


Bypass diodes

Defect Origin





Consequence



bull Safety issue


Solar Cell

Defect Origin





Consequence



bull Safety issue








Consequence




Process issues

Frame



Scratches in frame

-gt corrosion


-gt water ingress



Process issues

Cell

Cracks

-gt power loss

-gt hot spots

Soldering issue

-gt power loss

-gt hot spots


Contamination



Worst case

RUN Case



25










Summary

26




ISC Konstanz


THANK YOU


Glass

Breakage Origin







Consequence



bull Safety issue


Junction Box

Defect

Origin



Consequence



bull Safety issue


Cables Connectors

Defect Origin




Consequence



bull Safety issue


Bypass diodes

Defect Origin





Consequence



bull Safety issue


Solar Cell

Defect Origin





Consequence



bull Safety issue








Consequence




Process issues

Frame



Scratches in frame

-gt corrosion


-gt water ingress



Process issues

Cell

Cracks

-gt power loss

-gt hot spots

Soldering issue

-gt power loss

-gt hot spots


Contamination



Worst case

RUN Case



25










Summary

26




ISC Konstanz


THANK YOU


Junction Box

Defect

Origin



Consequence



bull Safety issue


Cables Connectors

Defect Origin




Consequence



bull Safety issue


Bypass diodes

Defect Origin





Consequence



bull Safety issue


Solar Cell

Defect Origin





Consequence



bull Safety issue








Consequence




Process issues

Frame



Scratches in frame

-gt corrosion


-gt water ingress



Process issues

Cell

Cracks

-gt power loss

-gt hot spots

Soldering issue

-gt power loss

-gt hot spots


Contamination



Worst case

RUN Case



25










Summary

26




ISC Konstanz


THANK YOU


Cables Connectors

Defect Origin




Consequence



bull Safety issue


Bypass diodes

Defect Origin





Consequence



bull Safety issue


Solar Cell

Defect Origin





Consequence



bull Safety issue








Consequence




Process issues

Frame



Scratches in frame

-gt corrosion


-gt water ingress



Process issues

Cell

Cracks

-gt power loss

-gt hot spots

Soldering issue

-gt power loss

-gt hot spots


Contamination



Worst case

RUN Case



25










Summary

26




ISC Konstanz


THANK YOU


Bypass diodes

Defect Origin





Consequence



bull Safety issue


Solar Cell

Defect Origin





Consequence



bull Safety issue








Consequence




Process issues

Frame



Scratches in frame

-gt corrosion


-gt water ingress



Process issues

Cell

Cracks

-gt power loss

-gt hot spots

Soldering issue

-gt power loss

-gt hot spots


Contamination



Worst case

RUN Case



25










Summary

26




ISC Konstanz


THANK YOU


Solar Cell

Defect Origin





Consequence



bull Safety issue








Consequence




Process issues

Frame



Scratches in frame

-gt corrosion


-gt water ingress



Process issues

Cell

Cracks

-gt power loss

-gt hot spots

Soldering issue

-gt power loss

-gt hot spots


Contamination



Worst case

RUN Case



25










Summary

26




ISC Konstanz


THANK YOU








Consequence




Process issues

Frame



Scratches in frame

-gt corrosion


-gt water ingress



Process issues

Cell

Cracks

-gt power loss

-gt hot spots

Soldering issue

-gt power loss

-gt hot spots


Contamination



Worst case

RUN Case



25










Summary

26




ISC Konstanz


THANK YOU


Process issues

Frame



Scratches in frame

-gt corrosion


-gt water ingress



Process issues

Cell

Cracks

-gt power loss

-gt hot spots

Soldering issue

-gt power loss

-gt hot spots


Contamination



Worst case

RUN Case



25










Summary

26




ISC Konstanz


THANK YOU


Process issues

Cell

Cracks

-gt power loss

-gt hot spots

Soldering issue

-gt power loss

-gt hot spots


Contamination



Worst case

RUN Case



25










Summary

26




ISC Konstanz


THANK YOU


Contamination



Worst case

RUN Case



25










Summary

26




ISC Konstanz


THANK YOU


Worst case

RUN Case



25










Summary

26




ISC Konstanz


THANK YOU



25










Summary

26




ISC Konstanz


THANK YOU


Summary

26




ISC Konstanz


THANK YOU

ISC Konstanz


THANK YOU

Presentations & Public Speaking

4 andreas schneider, bifi psda, antofagasta (chile) 2015