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Laurence Cuffe
What is the physical significance of Ideality Factor in solar...
Dear Dr.Yong, You are welcome! The conversion efficiency PCE= Isc.Voc FF/ Pi where Pi is the incident solar power. The open circuit voltage is achieved according to your given equation when Isc= Id, where Id is the dark diode current Id= I0 exp (V/nVt). So as you said for fixed value of I0 increasing n one has to increase V for the same Id. Assuming Id=Isc, then as per your scenario Voc will be larger. - This may be not always valid as the FF may decrease with increasing n which means a decrease in PCE from the other side. Another important point is that it is observed that as n increases the reverse saturation current gets larger. So, as n increases normally I0 increases. Best wishes
Dear Dr.Yong, You are welcome! The conversion efficiency PCE= Isc.Voc FF/ Pi where Pi is the incident solar power. The open circuit voltage is achieved according to your given equation when Isc= Id, where Id is the dark diode current Id= I0 exp (V/nVt). So as you said for fixed value of I0 increasing n one has to increase V for the same Id. Assuming Id=Isc, then as per your scenario Voc will be larger. - This may be not always valid as the FF may decrease with increasing n which means a decrease in PCE from the other side. Another important point is that it is observed that as n increases the reverse saturation current gets larger. So, as n increases normally I0 increases. Best wishes
The ideality factor of a diode is a measure of how closely the diode follows the ideal diode equation. The derivation of the simple diode equation uses certain assumption about the cell. In practice, there are second order effects so that the diode does not follow the simple diode equation and the ideality factor provides a way of describing them. Pleae read this link for futher info regarding ideality factor. https://www.sciencedirect.com/topics/engineering/ideality-factor
The ideality factor of a diode is a measure of how closely the diode follows the ideal diode equation. The derivation of the simple diode equation uses certain assumption about the cell. In practice, there are second order effects so that the diode does not follow the simple diode equation and the ideality factor provides a way of describing them. Pleae read this link for futher info regarding ideality factor. https://www.sciencedirect.com/topics/engineering/ideality-factor
Dear Chandra, The ideality factor is indicative of the type of charge carrier recombination that is occurring inside of the diode based on the following chart :
- For SRH, band to band (low level injection): Recombination limited by minority carrier. So, n=1. - For SRH, band to band (high level injection): Recombination limited by both carrier types. So, n=2. - Auger recombination: Two majority and one minority carriers required for recombination. So, n=2/3. - Depletion region (Junction): Two carriers limit recombination. So, n=2. Good luck,
Dear Chandra, The ideality factor is indicative of the type of charge carrier recombination that is occurring inside of the diode based on the following chart :
- For SRH, band to band (low level injection): Recombination limited by minority carrier. So, n=1. - For SRH, band to band (high level injection): Recombination limited by both carrier types. So, n=2. - Auger recombination: Two majority and one minority carriers required for recombination. So, n=2/3. - Depletion region (Junction): Two carriers limit recombination. So, n=2. Good luck,
The ideality factor n is one of the diode I-V characteristics parameters. It is an indicator of the recombination mechanisms ruling inside the diode. If the recombination occurs in the neutral regions of the diode n=1. and if the recombination in the space charge region dominates, n=2. For diodes whose recombination at the hetero face is dominant n can be higher than 2. The ideality factor affects the fill factor of the solar cell and it is so the as n increases the fill factor decreases. Mathematically the dark current of the solar cell= Id= Is exp V/nVt , with Vt is the thermal voltage. For other solar cells irrespective of their structure or theory of operation if their i-v Curve can be be curve fitted by an equation like the above one, then one can equivalently assign an ideality factor of them. Other wise, it is not necessary to describe the I-V curve with with an equation like that given above and therefore no need to define an ideality factor for them. Best wishes
The ideality factor n is one of the diode I-V characteristics parameters. It is an indicator of the recombination mechanisms ruling inside the diode. If the recombination occurs in the neutral regions of the diode n=1. and if the recombination in the space charge region dominates, n=2. For diodes whose recombination at the hetero face is dominant n can be higher than 2. The ideality factor affects the fill factor of the solar cell and it is so the as n increases the fill factor decreases. Mathematically the dark current of the solar cell= Id= Is exp V/nVt , with Vt is the thermal voltage. For other solar cells irrespective of their structure or theory of operation if their i-v Curve can be be curve fitted by an equation like the above one, then one can equivalently assign an ideality factor of them. Other wise, it is not necessary to describe the I-V curve with with an equation like that given above and therefore no need to define an ideality factor for them. Best wishes
Caprioglio, Pietro, Christian M. Wolff, Oskar J. Sandberg, Ardalan Armin, Bernd Rech, Steve Albrecht, Dieter Neher, and Martin Stolterfoht. "On the origin of the ideality factor in perovskite solar cells." Advanced Energy Materials 10, no. 27 (2020): 2000502.
Caprioglio, Pietro, Christian M. Wolff, Oskar J. Sandberg, Ardalan Armin, Bernd Rech, Steve Albrecht, Dieter Neher, and Martin Stolterfoht. "On the origin of the ideality factor in perovskite solar cells." Advanced Energy Materials 10, no. 27 (2020): 2000502.
Dear Dr.Yong, You are welcome! The conversion efficiency PCE= Isc.Voc FF/ Pi where Pi is the incident solar power. The open circuit voltage is achieved according to your given equation when Isc= Id, where Id is the dark diode current Id= I0 exp (V/nVt). So as you said for fixed value of I0 increasing n one has to increase V for the same Id. Assuming Id=Isc, then as per your scenario Voc will be larger. - This may be not always valid as the FF may decrease with increasing n which means a decrease in PCE from the other side. Another important point is that it is observed that as n increases the reverse saturation current gets larger. So, as n increases normally I0 increases. Best wishes
Dear Dr.Yong, You are welcome! The conversion efficiency PCE= Isc.Voc FF/ Pi where Pi is the incident solar power. The open circuit voltage is achieved according to your given equation when Isc= Id, where Id is the dark diode current Id= I0 exp (V/nVt). So as you said for fixed value of I0 increasing n one has to increase V for the same Id. Assuming Id=Isc, then as per your scenario Voc will be larger. - This may be not always valid as the FF may decrease with increasing n which means a decrease in PCE from the other side. Another important point is that it is observed that as n increases the reverse saturation current gets larger. So, as n increases normally I0 increases. Best wishes
The ideality factor n is one of the diode I-V characteristics parameters. The ideality factor is directly related with the recombination order.The ideality factor (also called the emissivity factor) is a fitting parameter that describes how closely the diode's behavior matches that predicted by theory, which assumes the p-n junction of the diode is an infinite plane and no recombination occurs within the space-charge region. It is an indicator of the recombination mechanisms ruling inside the diode. If the recombination occurs in the neutral regions of the diode n=1. And if the recombination in the space charge region dominates, n=2. There are two kinds of ideality factors that can differ from each other. The dark ideality factor is measured in the IV-curve forward direction in the dark. The light ideality factor is determined at the slope of the open-circuit voltage versus the light intensity. In this thesis only the second type is treated. If the ideality factor nid is one, the cell is ideal and at its optimum. The ’ideal’ ideality factor is always larger than one. The ideality factor changes between one and two depending on the light intensity, in order to obtain meaningful ideality factor values between 1 and 2 cell is advised to be normalized. If SRH recombination is dominant the recombination order is 1 and the ideality factor is 2.
Significance The ideality factor n under the standard illumination can indicate a nearly ideal diode; the rise in n with the decrease of intensity is physically suggesting a partial shift in the forward current mechanism from asymmetric recombination near the metallurgical junction, to more symmetric recombination distribution over the depletion region. Therefore, the space charge recombination is more contributive at low intensities; the variation of n is attributed to the bulk and surface recombination mechanisms at high intensities. The IV curve of a solar cell can be described analytically using the ideality factor. The slope of VOC is measured to determine the ideality factor. This is used for practical solar cell application.
Ideality Values for ferroelectric For feroolectric PV, The ideality factor (N) was in the range of 1.3–3.3. There are technical drawbacks for their practical solar cell applications.
The ideality factor n is one of the diode I-V characteristics parameters. The ideality factor is directly related with the recombination order.The ideality factor (also called the emissivity factor) is a fitting parameter that describes how closely the diode's behavior matches that predicted by theory, which assumes the p-n junction of the diode is an infinite plane and no recombination occurs within the space-charge region. It is an indicator of the recombination mechanisms ruling inside the diode. If the recombination occurs in the neutral regions of the diode n=1. And if the recombination in the space charge region dominates, n=2. There are two kinds of ideality factors that can differ from each other. The dark ideality factor is measured in the IV-curve forward direction in the dark. The light ideality factor is determined at the slope of the open-circuit voltage versus the light intensity. In this thesis only the second type is treated. If the ideality factor nid is one, the cell is ideal and at its optimum. The ’ideal’ ideality factor is always larger than one. The ideality factor changes between one and two depending on the light intensity, in order to obtain meaningful ideality factor values between 1 and 2 cell is advised to be normalized. If SRH recombination is dominant the recombination order is 1 and the ideality factor is 2.
Significance The ideality factor n under the standard illumination can indicate a nearly ideal diode; the rise in n with the decrease of intensity is physically suggesting a partial shift in the forward current mechanism from asymmetric recombination near the metallurgical junction, to more symmetric recombination distribution over the depletion region. Therefore, the space charge recombination is more contributive at low intensities; the variation of n is attributed to the bulk and surface recombination mechanisms at high intensities. The IV curve of a solar cell can be described analytically using the ideality factor. The slope of VOC is measured to determine the ideality factor. This is used for practical solar cell application.
Ideality Values for ferroelectric For feroolectric PV, The ideality factor (N) was in the range of 1.3–3.3. There are technical drawbacks for their practical solar cell applications.
Hello everyone, For more details on the ideality factor, I recommend these articles: A junction characterization for microelectronic devices quality and reliability 10.1016/j.microrel.2007.06.002 Good luck
Hello everyone, For more details on the ideality factor, I recommend these articles: A junction characterization for microelectronic devices quality and reliability 10.1016/j.microrel.2007.06.002 Good luck
Dear Dr.Yong,
You are welcome!
The conversion efficiency PCE= Isc.Voc FF/ Pi where Pi is the incident solar power.
The open circuit voltage is achieved according to your given equation when Isc= Id, where Id is the dark diode current Id= I0 exp (V/nVt).
So as you said for fixed value of I0 increasing n one has to increase V for the same Id. Assuming Id=Isc, then as per your scenario Voc will be larger.
- This may be not always valid as the FF may decrease with increasing n which means a decrease in PCE from the other side.
Another important point is that it is observed that as n increases the reverse saturation current gets larger. So, as n increases normally I0 increases.
Best wishes
Dear Dr.Yong,
You are welcome!
The conversion efficiency PCE= Isc.Voc FF/ Pi where Pi is the incident solar power.
The open circuit voltage is achieved according to your given equation when Isc= Id, where Id is the dark diode current Id= I0 exp (V/nVt).
So as you said for fixed value of I0 increasing n one has to increase V for the same Id. Assuming Id=Isc, then as per your scenario Voc will be larger.
- This may be not always valid as the FF may decrease with increasing n which means a decrease in PCE from the other side.
Another important point is that it is observed that as n increases the reverse saturation current gets larger. So, as n increases normally I0 increases.
Best wishes
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Dear sir
How to find a series and shunt resistance in two diode solar model?
Dear sir
How to find a series and shunt resistance in two diode solar model?
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The ideality factor of a diode is a measure of how closely the diode follows the ideal diode equation. The derivation of the simple diode equation uses certain assumption about the cell. In practice, there are second order effects so that the diode does not follow the simple diode equation and the ideality factor provides a way of describing them.
Pleae read this link for futher info regarding ideality factor.
https://www.sciencedirect.com/topics/engineering/ideality-factor
The ideality factor of a diode is a measure of how closely the diode follows the ideal diode equation. The derivation of the simple diode equation uses certain assumption about the cell. In practice, there are second order effects so that the diode does not follow the simple diode equation and the ideality factor provides a way of describing them.
Pleae read this link for futher info regarding ideality factor.
https://www.sciencedirect.com/topics/engineering/ideality-factor
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Thank you!
Thank you!
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Dear Chandra,
The ideality factor is indicative of the type of charge carrier recombination that is occurring inside of the diode based on the following chart :
- For SRH, band to band (low level injection): Recombination limited by minority carrier. So, n=1.
- For SRH, band to band (high level injection): Recombination limited by both carrier types. So, n=2.
- Auger recombination: Two majority and one minority carriers required for recombination. So, n=2/3.
- Depletion region (Junction): Two carriers limit recombination. So, n=2.
Good luck,
Dear Chandra,
The ideality factor is indicative of the type of charge carrier recombination that is occurring inside of the diode based on the following chart :
- For SRH, band to band (low level injection): Recombination limited by minority carrier. So, n=1.
- For SRH, band to band (high level injection): Recombination limited by both carrier types. So, n=2.
- Auger recombination: Two majority and one minority carriers required for recombination. So, n=2/3.
- Depletion region (Junction): Two carriers limit recombination. So, n=2.
Good luck,
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I agree Idris Bouchama
I agree Idris Bouchama
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The ideality factor n is one of the diode I-V characteristics parameters. It is an indicator of the recombination mechanisms ruling inside the diode. If the recombination occurs in the neutral regions of the diode n=1. and if the recombination in the space charge region dominates, n=2. For diodes whose recombination at the hetero face is dominant n can be higher than 2. The ideality factor affects the fill factor of the solar cell and it is so the as n increases the fill factor decreases.
Mathematically the dark current of the solar cell= Id= Is exp V/nVt , with Vt is the thermal voltage.
For other solar cells irrespective of their structure or theory of operation if their i-v Curve can be be curve fitted by an equation like the above one, then one can equivalently assign an ideality factor of them.
Other wise, it is not necessary to describe the I-V curve with with an equation like that given above and therefore no need to define an ideality factor for them.
Best wishes
The ideality factor n is one of the diode I-V characteristics parameters. It is an indicator of the recombination mechanisms ruling inside the diode. If the recombination occurs in the neutral regions of the diode n=1. and if the recombination in the space charge region dominates, n=2. For diodes whose recombination at the hetero face is dominant n can be higher than 2. The ideality factor affects the fill factor of the solar cell and it is so the as n increases the fill factor decreases.
Mathematically the dark current of the solar cell= Id= Is exp V/nVt , with Vt is the thermal voltage.
For other solar cells irrespective of their structure or theory of operation if their i-v Curve can be be curve fitted by an equation like the above one, then one can equivalently assign an ideality factor of them.
Other wise, it is not necessary to describe the I-V curve with with an equation like that given above and therefore no need to define an ideality factor for them.
Best wishes
More
VOTE
Caprioglio, Pietro, Christian M. Wolff, Oskar J. Sandberg, Ardalan Armin, Bernd Rech, Steve Albrecht, Dieter Neher, and Martin Stolterfoht. "On the origin of the ideality factor in perovskite solar cells." Advanced Energy Materials 10, no. 27 (2020): 2000502.
Caprioglio, Pietro, Christian M. Wolff, Oskar J. Sandberg, Ardalan Armin, Bernd Rech, Steve Albrecht, Dieter Neher, and Martin Stolterfoht. "On the origin of the ideality factor in perovskite solar cells." Advanced Energy Materials 10, no. 27 (2020): 2000502.
More
VOTE
Dear Dr.Yong,
You are welcome!
The conversion efficiency PCE= Isc.Voc FF/ Pi where Pi is the incident solar power.
The open circuit voltage is achieved according to your given equation when Isc= Id, where Id is the dark diode current Id= I0 exp (V/nVt).
So as you said for fixed value of I0 increasing n one has to increase V for the same Id. Assuming Id=Isc, then as per your scenario Voc will be larger.
- This may be not always valid as the FF may decrease with increasing n which means a decrease in PCE from the other side.
Another important point is that it is observed that as n increases the reverse saturation current gets larger. So, as n increases normally I0 increases.
Best wishes
Dear Dr.Yong,
You are welcome!
The conversion efficiency PCE= Isc.Voc FF/ Pi where Pi is the incident solar power.
The open circuit voltage is achieved according to your given equation when Isc= Id, where Id is the dark diode current Id= I0 exp (V/nVt).
So as you said for fixed value of I0 increasing n one has to increase V for the same Id. Assuming Id=Isc, then as per your scenario Voc will be larger.
- This may be not always valid as the FF may decrease with increasing n which means a decrease in PCE from the other side.
Another important point is that it is observed that as n increases the reverse saturation current gets larger. So, as n increases normally I0 increases.
Best wishes
More
VOTE
Dear Chandrabhal,
The ideality factor n is one of the diode I-V characteristics parameters. The ideality factor is directly related with the recombination order.The ideality factor (also called the emissivity factor) is a fitting parameter that describes how closely the diode's behavior matches that predicted by theory, which assumes the p-n junction of the diode is an infinite plane and no recombination occurs within the space-charge region. It is an indicator of the recombination mechanisms ruling inside the diode. If the recombination occurs in the neutral regions of the diode n=1. And if the recombination in the space charge region dominates, n=2. There are two kinds of ideality factors that can differ from each other. The dark ideality factor is measured in the IV-curve forward direction in the dark. The light ideality factor is determined at the slope of the open-circuit voltage versus the light intensity. In this thesis only the second type is treated. If the ideality factor nid is one, the cell is ideal and at its optimum. The ’ideal’ ideality factor is always larger than one. The ideality factor changes between one and two depending on the light intensity, in order to obtain meaningful ideality factor values between 1 and 2 cell is advised to be normalized. If SRH recombination is dominant the recombination order is 1 and the ideality factor is 2.
Significance
The ideality factor n under the standard illumination can indicate a nearly ideal diode; the rise in n with the decrease of intensity is physically suggesting a partial shift in the forward current mechanism from asymmetric recombination near the metallurgical junction, to more symmetric recombination distribution over the depletion region. Therefore, the space charge recombination is more contributive at low intensities; the variation of n is attributed to the bulk and surface recombination mechanisms at high intensities. The IV curve of a solar cell can be described analytically using the ideality factor. The slope of VOC is measured to determine the ideality factor. This is used for practical solar cell application.
Ideality Values for ferroelectric
For feroolectric PV, The ideality factor (N) was in the range of 1.3–3.3. There are technical drawbacks for their practical solar cell applications.
Ashish
Dear Chandrabhal,
The ideality factor n is one of the diode I-V characteristics parameters. The ideality factor is directly related with the recombination order.The ideality factor (also called the emissivity factor) is a fitting parameter that describes how closely the diode's behavior matches that predicted by theory, which assumes the p-n junction of the diode is an infinite plane and no recombination occurs within the space-charge region. It is an indicator of the recombination mechanisms ruling inside the diode. If the recombination occurs in the neutral regions of the diode n=1. And if the recombination in the space charge region dominates, n=2. There are two kinds of ideality factors that can differ from each other. The dark ideality factor is measured in the IV-curve forward direction in the dark. The light ideality factor is determined at the slope of the open-circuit voltage versus the light intensity. In this thesis only the second type is treated. If the ideality factor nid is one, the cell is ideal and at its optimum. The ’ideal’ ideality factor is always larger than one. The ideality factor changes between one and two depending on the light intensity, in order to obtain meaningful ideality factor values between 1 and 2 cell is advised to be normalized. If SRH recombination is dominant the recombination order is 1 and the ideality factor is 2.
Significance
The ideality factor n under the standard illumination can indicate a nearly ideal diode; the rise in n with the decrease of intensity is physically suggesting a partial shift in the forward current mechanism from asymmetric recombination near the metallurgical junction, to more symmetric recombination distribution over the depletion region. Therefore, the space charge recombination is more contributive at low intensities; the variation of n is attributed to the bulk and surface recombination mechanisms at high intensities. The IV curve of a solar cell can be described analytically using the ideality factor. The slope of VOC is measured to determine the ideality factor. This is used for practical solar cell application.
Ideality Values for ferroelectric
For feroolectric PV, The ideality factor (N) was in the range of 1.3–3.3. There are technical drawbacks for their practical solar cell applications.
Ashish
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Dear Shandra,
Please read the following sites for more details :
- https://www.pveducation.org/pvcdrom/solar-cell-operation/ideality-factor
- https://www.sciencedirect.com/topics/engineering/ideality-factor
Good luck
Dear Shandra,
Please read the following sites for more details :
- https://www.pveducation.org/pvcdrom/solar-cell-operation/ideality-factor
- https://www.sciencedirect.com/topics/engineering/ideality-factor
Good luck
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Hello everyone,
For more details on the ideality factor, I recommend these articles:
A junction characterization for microelectronic devices quality and reliability 10.1016/j.microrel.2007.06.002
Good luck
Hello everyone,
For more details on the ideality factor, I recommend these articles:
A junction characterization for microelectronic devices quality and reliability 10.1016/j.microrel.2007.06.002
Good luck
More
VOTE