08822 IUPAC Gold Book - fill factor 10.1351/goldbook.08822 08822 current 1 Ratio of the real maximum output power, \(P_{\rm{max}}\), that can be obtained with an actual solar cell to the product of the open-circuit potential, \(V_{\rm{oc}}\), and short-circuit photocurrent, \(I_{\rm{sc}}\): \[f_{\rm{FF}} = P_{\rm{max}}/V_{\rm{oc}}I_{\rm{sc}}\] The \(P_{\rm{max}}\) value is obtained from the cell volt-ampere characteristic as the maximum of the product \(V\!\cdot\!I = P\). Note that the product \(V_{\rm{oc}}\!\cdot\!I_{\rm{sc}}\) is not a theoretical maximum output power of the cell, since the product is zero at both these values as \(I = 0\) for the open circuit and \(V = 0\) for short circuit. solar cell https://goldbook.iupac.org//terms/view/08875 PAC, 2022, 94, 15. 'Glossary of terms relating to electronic, photonic and magnetic properties of polymers (IUPAC Recommendations 2021)' on page 33 (https://doi.org/10.1515/pac-2020-0501) https://goldbook.iupac.org/terms/view/08822/html https://goldbook.iupac.org/terms/view/08822/json https://goldbook.iupac.org/terms/view/08822/plain Citation: 'fill factor' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351/goldbook.08822 The IUPAC Gold Book is licensed under Creative Commons Attribution-ShareAlike CC BY-SA 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/) for individual terms. If you are interested in licensing the Gold Book for commercial use, please contact the IUPAC Executive Director at executivedirector@iupac.org . The International Union of Pure and Applied Chemistry (IUPAC) is continuously reviewing and, where needed, updating terms in the Compendium of Chemical Terminology (the IUPAC Gold Book). Users of these terms are encouraged to include the version of a term with its use and to check regularly for updates to term definitions that you are using. 2026-04-18T08:58:18+00:00