In this paper, a tripartite macroscopic physics-based model is presented for analysis of organic solar cells (OSCs) in several aspects. This model is consisting of three sub-models (optical, electric and thermal models) which are also coupled to one another. The electric model estimates the current-voltage characteristic of an OSC considering the voltage-dependent series resistance. The 1-D optical model calculates the optical field all along the device that would be further advantageous in predicting the active layer exciton generation rate (input parameter of the electric model), optical heat generation (input parameter of the thermal model), etc. The 3-D steady-state (SS) resistive thermal model is also capable of determining the device SS temperature, also specifying the role of heat conduction, heat convection and heat radiation. These three models are verified individually with experimental data. The electric model is employed to illustrate the nonlinear series resistance in a typical OSC. The optical and thermal models are also combined to yield an opto-thermal model for thermal analysis of 1-D structured photovoltaic devices. It was found that convection (the air thermal conductivity), radiation and device architecture are three determinative parameters that may considerably alter the device SS temperature. This temperature increase may influence both the device efficiency and lifetime.

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