Over the past decade, significant progress in nano science and nanotechnology has opened new avenues for the development of high-performance photovoltaic cells. At present, a variety of nanostructure-based designs—comprising metals, polymers, and semiconductors—are being explored for photovoltaic applications. Advancements in the understanding of optical and electrical mechanisms governing photovoltaic conversion have been supported by theoretical analyses and modeling studies. Nevertheless, the high fabrication cost and relatively low efficiency of conventional solar photovoltaic cells remain major barriers to their large-scale deployment. One-dimensional (1D) nano materials, in particular, have introduced promising prospects for enhancing photovoltaic performance owing to their unique structural and electronic characteristics. Nanowires, nano rods, and nanotubes exemplify such 1D nanostructures, offering substantial potential to improve photon absorption, electron transport, and charge collection within photovoltaic devices. Graphene, a two-dimensional (2D) atomically thin lattice of carbon arranged in a hexagonal configuration, has emerged as a material of exceptional scientific interest. Its superior mechanical properties are attributed to the sp2-hybridized covalent bonds formed by three of the four valence electrons of each carbon atom with neighboring atoms. The remaining delocalized electron contributes to the remarkable optoelectronic properties of graphene, including its exceptionally high carrier mobility, which surpasses that of many conventional conductive materials. Furthermore, graphene thin films can be fabricated through a range of solution-based processing techniques, such as spin-coating, thereby enabling cost-effective, scalable, and versatile production. In the present study, a graphene-based two-dimensional solar cell is modeled and analyzed using the finite element method (FEM) to investigate its photovoltaic behavior and performance characteristics. It is found that the cell potential is 3.85V, VoC is 4.05V, Load cycle current is 4.25V with the surface temperature as 319K. The battery gets saturated at 1500s with graphene. Meanwhile, lithium battery produces cell potential as 3.05V, VoC is 3.05V, Load cycle current is 3.25V. Thus, grapene shows an improvement of 8% in cell potential, 25% in load current value. Lithium battery used for cell phones has the Qn=3500mAh capacity. In graphene, it is 3958mAh with an improvement of 13%.