Investigation on Open-Circuit Voltage of an Efficiency-Boosting Solar Cell Technique Featuring V-Configuration

Jianming Li

doi:10.4236/nr.2021.1212026

Abstract

The V-Shaped Module (VSM) solar cell technology, which breaks the traditional concept of solar cell system, has been proven to enhance power conversion efficiency of some solar cells and has offered opportunities to increase generation power densities in area-limited applications. Compared to a planar cell system, the VSM has an additional opportunity to absorb photons and taps the potential of solar cells. In this study, the VSM, the proposed common technique enhancing efficiencies of various solar cells, was investigated by using commercially available multi-crystalline silicon solar cells. The VSM technique enables the efficiencies of the multi-crystalline silicon cells to increase from 13.4% to 20.2%, giving an efficiency boost of 51%. Though the efficiency of the cells increases, the open-circuit voltage of the cells decreases owing to the VSM technique. Furthermore, the obvious reduction in open-circuit voltage in the VSM was found and the phenomenon is explained for the first time.

Highlights

The V-Shaped Module (VSM) technique, one kind of three-dimension (3D) solar cell structure, has been proven to enhance power conversion efficiency (η) of monocrystalline silicon solar cells and has led to an increase of 31% in η [1]
The obvious reduction in open-circuit voltage in the VSM was found and the phenomenon is explained for the first time
To explain the efficiency boost due to the VSM technique, the following three mechanisms are proposed

Summary

Introduction

The V-Shaped Module (VSM) technique, one kind of three-dimension (3D) solar cell structure, has been proven to enhance power conversion efficiency (η) of monocrystalline silicon solar cells and has led to an increase of 31% in η [1]. The VSM technique can increase the generation power density of polycrystalline solar cells [2]. The VSM arrays made of commercially available silicon solar cells were tested under direct sunlight illumination in California, USA and the experimental characterizations showed that “the V-groove array obtains the highest generated electrical power densities at mid-day hours” [4]. The VSM technique offers opportunities to increase generation power densities in area-limited applications such as concentrator cells, photodetectors, and solar-powered vehicles illustrated in [5], and could find an application combined with an artificial phototropic system based on nanostructured polymers [6]. The experimental data achieved at Stanford University have demonstrated that VSM leads to the reduction in the open-circuit voltage (Voc) of organic solar cells [8]. This work was planned in detail to investigate the Voc of VSM by employing commercially available multicrystalline silicon solar cells

Experimental Details

Results and Discussion

Conclusion