Storage of Electrons into Chemical Bonds: Towards Molecular Solar Electrical Batteries

Introduction

While photovoltaics has observed rapid growth in the last decades and the utilization of solar energy becomes an ever-growing part of the total electricity produced by mankind, the lack of control over electrical output caused by fluctuation of solar irradiance is an inevitable drawback of the mass use of solar cells.

Solar Batteries as a Solution

Solar batteries, addressing the intermittent production of solar energy, offer an elegant solution without the need for electricity transport and redistribution. In most examples, solar cells are combined with rechargeable batteries (e.g., Li-ion, Pb), which increases the total weight and cost and leads to electricity losses.

Molecular-Based Storage Approaches

The approaches for molecular-based storage of light energy, solar thermal batteries, exploit photoswitching molecules (solar fuels) that generate heat upon thermal back isomerization. To this date, no molecular approach for solar energy storage and subsequent direct generation of electric current exists because this requires the development of light-activatable molecules capable of hysteric electron storage and release.

SOLBATT's Development Goals

SOLBATT develops molecular systems for the transformation of light energy into chemical bonds and their subsequent transformation to electric current. It uses fully organic redox-driven molecular switches that reversibly form an electron-storing bond upon the redox process and combines them with suitable redox-active partners that facilitate photoinduced electron transfer.

Key Contributions of SOLBATT

SOLBATT aims to achieve the following:

1. Improve our understanding of electron storage into chemical bonds and their subsequent release.
2. Deliver redox-responsive molecular systems that can be charged or discharged upon external stimulus.
3. Establish design principles for photoactive redox materials suitable for use in organic solar cells.

Conclusion

Ultimately, SOLBATT takes the vital step in finding a solution to a challenging issue: combining organic solar cells with electron storage materials for solar electric batteries buffering the inherent fluctuations in solar electricity production.