Light Charging Batteries
The development of reliable off-grid power supplies is essential to power autonomous smart devices as well as to fight energy poverty in developing rural communities. Solar energy has been identified as a key technology for universal electricity access, yet insolation is intermittent and therefore solar cells usually have to be connected to rechargeable batteries or electrochemical capacitors. This increases the cost and complexity of these solutions. To address this issue, our research group is working on the development a number of different battery and capacitor materials that can be recharged directly by light without the need for external solar cells.
Li-Ion Photo-Batteries
We demonstrate that organic–inorganic hybrid perovskites can both generate and store energy at the same time. Integrating these functionalities provides simple autonomous power solutions while retaining capacities of up to 100 mAh/g. More information on these devices can be found here.
Zn-Ion Photo-Batteries
To increase the reliability and reduce the cost of photo-charging batteries, we developed a Zin-Ion battery. The light charging process in these batteries relies on a novel cathode formulation consisting of a mixture of vanadium pentoxide nanofibers mixed with poly(3-hexylthiophene-2,5-diyl) and reduced graphene oxide. These materials offer a good separation of charges as well as ion storage, which allows for direct light charging of the battery. In addition, the proposed zinc-ion batteries are using an aqueous electrolyte resulting in a cost effective and safe solution. Finally, the fabrication of these electrodes is relatively straight forward, which we have demonstrated by fabricating a 100 cm2 pouch cell. More details on these photo batteries can be found here.