Influence of the Lithium-Ion Concentration in Electrolytes on the Performance of Dye-Sensitized Photorechargeable Batteries

Abstract

Dye-sensitized photorechargeable batteries (DSPBs) have recently gained attention for realizing energy recycling systems under dim light conditions. However, their performance under high storage efficiency (i.e., the capacity charged within a limited time) for practical application remains to be evaluated. Herein, we varied the lithium (Li)-ion concentration, which plays a dual role as energy charging and storage components, to obtain the optimized energy density of DSPBs. Electrochemical studies showed that the Li-ion concentration strongly affected the resistance characteristics of DSPBs. In particular, increasing the Li-ion concentration improved the output capacity and decreased the output voltage. Consequently, the energy density of the finely optimized DSPB improved from 8.73 to 12.64 mWh/cm 3 when irradiated by a 1000lx indoor light-emitting-diode lamp. These findings on the effects of Li-ion concentrations in electrolytes on the performance of DSPBs represent a step forward in realizing the practical application of DSPBs.

What Makes a Photobattery Light-Rechargeable?

“…We consider two SEs (anodes). The first is LMO (intercalation potential of 3 V vs Li + /Li or 0 V vs SHE) graphitized by ball milling–the surface treatment stabilizes the structure to enable lithium insertion into LMO at 3 V vs Li + . − This is due to the formation of nanosized grains during the ball milling treatment. This results in less anisotropic strain being generated which minimizes cracking due to severe Jahn–Teller distortion in the crystals .…”