Photo-rechargeable Mg-ion cell based on PLA/PVDF film

Mg2+ ion based self-charging prototype polymeric photo-power cell has been developed in a very simple and inexpensive way. Eosin Y/MgCl2/PVA mixed aqueous solution and poly(lactic acid) /polyvinylidene fluoride (3:1) composite film are the main assembling components of the device responsible for photo-electrons generation and storage. According to the study of the photovoltaic performance of the cell, a maximum of ∼1 V is obtained under the light intensity of ∼110 mW/cm2. The storage capacity of the device is evaluated to be ∼4.0 F/m2 with an energy density of ∼0.6 mWh/m2 and a power density of ∼2. 5 W/m2 by analyzing the charging–discharging data of the power cell. The charging–discharging data are also recorded for 20 cyclic performances (one cycle per day) to check the longevity of our fabricated Mg2+ ion system. A series connection of four devices can be used as a photo-power bank, which is able to lightened up commercially available 18 LEDs with high intensity, which ensures practical utilizations.