Influence of BaTiO3 morphology on BaTiO3/P(VDF-HFP) electrolyte for self-charging sodium-ion batteries

The coming era of the Internet of Things urgently demands self-charging power systems with the ability of low-power energy harvesting and energy storage. In this work, we design BaTiO₃ with different morphologies (nanoparticles, nanoplates, and nanowires) to be filled in the P(VDF-HFP) composite. The introduction of NaCl crystal as a template can increase the porosity of the polymer film. A series of flexible self-charging sodium-ion batteries have been assembled using the porous BaTiO₃-P(VDF-HFP)-NaClO₄ film as a piezo-electrolyte. Among those piezo-electrolytes with different morphologies BaTiO₃ filler, self-charging sodium-ion batteries (Na_0.71Co_0.96O₂||Na) with BaTiO₃ nanoplates-P(VDF-HFP) - NaClO₄ as electrolyte exhibit superior self-charging performance with the increased capacity of 1.132 mAh in 100 h under static pressure of 5 N. In addition, the flexible battery was subjected to bending pressure and tapping tests. There is little work investigating the morphology effects of filler on self-charging batteries. This work provides an optimization method for piezo-electrolyte of self-charging sodium-ion batteries.