Hetero Nucleus Growth Stabilizing Zinc Anode for High‑Biosecurity Zinc‑Ion Batteries

Biocompatible devices are widely employed in modernized lives and medical fields in the forms of wearable and implantable devices,raising higher requirements on the battery biocompatibility,high safety,low cost,and excellent electrochemical performance,which become the evaluation criteria toward developing feasible biocompatible batteries.Herein,through conducting the battery implantation tests and leakage scene simulations on New Zealand rabbits,zinc sulfate electrolyte is proved to exhibit higher biosecurity and turns out to be one of the ideal zinc salts for biocompatible zinc-ion batteries(ZIBs).Furthermore,in order to mitigate the notorious dendrite growth and hydrogen evolution in mildly acidic electrolyte as well as improve their operating stability,Sn hetero nucleus is introduced to stabilize the zinc anode,which not only facilitates the planar zinc deposition,but also contributes to higher hydrogen evolution overpotential.Finally,a long lifetime of 1500 h for the symmetrical cell,the specific capacity of 150 mAh g^(-1)under 0.5 A g^(-1)for the Zn-MnO_(2)battery and 212 mAh g^(-1)under 5 A g^(-1)for the Zn—NH4V4O10 battery are obtained.This work may provide unique perspectives on biocompatible ZIBs toward the biosecurity of their cell components.

Zinc-ion hybrid supercapacitors with ultrahigh areal and gravimetric energy densities and long cycling life

Zinc ion hybrid supercapacitor (ZIHSC) with promising energy and power densities is an excellent answer to the ever-growing demand for energy storage devices.The restricted lifespan due to the dendrite formation on metallic zinc (Zn) is one of the main roadblocks.Herein,we investigate the electrochemical capability of oxygen-enriched porous carbon nanofibers (A-CNF) and nitrogen,oxygen-enriched porous carbon nanofibers (N-CNF) cathode materials for structural ZIHSCs.To this end,a series of samples with different chemical compositions (N and O contents) are prepared to present deep insight into the electrochemical mechanism between N/O doping and Zn-ion storage.The as-prepared ZIHSC in the presence of N-CNF cathode and Zn Cl_(2) electrolyte offers a battery-level gravimetric energy density of 143.2 Wh kg^(-1)at a power density of 367.1 W kg^(-1).The free-standing N-CNF electrodes in ZIHSCs enjoy delivering an outstanding areal energy density of 110.4μWh cm^(-2)at 0.24 m W cm^(-2),excellent rate capability,and noticeable cycling stability over 10,000 cycles at 10 A g^(-1)with less than 7%decay.It was also concluded that active pyrrolic N dopants might deliver and facilitate more pseudocapacitance in ZIHSCs than other N configurations,resulting in higher adsorption/desorption and insertion/extraction process of Zn Cl^(+).Taking advantage of the beneficial properties of a free-standing continuous cathode,this novel generation of structural cathode material offers high areal and gravimetric energy densities and mechanical properties in a single zinc-ion-based package.