Uniform Zn Deposition Achieved by Conductive Carbon Additive for Zn Anode in Zinc‐Ion Hybrid Supercapacitors

Abstract

The nonuniform zinc nucleation process on the surface of zinc metal anodes is known to result in irreversible dendrite growth, which brings the risk of short circuit for the zinc‐ion hybrid supercapacitor (ZIHS). Herein, a conductive carbon−zinc composite anode with dense active sites is reported to achieve controllable dendrite growth. This unique modified anode in the ZIHS enables extremely low polarization (47 mV) in the symmetric battery test and delivers excellent application performance (capacity retention of 97.7% for 10 000 cycles). In addition, the changes in crystallographic orientation and morphological characteristics of the zinc electrode during deposition are observed by ex situ analysis. The improved zinc nucleation pattern of the modified anode verifies that the carbon additive can significantly facilitate isotropy in Zn deposition. Such a successful application of this economic and expandable modification strategy shows that carbon additives have significant potential in improving the stability of the anode.

Inducing the Preferential Growth of Zn (002) Plane for Long Cycle Aqueous Zn‐Ion Batteries

“…It can be found that whether at low current density and capacity or high current density and capacity, the cumulative capacity in this work is superior. It means that the method of inducing preferential growth of (002) plane by using BMIm + ion as an additive is very competitive with other methods, including optimizing the separator, [14,15] modifying coating layers, [16][17][18][19][20][21][22] using other additives, [11,[23][24][25][26][27][28] and processing/heating treatment of the Zn anode. [12,13,29] Besides, the rate performance (Figure S19, Supporting Information) of Zn||Zn symmetric cells cycled in Blank and 0.02 m BMIm + shows that the cell cycled in 0.02 m BMIm + can achieve extremely stable Zn 2+ plating/stripping behavior at various current densities (0.5-10 mA cm −2 ).…”

“…It is worth noting that the preferential growth of ( 105), (103), and (002) planes can form a compact deposition layer to inhibit corrosion and H 2 evolution to a certain extent. [12,13] Therefore, reasonable manipulation of crystal orientation is of great significance for AZIBs.Up to now, the methods of manipulating crystal orientation in AZIBs mainly include optimizing the separator, [14,15] modifying coating layers, [16][17][18][19][20][21][22] using electrolyte additives, [11,[23][24][25][26][27][28] and processing/heating treatment of the Zn anode. [12,13,29] In the above methods, using electrolyte additives is much attractive because of its convenience and cost-effectiveness.…”

“…Up to now, the methods of manipulating crystal orientation in AZIBs mainly include optimizing the separator, [14,15] modifying coating layers, [16][17][18][19][20][21][22] using electrolyte additives, [11,[23][24][25][26][27][28] and processing/heating treatment of the Zn anode. [12,13,29] In the above methods, using electrolyte additives is much attractive because of its convenience and cost-effectiveness.…”

Dendrite-free Zn anode enabled by anionic surfactant-induced horizontal growth for highly-stable aqueous Zn-ion pouch cells

“…The pouch-type Zn8VOH full cell exhibited an impressive initial capacity of 18.7 mA h and a high capacity retention of 82.8% after 200 cycles. Both the cycling performance and rate capability of Zn8Zn symmetric cells are among the highest reported to date using different electrolyte additives to regulate the preferred crystallographic orientation, [22][23][24][25][26][27] highlighting the promising potential of the SPS additive for practical applications.…”

A Zinc–Bromine Battery with Deep Eutectic Electrolytes

“…It has been reported that the surface oxygen‐containing functional groups in carbon materials provide the surface with high zicophilicity, resulting in a reduction of the Zn nucleation overpotential and well‐dispersed Zn nuclei over the carbon surface. [ 46 , 47 , 48 , 49 , 50 ] The uniform Zn deposit morphology would be attributed to the oxygen‐containing surface defects (Figure S15 , Supporting Information) and the large surface area of the 3D structured CC.…”