RESUMEN
Dendrite growth and corrosion of Zn metal anodes result in the limited reversibility of aqueous Zn metal batteries (ZMBs), hindering their prospects as large-scale energy storage devices. Inspired by the similarity of conventional electroplating industrial engineering and Zn deposition in ZMBs, we tend to utilize a low-cost leveling agent (LEA), 1,4-butynediol, to level the Zn deposition. Combining theoretical with in situ experimental characterizations, the preferential adsorption of LEA molecules on different lattice planes can contribute to crystallographic orientation manipulation of the (002) plane, causing good inhibition of dendrite growth. Additionally, the adsorption of LEA molecules on the Zn surface can also prevent undesirable corrosion. Endowed with these merits, symmetric cells and full cells with the LEA additive achieve improved stability and reversibility. This work provides new inspiration for introducing traditional electroplating additives into high-performance ZMBs and gives researchers a direction for choosing electrolyte additives, which also has potential to be applied to other metal anodes.
RESUMEN
Aqueous Zn metal batteries have attracted extensive attention due to their intrinsic advantages. However, zinc ions tend to deposit irregularly, seriously depleting the capacity and stability of the battery. The construction of zincophilic sites can effectively regulate the nucleation and growth of Zn, but there is a defect that these sites will be covered with gradual failure after long-term cycling. Here, in combination with the sustained-compensated strategy, interfacial zincophilic sites are continuously constructed, thus effectively avoiding the threat of dendrites and improving the electrochemical performance. Impressively, at 10 mA cm-2 and 5 mAh cm-2, the protected Zn metal exhibits excellent cycling stability over 2000 cycles in the Zn//Zn battery. Moreover, even the cathode mass loading is considerably high (35 mg cm-2), and the Zn//NVO full cell significantly outperforms with high areal capacity (up to 4 mAh cm-2). This novel strategy provides a direction for the development of high-capacity aqueous batteries.
RESUMEN
The industrialization of aqueous zinc-ion batteries (AZIBs) is hampered by poor-performance separators. Filter paper (FP), with mature production processes and low prices, has potential as a separator. However, its swelling and decline of mechanical durability in aqueous environments make it easily punctured by dendrites. In response, wet strength promotion is proposed to toughen FP for robust AZIBs, termed wet-strengthened FP (WSFP). Due to the self-cross-linking network formed on cellulose fibers, water molecules are prevented from easily permeating and disrupting the hydrogen bonds between cellulose molecules. Moreover, the positively charged network can anchor SO42-, thus increasing the Zn2+ transference number and facilitating uniform zinc deposition. Surprisingly, the half and full cells with the WSFP separator present much more stable cycling than untreated FP and glass fiber (GF) separators. These results suggest that robust and low-cost WSFP separators provide a new avenue for the development of high-performance AZIBs with potential for commercialization.
RESUMEN
Side reactions caused by highly active water molecules, including severe corrosion, hydrogen evolution, and dendrite growth, are impediments to the advancement of aqueous zinc ion batteries (ZIBs). Here, inspired by the pivotal role of plant fibers to prevent dehydration in nature, we designed a unique water-retaining plant fiber (WRPF) separator with strong hygroscopic ability to adsorb and trap water molecules. Elaborated theoretical and experimental characterizations prove that high-activity water could be sequestered by a WRPF separator, alleviating water-induced side reactions and accelerating the desolvation of hydrate Zn2+. Prominently, reversible Zn plating and stripping could be realized in Zn//Cu batteries. Even with elevated cathodic mass loading (21.94 mg cm-2), the Zn//VS2 full cell delivers high areal capacity 3.3 mAh cm-2 and well-maintained stability. The present study offers a versatile design strategy for separators using nature-inspired materials, aiming to address the challenging issue of "water" and achieve ultrastable interfacial chemistry of Zn anode.
RESUMEN
Despite the numerous advantages of aqueous Zn batteries, their practical application under cryogenic conditions is hindered by the freezing of the electrolyte because the abundance of hydrogen bonds (H-bonds) between H2O molecules drives the aqueous system to transform to an orderly frozen structure. Here, a design of H-bond interactions based on the guiding ideology of "strong replaces weak" is proposed. The strong H-bonds formed between introduced eutectic components and water molecules break down the weak H-bonds in the original water molecule network, which contributes to an ultralow freezing point and a high ionic conductivity of 1.7 mS cm-1 at -40 °C. Based on multiperspective theoretical simulations and tailor-made in situ cooling Raman characterizations, it has been demonstrated that substituting weak H-bonds with strong H-bonds facilitates the structural reshaping of Zn2+ solvation and remodeling of the H-bond network in the electrolyte. Endowed with this advantage, reversible and stable Zn plating/stripping behaviors could be realized at -40 °C, and the full cells display a high discharge capacity (200 mA h g-1) at -40 °C with â¼75% capacity retention after 1000 cycles. This study will expand the design philosophy of antifreezing aqueous electrolytes and provide a perspective to promote the adoption of Zn metal batteries for cryogenic environment large-scale energy storage.