Long-Life Aqueous Zn–I₂ Battery Enabled by a Low-Cost Multifunctional Zeolite Membrane Separator

Abstract

Aqueous zinc iodide (Zn−I 2 ) batteries are promising large-scale energy-storage devices. However, the uncontrollable diffuse away/shuttle of soluble I 3 − leads to energy loss (low Coulombic efficiency, CE), and poor reversibility (self-discharge). Herein, we employ an ordered framework window within a zeolite molecular sieve to restrain I 3 − crossover and prepare zeolite molecular sieve particles into compact, large-scale, and flexible membranes at the engineering level. The as-prepared membrane can confine I 3 − within the catholyte region and restrain its irreversible escape, which is proved via space-resolution and electrochemical in situ time-resolution Raman technologies. As a result, overcharge/self-discharge and Zn corrosion are effectively controlled by zeolite separator. After replacing the typically used glass fiber separator to a zeolite membrane, the CE of Zn−I 2 battery improves from 78.9 to 98.6% at 0.2 A/g. Besides, after aging at the fully charged state for 5.0 h, self-discharge is restrained and CE is enhanced from 44.0 to 85.65%. Moreover, the Zn−I 2 cell maintains 91.0% capacity over 30,000 cycles at 4.0 A/g.

Restraining Shuttle Effect in Rechargeable Batteries by Multifunctional Zeolite Coated Separator

“…Zeolite powders are commonly used to scavenge H 2 O from electrolytes in order to diminish the concentration of H 2 O within, which has been widely reported in many studies. [ 2c,16b,19–20 ] The H 2 O content of commercial electrolyte and the aged electrolyte is 55 and 316 ppm, respectively. After immersion of 1 mg activated zeolite powder in 50 mL aged electrolyte resulted in a reduction of the H 2 O content from 316 to 51 ppm (Figure 3b), indicating that zeolite can act as an effective H 2 O scavenger to reduce residual H 2 O in electrolyte and, consequently, resist the damage of residual H 2 O in electrolyte towards battery system.…”

“…By following this designed route, the zeolite molecular sieve (Na 12 (AlO 2 ) 12 (SiO 2 ) 12 ·xH 2 O) with framework window size of 4 Å can separate/trap soluble matters on cathode side, thereby improving battery performance ( Figure a). [ 16 ] Zeolite coated separators (Zeolite@celgard) were fabricated via coating a thoroughly mixed slurry of zeolite powder and polyvinylidene difluoride (PVDF) on celgard separator, which delivers grid‐scale preparation and flexibilities features (Figure 1b; Figure S3, Supporting Information). The current celgard separator used in non‐aqueous metal ion batteries has an accessible channel for crossover of soluble species due to its mesoporous morphology (scanning electron microscope (SEM) images in Figure S4, Supporting Information).…”

Rechargeable Iodine Batteries: Fundamentals, Advances, and Perspectives

“…The Zn-BTC membrane can effectively block the migration of I 3 – in the electrolyte and regulate the electrolyte solvation, thus enabling suppressed shutting effects and restrained side reactions on the Zn anode. In 2022, the low-cost zeolite molecular sieve with a porous framework was reported to have similar effects to Zn-BTC MOF by the same group, demonstrating the availability of functional separators in large-scale applications …”

“…In 2022, the low-cost zeolite molecular sieve with a porous framework was reported to have similar effects to Zn-BTC MOF by the same group, demonstrating the availability of functional separators in large-scale applications. 98 Generally, introducing an iodine host with physical adsorption and chemical interaction immobilizes iodine species, thus enabling the long-term stability of RIBs. The carbon-based materials with physical adsorption can provide a conductive network to promote faster kinetics, while the insufficient interaction cannot totally prevent the shuttle of polyiodides.…”

Enhanced Copolymer Gel Modified by Dual Surfactants for Flexible Zinc–Air Batteries

“…With the increasing prosperity of wearable energy consumption equipment, the design and manufacture of soft batteries with considerable performance have become an important research direction of energy supply. − As a new kind of green battery system, metal–air batteries are widely favored by more and more researchers and scholars. − Zinc–air batteries are increasingly favored in the field of emerging batteries because of the high specific energy (1086 W h kg –1 ) and safety. − The intrinsic structure and characteristics of the gel matrix make it an ideal electrolyte material for flexible batteries. − Considering the instability and uncontrollable factors of the batteries in the actual working environment, the gel electrolyte must have good physicochemical characteristics and variable environmental adaptability. , Nevertheless, due to the brittleness and fragility of conventional gel polymers, the assembled flexible energy storage equipment exhibits poor mechanical properties, and the performance attenuation is serious in the deformation state, so it is not suitable for direct application in zinc–air batteries. , Although there are many studies on the performance optimization of gel electrolytes in recent years, there are still serious challenges in integrating resilient gels into high-performance flexible energy storage electronic devices. , …”