A High-Voltage Zn-Organic Battery Using a Nonflammable Organic Electrolyte

Area of Science:

• Electrochemistry
• Materials Science
• Energy Storage

Background:

• Aqueous zinc batteries face challenges with zinc corrosion and dendrite formation, limiting anode utilization and cathode mass-loading.
• Existing high-performance aqueous zinc batteries often exhibit low zinc utilization (<0.6%) and cathode mass-loading (<3 mg cm⁻²).

Purpose of the Study:

• To develop a novel organic electrolyte for aqueous zinc batteries that mitigates zinc corrosion and dendrite formation.
• To enhance the performance metrics of aqueous zinc batteries, including zinc utilization and cathode mass-loading.

Main Methods:

• Formulation of a new organic electrolyte using zinc trifluoromethanesulfonate (Zn-TFMS) salt in a mixed solvent of propylene carbonate (PC) and triethyl phosphate (TEP).
• Optimization of the PC/TEP solvent ratio to achieve desired electrolyte properties.
• Fabrication and testing of a 2V Zn//polytriphenylamine composite (PTPAn) battery using the optimized electrolyte.

Main Results:

• The optimized electrolyte exhibits high ionic conductivity and a wide stable potential window.
• The electrolyte facilitates dendrite-free zinc plating and stripping, enhancing battery safety and longevity.
• The TEP solvent component imparts nonflammability to the electrolyte.
• The fabricated Zn//PTPAn battery demonstrates high rate capability and a long cycle life (2400 cycles) with high PTPAn mass-loading (16 mg cm⁻²) and high Zn utilization (3.5%).

Conclusions:

• The developed organic electrolyte effectively addresses key limitations in aqueous zinc batteries, enabling significantly improved performance.
• This advancement paves the way for safer, more efficient, and higher-capacity aqueous zinc battery technologies.