Low-operating temperature quasi-solid-state potassium-ion battery based on commercial materials.

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Quasi-solid-state potassium-ion batteries (QSPIBs) offer enhanced safety for energy storage.
• Development of stable and conductive electrolyte membranes is crucial for QSPIB performance.

Purpose of the Study:

• To present a facile, large-scale method for preparing a potassium-ion composite electrolyte membrane.
• To evaluate the electrochemical performance of QSPIBs utilizing the novel membrane.

Main Methods:

• Synthesis of a potassium-ion composite electrolyte membrane.
• Fabrication and electrochemical testing of half and full QSPIBs using commercial electrodes.
• Systematic study of the reaction mechanism and structure evolution of a 3,4,9,10-perylene-tetracarboxylicacid-dianhydride (PTCDA) cathode.

Main Results:

• The synthesized membrane exhibits high ionic conductivity (9.31 × 10⁻⁵ S cm⁻¹ at 25 °C), excellent electrochemical stability, and good mechanical flexibility.
• QSPIBs demonstrated superior low-temperature performance (e.g., 90.7 mAh g⁻¹ at -15 °C for full cells) and promising rate capability (e.g., 90.9 mAh g⁻¹ at 800 mA g⁻¹ for full cells).
• Insights into the cathode's reaction mechanism and structural changes were obtained.

Conclusions:

• The developed low-cost composite electrolyte membrane facilitates the creation of safer and more durable QSPIBs.
• The findings open avenues for practical applications of QSPIBs in the electronics industry, particularly in demanding conditions.
• This work advances the development of advanced potassium-ion battery technology.