A Comprehensive Formulation of Aqueous Electrolytes for Low-Temperature Supercapacitors

Area of Science:

• Materials Science
• Electrochemistry
• Sustainable Energy

Background:

• Growing energy demands necessitate safer, sustainable energy storage solutions.
• Electrolyte design must consider toxicity, eco-compatibility, and cost for widespread adoption.
• Low-temperature performance is a critical challenge for current energy storage devices.

Purpose of the Study:

• To develop a non-toxic, cost-efficient ternary electrolyte for low-temperature applications.
• To investigate the performance of an electrochemical double-layer capacitor (EDLC) using the novel electrolyte.
• To assess the thermal and electrochemical stability of the EDLC at sub-zero temperatures.

Main Methods:

• Formulation of a eutectic system using LiNO3 in water with 1,3-propylene glycol.
• Fabrication and testing of an electrochemical double-layer capacitor (EDLC) with the developed electrolyte.
• Evaluation of device performance at -40°C, including operating voltage and floating stability.
• Assessment of capacitance temperature resilience at 20°C.

Main Results:

• The ternary electrolyte exhibited a wide liquid range and was effective at -40°C.
• The EDLC achieved an optimal operating voltage of 2.0 V at -40°C with over 100 hours of stable floating.
• The device demonstrated near-total capacitance temperature resilience when initially set up at 20°C.

Conclusions:

• The developed non-toxic, cost-efficient electrolyte shows significant promise for low-temperature energy storage.
• The EDLC utilizing this electrolyte exhibits favorable thermal and electrochemical behaviors, suitable for demanding applications.
• This research contributes to the development of safer and more sustainable energy storage solutions.