CuSO₄/[Cu(NH₃)₄]SO₄-Composite Thermochemical Energy Storage Materials

Area of Science:

• Materials Science
• Chemical Engineering
• Energy Storage

Background:

• Thermochemical energy storage offers high energy density and long-term storage capabilities.
• The copper sulfate ([Cu(NH₃)₄]SO₄) system exhibits excellent reversibility and operates below 350 °C.
• Significant material expansion during ammonia uptake poses challenges for pure CuSO₄.

Purpose of the Study:

• To develop composite materials for improved thermochemical energy storage.
• To mitigate volume expansion and enhance thermal conductivity of CuSO₄-based materials.
• To characterize composite performance regarding energy storage density and reversibility.

Main Methods:

• Preparation of anhydrous CuSO₄ composites with inert inorganic support materials.
• Characterization of energy storage density, reaction reversibility, and thermal conductivity.
• Analysis of particle morphology and bulk volume changes.

Main Results:

• A 10:1 CuSO₄-sepiolite composite demonstrated superior thermochemical energy storage properties.
• The composite exhibited attractive energy storage density and slightly improved thermal conductivity.
• Reduced bulk volume work was observed in the composite compared to pure CuSO₄.

Conclusions:

• CuSO₄-sepiolite composites represent a promising advancement in thermochemical energy storage materials.
• Optimized composites can overcome limitations of pure salts, enhancing practical applicability.
• This approach facilitates efficient medium-temperature heat storage and release.