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DOE OSTI · 2587732

Dual-Functional Thermocapacitive Heat Pump with Electrochemical Supercapacitors for Building Thermal Management and Energy Storage

James, Nelson [National Renewable Energy Lab., Golden, CO (United States)] (ORCID:0000000235475730)·Kim, Junyoung [National Renewable Energy Lab., Golden, CO (United States)]·Ozdogru, Bertan [National Renewable Energy Lab., Golden, CO (United States)]·Finegan, Donal [National Renewable Energy Lab., Golden, CO (United States)] (ORCID:000000034633560X)
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Abstract

Efficient heating and cooling technologies can help reduce the energy consumption and carbon emissions of buildings. This work explores the use of supercapacitive cells in a multifunctional, liquid-regenerated thermocapacitive heat pump that can provide electrical energy storage in addition to heating and cooling. A proof-of-concept prototype based on eight commercial supercapacitors and using deionized water as a liquid regenerator demonstrated cooling and energy storage capabilities. A peak cooling coefficient of performance (COPc) of 0.27 was achieved at a temperature drop of 0.24 K. The highest measured electrical energy storage density of the cells was 5.93 J cm-3, and the highest cooling power delivered relative to the volume of the cells was 0.58 mW cm-3. This work demonstrates the use of electrochemical energy storage devices in multifunctional equipment for thermal management in buildings.

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25 ENERGY STORAGEelectrochemical heat pumpenergy storageliquid regeneratedmultifunctionalsupercapacitors

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James, Nelson [National Renewable Energy Lab., Golden, CO (United States)] (ORCID:0000000235475730), Kim, Junyoung [National Renewable Energy Lab., Golden, CO (United States)], Ozdogru, Bertan [National Renewable Energy Lab., Golden, CO (United States)], Finegan, Donal [National Renewable Energy Lab., Golden, CO (United States)] (ORCID:000000034633560X). 2025-08-21. Dual-Functional Thermocapacitive Heat Pump with Electrochemical Supercapacitors for Building Thermal Management and Energy Storage. https://doi.org/10.1016/j.device.2025.100895

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