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Continuous electrochemical refrigeration based on the Brayton cycle


Zero-global-warming-potential cooling technologies can mitigate the climate change effects attributed to the use of conventional vapour compression refrigeration. In this work, we conceptualize an electrochemical refrigeration cycle and demonstrate a proof-of-concept prototype in continuous operation. The refrigerator is based on the Brayton cycle and draws inspiration from redox flow battery technologies. A peak coefficient of performance of 8.09 was measured with a small temperature drop of 0.07 K. A peak cooling load of 0.934 W with a coefficient of performance of 0.93 was measured, however, with only a modest measured temperature drop of 0.15 K. This is still much lower than the theoretical maximum temperature drop of 2–7 K for these electrolytes. This work could inspire research into high-cooling-capacity redox-active species, multi-fluid heat exchanger design and high-efficiency electrochemical refrigeration cell architectures.

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Fig. 1: Concept for the BECR.
Fig. 2: Electrolyte characterization.
Fig. 3: BECR proof of concept.
Fig. 4: BECR performance.
Fig. 5: Comparison of refrigeration technologies.

Data availability

The data that support the results of this study are provided as Supplementary Data. Source data are provided with this paper.


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A.R. was partially supported by the Office of Naval Research (award no. N00014-19-1-2162).

Author information

Authors and Affiliations



A.R. and S.K.Y. conceptualized the work. A.R. developed the methodology, performed the experiments, analysed the data and wrote the original draught. A.R., I.S.M. and S.K.Y. reviewed and edited the draught. S.K.Y. supervised the research and acquired funding.

Corresponding author

Correspondence to Shannon K. Yee.

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Competing interests

A.R. and S.K.Y. are inventors on a US patent (application no. 63/172,925, patent pending) detailing the architecture, chemistry and operation of the BECR. I.S.M. declares no competing interests.

Peer review

Peer review information

Nature Energy thanks Shien-Ping Feng, Neil Mathur, Nini Pryds and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

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Supplementary information

Supplementary Information

Supplementary Notes 1 and 2, Figs. 1–17 and Tables 1–4.

Supplementary Data

Supplementary data file for Fig. 16.

Source data

Source Data Fig. 3

Source data for Fig. 3.

Source Data Fig. 4

Source data for Fig. 4.

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Rajan, A., McKay, I.S. & Yee, S.K. Continuous electrochemical refrigeration based on the Brayton cycle. Nat Energy 7, 320–328 (2022).

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