Hydrocarbon-based membranes cost-effectively manage species transport and increase performance in thermally regenerative batteries

Nicholas R. Cross, Holkan Vazquez-Sanchez, Matthew J. Rau, Serguei N. Lvov, Michael A. Hickner, Christopher A. Gorski, Shashank S. Nagaraja, S. Mani Sarathy, Bruce E. Logan, Derek M. Hall

Research output: Contribution to journalArticlepeer-review

2 Scopus citations

Abstract

Low-temperature heat (T<130°C) can be utilized by thermally regenerative batteries (TRBs) for power production, allowing the thermal energy to be converted to storable chemical potential energy. However, TRBs suffer from high ohmic losses and ammonia crossover, which has slowed their development. In this study, we examined how the use of six different membranes influenced TRB performance, determined the most influential membrane parameters, and identified promising membrane candidates that cost-effectively increase TRB performance. Of the six membranes examined, an inexpensive, hydrocarbon CEM (Selemion CMVN) had low ammonia crossover without compromising resistance, resulting in good performance across all metrics studied. A thin anion exchange membrane (Sustainion, 50 microns) showed a high peak power density of 82 mW cm−2 due to low resistance, but the average power density and energy density were low due to high ammonia flux. Full discharge curves using Selemion CMVN provided an average power density of 26 ± 7 mW cm−2 with an energy density of 2.9 Wh L−1, which were large improvements on previous TRBs. A techno-economic analysis showed that Selemion CMVN had the lowest levelized cost of storage ($410 per MWh) at an applied current density of 50 mA cm−2.

Original languageEnglish (US)
Article number143090
JournalElectrochimica Acta
Volume467
DOIs
StatePublished - Nov 1 2023

All Science Journal Classification (ASJC) codes

  • General Chemical Engineering
  • Electrochemistry

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