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Highly durable, coking and sulfur tolerant, fuel-flexible protonic ceramic fuel cells

Naturevolume 557pages217222 (2018) | Download Citation



Protonic ceramic fuel cells, like their higher-temperature solid-oxide fuel cell counterparts, can directly use both hydrogen and hydrocarbon fuels to produce electricity at potentially more than 50 per cent efficiency1,2. Most previous direct-hydrocarbon fuel cell research has focused on solid-oxide fuel cells based on oxygen-ion-conducting electrolytes, but carbon deposition (coking) and sulfur poisoning typically occur when such fuel cells are directly operated on hydrocarbon- and/or sulfur-containing fuels, resulting in severe performance degradation over time3,4,5,6. Despite studies suggesting good performance and anti-coking resistance in hydrocarbon-fuelled protonic ceramic fuel cells2,7,8, there have been no systematic studies of long-term durability. Here we present results from long-term testing of protonic ceramic fuel cells using a total of 11 different fuels (hydrogen, methane, domestic natural gas (with and without hydrogen sulfide), propane, n-butane, i-butane, iso-octane, methanol, ethanol and ammonia) at temperatures between 500 and 600 degrees Celsius. Several cells have been tested for over 6,000 hours, and we demonstrate excellent performance and exceptional durability (less than 1.5 per cent degradation per 1,000 hours in most cases) across all fuels without any modifications in the cell composition or architecture. Large fluctuations in temperature are tolerated, and coking is not observed even after thousands of hours of continuous operation. Finally, sulfur, a notorious poison for both low-temperature and high-temperature fuel cells, does not seem to affect the performance of protonic ceramic fuel cells when supplied at levels consistent with commercial fuels. The fuel flexibility and long-term durability demonstrated by the protonic ceramic fuel cell devices highlight the promise of this technology and its potential for commercial application.

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  1. 1.

    O’Hayre, R., Cha, S.-W., Whitney, C. & Prinz, F. B. Fuel Cell Fundamentals (Wiley, New York, 2009).

  2. 2.

    Duan, C. et al. Readily processed protonic ceramic fuel cells with high performance at low temperatures. Science 349, 1321–1326 (2015).

  3. 3.

    Park, S., Vohs, J. M. & Gorte, R. J. Direct oxidation of hydrocarbons in a solid-oxide fuel cell. Nature 404, 265–267 (2000).

  4. 4.

    Smith, T. R., Wood, A. & Birss, V. I. Effect of hydrogen sulfide on the direct internal reforming of methane in solid oxide fuel cells. Appl. Catal. A 354, 1–7 (2009).

  5. 5.

    Blinn, K. S. et al. Raman spectroscopic monitoring of carbon deposition on hydrocarbon-fed solid oxide fuel cell anodes. Energy Environ. Sci. 5, 7913–7917 (2012).

  6. 6.

    Atkinson, A. et al. Advanced anodes for high-temperature fuel cells. Nat. Mater. 3, 17–27 (2004).

  7. 7.

    Yang, L. et al. Enhanced sulfur and coking tolerance of a mixed ion conductor for SOFCs: BaZr0.1Ce0.7Y0.2−xYbxO3−δ. Science 326, 126–129 (2009).

  8. 8.

    Hua, B. et al. Novel layered solid oxide fuel cells with multiple-twinned Ni0.8Co0.2 nanoparticles: the key to thermally independent CO2 utilization and power-chemical cogeneration. Energy Environ. Sci. 9, 207–215 (2016).

  9. 9.

    Schädel, B. T., Duisberg, M. & Deutschmann, O. Steam reforming of methane, ethane, propane, butane, and natural gas over a rhodium-based catalyst. Catal. Today 142, 42–51 (2009).

  10. 10.

    Vaidya, P. D. & Rodrigues, A. E. Insight into steam reforming of ethanol to produce hydrogen for fuel cells. Chem. Eng. J. 117, 39–49 (2006).

  11. 11.

    García, E. Y. & Laborde, M. A. Hydrogen production by the steam reforming of ethanol: thermodynamic analysis. Int. J. Hydrogen Energy 16, 307–312 (1991).

  12. 12.

    Sasaki, K. & Teraoka, Y. Equilibria in fuel cell gases. J. Electrochem. Soc. 150, A885–A888 (2003).

  13. 13.

    Borglum, B. P. & Ghezel-Ayagh, H. Development of solid oxide fuel cells at Versa Power Systems and FuelCell Energy. ECS Trans. 68, 89–94 (2015).

  14. 14.

    Albrecht, K. J., Duan, C., O’Hayre, R. & Braun, R. J. Modeling intermediate temperature protonic ceramic fuel cells. ECS Trans. 68, 3165–3175 (2015).

  15. 15.

    Zhu, H. & Kee, R. J. A general mathematical model for analyzing the performance of fuel-cell membrane-electrode assemblies. J. Power Sources 117, 61–74 (2003).

  16. 16.

    Zhu, H. & Kee, R. J. Membrane polarization in mixed-conducting ceramic fuel cells and electrolyzers. Int. J. Hydrogen Energy 41, 2931–2943 (2016).

  17. 17.

    Li, M. et al. Enhancing sulfur tolerance of Ni-based cermet anodes of solid oxide fuel cells by ytterbium-doped barium cerate infiltration. ACS Appl. Mater. Interfaces 8, (10293–10301 (2016).

  18. 18.

    Neagu, D. et al. Nano-socketed nickel particles with enhanced coking resistance grown in situ by redox exsolution. Nat. Commun. 6, 8120 (2015).

  19. 19.

    Bandura, A. V., Evarestov, R. A. & Kuruch, D. D. Hybrid HF–DFT modeling of monolayer water adsorption on (001) surface of cubic BaHfO3 and BaZrO3 crystals. Surf. Sci. 604, 1591–1597 (2010).

  20. 20.

    Liu, M. et al. Direct octane fuel cells: a promising power for transportation. Nano Energy 1, 448–455 (2012).

  21. 21.

    Li, X. et al. In situ probing of the mechanisms of coking resistance on catalyst-modified anodes for solid oxide fuel cells. Chem. Mater. 27, 822–828 (2015).

  22. 22.

    Karakaya, C., Otterstätter, R., Maier, L. & Deutschmann, O. Kinetics of the water–gas shift reaction over Rh/Al2O3 catalysts. Appl. Catal. A 470, 31–44 (2014).

  23. 23.

    Catapan, R. C., Oliveira, A. A. M., Chen, Y. & Vlachos, D. G. DFT study of the water–gas shift reaction and coke formation on Ni(111) and Ni(211) surfaces. J. Phys. Chem. C 116, 20281–20291 (2012).

  24. 24.

    Yang, L. et al. Promotion of water-mediated carbon removal by nanostructured barium oxide/nickel interfaces in solid oxide fuel cells. Nat. Commun. 2, 357 (2011).

  25. 25.

    Sasaki, K. et al. H2S poisoning of solid oxide fuel cells. J. Electrochem. Soc. 153, A2023–A2029 (2006).

  26. 26.

    Rostrup-Nielsen, J. R., Sehested, J. & Nørskov, J. K. in Advances in Catalysis Vol. 47, 65–139 (2002).

  27. 27.

    Rostrup-Nielsen, J. & Christiansen, L. J. Concepts in Syngas Manufacture (Imperial College Press, London, 2011).

  28. 28.

    Fabbri, E., Magrasó, A. & Pergolesi, D. Low-temperature solid-oxide fuel cells based on proton-conducting electrolytes. MRS Bull. 39, 792–797 (2014).

  29. 29.

    Lai, W. & Haile, S. M. Electrochemical impedance spectroscopy of mixed conductors under a chemical potential gradient: a case study of Pt|SDC|BSCF. Phys. Chem. Chem. Phys. 10, 865–883 (2008).

  30. 30.

    Kee, R. J. et al. Modeling the steady-state and transient response of polarized and non-polarized proton-conducting doped-perovskite membranes. J. Electrochem. Soc. 160, F290–F300 (2013).

  31. 31.

    Shishkin, M. & Ziegler, T. Coke-tolerant Ni/BaCe1–xY x O3−δ anodes for solid oxide fuel cells: DFT + U study. J. Phys. Chem. C 117, 7086–7096 (2013).

  32. 32.

    Pajonk, G. Contribution of spillover effects to heterogeneous catalysis. Appl. Catal. A Gen. 202, 157–169 (2000).

  33. 33.

    Grass, M. E. et al. New ambient pressure photoemission endstation at Advanced Light Source beamline 9.3.2. Rev. Sci. Instrum. 81, 053106 (2010).

  34. 34.

    Crumlin, E. J. et al. Surface strontium enrichment on highly active perovskites for oxygen electrocatalysis in solid oxide fuel cells. Energy Environ. Sci. 5, 6081 (2012).

  35. 35.

    Bartholomew, C. H. Mechanisms of catalyst deactivation. Appl. Catal. A Gen. 212, 17–60 (2001).

  36. 36.

    Tong, J. et al. Solid-state reactive sintering mechanism for large-grained yttrium-doped barium zirconate proton conducting ceramics. J. Mater. Chem. 20, 6333 (2010).

  37. 37.

    Sengodan, S. et al. Layered oxygen-deficient double perovskite as an efficient and stable anode for direct hydrocarbon solid oxide fuel cells. Nat. Mater. 14, 205–209 (2015).

  38. 38.

    Yang, C. et al. In situ fabrication of CoFe alloy nanoparticles structured (Pr0.4Sr0.6)3(Fe0.85Nb0.15)2O7 ceramic anode for direct hydrocarbon solid oxide fuel cells. Nano Energy 11, 704–710 (2015).

  39. 39.

    Tamm, K., Küngas, R., Gorte, R. J. & Lust, E. Solid oxide fuel cell anodes prepared by infiltration of strontium doped lanthanum vanadate into doped ceria electrolyte. Electrochim. Acta 106, 398–405 (2013).

  40. 40.

    Yoon, D. et al. Hydrocarbon-fueled solid oxide fuel cells with surface-modified, hydroxylated Sn/Ni–Ce0.8Gd0.2O1.9 heterogeneous catalyst anode. J. Mater. Chem. A 2, 17041–17046 (2014).

  41. 41.

    Chen, Y. et al. Direct-methane solid oxide fuel cells with hierarchically porous Ni-based anode deposited with nanocatalyst layer. Nano Energy 10, 1–9 (2014).

  42. 42.

    Tao, Z., Hou, G., Xu, N. & Zhang, Q. A highly coking-resistant solid oxide fuel cell with a nickel doped ceria: Ce1−xNi x O2−y reformation layer. Int. J. Hydrogen Energy 39, 5113–5120 (2014).

  43. 43.

    Zhan, Z. & Barnett, S. A. An octane-fueled solid oxide fuel cell. Science 308, 844–847 (2005).

  44. 44.

    Huang, Y.-H. Double perovskites as anode materials for solid-oxide fuel cells. Science 312, 254–257 (2006).

  45. 45.

    Choi, S. et al. A robust symmetrical electrode with layered perovskite structure for direct hydrocarbon solid oxide fuel cells: PrBa0.8Ca0.2Mn2O5+δ. J. Mater. Chem. A 4, 1747–1753 (2016).

  46. 46.

    Shin, T. H., Hagiwara, H., Ida, S. & Ishihara, T. RuO2 nanoparticle-modified (Ce,Mn,Fe)O2/(La,Sr) (Fe,Mn)O3 composite oxide as an active anode for direct hydrocarbon type solid oxide fuel cells. J. Power Sources 289, 138–145 (2015).

  47. 47.

    Wu, X. et al. Preparation and electrochemical performance of silver impregnated Ni-YSZ anode for solid oxide fuel cell in dry methane. Int. J. Hydrogen Energy 40, 16484–16493 (2015).

  48. 48.

    Liu, S., Chuang, K. T. & Luo, J.-L. Double-layered perovskite anode with in situ exsolution of a Co–Fe alloy to cogenerate ethylene and electricity in a proton-conducting ethane fuel cell. ACS Catal. 6, 760–768 (2016).

  49. 49.

    Kaur, G. & Basu, S. Physical characterization and electrochemical performance of copper-iron-ceria-YSZ anode-based SOFCs in H2 and methane fuels. Int. J. Energy Res. 39, 1345–1354 (2015).

  50. 50.

    Sun, Y.-F. et al. An ingenious Ni/Ce co-doped titanate based perovskite as a coking-tolerant anode material for direct hydrocarbon solid oxide fuel cells. J. Mater. Chem. A 3, 22830–22838, (2015); erratum: https://doi.org/10.1039/C6TA90257J

  51. 51.

    Porter, D. L. & Heuer, A. H. Microstructural development in MgO-partially stabilized zirconia (Mg-PSZ). J. Am. Ceram. Soc. 62, 298–305 (1979).

  52. 52.

    Hua, B., Li, M., Chi, B. & Jian, L. Enhanced electrochemical performance and carbon deposition resistance of Ni-YSZ anode of solid oxide fuel cells by in situ formed Ni–MnO layer for CH4 on-cell reforming. J. Mater. Chem. A 2, 1150–1158 (2014).

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This work was supported by Advanced Research Projects Agency–Energy (ARPA-E) for funding under the REBELS program (award DE-AR0000493). Additional support was provided by the Army Research Office under grant no. W911NF-17-1-0051 and the Colorado Office of Economic Development and International Trade (COEDIT) under their Advanced Industries Proof-of-Concept grant program. The views and conclusions contained in this document are those of the authors and should not be interpreted as representing the official policies, either expressed or implied, of ARPA-E, the Department of Energy, the Army Research Office or the US Government. This research used resources of the Advanced Light Source, which is a DOE Office of Science User Facility under contract no. DE-AC02-05CH11231. The US Government is authorized to reproduce and distribute reprints for Government purposes notwithstanding any copyright notation herein.

Reviewer information

Nature thanks J. Dailly, T. Norby, Z. Shao and the other anonymous reviewer(s) for their contribution to the peer review of this work.

Author information


  1. Colorado School of Mines, Golden, CO, USA

    • Chuancheng Duan
    • , Robert J. Kee
    • , Huayang Zhu
    • , Canan Karakaya
    • , Yachao Chen
    • , Sandrine Ricote
    • , Robert Braun
    • , Neal P. Sullivan
    •  & Ryan O’Hayre
  2. Department of Materials Science and Engineering, University of Maryland, College Park, MD, USA

    • Angelique Jarry
  3. Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA, USA

    • Ethan J. Crumlin
  4. CoorsTek, Golden, CO, USA

    • David Hook


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C.D. and R.O’H. developed the intellectual concept, designed the fuel cell experiments, analysed the data and led the manuscript writing. N.P.S. and R.B. provided supervisory guidance on the fuel cell experiments, data interpretation, and manuscript refinement. Y.C. and C.D. conducted the in situ HT-Raman experiments. S.R., A.J. and E.J.C. designed, executed and analysed the Advanced Light Source ambient pressure X-ray photoelectron spectroscopy studies. D.H. performed the high-temperature X-ray diffraction experiments to study the phase formation of BaY2NiO5. C.K., H.Z. and R.J.K. developed the PCFC versus SOFC anode mass balance and Nernst potential model comparison and contributed to the discussion and analysis of the bi-functional anti-coking and sulfur-resistant mechanism hypotheses ascribed to the Ni/BZY anode.

Competing interests

The authors declare no competing interests.

Corresponding authors

Correspondence to Chuancheng Duan or Ryan O’Hayre.

Extended data figures and tables

  1. Extended Data Fig. 1 Performance of PCFCs under 10 fuels.

    a, jV and j–P curves of PCFC under hydrogen (flow rate of hydrogen: 15 ml min−1, cell 1). b, jV and j–P curves of direct-methanol PCFC at 600–350 °C. Flow rate of the mixture of methanol and water (molar ratio of water/ethanol is 1, cell 3) is 0.024 ml min−1. c, jV and j–P curves of PCFC under 10 vol% iso-C4H 10 + 20 vol% O2 + 70 vol% H2O (flow rate of iso-C4H10: 0.9 ml min−1, cell 4). d, jV and j–P curves of PCFC under 10 vol% n-C4H10 + 20 vol% O2 + 70 vol% H2O (flow rate of n-C4H10: 0.9 ml min−1, cell 5). e, jV and j–P curves of PCFC under 20 vol% C3H8 + 20 vol% O2 + 60 vol% H2O (flow rate of C3H8: 1.6 ml min−1, cell 4). f, jV and j–P curves of PCFC under 33.3 vol% natural gas (simulated natural gas with 19.5 p.p.m. H2S, flow rate of natural gas: 5 ml min−1, cell 7) + 66.7 vol% H2O. g, jV and j–P curves of PCFC under 33.3 vol% natural gas (simulated natural gas without H2S, flow rate of natural gas: 5 ml min−1, cell 7) + 66.7 vol% H2O. h, jV and j–P curves of PCFC under 33.3 vol% methane (flow rate of methane: 5 ml min−1, cell 7) + 66.7 vol% H2O. i, jV and j–P curves of PCFC under 28.5 vol% methane (flow rate of methane: 5 ml min−1, cell 8) + 71.5 vol% H2O. j, jV and j–P curves of direct-ethanol PCFC at 600 °C and 550 °C. Flow rate of the mixture of ethanol and water (molar ratio of water/ethanol is 7, cell 10) is 0.005 ml min−1.

  2. Extended Data Fig. 2 Anode-side exhaust gas composition of PCFCs on propane and iso-butane.

    a, Direct-propane PCFC. b, Direct-iso-butane PCFC.

  3. Extended Data Fig. 3 SEM images of PCFC (Cell 4) after running for about 6,000 h on hydrocarbons at 500 °C.

    a, Anode (low magnification). b, Anode (high magnification). c, The sandwich structure of this cell after running for about 6,000 h. d, The interface between electrolyte and cathode. e, High magnification of cathode after 6,000 h operation. f, Raman spectrum of the PCFC anode after 6,000 h of operation on hydrocarbon fuel at 500 °C. A carbonate peak is visible at 1,060 cm−1 but the graphitic carbon (G band) and disordered carbon (D band), which would be present at 1,580 cm−1 and 1,350 cm−1, are not apparent, indicating the absence of graphitic carbon and disordered carbon deposits in the anode even after long-term operation on hydrocarbon fuel. Long-term stabilities of direct hydrocarbons PCFCs were tested at 500 °C. At this temperature, the structure type of carbon species should be polymeric, amorphous films or filaments (Cβ), vermicular filaments, fibres and/or whiskers (Cγ), or graphitic platelets or films (Cc)35. Typically, these carbon species are visible (by SEM) in SOFC anodes after running on hydrocarbon fuels, but the high-magnification SEM images of our PCFC anode (Extended Data Fig. 3a, b) show no visible evidence of such carbon structures. To further substantiate this conclusion, post-mortem Raman analyses show that there are no disordered and graphitic carbon species found in the PCFC anode even after long-term operation on hydrocarbon fuels (Extended Data Fig. 3f).

  4. Extended Data Fig. 4 TEM image and EDS mapping of PCFC (Cell 3) after 8,000 h operation on methanol.

    a, TEM image of lamella from BZY20 PCFC electrolyte/cathode interface prepared by FIB. bh, HAADF image of the electrolyte/cathode interface, and corresponding EDS maps of Ba, Zr, Y, Co, Fe and O. There is no chemical reaction between the electrolyte and electrolyte which indicates the excellent chemical compatibility of cathode with electrolyte. EDS mapping of cathode shows there is no obvious elemental segregation.

  5. Extended Data Fig. 5 Coking resistance of Ni/BZY and Ni/YSZ anodes investigated by in situ HT-Raman spectroscopy.

    a, Raman spectra of Ni/YSZ anode exposed to humidified methane (S:C = 2; 500 °C) at various times up to 200 min. b, Raman spectra of Ni/BZY anode exposed to humidified methane (S:C = 2; 500 °C) at various times up to 360 min. c, Raman spectra of Ni/BZY anode exposed to humidified methane (S:C = 1; 500 °C) at various times up to 72 h (4,320 min). d, Raman spectra of Ni/YSZ anode exposed to humidified methane (S:C ≈ 1; 550 °C) at various times up to 40 min. e, Raman spectra of Ni/BZY anode exposed to humidified methane (S:C ≈ 1; 550 °C) at various times up to 100 min.

  6. Extended Data Fig. 6 SEM image of the anode of a PCFC after running for 1,400 and 6,000 h on hydrocarbons at 500 °C.

    a, b, Operation for 6,000 h on iso-butane and propane (cell 4). c, Operation for 1,400 h on methane. d, Operation for 6,000 h on iso-butane and propane (cell 4). The Tamman temperature of nickel is 581 °C. The target operating temperature of our PCFCs is lower than 600 °C, and most of the long-term stability testing conducted in this study was at 500 °C (that is, well below the Tamman temperature), at which Ni sintering/coarsening is avoided. Indeed, as shown in Extended Data Fig. 6c, d, the distribution and size of Ni nanoparticles on the BZY anode support remain essentially constant between 1,400 and 6,000 h of operation.

  7. Extended Data Fig. 7 The mechanism of SSRS and exsolution of Ni nanoparticles.

    a, Exposure to reducing conditions (for example, H2 or hydrocarbon fuel) at typical PCFC operating temperatures triggers the in situ exsolution of Ni nanoparticles onto the surface of the BZY phase in the cermet anode. This exsolution process is driven by the decreased solubility of Ni in the BZY phase under anode operating conditions (500–600 °C, highly reducing) compared with the much higher starting solubility of Ni in the BZY phase under anode synthesis conditions (1,450 °C, highly oxidizing). In addition, fuel cell operation also drives the decomposition of a residual BaY2NiO5 phase which is a by-product of the solid-state reactive-sintering method (SSRS) used to synthesize the anode. As illustrated here, the SSRS process enables the anode to be rapidly and inexpensively fabricated in a single step starting from a homogeneous mixture of BaCO3, ZrO2, Y2O3, NiO and pore former, which is fired under oxidizing conditions at 1,450 °C for 18 h. During firing, a complex phase-formation and sintering process, involving the transient formation and decomposition of BaY2NiO5, leads to the creation of a porous two-phase NiO + Ni-doped BZY composite anode with a small amount of dispersed residual BaY2NiO5. During initial fuel cell operation, the NiO phase is reduced to Ni metal, while the Ni-doped BZY is reduced to BZY36, concomitant with the exsolution of Ni nanoparticles which we hypothesize enhance the performance and durability of the fuel cell. b, Amplified main peaks of XRD patterns of BZY20 phase after sintering in air with different NiO amount in precursors. The amount of Ni diffusing into the BZY is determined by the defect reaction equilibrium. The amplified main XRD peaks of BZY20 phase shift to the higher angles with increasing amounts of Ni in the anode. This is consistent with a decreasing lattice constant with increasing Ni substitution on the B-site of the BZY lattice owing to the smaller size of Ni2+ compared with Zr4+ or Y3+. c, XRD patterns of BZY20 anode after sintering in air and reduction in hydrogen at 600 °C for 150 h. d, Amplified main peaks of XRD patterns of BZY20 phase after sintering in air and reduction in hydrogen at 600 °C for 150 h. The peak shifts to smaller angles after reduction which is consistent with the exsolution of Ni from BZY lattice, leading to a concomitant increase in the lattice constant of the BZY phase. e, BaY2NiO5 phase formation temperature profile investigated by in situ high-temperature XRD. The colour indicates the intensity of the main peak of BaY2NiO5.

  8. Extended Data Fig. 8 SEM images of the Ni nanoparticle exsolution process in the PCFC anode.

    a, b, BZY20 phase of the anode before reduction. The surface of the BZY20 phase is very clean, and there are no nanoparticles along the grain boundaries or on the triple junction points. c, d, BZY20 phase of the anode after reduction under hydrogen at 600 °C for 50 h. Nickel nanoparticles begin to form on the triple junction points and grain boundaries. e, f, BZY20 phase of the anode after reduction under hydrogen at 600 °C for 100 h. More Ni nanoparticles begin to form along grain surfaces and boundaries. The size of exsolved Ni nanoparticles is less than 100 nm.

  9. Extended Data Fig. 9 Evolution of the AP-XPS elemental survey spectrum of Ni/BaZr0.9Y0.1O3-δ (BZY) and Ni/Zr0.92Y0.08O2−δ (8YSZ) patterned microelectrodes.

    a, Ni/BZY-based microelectrode, b, Ni/YSZ-based microelectrode.

  10. Extended Data Table 1 Performance comparison of SOFCs with PCFCs

Supplementary information

  1. Video 1: Direct flame protonic ceramic fuel cell

    This video shows a direct flame protonic ceramic fuel cell.

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