This paper investigates the electrochemical performance of Li_xNa_1-xNi_0.8Al_0.2 (x=0.1, 0.2, 0.3, 0.4, LNNA) with different ratios of Na doping as electrode materials for ceramic fuel cells. It is found that the maximum power density (MPD) of the ceramic fuel cells prepared by co-pressure method with LNNA as symmetrical electrodes and GDC as electrolyte gradually decreases with the increase of Na doping in LNNA in H₂ at 550 ^oC. The MPD for the cell with LNNA-91 electrode reaches 718 mW·cm^-2, while that of the cell with LNNA-64 electrode is 503 mW·cm^-2. However, this MPD values still have strong competitiveness in the fuel cells operating at temperature around 550 ^oC. It was found that the LNNA anode is reduced by H₂, generating LiOH/NaOH molten salts, which diffuse into the GDC electrolyte and form a "GDC-Li/Na compounds" composite electrolyte with exceptional ionic conductivity. This is the key factor contributing to the excellent electrochemical performance of these ceramic fuel cells. The increase of Na content in LNNA will destroy its phase structure and generate new phases such as NaCO₃, resulting in the degradation of the electrode performance.Therefore, the doping amount of Na in LNNA needs to balance the cost and performance of the cell.

中文翻译：

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Li1-xNaxNi0.8Al0.2O2 作为低温陶瓷燃料电池对称电极的电化学性能


本文研究了不同 Na 掺杂比例下 Li_xNa_1-xNi_0.8Al_0.2 （x=0.1， 0.2， 0.3， 0.4， LNNA） 作为陶瓷燃料电池电极材料的电化学性能。研究发现，在 550 ^oC 时，以 LNNA 为对称电极，GDC 为电解质，随着 LNNA 中 Na 掺杂的增加，在 H₂ 中以 LNNA 为对称电极制备的陶瓷燃料电池的最大功率密度 （MPD） 逐渐降低。采用 LNNA-91 电极的电池的 MPD 达到 718mW·^cm-2，而采用 LNNA-64 电极的电池的 MPD 为 503mW·^cm-2。然而，这个 MPD 值在温度约为 550^oC 的燃料电池中仍然具有很强的竞争力。研究发现，LNNA 阳极被 H₂ 还原，生成 LiOH/NaOH 熔盐，这些盐扩散到 GDC 电解质中，形成具有优异离子电导率的“GDC-Li/Na 化合物”复合电解质。这是促成这些陶瓷燃料电池具有优异电化学性能的关键因素。LNNA 中 Na 含量的增加会破坏其相结构并产生 NaCO₃ 等新相，导致电极性能下降。因此，LNNA 中 Na 的掺杂量需要平衡电池的成本和性能。