Yang Fan, Zhang Yifei, Liu Jingjing, Yousaf Muhammad, Yang Xinlei
Jiangsu Provincial Key Laboratory of Solar Energy Science and Technology, School of Energy & Environment, Southeast University, Nanjing 210096, China.
Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy & Environment, Southeast University, Nanjing 210096, China.
Nanomaterials (Basel). 2021 Jul 26;11(8):1923. doi: 10.3390/nano11081923.
As the stress-strain curve of standardized metal samples provides the basic details about mechanical properties of structural materials, the polarization curve or current-voltage characteristics of fuel cells are vitally important to explore the scientific mechanism of various solid oxide cells aiming at low operational temperatures (below 600 °C), ranging from protonic conductor ceramic cells (PCFC) to emerging Semiconductor ionic fuel cell (SIFC)/Semiconductor membrane fuel cells (SMFC). Thus far, worldwide efforts to achieve higher nominal peak power density (PPD) at a low operational temperature of over 0.1 s/cm ionic conductivity of electrolyte and super catalyst electrode is the key challenge for SIFCs. Thus, we illustrate an alternative approach to the present PPD concept and current-voltage characteristic. Case studies reveal that the holy grail of 1 W/cm from journal publications is expected to be reconsidered and normalized, since partial cells may still remain in a transient state (TS) to some extent, which means that they are unable to fulfill the prerequisite of a steady state (SS) characteristic of polarization curve measurement. Depending on the testing parameters, the reported PPD value can arbitrarily exist between higher transient power density (TPD) and lower stable power density (SPD). Herein, a standardized procedure has been proposed by modifying a quasi-steady state (QSS) characterization based on stabilized cell and time-prolonged measurements of common - plots. The present study indicates, when compared with steady state value, that QSS power density itself still provides a better approximation for the real performance of fuel cells, and concurrently recalls a novel paradigm transformation from a transient to steady state perspective in the oxide solid fuel cell community.
由于标准化金属样品的应力-应变曲线提供了结构材料力学性能的基本细节，因此燃料电池的极化曲线或电流-电压特性对于探索各种旨在低温（低于600°C）运行的固体氧化物电池的科学机制至关重要，这些电池包括质子导体陶瓷电池（PCFC）到新兴的半导体离子燃料电池（SIFC）/半导体膜燃料电池（SMFC）。到目前为止，在低温下实现高于0.1 s/cm的离子电导率和超级催化电极的更高标称峰值功率密度（PPD）是SIFC面临的关键挑战。因此，我们阐述了一种不同于当前PPD概念和电流-电压特性的替代方法。案例研究表明，期刊出版物中1 W/cm的圣杯有望被重新考虑和标准化，因为部分电池在某种程度上可能仍处于瞬态（TS），这意味着它们无法满足极化曲线测量稳态（SS）特性的先决条件。根据测试参数，报告的PPD值可能任意存在于较高的瞬态功率密度（TPD）和较低的稳定功率密度（SPD）之间。在此，通过修改基于稳定电池和常见曲线的时间延长测量的准稳态（QSS）表征，提出了一种标准化程序。本研究表明，与稳态值相比，QSS功率密度本身仍然为燃料电池的实际性能提供了更好的近似，同时在氧化物固体燃料电池领域唤起了从瞬态到稳态视角的新范式转变。
