元素替代在AB5型储氢合金中应用的研究进展

简要回顾了AB5型储氢合金的发展历程,综述了元素替代对AB5型储氢合金相结构与储氢性能的影响,总结了各种元素进行替代的研究进展。就目前的研究现状指出了元素替代在AB5型储氢合金应用中存在的问题以及今后的发展方向。     

电流密度和运行温度对PEM水电解制氢能耗的影响

质子交换膜(PEM)水电解制氢技术是采用绿电制取绿氢的重要方法,对我国实现双碳目标具有重要意义。优化运行参数是降低PEM水电解制氢系统能耗的一种重要途径。建立一套工业级PEM水电解制氢实验装置,通过现场实验,考察电流密度和运行温度对PEM水电解制氢系统能耗的影响,探讨优化运行参数降低运行能耗的方法。结果表明,当电流密度为0.2～1.4 A/cm²、运行温度为20～60℃,PEM水电解制氢系统单位能耗分别与电流密度、运行温度负相关。提高运行温度会引起电解电压下降,系统单位直流能耗显著降低。提高电流密度会造成系统单位直流能耗升高,而单位交流能耗降低。     

Phase structure and electrochemical properties of non-stoichiometric La0.7Ce0.3(Ni3.65Cu0.75Mn0.35Al0.15(Fe0.43B0.57)0.10)x hydrogen storage alloys

Phase structure and electrochemical characteristics of Co-free La0.7Ce0.3(Ni3.65Cu0.75Mn0.35Al0.15(Fe0.43B0.57)0.10)x (0.90≤x≤1.10) al-loys were investigated. When x was 0.90, the alloy was composed of LaNi5, La3Ni13B2 and Ce2Ni7 phases. The Ce2Ni7 phase disappeared, and the abundant of La3Ni13B2 phase decreased when x increased to 0.95. When x was 1.00 or higher the alloys consisted of LaNi5 phase. The lat-tice parameter a and the cell volume V of the LaNi5 phase decreased, and the c/a ratio of the LaNi5 phase increased with x value increasing. Maximum discharge capacity of the alloy electrodes first increased and then decreased with x value increasing from 0.90 to 1.10, and the highest value was obtained when x was 1.00. High-rate dischargeability at the discharge current density of 1200 mA/g increased from 50.7% (x= 0.90) to 64.1% (x=1.10). Both the charge-transfer reaction at the electrode/electrolyte interface and the hydrogen diffusion in the alloy were responsible for the high-rate dischargeability. Cycling capacity retention rate at 100th cycle (S100) gradually increased from 77.3% (x= 0.90) to 84.6% (x=1.10), which resulted from the increase in Ni content and the c/a ratio of the LaNi5 phase with x value increasing.     

Microstructure and electrochemical characteristics of La0.7Ce0.3Ni3.75Mn0.35Al0.15Cu0.75-x（V0.81Fe0.19）x hydrogen storage alloys

Microstructure and electrochemical characteristics of La0.7Ce0.3Ni3.75Mn0.35Al0.15Cu0.75-x(V0.81Fe0.19)x hydrogen storage alloys were investigated. XRD indicated that La0.7Ce0.3Ni3.75Mn0.35Al0.15Cu0.75-x(V0.81Fe0.19)x alloys consisted of a single phase with CaCu5-type structure, and the lattice parameter a and cell volume V increased with increasing x value. The maximum discharge capacity first increased from 319.0 (x=0) to 324.0 mAh/g (x=0.05), and then decreased to 307.0 mAh/g (x=0.20). The high-rate dischargeability at the discharge current density of 1200 mA/g first increased from 52.1% (x=0) to 59.1% (x=0.15), and then decreased to 55.4% (x=0.20). The hydrogen diffusion in the bulky alloy was responsible for the high-rate dischargeability. Cycling stability first increased with increasing x from 0 to 0.10 and then decreased when x increased to 0.20, which was resulted from the synthesized effect of the improvement of the pulverization resistance and the decrease of corrosion resistance.     

储氢合金表面处理的研究进展

系统介绍了近年国内外储氢合金表面处理工艺的研究进展,并讨论了各种处理工艺对储氢合金电化学容量、电催化活性、循环稳定性、高倍率放电能力、活化以及自放电等各个方面性能的影响。     

Effect of WFe substitution on microstructures and electrochemical hydrogen storage properties of LaNi3.70Co0.2-xMn0.30Al0.15Cu0.65(W0.42Fe0.58)x alloys

W0.42Fe0.58 alloy, instead of pure W and Fe, was used to substitute Co in LaNi3.70Co0.2Mn0.30Al0.15Cu0.65 alloy to improve the overall electrochemical properties with the decrement of the cost. Microst...     

热处理对La_(0.53)Ce_(0.47)Ni_(3.4)Co_(0.6)Mn_(0.3)Cu_(0.1)合金相结构和储氢性能的影响

采用感应熔炼法制备La_(0.53)Ce_(0.47)Ni_(3.4)Co_(0.6)Mn_(0.3)Cu_(0.1)储氢合金,并在不同温度下进行热处理,通过XRD对其相组成及结构进行表征,并采用双电极模拟电池测试系统对其储氢性能进行测试与分析。结果表明,随着退火温度的升高,合金的相组成未发生变化,但其晶化程度逐渐增高,晶体缺陷和晶格应力逐渐减少。热处理改善了合金的循环稳定性,提高了合金的电化学容量,但恶化了高倍率放电能力。     

稀土系储氢合金和镍氢电池产业现状及标准化体系建设研究

为了使稀土资源得到合理而充分地利用,对中国国内部分储氢合金和镍氢电池的生产企业进行了调研,了解了稀土系储氢合金和镍氢电池的产业化情况、产能情况以及市场现状和发展趋势等,并对稀土系储氢合金和镍氢电池行业存在的问题进行了分析,针对性地提出了解决思路。同时,从标准化的角度明确了制约储氢合金和镍氢电池产业发展的障碍,提出了规范行业发展所需的标准体系框架,对整个储氢合金和镍氢电池产业链的健康、可持续发展具有重要意义。     

氢能技术现状及其在储能发电领域的应用

随着化石能源消耗速度的增加,能源危机日益加剧,环境污染和温室效应问题越来越突出。为了应对上述问题,风能、太阳能和水能等可再生能源在人类社会的能源体系中占比越来越高,但可再生能源普遍存在稳定性差、利用效率低等问题。氢能既是清洁低碳的新能源,又可作为储能介质,必将在未来的能源结构中发挥不可替代的作用。氢气的制取、储运和应用技术是保障未来氢能经济顺利到来的重要支撑,尤其氢储能发电技术是实现氢能与电能充分结合和优势互补的重要途径。阐述了氢能利用的技术现状和发展趋势,对比分析了氢储能与其他形式储能的不同,最后明确了氢储能发电对未来电网安全及提高能源利用效率的重要意义。