Abstract:

To effectively address the low-temperature heat and CO₂ in industrial flue gas, a thermal regenerative battery stack coupled with an electrochemical reduction reaction of carbon dioxide system (TRB-CO₂RR) was developed. A stack was constructed by connecting several non-aqueous thermally regenerative batteries in series, serving to drive an electrochemical reduction of CO₂. The characteristics of CO₂RR, the performance of the non-aqueous TRB stack, and the coupling characteristics of the non-aqueous TRB-CO₂RR system were studied. The results demonstrated a relatively uniform distribution of catalyst on a carbon paper-supported silver nanoparticle porous electrode. The optimal CO₂RR_{performance was observed at a potential of -1.8V (corresponding to a slot voltage of 5.1V), with a CO Faraday efficiency reaching a peak of 78.7%. Therefore, a series stack of six batteries was constructed. The open circuit voltage reached approximately 7.2V, with a maximum power of 235mW and a relatively stable discharge lasting for 34min. In the non-aqueous TRB-CO2RR coupled system, no reverse pole phenomenon was observed in the stack, and the CO Faraday efficiency (73.1%) closely approached the optimum value achieved by a stable power supply. Further research could be focused on optimizing catalysts and stack design, aiming to improve the efficiency of CO2RR in this coupled system.}

Key words: thermally regenerative battery, electrochemical CO₂ reduction, series stack, power generation, stability, Faraday efficiency, electrochemistry, recovery

摘要：

为了减少工业烟气中余热与CO₂的排放，本文提出了热再生电池堆-二氧化碳电化学还原池系统（TRB-CO₂RR）。该系统通过串联多个非水系热再生电池（thermally regenerative battery，TRB）构建电堆，并将其用于驱动CO₂电化学还原（electrochemical reduction of CO₂，CO₂RR）。本文研究了CO₂电化学还原特性、非水系TRB电堆性能及非水系TRB-CO₂RR系统耦合特性。研究结果表明，碳纸负载纳米银多孔电极上催化剂分布较为均匀，在-1.8V电位下（对应的槽电压为5.1V）表现出最佳的电化学还原CO₂性能，其CO法拉第效率达到了最佳值78.7%。为此，构建了6个子电池的串联电堆，开路电压达到7.2V左右，最大功率为235mW，在34min内放电相对稳定。运行非水系TRB-CO₂RR耦合系统后，电堆未出现反极现象，CO法拉第效率（73.1%）接近稳定电源所获得的最佳值。未来研究可通过优化催化剂和电堆设计，有望进一步提高耦合系统CO₂RR转化效率。

关键词: 热再生电池, CO₂电化学还原, 串联电堆, 产电功率, 稳定性, 法拉第效率, 电化学, 回收