鈉超離子導體型固態電解質之鋰二氧化碳電池

Abstract

電池為現今科技重要之儲能系統，鋰電池即為目前最普遍之儲能產物，然其液態電解質存在漏液、爆炸等安全問題，故為解決上述問題，固態電池成為次世代電池之主要研究方向。此外，因應全球溫室效應產生二氧化碳氣體，故鋰二氧化碳電池之研發尤為重要。鋰二氧化碳電池之能量密度約為1876 Wh kg−1，優於目前市售鋰離子電池僅300 Wh kg−1之能量密度，此優勢顯示未來儲能之潛在應用前景。本研究乃使用鋰鋁鍺磷(Li1.6Al0.5Ge1.5(PO4)3; LAGP)作為固態電解質製作固態鋰二氧化碳電池，陰極使用釕奈米顆粒修飾之多壁奈米碳管(Ru@MWCNT)，並研究不同陰極觸媒對於電池性能之影響。Ru/CNTs陰極觸媒於固態鋰二氧化碳電池中扮演至關重要之作用。此陰極具大表面積、放電容量、優異之可逆性、長循環壽命與低過電位。因其活性位點增加，助於提升二氧化碳還原與析出反應之性能。Ru/CNTs陰極之固態鋰二氧化碳電池最大放電容量為4541 mAh g−1且電池壽命為45次循環，電位差為1.24 V。

The battery is an important energy storage system in today's technology. Lithium battery is the most common energy storage product. However, its liquid electrolyte has safety problems such as leakage and explosion. To solve these problems, solid-state batteries have become the main research for next-generation batteries. Moreover, because of CO2 gas in the global greenhouse effect, the research on Li–CO2 batteries is particularly important. The energy density of the Li–CO2 is about 1876 Wh kg−1, which is better than the energy density of the current commercially available Li-ion battery, which is only 300 Wh kg−1. This advantage shows the potential application of energy storage in the future.In this study, Li1.6Al0.5Ge1.5(PO4)3 (LAGP) is used as the solid electrolyte to fabricate a solid-state Li–CO2 battery and the cathode uses Ru nanoparticle-modified multi-wall carbon nanotubes (Ru@MWCNTs), then study the effect of different cathode catalysts on battery performance. Ru/CNTs electrocatalysts play a crucial role in solid-state Li–CO2 batteries. Its cathodes have a large surface area, discharge capacity, excellent reversibility, long cycle life, and low overpotential. Due to the increased active sites, this electrocatalyst could enhance the performance of CO2 reduction and evolution reactions. The solid-state Li–CO2 battery with Ru/CNTs cathode has a maximum discharge capacity of 4541 mAh g−1 and a battery life of 45 cycles with a potential difference of 1.24 V.