2022-08-08 イリノイ大学シカゴ校(UIC)
実験では、研究者達は、水性亜鉛-二酸化マンガン電池を作り、100サイクルに渡ってテストした。電子顕微鏡を使って原子レベルの反応画像を撮影しながら、電池の放電と再充電を繰り返す実験を行った。
水素が二酸化マンガンのトンネル構造を損傷させ、電池の充電能力をさらに低下させることがわかった。これらの実験によって得られた情報は、亜鉛マンガン電池のメカニズムに関する原子レベルでの重要な知見を明らかにする。細胞レベルで何が起こっているのかがわかったので、より良い戦略を見つけるための羅針盤ができた。
＜関連情報＞
- https://today.uic.edu/understanding-how-rechargeable-aqueous-zinc-batteries-work/
- https://www.nature.com/articles/s41893-022-00919-3
持続可能な水系亜鉛-二酸化マンガン電池のためのインターカレーション化学の解明 Understanding intercalation chemistry for sustainable aqueous zinc–manganese dioxide batteries
Yifei Yuan,Ryan Sharpe,Kun He,Chenghang Li,Mahmoud Tamadoni Saray,Tongchao Liu,Wentao Yao,Meng Cheng,Huile Jin,Shun Wang,Khalil Amine,Reza Shahbazian-Yassar,M. Saiful Islam & Jun Lu
Nature Sustainability Published:08 August 2022
DOI:https://doi.org/10.1038/s41893-022-00919-3
Abstract
Rechargeable aqueous Zn–MnO2 technology combines one of the oldest battery chemistries with favourable sustainability characteristics, including safety, cost and environmental compatibility. However, the ambiguous charge storage mechanism presents a challenge to fulfil the great potential of this energy technology. Here we leverage on advanced electron microscopy, electrochemical analysis and theoretical calculations to look into the intercalation chemistry within the cathode material, or α-MnO2 more specifically. We show that Zn2+ insertion into the cathode is unlikely in the aqueous system; rather, the charge storage process is dominated by proton intercalation to form α-HxMnO2. We further reveal anisotropic lattice change as a result of entering protons proceeding from the surface into the bulk of α-MnO2, which accounts for the structural failure and capacity decay of the electrode upon cycling. Our work not only advances the fundamental understanding of rechargeable zinc batteries but also suggests the possibility to optimize proton intercalation kinetics for better-performing cell designs.
