Abstract
The growth in electrified transportation has benefited from the massive worldwide research efforts used to discover and improve electrode materials and electrolytes. Nevertheless, lithium-ion batteries still suffer from a slow-charging limitation. Recently, it has been demonstrated that white light illumination of LiMn2O4 provokes faster charging, improving the kinetics of delithiation without the use of nanostructured active materials. In this work, we probe the mechanism of photo-accelerated fast charging and show that Mn d-d electronic transitions occurring under red light illumination are largely responsible for the increased charging rate. It is further demonstrated through X-ray absorption spectroscopy methods that LiMn2O4 Mn–Mn bond distances shorten after d-electron excitation. The shrinkage in the crystal volume beneficially contributes to delithiation kinetics by lowering the resistance to lithium-ion conduction. Advanced materials that can absorb light to modulate their structure may provide us with a new mechanistic pathway to pursue for increasing charge transfer rates.
Original language | English (US) |
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Article number | 101051 |
Journal | Cell Reports Physical Science |
Volume | 3 |
Issue number | 9 |
DOIs | |
State | Published - Sep 21 2022 |
Keywords
- fast charging
- lithium manganese oxide
- lithium-ion
- photo-chemistry
- photo-electrochemistry
ASJC Scopus subject areas
- General Chemistry
- General Materials Science
- General Engineering
- General Energy
- General Physics and Astronomy