Related Experiment Video
Updated: May 10, 2026
08:18
Protocol of Electrochemical Test and Characterization of Aprotic Li-O2 Battery
Published on: July 12, 2016
Unlocking Electrochemical-Driven Surface Oxygen Vacancies-Regulated Cathode-Electrolyte Interphase for Stabilizing
Chenxi Yan1,2, Xing Liu2, Xuanlong He2
1College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen, 518060, People's Republic of China.
Nano-Micro Letters
|May 8, 2026
Summary
Surface oxygen vacancies (OVs) in lithium-ion battery cathodes control cathode-electrolyte interphase (CEI) formation, enhancing battery durability. This study reveals OVs stabilize the CEI, improving capacity retention and cycle life.
Area of Science:
- Materials Science
- Electrochemistry
- Battery Technology
Background:
- Stable cathode-electrolyte interphases (CEIs) are crucial for lithium-ion battery (LIB) durability.
- CEI formation chemistry is complex, hindering rational design for improved performance.
Purpose of the Study:
- To demonstrate how surface oxygen vacancy (OV) concentration regulates CEI thickness and composition.
- To elucidate the mechanism of OV-mediated CEI modulation for enhanced LIB performance.
Main Methods:
- In situ strategy using Li₂C₄O₄ incorporation into LiCoO₂ (LCO) to generate surface OVs during cycling.
- Combined experimental techniques (including ¹⁸O isotope labeling and time-of-flight secondary ion mass spectrometry) and theoretical calculations.
- Analysis of CEI composition (LiF/LiₓPOyF<0xE2><0x82><0x93>) and correlation with OV concentration.
Main Results:
- Surface OVs enhance interfacial electron/Li⁺ migration and stabilize the CEI.
- Direct experimental evidence shows surface lattice oxygen is the primary source for CEI oxygen-containing products.
- A linear correlation between Li₂C₂O₄ content, OV concentration, and LiF/LiₓPOyF<0xE2><0x82><0x93> ratio in the CEI was established.
- OV-rich LCO cathodes showed 71.1% capacity retention after 600 cycles, significantly outperforming bare LCO (23.9%).
Conclusions:
- Surface OVs play a critical role in prolonging LIB cycle life by modulating CEI chemistry.
- This study establishes a new design principle for tailoring cathode interfaces and CEI composition.
- The findings are validated in high-voltage applications and other cathode materials like NCM811.
Related Concept Videos
03:12Batteries and Fuel Cells
A battery is a galvanic cell that is used as a source of electrical power for specific applications. Modern batteries exist in a multitude of forms to accommodate various applications, from tiny button batteries such as those that power wristwatches to the very large batteries used to supply backup energy to municipal power grids. Some batteries are designed for single-use applications and cannot be recharged (primary cells), while others are based on conveniently reversible cell reactions that...
01:28Electrochemical Cells
Electrochemical cells are systems that convert chemical energy into electrical energy or use electrical energy to drive chemical reactions. They consist of two electrodes in contact with an electrolyte, where redox reactions enable electron transfer. Most electrochemical cells include two half-cells connected by an external wire for electron flow and a salt bridge for ion flow. The salt bridge contains an electrolyte solution and maintains charge neutrality by allowing ions—not electrons—to...
02:47Voltaic/Galvanic Cells
Spontaneous Chemical Reactions
Spontaneous redox reactions occur abundantly in nature. The chemical reaction occurring in a disposable AA battery powering our remote controls is one such example of a spontaneous redox reaction. Another example is the immersion of coiled copper wire into an aqueous silver nitrate solution. The reaction shows a gradual, visually impressive color change from colorless to bright blue and the formation of a grey precipitate on the copper wire. In this experiment,...
Spontaneous redox reactions occur abundantly in nature. The chemical reaction occurring in a disposable AA battery powering our remote controls is one such example of a spontaneous redox reaction. Another example is the immersion of coiled copper wire into an aqueous silver nitrate solution. The reaction shows a gradual, visually impressive color change from colorless to bright blue and the formation of a grey precipitate on the copper wire. In this experiment,...
03:00Electrolysis
In a galvanic cell, the electrical work is done by a redox system on its surroundings as electrons produced by the spontaneous redox reactions are transferred through an external circuit. Alternatively, an external circuit does work on a redox system by imposing a voltage sufficient to drive an otherwise nonspontaneous reaction in a process known as electrolysis. For instance, recharging a battery involves the use of an external power source to drive the spontaneous (discharge) cell reaction in...