Deciphering coulombic loss in lithium-ion batteries and beyond

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Lithium-ion batteries are crucial for energy storage, but predicting their lifespan is challenging.
• Coulombic efficiency is used to assess battery longevity, but its physical origins and correlation with capacity are unclear.
• Existing methods often lead to overestimations and paradoxical phenomena in battery lifespan evaluation.

Purpose of the Study:

• To elucidate the microscopic origins of coulombic losses in lithium-ion batteries.
• To establish a quantitative correlation between coulombic loss and battery capacity based on physical principles.
• To develop physics-informed criteria for accelerated lifespan evaluation and rational battery design.

Main Methods:

• Combining high-precision leakage current and open-circuit-voltage measurements.
• Applying principles of charge conservation to analyze electrode-electrolyte interfaces.
• Investigating diverse lithium-ion battery chemistries.

Main Results:

• Coulombic loss is shown to arise from a synergy between local charge neutrality and global charge compensation.
• A reconciled, quantitative correlation between coulombic loss and capacity is established.
• Systematic overestimations and paradoxical phenomena in existing chemistries are resolved.

Conclusions:

• The study provides a physics-based framework for understanding coulombic losses in lithium-ion batteries.
• This framework enables more accurate lifespan prediction and resolves discrepancies in current methodologies.
• Findings guide the rational design of long-life lithium-ion batteries and future energy storage systems.