Bridge the Gaps Between Lab-Level Sodium-Ion Coin Cells and Practical Pouch Cells

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Sodium-ion batteries (SIBs) are attractive due to abundant sodium resources and similarities to lithium-ion battery manufacturing.
• SIBs offer advantages like low-temperature resistance and high rate capability.
• Advancing practical sodium-ion pouch cells is crucial, but a gap exists between lab-scale coin cells and real-world pouch cells.

Purpose of the Study:

• To systematically analyze the differences in energy density and cycle life between sodium-ion pouch cells and coin cells.
• To reveal the root causes of these performance discrepancies.
• To summarize research progress on cathode, anode, and electrolyte components for SIBs.

Main Methods:

• Comparative analysis of energy density and cycle life data from coin and pouch cells.
• Identification and analysis of intrinsic material defects in pouch cells.
• Review of recent advancements in SIB electrode and electrolyte materials.

Main Results:

• Significant differences in energy density and cycle life are observed between sodium-ion coin cells and pouch cells.
• Intrinsic material defects and interface instability are key factors contributing to pouch cell performance limitations.
• Progress in cathode, anode, and electrolyte materials is essential for improving pouch cell performance.

Conclusions:

• Bridging the performance gap between coin and pouch cells requires addressing material defects and interface issues.
• Standardization of assembly and testing protocols is proposed to facilitate the transition from lab to industry.
• This review provides insights to accelerate the development of practical sodium-ion batteries.