Selection and Surface Modifications of Current Collectors for Anode-Free Polymer-Based Solid-State Batteries.

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Anode-free batteries (AFB) offer a simpler, cost-effective, and sustainable energy storage solution by eliminating the conventional anode.
• While liquid electrolyte AFBs are common, solid-state variants are less explored.
• A key challenge in AFBs is the poor reversibility of lithium plating and stripping at the anode.

Purpose of the Study:

• To investigate surface modifications of anode current collectors for solid-state anode-free batteries.
• To evaluate the impact of composite coatings on the electrochemical performance of these batteries.
• To understand failure mechanisms in solid-state AFBs through post-mortem analysis.

Main Methods:

• Tested various metal foils as anode current collectors, identifying copper as optimal.
• Developed composite coatings of carbon, metal nanoparticles (Ag, Sn, Zn), and binder for copper foil modification.
• Systematically studied the electrochemical performance of coated solid-state anode-free pouch cells using PEO electrolyte and LiFePO4 cathode.
• Performed post-mortem analysis to investigate failure modes.

Main Results:

• Copper foil demonstrated promising performance as an anode current collector.
• Surface modifications with specific composite coatings significantly impacted electrochemical performance.
• Identified key failure mechanisms through detailed post-mortem analysis.

Conclusions:

• Surface-modified copper current collectors are crucial for enhancing the performance of solid-state anode-free batteries.
• Understanding failure mechanisms is essential for future improvements in AFB technology.
• This study provides insights into optimizing solid-state AFB design for better reversibility and longevity.