Aluminum foil negative electrodes with multiphase microstructure for all-solid-state Li-ion batteries.

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Metal alloys with lithium offer high theoretical capacity for rechargeable batteries.
• Limited reversibility of these alloys in liquid electrolytes hinders performance.

Purpose of the Study:

• To investigate non-pre-lithiated aluminum-indium alloy negative electrodes in all-solid-state Li-ion cells.
• To improve reversibility and rate capability of negative electrodes for high-energy batteries.

Main Methods:

• Fabrication of aluminum-indium alloy microstructures on aluminum foil.
• Assembly of lab-scale all-solid-state Li-ion cells using a solid-state electrolyte and a layered oxide positive electrode.
• Electrochemical testing to evaluate cycling stability and capacity at high current densities.

Main Results:

• Stable cycling over hundreds of cycles achieved with practically relevant areal capacities.
• High current densities (6.5 mA cm⁻²) demonstrated improved rate behavior and enhanced reversibility.
• The multiphase Al-In microstructure with a distributed LiIn network is key to performance.

Conclusions:

• Metallurgical design of negative electrodes offers a pathway to improved all-solid-state batteries.
• Simplified manufacturing processes are possible with this approach.
• Aluminum-indium alloys show promise for next-generation energy storage solutions.