Soft Carbon-Thiourea with Fast Bulk Diffusion Kinetics for Solid-State Lithium Metal Batteries

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• All-solid-state lithium-metal batteries (ASSLMBs) face challenges like low efficiency and short lifespans due to lithium dendrite growth.
• These dendrites impede ion transport, reduce battery performance, and pose safety risks.

Purpose of the Study:

• To design and develop a novel anode material for dendrite-free ASSLMBs.
• To enhance lithium-ion transport kinetics and improve battery performance and cycle life.

Main Methods:

• Fabrication of a multiple-diffusion-channel N,S-doped soft carbon with expanded layer spacing via thiourea calcination.
• Electrochemical characterization of the anode material in ASSLMBs.

Main Results:

• The N,S-doped carbon anode exhibits expanded layer spacing, facilitating superior Li+ transport within and between layers.
• Achieved record-high current density (15 mA cm⁻²), areal capacity (20 mAh cm⁻²), and energy density (403 Wh kg⁻¹).
• Demonstrated ultra-long cycle life (>13,000 cycles) and enabled pouch cells with >305 Wh kg⁻¹ energy density.

Conclusions:

• The developed N,S-doped carbon anode effectively suppresses lithium dendrite growth by improving bulk phase diffusion kinetics.
• This material represents a significant advancement for the practical application of ASSLMBs, offering high performance and durability.