A highly reversible glass-fiber-based flexible lithium anode via embedding lithophilic cobalt quantum dots

Nonconducting textile materials will be the skeleton of electrode for flexible battery in growing widespread applications in portable and wearable electronics, a fiber-based lithium anode is facing more challenges and has more important sense. Herein, a glass fiber was employed as supporting skeleton on which the nitrogen-doped carbon nanoflake array has been modified first to form a conductive layer, then the cobalt quantum dots were embedded in the layer to establish lithophilic sites, finally, a unique glass-fiber-based lithium anode (GFLA) has been achieved. Furthermore, the cross-linked fiber framework not only dramatically lessen the local current density, but the richer cavity also greatly alleviates the volume expansion problem. Thus, the GFLA electrode demonstrated a highly reversible and stable long-term cycling behavior with nondendritic. As expected, the GFLA electrode exhibits a high CE (similar to 98.64%) at 0.5 mA cm(-2) upon 1480 h in half-cell and a durable cycling with a small voltage hysteresis (20 mV) for 470 h at 4 mA cm(-2)/4 mAh cm(-2) in symmetrical-cell. Moreover, the GFLA@Li||LiFePO4 full-cell displays a capacity retention rate of up to 90.3% after 400 cycles, while the carbon fiber@Li||LiFePO4 is only 36.4%.

Automated summary

This study explores a unique glass fiber-based lithium anode and demonstrates its high reversibility and stability, as well as its dendrite-free structure, which can maintain high energy efficiency during long-term use.