Laser-engraved graphene architecture as an ultra-light freestanding lithium-free anode for lithium batteries

Abstract Breakthroughs in high-capacity anodes represent a critical frontier in the development of next-generation high-specific-energy storage systems. However, the current high-capacity anodes of lithium batteries are confronted with numerous challenges, including uncontrolled volume expansion, lithium dendrite growth, dead lithium, and unstable solid electrolyte interphase (SEI) films. Herein, we firstly employ laser engraving technology to fabricate an ultra-light freestanding graphene film with through-hole array and defect-rich edges, which serves as a lithium-free anode that integrates lithium-ion intercalation and metallic lithium deposition. During discharge, the defect structures at the pore edges facilitate the adsorption of lithium ions and their rapid intercalation between graphene layers, forming the LiCx framework. This enables the conversion of quasi-dead lithium through the solid-state pathway of Li → LiCx → Li+. Simultaneously, the vertically aligned through-holes homogenize ion flux and promote metallic lithium storage within the pores, thereby achieving high areal capacity, excellent reversibility, dendrite-free growth, and minimal volume change. As a result, this ultra-light freestanding lithium-free graphene anode (FLFGA) achieves highly reversible Li storage with 99.9% Coulombic efficiency (CE) over 1300 cycles and dendrite-free plating/stripping at a high areal capacity of 4 mAh·cm−2 (1350 mAh·g−1 anode). When paired with a high-loading LiFePO4 (LFP) cathode (11.5 mg·cm−2), the FLFGA||LFP full cell exhibits significantly enhanced cycling stability (500 cycles), outperforming most conventional Li metal battery, lean-Li battery, and anode-free Li battery systems. This work demonstrates a viable lithium-free anode strategy via laser-engraved graphene engineering, paving the way for durable, safe, and high-energy-density Li batteries.