Ambient laser process enables monolithic prelithiated silicon–graphene anodes

Researchers at Israel’s Tel Aviv University recently demonstrated a single-step laser process that simultaneously fabricates and prelithiates silicon-graphene anodes under ambient conditions, delivering virtually zero capacity decay over thousands of high‑rate cycles. The method directly addresses two key problems of silicon anodes – large volume changes and first‑cycle lithium loss – without relying on reactive lithium metal, moisture‑sensitive reagents, or multi‑step ex situ prelithiation.

The process starts from a ternary blend of phenolic resin, silicon nanoparticles (SiNPs), and a common lithium salt such as LiOH, Li₂CO₃, LiNO₃, LiF, or LiClO₄. Low‑power laser irradiation under ambient atmosphere generates localized temperatures above 2000 K and pressures exceeding 1 GPa, converting the resin into a porous, conductive laser‑induced graphene (LIG) matrix while driving solid‑state reactions that prelithiate the silicon surface and form stable interfacial phases. The result is a self‑standing, additive‑free SiNP/LIG film in which each nanoparticle retains a crystalline Si core for high capacity, wrapped by a ~10 nm lithium silicate shell that compensates first‑cycle lithium losses and chemically anchors the particles to the graphene scaffold.

a Schematic overview of the single-step, ambient, and low-power laser irradiation process applied to a blend of Li salt, phenolic resin, and SiNPs for the synthesis of self-standing, porous, prelithiated PL-SiNP/LIG composite anodes. b Molecular-scale schematic with the proposed laser irradiation mechanism of the ternary blend, inducing LIG formation while concomitantly triggers in situ prelithiation and encapsulation of SiNPs. c Demonstration of prelithiated SiNP/LIG anode synthesis with large-area sheet formation, highlighting the scalability of the process. Image from: Nano-Micro LettersThe process starts from a ternary blend of phenolic resin, silicon nanoparticles (SiNPs), and a common lithium salt such as LiOH, Li₂CO₃, LiNO₃, LiF, or LiClO₄. Low‑power laser irradiation under ambient atmosphere generates localized temperatures above 2000 K and pressures exceeding 1 GPa, converting the resin into a porous, conductive laser‑induced graphene (LIG) matrix while driving solid‑state reactions that prelithiate the silicon surface and form stable interfacial phases. The result is a self‑standing, additive‑free SiNP/LIG film in which each nanoparticle retains a crystalline Si core for high capacity, wrapped by a ~10 nm lithium silicate shell that compensates first‑cycle lithium losses and chemically anchors the particles to the graphene scaffold.

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