| Mar 18, 2026 |
Laser process creates silicon-graphene battery anodes that barely lose charge
A single-step laser technique produces prelithiated silicon-graphene battery anodes with over 98% capacity retention after 2000 cycles under ambient conditions.
(Nanowerk News) A single-step laser process can create prelithiated silicon-graphene battery anodes under normal atmospheric conditions, producing electrodes that retain virtually all their capacity over thousands of charge-discharge cycles. The method, developed at Tel Aviv University by Professor Fernando Patolsky and colleagues, replaces the multi-step fabrication and reactive chemicals that have made silicon anode prelithiation difficult.
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Key Findings
- Prelithiated silicon nanoparticles embedded in laser-induced graphene retain more than 98% of their capacity after 2000 cycles at 5 A g⁻¹.
- The anodes deliver over 1700 mAh g⁻¹ with an initial coulombic efficiency above 97%, maintaining 83% capacity retention after 4500 cycles.
- The process works with common lithium salts and requires no binders, conductive additives, or post-processing steps.
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Why silicon anodes need prelithiation
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Silicon can store roughly ten times more lithium than the graphite used in most current battery anodes, but it swells dramatically during charging and shrinks again during discharge. This repeated expansion and contraction breaks down the electrode structure and causes rapid capacity fade.
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A separate problem is that silicon consumes a large share of available lithium during its first charge cycle to form a protective surface layer called the solid-electrolyte interphase. Prelithiation, the process of loading extra lithium into the anode before the battery is assembled, compensates for this loss. Existing methods, however, typically require reactive lithium metal, moisture-sensitive reagents, or elaborate multi-step procedures.
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How the laser process works
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The technique begins with a mixture of phenolic resin, silicon nanoparticles, and a common lithium salt. Suitable salts include lithium hydroxide, lithium carbonate, lithium nitrate, lithium fluoride, and lithium perchlorate. A low-power laser scans this blend under ambient atmosphere, generating extreme localized temperatures above 2000 K and pressures exceeding 1 GPa.
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These conditions simultaneously convert the resin into a porous, conductive graphene matrix and trigger solid-state reactions at the silicon surfaces that embed lithium into them. The entire synthesis and prelithiation occurs in one pass, with no secondary processing required.
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The resulting composite has a core-shell structure. Each silicon nanoparticle keeps its crystalline core, which preserves high charge storage ability. Around it forms a thin lithium silicate shell roughly 10 nm thick that compensates for first-cycle lithium losses and bonds the particle to the surrounding graphene scaffold.
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| Graphical abstract of the work. (Image: Reproduced from DOI:10.1007/s40820-026-02074-2, CC BY)
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Because the composite is self-standing, it needs no binders or conductive additives. This simplifies manufacturing and lowers material costs compared to conventional silicon anodes.
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Among the salts tested, lithium hydroxide produced the best performance. The researchers attribute this to alkaline-promoted densification of the precursor blend during laser processing, which improves contact between the silicon particles and the lithium source. All five salts yielded functional prelithiated composites, confirming the broad compatibility of the approach.
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Electrochemical performance
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At a current density of 5 A g⁻¹, the prelithiated electrodes kept more than 98% of their capacity through 2000 cycles with negligible decay. Capacity retention remained at 83% even after 4500 cycles, well above previously reported results for nano-silicon-based prelithiated anodes.
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At very high current densities of 10 A g⁻¹, the anodes still held up to 63% of their maximum capacity, showing strong suitability for fast-charging applications.
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Full cells paired with lithium iron phosphate cathodes showed no measurable capacity loss over 500 cycles at a 1C rate. This result confirms that the prelithiated anodes perform reliably not just in laboratory half-cell tests but also in complete battery configurations.
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Scaling toward production
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The researchers fabricated the composite in strips up to 20 cm long, with processing rates exceeding hundreds of square centimeters per hour. The method is also compatible with roll-to-roll manufacturing, suggesting a viable route to industrial-scale electrode production.
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The study, published in Nano-Micro Letters ("Laser-Driven Single-Step Synthesis of Monolithic Prelithiated Silicon-Graphene Anodes for Ultrahigh-Performance Zero-Decay Lithium-Ion Batteries"), was conducted by Avinash Kothuru, Gil Daffan, and Fernando Patolsky from the School of Chemistry and Department of Materials Science and Engineering at Tel Aviv University. By collapsing silicon anode synthesis and prelithiation into a single ambient laser step, the approach eliminates several fabrication barriers that have slowed the commercial use of high-capacity silicon anodes.
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