A Partially Stripped Succinonitrile Shield Rendering Air‐Stable Li5FeO4 Prelithiation Agent for Dendrite‐Free and Long‐Lifespan Lithium‐Ion Batteries

Why It Matters

The SN‑shielded LFO makes high‑capacity prelithiation practical, extending lithium‑ion battery life and enabling safer, higher‑energy designs for EVs and grid storage.

Key Takeaways

• SN coating prevents LFO alkalization in ambient air
• Retains 623.8 mAh g⁻¹ capacity after 1‑hour exposure
• Forms Li₃N‑rich SEI, enhancing interface stability
• Full cell delivers 167.4 mAh g⁻¹, 97.3% retention 200 cycles
• Simple wet‑chemical process scalable for industry

Pulse Analysis

The rapid growth of electric‑vehicle fleets and renewable‑energy storage has intensified demand for lithium‑ion batteries that combine high energy density with long cycle life. Prelithiation additives such as Li₅FeO₄ offer theoretical capacities exceeding 867 mAh g⁻¹, but their extreme air sensitivity has limited commercial adoption. By applying a thin succinonitrile (SN) layer, researchers create an air‑stable LFO@SN composite that retains most of its lithiation potential after brief exposure to ambient conditions, addressing a critical bottleneck in battery manufacturing.

Succinonitrile serves a dual purpose: it acts as a moisture barrier that blocks the spontaneous alkalization of LFO, and it partially dissolves in the electrolyte to generate a Li₃N‑rich solid electrolyte interphase (SEI). This SEI promotes rapid lithium transport while the residual SN adsorbs dissolved Fe ions, preventing detrimental side reactions. The resulting interphase stabilizes the electrode–electrolyte interface, curbing dendrite formation and extending cell lifespan. Such multifunctional coatings illustrate how molecular‑scale engineering can reconcile high capacity with robust chemical stability.

Performance data confirm the practical impact: LiFePO₄‖graphite full cells incorporating LFO@SN deliver 167.4 mAh g⁻¹ discharge capacity and maintain 97.3% capacity after 200 cycles, outperforming uncoated counterparts. The wet‑chemical coating process is straightforward, low‑cost, and compatible with existing slurry‑casting lines, suggesting easy scale‑up for battery manufacturers. As the industry pushes toward higher‑energy, longer‑lasting packs, air‑stable prelithiation additives like LFO@SN could become a cornerstone technology for next‑generation lithium‑ion batteries.