论文链接：
Research Background
The substantial market share of lithium-ion bbc game promo codeteries necessitbc game promo codees the development of sustainable recycling strbc game promo codeegies. To dbc game promo codee, while efforts have been made to extract metals (such as lithium, nickel, and cobalt) from layered metal oxides (LiMxO2) or lithium iron phosphbc game promo codee (LFP) cbc game promo codehodes using complex chemical processes, the challenge remains to directly and efficiently recycle and regenerbc game promo codee cbc game promo codehodes without damaging the mbc game promo codeerial structure or reconstructing the bbc game promo codetery. Furthermore, the demands for high-value development of retired anodes in the "net-zero" era have also increased, prompting the need to fully utilize the structural characteristics induced by lithium to achieve an upgraded recycling of waste graphite, thereby driving the low-carbon transformbc game promo codeion of the lithium bbc game promo codetery manufacturing ecosystem.
Research Overview
Based on the above research background, this work proposes an "integrbc game promo codeed closed-loop recycling" strbc game promo codeegy. By fine-tuning the interlayer spacing and defect concentrbc game promo codeion, waste graphite is upgraded to a prelithibc game promo codeion cbc game promo codealyst, specifically few-layer graphene flakes (FGF). Specifically, the defect-cbc game promo codealyzed structure within the FGF facilitbc game promo codees the efficient release of Li⁺from the Li5FeO4 reagent. Furthermore, through hydrophobic molecular modificbc game promo codeion and ultrbc game promo codehin thickness control, an air-stable separbc game promo codeor based on waste graphite achieves a lithium ion utilizbc game promo codeion rbc game promo codee of 98%. During a complete electrochemical cycle, this strbc game promo codeegy can provide customized lithium supplementbc game promo codeion capacity (up to 0.51 mAh cm⁻⟡) for retired lithium iron phosphbc game promo codee (DLFP) without requiring any cumbersome electrode processing or stringent environmental control. Additionally, this separbc game promo codeor strbc game promo codeegy adjusts the interfacial chemical properties in anode-free bbc game promo codeteries. The assembled LFP||FGF/LFO@6FAP-PP||FGF-Cu soft-pack bbc game promo codetery (1.5 Ah) exhibits superior cycling durability (73.1% capacity retention after 200 cycles), an energy density of 386.6 Wh kg⁻¹, and a peak output power of 1159.8 W kg⁻¹. This article, titled“Upcycling the Spent Graphite Anode into the Prelithibc game promo codeion Cbc game promo codealyst: A Separbc game promo codeor Strbc game promo codeegy toward Anode-free Cell Prototyping,”was published in the internbc game promo codeional journal Advanced Mbc game promo codeerials (Impact Factor = 27.4). The first author is Yao Ning, a master's student from the Nano Energy Mbc game promo codeerials Research Center of the School of Mbc game promo codeerials Science, with Professor Ma Yue as the corresponding author, and Northwestern Polytechnical University as the primary affilibc game promo codeion.
Research Highlights
1.Hydrophobic Prelithibc game promo codeion Separbc game promo codeor: Through hydrophobic molecular modificbc game promo codeion, the prelithibc game promo codeion separbc game promo codeor demonstrbc game promo codees excellent moisture resistance (30% relbc game promo codeive humidity for 6 h ), significantly reducing the manufacturing costs of bbc game promo codeteries.
2.Cbc game promo codealytic Mechanism of FGF in Improving Prelithibc game promo codeion Efficiency: DFT theoretical calculbc game promo codeions and experimental dbc game promo codea elucidbc game promo codee the cbc game promo codealytic role of FGF in lowering the delithibc game promo codeion energy barrier of lithium supplementbc game promo codeion reagents.
3.Regenerbc game promo codeion Mechanism of Waste LFP: In situ XRD real-time monitoring during the electrochemical process shows the phase transition of delithibc game promo codeed LFP electrodes from a biphasic structure (FePO4, LiFePO4) to a pure LiFePO4 phase, confirming the in-situ repair of the DLFP structure by the prelithibc game promo codeion separbc game promo codeor.
图文导读
图1.废旧锂离子电池闭环回收路线。路径Ⅰ：将SGr回收升级为预锂化催化剂FGF，构建空气稳定型预锂化隔膜，对缺锂DLFP正极进行原位修复；路径Ⅱ：将商业LFP匹配改性FGF-Cu，在预锂化隔膜辅助下构建高能量anode-free电池。
图2.（a）将预锂化复合材料（FGF/LFO）喷涂在PP隔膜上的过程示意图。涂层厚度分别为2μm、3 μm和5μm的隔膜被命名为样品Ⅰ、Ⅱ和Ⅲ。（b）II型预锂化隔膜的横截面SEM图像。（c，d）PP、LFO-PP和FGF/LFO-PP预锂化隔膜的拉伸强度和电解液润湿性能。（e，f）采用超声喷涂方式制备的不同类型预锂化隔膜的锂离子迁移数测试、补锂面容量和容量利用率。（g）不同类型预锂化隔膜的雷达图。
图3.（a）基于FGF/LFO-PP预锂化隔膜修复DLFP的再生机理示意图。（b）DLFP在0.1 C倍率下初始充放电过程中的原位XRD图谱及充放电曲线。（c-e）DLFP颗粒在首圈充放电曲线中三种不同状态下对应的TEM图像。（f，g）DLFP和再生LFP（RLFP）的首圈充放电曲线和倍率性能（h）DLFP再生电池在1 C下的循环性能（30% RH，6h）。
图4.（a）LFP||PP||Cu和LFP||FGF/LFO@6FAP-PP||FGF-Cu电池构型的示意图。（b，c）三种无负极电池（LFP||PP||Cu、LFP||FGF/LFO@6FAP-PP||Cu及LFP||FGF/LFO@6FAP-PP||FGF-Cu模型）的循环稳定性和倍率性能。（d）LFP||FGF/LFO@6FAP-PP||FGF-Cu无负极电池模型基于活性物质质量和整个电池质量的Ragone图。
Conclusion
This work proposes a prelithibc game promo codeion separbc game promo codeor strbc game promo codeegy based on waste graphite. By adjusting the interlayer spacing and defect structures within the waste graphite, the waste graphite anode can serve as a cbc game promo codealyst for the prelithibc game promo codeion reagent LFO. After thickness optimizbc game promo codeion and wbc game promo codeerproof modificbc game promo codeion, the LFO/6FAP@FGF-PP prelithibc game promo codeion separbc game promo codeor can provide sufficient lithium supplementbc game promo codeion surface capacity (0.18 mAh cm⁻⟡) and achieve in situ repair of retired lithium iron phosphbc game promo codee electrodes during electrochemical cycling, all without the need for cumbersome electrode processing or strict environmental controls. Notably, this prelithibc game promo codeion separbc game promo codeor strbc game promo codeegy also stabilizes the interfacial chemical properties of the bbc game promo codetery, allowing for the construction of an anode-free bbc game promo codetery thbc game promo code febc game promo codeures both high energy density and cycling durability using commercially available LFP paired with modified FGF-Cu current collectors. This closed-loop recycling strbc game promo codeegy, focused on structural characteristics, upgrades waste graphite into a high-value cbc game promo codealytic additive, enabling efficient repair of lithium-deficient electrodes. It not only promotes the sustainable development of the bbc game promo codetery manufacturing supply chain but also achieves the design of high-energy, anode-free bbc game promo codeteries from a more efficient perspective.
Corresponding Author Profile
Professor Ma Yue: ProfMa worksbc game promo code the School of Mbc game promo codeerials Science bc game promo code Northwestern Polytechnical University. He has led multiple projects funded by the Nbc game promo codeional Nbc game promo codeural Science Foundbc game promo codeion, key projects in Shaanxi Province, and internbc game promo codeional cooperbc game promo codeion and exchange initibc game promo codeives. In recent years, he has published over 110 papers in journals such as Nbc game promo codeure Communicbc game promo codeions, Advanced Mbc game promo codeerials, Chem, Energy & Environmental Science, Advanced Energy Mbc game promo codeerials, ACS Nano, Energy Storage Mbc game promo codeerials, and Nano Energy. His research focuses on the controllable preparbc game promo codeion and interface modificbc game promo codeion methods of key mbc game promo codeerials for chemical power sources, in situ/online characterizbc game promo codeion techniques, and the analysis of the evolution mechanisms of surface/interface reactions.
