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1. Protective Spinel Coating for Li1.17Ni0.17Mn0.50Co0.17O2 Cathode for Li-Ion Batteries through Single-Source Precursor Approach

   https://doi.org/10.3390/nano10091870  

   Shevtsov, Andrey; Han, Haixiang; Morozov, Anatolii; Carozza, Jesse C.; Savina, Aleksandra A.; Shakhova, Iaroslava; Khasanova, Nellie R.; Antipov, Evgeny V.; Dikarev, Evgeny V.; Abakumov, Artem M. (September 2020, Nanomaterials)

   null (Ed.)

   The Li1.17Ni0.17Mn0.50Co0.17O2 Li-rich NMC positive electrode (cathode) for lithium-ion batteries has been coated with nanocrystals of the LiMn1.5Co0.5O4 high-voltage spinel cathode material. The coating was applied through a single-source precursor approach by a deposition of the molecular precursor LiMn1.5Co0.5(thd)5 (thd = 2,2,6,6-tetramethyl-3,5-heptanedionate) dissolved in diethyl ether, followed by thermal decomposition at 400 °C inair resulting in a chemically homogeneous cubic spinel. The structure and chemical composition of the coatings, deposited on the model SiO2 spheres and Li-rich NMC crystallites, were analyzed using powder X-ray diffraction, electron diffraction, high angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), and energy-dispersive X-ray (EDX) mapping. The coated material containing 12 wt.% of spinel demonstrates a significantly improved first cycle Coulombic efficiency of 92% with a high first cycle discharge capacity of 290 mAhg−1. The coating also improves the capacity and voltage retention monitored over 25 galvanostatic charge–discharge cycles, although a complete suppression of the capacity and voltage fade is not achieved. 

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2. Polypyrrole coated δ-MnO ₂ nanosheet arrays as a highly stable lithium-ion-storage anode

   https://doi.org/10.1039/D0DT01658F  

   Sui, Yiming; Liu, Chaofeng; Zou, Peichao; Zhan, Houchao; Cui, Yuanzheng; Yang, Cheng; Cao, Guozhong (June 2020, Dalton Transactions)

   Manganese dioxide (MnO 2 ) with a conversion mechanism is regarded as a promising anode material for lithium-ion batteries (LIBs) owing to its high theoretical capacity (∼1223 mA h g −1 ) and environmental benignity as well as low cost. However, it suffers from insufficient rate capability and poor cyclic stability. To circumvent this obstacle, semiconducting polypyrrole coated-δ-MnO 2 nanosheet arrays on nickel foam (denoted as MnO 2 @PPy/NF) are prepared via hydrothermal growth of MnO 2 followed by the electrodeposition of PPy on the anode in LIBs. The electrode with ∼50 nm thick PPy coating exhibits an outstanding overall electrochemical performance. Specifically, a high rate capability is obtained with ∼430 mA h g −1 of discharge capacity at a high current density of 2.67 A g −1 and more than 95% capacity is retained after over 120 cycles at a current rate of 0.86 A g −1 . These high electrochemical performances are attributed to the special structure which shortens the ion diffusion pathway, accelerates charge transfer, and alleviates volume change in the charging/discharging process, suggesting a promising route for designing a conversion-type anode material for LIBs. 

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3. Revisiting Discharge Mechanism of CF _x as a High Energy Density Cathode Material for Lithium Primary Battery

   https://doi.org/10.1002/aenm.202103196  

   Sayahpour, Baharak; Hirsh, Hayley; Bai, Shuang; Schorr, Noah_B; Lambert, Timothy_N; Mayer, Matthew; Bao, Wurigumula; Cheng, Diyi; Zhang, Minghao; Leung, Kevin; et al (December 2021, Advanced Energy Materials)

   Abstract Lithium/fluorinated graphite (Li/CF_x) primary batteries show great promise for applications in a wide range of energy storage systems due to their high energy density (>2100 Wh kg^–1) and low self‐discharge rate (<0.5% per year at 25 °C). While the electrochemical performance of the CF_xcathode is indeed promising, the discharge reaction mechanism is not thoroughly understood to date. In this article, a multiscale investigation of the CF_xdischarge mechanism is performed using a novel cathode structure to minimize the carbon and fluorine additives for precise cathode characterizations. Titration gas chromatography, X‐ray diffraction, Raman spectroscopy, X‐ray photoelectron spectroscopy, scanning electron microscopy, cross‐sectional focused ion beam, high‐resolution transmission electron microscopy, and scanning transmission electron microscopy with electron energy loss spectroscopy are utilized to investigate this system. Results show no metallic lithium deposition or intercalation during the discharge reaction. Crystalline lithium fluoride particles uniformly distributed with <10 nm sizes into the CF_xlayers, and carbon with lower sp²content similar to the hard‐carbon structure are the products during discharge. This work deepens the understanding of CF_xas a high energy density cathode material and highlights the need for future investigations on primary battery materials to advance performance. 

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4. Synthesis and performance of nanostructured silicon/graphite composites with a thin carbon shell and engineered voids

   https://doi.org/10.1016/j.electacta.2017.10.198  

   Ashuri, M.; He, Q.; Liu, Y.; Emani, S.; Shaw, L. (December 2017, Electrochimica acta)

   Utilizing silicon as an anode material for Li-ion batteries has been the subject of many studies. However, due to the huge volume change of silicon during lithiation, the electrochemical performance of silicon is poor. Here, we have investigated a novel yet simple approach to synthesize nanostructured silicon/graphite composites with a carbon coating and engineered voids. High-energy ball mill is employed to convert micrometer-sized silicon and graphite to nanostructured silicon/graphite composite building blocks, while a thin carbon coating is applied to encapsulate these composite agglomerates, followed by partial etching of silicon to create engineered voids inside the composite agglomerates. The batteries made with this tailored nanostructure exhibit improved electrochemical performance over the counterparts made with silicon nanoparticles and exhibited a specific capacity of ~1800 mA h g-1 discharge capacity at the first cycle, 580 mA h g-1 after 40 cycles, and 350 mA h g-1 after 300 cycles. This study has established a novel method scalable at industry environment and capable of producing low cost Si anodes and clearly shown that the cycle stability of the tailored nanostructure improves with increasing engineered voids in the range we have investigated. 

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5. Revealing the Micro‐Size Effect in Alloy Anodes for High‐Capacity and Long‐Cycling Sulfide‐Based Solid‐State Batteries

   https://doi.org/10.1002/smll.202504481  

   Ullah, Irfan; Qiu, Shen; Chang, Songyang; Hou, Wentao; Cruz, Dalice_M Piñero; Morell, Gerardo; Wu, James; Chen, Zhongfang; Wu, Xianyong (June 2025, Small)

   Abstract Solid‐state batteries (SSBs) are competitive contenders for energy storage due to their inherent safety and high energy. However, the lack of an appropriate anode has hindered their development. Graphite and lithium metal are widely used anode materials, but graphite suffers from a low capacity, whereas lithium metal presents severe dendrite and reactivity challenges. Herein, the promising performance of micro‐sized alloys is demonstrated as high‐capacity and long‐cycling anodes for SSBs. Using antimony as a model anode, its full theoretical capacity (660 mAh g⁻¹), high‐rate capability (3 A g⁻¹), and long cycling life (1000–2000 cycles) is achieved at room temperature. Comparative studies further reveal an overlooked “micro‐size effect”, where micro‐sized alloys establish more efficient electron/ion conduction pathways, significantly exceeding their nano‐sized counterparts. This micro‐size effect challenges the conventional belief that nano‐sized alloys always outperform micro‐sized ones. Based on this discovery, similarly high performance of other micro‐alloys (lead and bismuth) in SSBs is further demonstrated. Given the additional benefits of easy synthesis, low cost, high tap density, and high stability, micro‐sized alloys hold great promise as excellent anode candidates for SSBs. 

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