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1. First principles and experimental studies of empty Si ₄₆ as anode materials for Li-ion batteries

   https://doi.org/10.1557/jmr.2016.408  

   Chan, Kwai S.; Miller, Michael A.; Liang, Wuwei; Ellis-Terrell, Carol; Chan, Candace K. (December 2016, Journal of Materials Research)

   The objective of this investigation was to utilize the first-principles molecular dynamics computational approach to investigate the lithiation characteristics of empty silicon clathrates (Si 46 ) for applications as potential anode materials in lithium-ion batteries. The energy of formation, volume expansion, and theoretical capacity were computed for empty silicon clathrates as a function of Li. The theoretical results were compared against experimental data of long-term cyclic tests performed on half-cells using electrodes fabricated from Si 46 prepared using a Hofmann-type elimination–oxidation reaction. The comparison revealed that the theoretically predicted capacity (of 791.6 mAh/g) agreed with experimental data (809 mAh/g) that occurred after insertion of 48 Li atoms. The calculations showed that overlithiation beyond 66 Li atoms can cause large volume expansion with a volume strain as high as 120%, which may correlate to experimental observations of decreasing capacities from the maximum at 1030 mAh/g to 553 mA h/g during long-term cycling tests. The finding suggests that overlithiation beyond 66 Li atoms may have caused damage to the cage structure and led to lower reversible capacities. 

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2. Enabling Ultrathick Electrodes via a Microcasting Process for High Energy and Power Density Lithium‐Ion Batteries

   https://doi.org/10.1002/aenm.202201353  

   Plateau, Tazdik Patwary; Pham, Hiep; Zhu, Yaqi; Leu, Ming; Park, Jonghyun (July 2022, Advanced Energy Materials)

   Abstract Thickening electrodes is one effective approach to increase active material content for higher energy and low‐cost lithium‐ion batteries, but limits in charge transport and huge mechanical stress generation result in poor performance and eventual cell failure. This paper reports a new electrode fabrication process, referred to as µ‐casting, enabling ultrathick electrodes that address the trade‐off between specific capacity and areal/volumetric capacity. The proposed µ‐casting is based on a patterned blade, enabling facile fabrication of 3D electrode structures. The study reveals the governing properties of µ‐casted ultrathick electrodes and how this simultaneously improves battery energy/power performance. The process facilitates a short diffusion path structure that minimizes intercalation‐induced stress, improving energy density and cell stability. This work also investigates the issues with structural integrity, porosity, and paste rheology, and also analyzes mechanical properties due to external force. The µ‐casting enables an ultrathick electrode (≈280 µm) that more effectively utilizes NMC‐811 (LiNi_0.8Mn_0.1Co_0.1O₂) cathode and mesocarbon microbeads anode active materials compared to conventional thick electrodes, allowing high‐mass loading (35.7 mg cm⁻²), 40% higher specific capacity, and 30% higher areal capacity after 200 cycles, high C‐rate performance, and longer cycle life. 

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3. Co-axial fibrous silicon asymmetric membranes for high-capacity lithium-ion battery anode

   https://doi.org/10.1007/s10800-019-01343-w  

   Wu, Ji; Anderson, Christopher; Beaupre, Parker; Xu, Shaowen; Jin, Congrui; Sharma, Anju (January 2019, Journal of Applied Electrochemistry)

   Silicon as a promising candidate for the next-generation high-capacity lithium-ion battery anode is characterized by outstanding capacity, high abundance, low operational voltage, and environmental benignity. However, large volume changes during Si lithiation and de-lithiation can seriously impair its long-term cyclability. Although extensive research efforts have been made to improve the electrochemical performance of Si-based anodes, there is a lack of efficient fabrication methods that are low cost, scalable, and self-assembled. In this report, co-axial fibrous silicon asymmetric membrane has been synthesized using a scalable and straightforward phase inversion method combined with dip coating as inspired by the hollow fiber membrane technology that has been successfully commercialized over the last decades to provide billions of gallons of purified drinking water worldwide. We demonstrate that ~ 90% initial capacity of co-axial fibrous Si asymmetric membrane electrode can be maintained after 300 cycles applying a current density of 400 mA g−1. The diameter of fibers, size of silicon particles, type of polymers, and exterior coating have been identified as critical factors that can influence the electrode stability, initial capacity, and rate performance. Much enhanced electrochemical performance can be harvested from a sample that has thinner fiber diameter, smaller silicon particle, lower silicon content, and porous carbon coating. This efficient and scalable approach to prepare high-capacity silicon-based anode with outstanding cyclability is fully compatible with industrial roll-to-roll processing technology, thus bearing a great potential for its future commercialization. 

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4. A simple and scalable pre-lithiation approach for high energy and low cost lithium ion sulfur batteries

   Chao Shen, Donghao Ye (January 2020, Journal of the Electrochemical Society)

   Sulfur-polyacrylonitrile (S-PAN) composite has been developed as a novel composite cathode material to address many issues with conventional Li-S batteries (LSBs). In this study, a freestanding S-PAN-CNT composite is first developed as the cathode material for LSBs, which is capable to deliver a high specific capacity of 1458 mAh g-1 at 0.2C and a desirable high-rate performance of 1097 mAh g-1 at 2.0 C. Furthermore, a Li2S-PAN-CNT cathode is obtained via in-situ direct pre-lithiation of S-PAN-CNT composite, which exhibits an even improved discharge capacity, cycling performance, and rate capability. Lastly, we develop Li-ion sulfur full batteries based on both S-PAN-CNT and Li2S-PAN-CNT cathode. The excellent electrochemical performance and corresponding theoretical estimation both demonstrate that the proposed system as a promising metal-free Li-ion battery with a high specific capacity, good cycle life, and low cost. 

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5. Prelithiation of Alloy Anodes via Roll Pressing for Solid‐State Batteries

   https://doi.org/10.1002/adma.202508973  

   Wang, Congcheng; Jeong, Won_Joon; Nelson, Douglas_Lars; Sridhara, Hari; Anderson, Sophia_Nicolette; McDowell, Matthew_T (August 2025, Advanced Materials)

   Abstract Solid‐state batteries with alloy‐type negative electrodes can feature enhanced energy density and safety compared to conventional Li‐ion batteries. However, diffusional Li trapping within Li alloys often causes low initial Coulombic efficiency and leads to capacity loss with cycling. Here, a general roll‐pressing prelithiation method compatible with a variety of alloy‐type negative electrodes (silicon, aluminum, tin, and multi‐phase alloys) is introduced, which is shown to improve performance in solid‐state batteries. By warm‐rolling lithium foil of controlled thickness with various alloy‐type electrodes, both slurry‐cast and foil‐type electrodes can be uniformly prelithiated via direct chemical reaction. The prelithiated electrodes exhibit enhanced specific capacity and extended cycle life in batteries with Li₆PS₅Cl solid‐state electrolyte. Prelithiated multi‐phase foil electrodes with a tailored interface are shown to exhibit superior cycling stability down to 2 MPa stack pressure. This prelithiation technique offers a pathway to overcome intrinsic challenges in alloy anodes for solid‐state batteries. 

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