Increased electric vehicle adoption has expanded the number of unique fast charging profiles, further complicating infrastructure planning. In this study we characterize heterogeneity in real-world electric vehicle (EV) fast charging profiles across different vehicle models to identify key factors and to suggest implications for future profile design. We create a dataset from publicly available information then build a queuing model to understand throughput and electricity demand on high travel days. We quantify uncertainty in the number of EVs that can move through a charging station by comparing a Monte Carlo simulation to the deterministic throughput of a single repeated fast charging profile for each vehicle charged. Our findings show heterogeneity is significant for a 12 hour charging window, varying from 14 to 57 vehicles. Modeling diverse profiles or ensuring proper representation of the EV population should be considered when modeling infrastructure.

Lithium and Manganese Rich (LMR) layered oxide [[EQUATION]] offers exceptional reversible specific capacities but suffer from voltage fade, phase instability, and kinetic limitations especially at lower states of charge. This study systematically evaluates a hierarchical conductive architecture combining one-dimensional (1D) Single-Walled Carbon Nanotubes (SWCNTs) and two-dimensional (2D) Graphene to alleviate these shortcomings. We demonstrate that a relatively dense hybrid network forms a robust 3D scaffold where SWCNTs and graphene sheets coat and interconnect active particles, resulting in an improved performance at relatively high electrode densities of 2.7g/cc, even at lower states of charge. Electrochemical characterization reveals that the hybrid cathode delivers superior specific capacity (245 mAh/g at C/20) and rate capability (104 mAh/g at 5C) compared to single-component additives, while exhibiting remarkable resilience to calendering. Furthermore, Raman spectroscopy and GITT-EIS analysis confirm that this architecture not only reduces interfacial resistivity but also exerts a stabilization effect that suppresses the detrimental layered-to-spinel phase transformation and preserves [[EQUATION]] redox activity. These findings highlight the role of multi-scale conductive networks in stabilizing the cathode interface and enabling high energy density and high power density operations.

ElyteOS is a graphical user interface written in Python 3.8.3 that enables the automation of the processes of electrolyte preparation, measurement, data storage, and data visualization. It provides a user-friendly interface and acts as a framework for automating lab equipment with different commands as well as managing the procedures of the experiments. Meanwhile, ElyteOS automatically saves the experimental data in a database and provides data searching and visualization tools for researchers. Therefore, ElyteOS not only facilitates electrolyte research but also offers potential for optimizing battery performance and advancing battery technologies.

In the U.S., the transportation sector accounts for approximately 29% of total greenhouse gas emissions due to the combustion of fossil fuels. Within this sector, passenger vehicles and trucks are the primary contributors to these emissions. This situation makes the transition to electric vehicles (EVs) a crucial strategy for reducing reliance on fossil fuels. Recent government incentives and advancements in lithium-ion battery technology have accelerated EV adoption. However, challenges such as slow charging speeds, rapid performance degradation, and limited driving range remain major barriers to EV’s widespread implementation. Additionally, due to geopolitical challenges surrounding cobalt procurement, it is essential to explore alternative materials beyond NMC to further accelerate EV adoption. To address these concerns, this study focuses on the development of cobalt (Co)-free and low-nickel (Ni) cathodes capable of fast charging at a 10 C-rate, while maintaining a reasonable energy density and cycle life. First, we screened the fast-charging performance from various Co-free and low-Ni cathode materials, including LiFePO 4 , LiFe 1-x Mn x PO 4 , LiNi 0.5 Mn 1.5 O 4 , and lithium- and manganese-rich layered oxides. The charging acceptance rate of cathodes varies significantly depending on their crystal structure and redox couples. Following material selection, optimization efforts focused on electrode microstructural parameters such as particle size, types of conductive carbon, electrode thickness and porosity. This effort is particularly important for maintaining good fast-charging performance in cathodes with high mass loading (~ 3 mAh/cm 2 ). Beyond microstructural optimization, finding electrolyte compositions that support a stable cathode electrolyte interphase (CEI) and anode’s solid electrolyte interphase (SEI) is crucial for achieving long-term fast-charging performance at 10C-rate. We will also present that conventional half-cells with metallic lithium anodes significantly underperform in fast-charging applications, primarily due to abrupt electro-chemo-mechanical degradation at the lithium/electrolyte interphase. This degradation not only reduces fast-charging performance but also leads to premature cell failure. To solve this problem, we propose the use of Li 4 Ti 5 O 12 (LTO) anodes to more accurately evaluate the true fast-charging performance of cathodes. Due to their high Li-ion diffusivity and electrochemical stability in contact with conventional liquid electrolytes, cathode/LTO full-cells can mitigate severe artifacts associated with anode reactions, including Li plating, dendrite formation, and SEI layer development. Building on these efforts, we present the successful development of cathodes with an areal capacity of ~ 3 mAh/cm 2 , capable of sustaining prolonged 10C fast-charging performance in full-cells paired with LTO anodes. These results provide valuable insights into material and electrode engineering strategies that can further enhance the viability of fast-charging EVs, contributing to the broader adoption of sustainable transportation solutions.

This study investigates electrolyte consumption during the formation cycle of lithium-ion pouch cells through the integrated use of Nuclear Magnetic Resonance (NMR) spectroscopy and differential capacity (dQ/dV) analysis. By employing deuterated acetonitrile (ACN-d3) as the extraction solvent to facilitate NMR analysis, we quantitatively assess the degradation of electrolyte additives and solvent components across a range of voltages. By combining NMR and dQ/dV analysis, we gain a deeper understanding of how electrolytes break down and react through reduction and oxidation. These insights could help us develop more accurate models to predict battery degradation and performance. Early results indicate that NMR and dQ/dV findings align well, underscoring the potential of combining these techniques to accurately investigate electrolyte behavior during the formation process. This research represents a significant step forward in harnessing the combined power of NMR spectroscopy and dQ/dV analysis to advance the field of lithium-ion battery research.

Quick and inexpensive production of cathode materials for lithium-ion batteries is important for cost reduction of electric vehicle battery cells. Microwave heating is of interest for its ability to couple with high dielectric loss materials, providing rapid and uniform heat transfer. Previous work has investigated the effects of rapid cooling rate on the structure and performance of layered lithium-rich nickel manganese oxide (LMR) cathodes, 1 but to our knowledge, no studies have explored similar effects from rapid heating rate. Further, microwave-assisted (MW) solid-state synthesis of LMR has been unexamined. In this work, we investigate the reaction time and power required for MW synthesis of LMR and compare MW synthesized materials to the structure, morphology, and electrochemical performance of materials synthesized via conventional solid-state routes. Co-precipitated Ni 0.3 Mn 0.7 (OH) 2 and Li 2 CO 3 precursors were mechanically milled, then 1) hydraulically pressed into uniform pellets for MW heating using a SiC susceptor in a domestic 1200 W inverter microwave oven (2.45 GHz frequency) for up to 20 minutes and 720 W, or 2) conventionally heated/sintered via rotary hearth kiln for 24 hours. X-ray diffraction (XRD) and scanning electron microscopy (SEM) is used to characterize and compare the synthetic routes. Preliminary data suggests MW heating at power/time combinations of 360 W/15 min, 360 W/20 min, 480 W/10 min, and 720 W/10 min enables successful decomposition of Li 2 CO 3 , and 720 W/10 min MW heating conditions create a phase pure material with large grains. Figure 1 compares XRD data with SEM insets for LMR synthesized via a) MW heating at 720 W/10min, and b) conventional heating. Additional XRD, SEM, and electrochemical data will be presented. References: 1. Sven Burke and Jay F. Whitacre 2020 J. Electrochem. Soc. 167 160518 Figure 1

This study developed an accelerated stress test using low salt concentration and low formation temperatures to study the degree of passivation of the solid electrolyte interface (SEI) for different electrolyte formulations in lithium-ion pouch cells. Using differential capacity analysis, we can characterize the degree of passivation of additives under various conditions by looking at the degree of linear carbonate reduction. Using this technique, we observe that an electrolyte containing fluoroethylene carbonate or a mixture of vinylene carbonate and ethylene sulfate as additives passivates better than an electrolyte containing only vinylene carbonate as an additive, consistent with long-term cycling performance. This technique also allowed us to discover that additive-free electrolytes that contain low-viscosity solvents, such as methyl acetate, passivate the anode better by acting as graphite exfoliation inhibitors. We hope that the developed technique can be used to accelerate the discovery of new high-performance electrolytes.

This study investigates the formation and properties of the solid electrolyte interface (SEI) in lithium-ion batteries under varying salt concentrations (0.4M, 0.8M, 1.2M) and low formation temperatures. This method was used as a formation accelerated stress test (FAST) to evaluate the impact of different solvent blends and additives on anode passivation using the reduction rate of ethyl methyl carbonate (EMC) seen in the differential capacity of cells containing them as a performance metric. Electrolytes containing a mixture of vinylene carbonate and ethylene sulfate showed superior passivation, while a 3:7 mixture of fluoroethylene carbonate and ethyl methyl carbonate proved to be the most effective at passivating. Furthermore, the low-viscosity solvents methyl acetate and acetonitrile significantly enhanced SEI passivation during formation at the anode due to lower graphite exfoliation. We also show that the differential capacity data correlate with long-term cycling performance for some of the chemistry studied here. These results provide valuable insights for the efficient design of a new formation accelerated stress test (FAST) that could accelerate the discovery of high-performance electrolytes through rapid monitoring of SEI passivation during formation.

The pore structure of lithium-ion battery electrodes heavily influences ion transport and thus their deliverable capacity, especially at higher rates. Ideally, a gradient pore distribution favoring higher porosity near the separator side can enable faster ion transport at higher cycling rates. We present here a two-layer heterogenous cathode design using traditional NCM 811 material featuring a three-dimensional design space of this cathode design. An efficient characterization technique that combines fast micrometer-scale X-ray computed tomography and pore network modeling was developed, providing critical information regarding the ion transport pathways inside the cathode. Based on the X-ray CT data and performance characteristics obtained, we created a comprehensive profile of cathode rate performance as a function of their pore distribution with easily identifiable advantaged configurations for different cycling scenarios.

Previous attempts to enhance the stability and performance of MnO2-based cathodes for use in aqueous alkaline electrolytes, primarily KOH-based, have relied on a range of additives. This work demonstrates that the fast capacity decay of the MnO2-based cathode materials in alkaline electrolytes is mainly due to spontaneous manganese dissolution when cycling through the second-electron reaction voltage range. Reducing relative electrolyte content and using carbon materials that have a high specific surface area suppresses manganese dissolution and thus extends the cycle life of the electrode material while reducing overall battery costs. Moreover, reducing the size of the MnO2 particles and decreasing the cycling rate are found to increase manganese dissolution and negatively impact the performance of the electrode material, indicating a sensitivity to material surface area. Lastly, Fe-MnO2-based low-cost battery chemistry was also demonstrated based on the second electron reaction of the MnO2 in an electrolyte lean environment, which could be promising for grid-level energy storage.

Currently, the second-life Li-ion battery (LIB) landscape lacks a widely accepted safety standard for determining the viability of retired batteries for reuse.1 While the impact of abusive conditions on battery failures, such as toxic gas releases, fires, and explosions, has been studied extensively, the understanding of how aging affects the likelihood of thermal runaway under normal use conditions remains limited. This knowledge gap underscores the critical need for a deeper understanding of material degradation throughout the LIB lifecycle and its direct safety implications. In response, researchers are exploring advanced characterization methods to deconvolve and identify degradation behaviors, typically using lab-aged cells. These methods, which range from non-destructive evaluation to post-mortem analyses, have revealed various degradation modes (such as active material loss and Li inventory loss) and mechanisms (including Li plating, SEI growth and decomposition, transition metal dissolution, and particle cracking).2 However, the variability of these degradation modes in real-world battery packs remains poorly understood, making it challenging to estimate the likelihood of thermal runaway. A precise statistical understanding of these degradation mechanisms is essential for developing robust safety standards and maximizing the economic benefits of reusing LIBs. In this work, we apply differential voltage analysis to assess the statistical distribution of active material loss in a retired 1,536-cell hybrid-vehicle battery pack (see Ref. 3 for pack details).3 Initially, we measured the capacity and ohmic resistance of 1,500 cells (98% of the pack) using galvanostatic cycling at a rate of 1C (Fig. 1A-D). We then implemented k-medoids clustering to categorize the cells based on their capacity and resistance (Fig. 1E). The representative medoid cell from each cluster was then selected for further analysis at a slower C/10 cycling rate to gather dV/dQ data. Using open-source software provided by Dahn et al.,4 we fit the measured dV/dQ curves to reference curves collected from a LiFePO4 cathode vs. Li/Li+ and a graphite anode vs. Li/Li+ half-cells (the latter was provided by with the dV/dQ software). The fitting process yields 4 parameters: mG (active mass of the graphite anode), mLFP (active mass of the LFP cathode), 𝛿 LFP (LFP cathode slippage), and 𝛿 G (graphite anode slippage). Active material loss and slippage are then calculated relative to an uncycled cell with mG = 8.1 g and mLFP = 13 g. Fig. 1 summarizes the SOH of 1,500 cells (A-C), the cell categories and representative cells determined via k-medoid clustering (D), the dV/dQ curve-fitting method (E), and example dV/dQ curve-fitting results for 2 cells (F). The cell capacities (nominally 2.3 to 2.5 Ah) ranged from 0.0 to 2.2 Ah and their direct-current internal resistances (DCIR), which started at 10 mΩ when newly manufactured, ranged from 30 to 1000 mΩ. For two example cells (Fig. 1F), a -24% and +22% difference in % initial capacity (PIC) and DCIR, respectively, corresponded to a 150% increase in active graphite loss, a 99% increase in active LFP loss and a 6.7% difference in slippage (where 𝛿 = 𝛿 G - 𝛿 LFP ). In this presentation, we will expand on these initial results and will summarize our findings on the distribution of capacity, resistance, active material loss, and Li inventory loss across the entire pack. References Christensen, P. A., Mrozik, W. & Wise, M. S. A Study on the Safety of Second-Life Batteries in Battery Energy Storage Systems. UK BEIS/OPSS Report (2021). Li, A. G., West, A. C. & Preindl, M. Applied Energy 316, 119030 (2022). DOI: 10.1016/j.apenergy.2022.119030. Ramirez-Meyers, K., Rawn, B. & Whitacre, J. F. J. Energy Storage 59, 106472 (2023). DOI: 10.1016/j.est.2022.106472. Dahn, H. M., Smith, A. J., Burns, J. C., Stevens, D. A. & Dahn, J. R. J. Electrochem. Soc. 159, A1405–A1409 (2012). DOI: 10.1149/2.013209jes. Figure 1: A-D summarize the SOH of 1,500 cells. A) Charge and discharge curves, V(Q), at a 1C rate (that is, current = 2.0 A). B and D) Capacity and DCIR distributions. C) K-medoids clustering using z-scores (normalized capacity and DCIR values) shows representative cells as medoids of each cluster. E) An example of fitting measured dV/dQ (black) to dV/dQ calculated from the LFP cathode (blue) and graphite anode (purple) references. F) Comparative example of electrode mass and slippage calculations obtained from dV/dQ analysis. * = outliers are exclud ed. DCIR = direct-current internal resistance. LAM = Loss of active material. LFP = LiFePO4. PIC = Percent of initial capacity. Z-score = (Value – Mean)/Standard Deviation. Figure 1

Garnet-type Li6.4La3Zr1.4Ta0.6O12 (LLZTO) has been spotlighted as a promising solid-state-electrolyte for all-solid-state lithium metal batteries (ASSBs) due to high ionic conductivity, superior chemical stability against Li metal, and broad window potential (0~5 V versus Li/Li+). However, an insufficient solid-solid contact between the electrode and electrolyte brings about high interface resistance, low Coulombic efficiency, and large voltage polarization during cycling. To overcome these challenges, it is a desirable tactic to introduce an ionic conductive polymer interlayer such as novel modified polyethylene oxide (PEO). Herein, we fabricated ASSB structures that employed polyoxanorbornene-based bottlebrush polymers with PEO side chains as interlayers between the cathode and the electrolyte layer. This polymer exhibits semi-crystallinity and showcases high ionic conductivity (~0.63 mS cm-1) at room temperature due to the presence of the polyoxanorbornene backbone, which acts as an additional ion conductive agent alongside the PEO side chain, thus overcoming typical conductivity issues associated with using PEO-based materials. The resultant ASSB composed of the highly conductive polymer (HCP) interlayer demonstrates outstanding electrochemical performance including an improved specific capacity, rate performance, and cycling stability at room temperature, compared to the PEO interlayer. We will disclose data both describing the functional materials used as well as the performance of the test cells that were assembled.

MnO2, in its many phases, is abundant, non-flammable, non-toxic, reliable, made with abundant materials using simple manufacturing methods, and can have a high theoretical capacity for some phases (up to 617 mAh g(-1)). Here we have investigated the sensitivity of the performance ofbirnessite-produced in situ-to the presence of Bi2O3, depth-of-discharge, electrolyte salt type, and relative electrolyte volume. We prepared cathodes composed of 45 wt% MnO2, 22.5 wt% Bi2O3, and 22.5 wt% carbon additives, and compared cycling stability in two electrolytes-6.6 M KOH (27 wt%) and 6.6 M NaOH (21 wt%), and two types of 3-electrode test fixtures (flooded beaker or electrolyte-lean T-cell). Our results showed that birnessite can be synthesized electrochemically in NaOH, and cycling the cathode in NaOH improves its stability when compared to cycling in KOH. We tested the cathode in electrolyte-lean environments and found a drastic improvement in cycling stability in NaOH. The cathode exhibited higher initial capacity in lean amounts of KOH, but capacity retention plummeted after the first 20 cycles. In contrast, the cathode in NaOH delivered 65% of the theoretical capacity for over 400 cycles.

P2-phased layered oxide materials have been extensively studied as cathode material for sodium-ion batteries due to their high capacities and ionic conductivities, making them promising for large-scale applications. Additionally, manganese-based compounds, with their low cost and high capacity, have attracted significant attention in recent years. However, challenges remain regarding durability issues and related structural instability caused by the Jahn-Teller effect induced by Mn3+ ions formed during the cycling process in these materials, which causes manganese dissolution during use. In this study, we introduce a cathode composition of Na0.8Mn0.75Fe0.2Al0.05O2 and show that bismuth doping enhances the structural stability of the cathode material during electrochemical cycling. Electrodes with varying levels of bismuth doping were compared in half-cell configurations; material with 1% bismuth doping demonstrated outstanding stability, retaining 95.8% capacity after 200 cycles at a 0.2 C rate through the full potential range. dQ/dV analysis shows that bismuth doping effectively suppresses the excess Mn redox, which could otherwise deteriorate the cathode structure. As a proof of concept, Bi-doped materials were implemented in full cells paired with hard carbon that exhibited much better stability than those without bismuth doping. Lastly, the moisture and air stability of the bismuth-doped electrode were tested, demonstrating good stability.

Understanding the side reactions occurring inside lithium-ion cells remain a significant challenge, presenting opportunities for innovation. In this context, we developed a coupled 1H NMR (nuclear magnetic resonance) and dQ/dV (differential capacity) analysis method aimed at enhancing our understanding of these reactions during the formation cycle. Using deuterated acetonitrile as an extraction solvent, we measured the relative consumption of electrolyte components inside different electrolyte, including in 1.2M LiPF6 EC:EMC 3:7 2% VC and 1.2M LiPF6 EC:EMC 3:7 2% VC + 1% DTD electrolytes at different voltage. Our NMR observations were subsequently compared with electrochemical data to better understand and validate the results. These findings offer valuable insights into lithium-ion cell dynamics and mark a significant step towards the advancement of diagnostic techniques.

The increasing demand for hybrid electric vehicles (HEVs) necessitates batteries capable of higher discharge rates. This study focuses on the design of cathode pore structures in lithium-ion batteries, aiming to enhance bulk ion transport and thereby achieving higher spatial energy density at higher discharge rates, a critical requirement for hybrid EVs. We report here novel cathode pore space designs using well understood NCM 811 high energy density cathode material to address this need. These designs include a double layer structure with varying porosity, a femto-second laser etched directional pore structure, and how different electrolyte interacts with each of these systems. These tailored structures are hypothesized to facilitate improved ion transport, reducing local stress, and thus contributing to enhanced battery performance and extended battery lifespan. To validate our designs, we employed micrometer-scale X-ray computed tomography (CT) and pore network modelling for structural characterization, quantifying the pore structure mathematically. The performance of these cathodes was evaluated using a suite of electrochemical techniques, including cyclic voltammetry and Electrochemical Impedance Spectroscopy (EIS), which reveals their impact on cell level performance. Our findings contribute to the ongoing efforts to optimize lithium-ion battery technology for hybrid EVs, offering insights into the potential of tailored cathode structures to improve battery performance. Further research is needed to refine these designs and assess their scalability and feasibility for commercial applications.

Garnet-type Li6.4La3Zr1.4Ta0.6O7 (LLZTO) is regarded as a highly competitive next-generation solid-state electrolyte for all-solid-state lithium batteries owing to reliable safety, a wide electrochemical operation window of 0-6 V versus Li+/Li, and a superior stability against Li metal. Nevertheless, insufficient interface contacts caused by pores, along with Li dendrite growth at these voids and grain boundary regions, have hindered their commercial application. Herein, we suggest a method to produce high-quality LLZTO using LiAlO2 (LAO) as a chemical additive that leads to an improved microstructure with larger grain size (similar to 25 mu m), a high relative density (similar to 96%), lower porosity (similar to 3.7%), and continuous secondary phases in grain boundary regions. This improved structure results in (i) improved Li-ion conductivity and enhanced interfacial resistance between Li metal and LLZTO by a denser structure with fewer pores and (ii) suppression of Li dendrite penetration in the electrolyte by secondary phases in grain boundary regions.

Rechargeable batteries that can operate at elevated temperatures (>70 degrees C) with high energy density are long-awaited for industrial applications including mining, grid stabilization, naval, aerospace, and medical devices. However, the safety, cycle life, energy density, and cost of the available high-temperature battery technologies remain an obstacle primarily owing to the limited electrolyte options available. We introduce a flame-retardant electrolyte that can enable stable battery cycling at 100 degrees C by incorporating triacetin into the electrolyte system. Triacetin has excellent chemical stability with lithium metal, and conventional cathode materials can effectively reduce parasitic reactions and promises a good battery performance at elevated temperatures. Our findings reveal that Li-metal half-cells can be made that have high energy density, high Coulombic efficiency, and good cycle life with triacetin-based electrolytes and three different cathode chemistries. Moreover, the nail penetration test in a commercial-scale pouch battery using this new electrolyte demonstrated suppressed heat generation when the cell was damaged and excellent safety when using the triacetin-based electrolyte.

Poly(ethylene oxide) (PEO) is a very popular polymer-based solid electrolyte material with relatively high ionic conductivity and dielectric constant 1 . However, many previous works mentioned that it could not be used in high voltage cells for its low oxidation potential (~3.9V vs. Li/Li+) 2 . However, only a handful of prior investigations evaluated the stability of the PEO-based solid-state electrolyte considering the contribution of the cathode surface chemistry to electrolyte oxidation and decomposition. Since most of the previous research exploring high voltage cathodes with PEO used LiCoO 2 , it could be possible the other cathode compositions will erode the PEO-based solid electrolyte in different and less extreme ways. Our work revisits the high voltage electrochemical stability of PEO-based solid state-electrolyte materials. Potentiodynamic and galvanostatic tests were performed in test cells using PEO electrolyte layers with either LiNi x Mn y Co z O 2 or LiCoO 2 cathode materials. We found that the high voltage instability of PEO-based solid-state cells is profoundly affected by the instability of the cathode material used. Specifically, the LiCoO 2 electrodes were observed to undergo an irreversible oxidation process where they shattered into small pieces, which then led to a rapid irreversible loss in capacity. In contrast, we found that the PEO-based solid-state electrolytes could be stably cycled with high-nickel content cathodes stably at a voltage up to 4.5V vs. Li/Li+ over many cycles with minimal capacity deterioration. K. Chrissopoulou, K. S. Andrikopoulos, S. Fotiadou, S. Bollas, C. Karageorgaki, D. Christofilos, G. A. Voyiatzis, and S. H. Anastasiadis, 44 , 9710–9722 (2011). J. Qiu, X. Liu, R. Chen, Q. Li, Y. Wang, P. Chen, L. Gan, S.-J. Lee, D. Nordlund, Y. Liu, X. Yu, X. Bai, H. Li, and L. Chen, Adv. Funct. Mater. , 30 , 1909392 (2020).

This study explores the relationships between material quench rate during processing and the resulting structural and electrochemical properties of Li[Ni0.25 Li0.167 Mn0.583 ]O2 . Samples of this lithium-rich material are prepared with highly contrasting postfiring cooling methods: a rapid water emersion quench or closed-door oven cooling. The contrasting approaches result in samples with different structural, chemical, and electrochemical behaviors; after cycling the rapidly quenched material yields greater capacity, greater stability, and initially lower, but more stable voltages than the slower cooled samples. Through the use of scanning tunneling electron microscopy, X-Ray Diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) it is demonstrated that rapidly quenched powders are more structurally uniform and chemically homogenous before cycling. By comparing these precycling sample to postcycling samples, it is then examined how this increased structural uniformity and chemical homogeneity leads to the superior electrochemical properties of the rapidly quenched samples.