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At least 163 records · Page 9

High-Performance Low-Cobalt Cathode Materials for Li-ion Batteries

The layer-structured Li[Ni x Co y Mn 1-x-y ]O 2 (NCM) cathode materials have been the best choice for increasing electric vehicle driving distance per charge. The high Ni layered oxide represents successfully commercialized NCM cathodes (such as NCM622 and NCA) in lithium-ion batteries (LIBs) for EV applications due to their high energy density and acceptable cycling stability. However, the price of cobalt, the key element within LIBs for stability, has nearly tripled over the past few years due to increased demand from the cell phone industry. As mentioned in the DOE Funding Opportunity Announcement, the current materials shortage will also cause speculation for a future global shortage. Therefore, to meet the requirement and sustainability of the next-generation long-range and low-cost EVs, developing cathode materials with low-Co content to achieve higher energy density and lower cost is both essential and urgent. The overarching objective of this work is to develop stabilized NCM cathode materials with low Co content (namely LiNi x Co y Mn 1-x-y O 2 , y ≤ 0.04) to meet DOE’s goal of reducing Co loading below 50 mg Wh -1 while maintaining energy density greater than 600 Wh kg -1 based on cathode material. Via various dopings and coatings scalable methods, we explored and enhanced the cycling performance of low-cobalt cathodes. The final obtained NCM cathodes paired with graphite anode aim to deliver batteries with a high initial specific energy density of over 240 Wh kg -1 and a low capacity fading rate of less than 20% in 1000 cycles under a C/3 discharge rate. To accomplish this goal, a multidisciplinary team with several co-investigators has been formed from three organizations: The Pennsylvania State University (PSU), Oak Ridge National Laboratory (ORNL), and Pacific Northwest National Laboratory (PNNL). The PI and co-investigators are Dr. Donghai Wang (PI) from PSU with expertise in the synthesis of nanostructured materials and manipulation of interfacial properties of electrochemically active materials, Dr. Jagjit Nanda, with substantial knowledge of and expertise in state-of-the-art cathodes from ORNL, Dr. Chao-Yang Wang with significant experience in advanced cell design and fabrication and cell diagnostics from PSU, and Dr. Chongmin Wang with world-wide known expertise of advance atomic scale characterization of electrode materials from PNNL. Furthermore, this project will leverage and synergistically work with the current DOE-funded programs on battery materials at PSU and ORNL and electrode materials characterization at PNNL. During this funded period, we have accomplished milestones stated as follows: • Scale up production of LiFePO 4 (LFP) coated NCM811 with a production of 300g/batch. Fifteen (≥2 Ah) pouch cells with LFP-coated NCM811 cathode are delivered. Self-evaluated pouch cells in PSU show superior over 80% capacity retention performance even after 1500 cycles at C/3 rate. • Various cations (Al, Ti, Zr, and Mo) substitute cobalt in low-cobalt partially and Co-free cathodes. Their effects on crystal structure and electrochemical behavior are explored. • Phosphate compounds as coating materials represent promising surface protection precursors for low-cobalt cathode materials. Therefore, several metal phosphates were selected for improving the NMC cycling performance and are regarded as effective approaches for a scalable and practical surface protection method. • Production of NCM92, where Nickel content is 92% among transition metals, is scaled up from synthesis to coating and heat treatment procedures. Fifteen 2.7Ah pouch cells with Ti-doped NCM92 cathodes and industrial graphite anode are delivered to Idaho National Lab for testing.

25 ENERGY STORAGE↗

Cost‐Effective Layered Oxide – Olivine Blend Cathodes for High‐Rate Pulse Power Lithium‐Ion Batteries

Abstract Sustainability and supply‐chain concerns require lithium‐ion batteries (LIBs) free from critical minerals, such as nickel and cobalt. While recent advances provide encouraging signs that cobalt can be removed, the question remains how much Ni can be removed from Co‐free layered oxide cathodes before sacrificing critical performance metrics. This study highlights the effect of reducing Ni by benchmarking several Co‐free cathodes with decreasing Ni content. Keeping the energy density the same by increasing the charge voltage, cathodes below 80% Ni content exhibit worsened capacity fade due to increasing oxygen release and electrolyte decomposition. Charge transfer and diffusion kinetics are also hindered with increasing Mn content and exacerbated by resistive surface phases formed at high voltages, rendering lower‐Ni, Co‐free cathodes less competitive than high‐Ni cathodes for high energy and power applications. It is demonstrated blending layered oxide with olivine as an effective alternative to deliver energy density and cycling stability comparable to lower‐Ni cathodes with moderate charging voltages. Blending with 30 wt% olivine LiMn 0.5 Fe 0.5 PO 4 (LMFP) virtually eliminates the diffusion limitation of layered oxides at low state‐of‐charge, with enhanced pulse power characteristics rivaling the high‐Ni counterparts. Cathode blending can further reduce the overall Ni content and cost without the performance limitations of lower‐Ni, Co‐free cathodes.

Lee, Steven↗

Valence Effects of Fe Impurity for Recovered LiNi 0.6 Co 0.2 Mn 0.2 O 2 Cathode Materials

Iron impurities are generally included in the obtained leaching liquor solution during the hydrometallurgical recycling method of spent lithium-ion batteries (LIBs) due to the usage of iron in battery casings and machinery parts of recycling equipment, which would definitely affect the physical and electrochemical features of the recovered active materials. In this paper, the effects of iron impurity with different valence states (Fe 2+ and Fe 3+ ) and gradient concentrations (0.2, 1.0, and 5.0 at. %) for the obtained LiNi 0.6 Co 0.2 Mn 0.2 O 2 (NCM622) cathodes are fully studied. It is found that Fe3+ impurity could easily lower the tap density and average size of NCM622 particles and even introduce some impurity phases in the NCM622 structure at high concentration (5.0 at. %), leading to much lower specific capacity, worse rate capability, and cycling performance of the Fe 3+ -based NCM622 cathode. On contrast, with certain concentrations of Fe 2+ impurity (0.2 and 1.0 at. %), the NCM622 cathode material exhibits comparable and much better electrochemical properties compared with the virgin NCM622 materials. Based on these results, the valence of Fe impurity should be considered and controlled as well as its concentration during the recycling process design for spent LIBs.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Impact of surface coating on electrochemical and thermal behaviors of a Li-rich Li 1.2 Ni 0.16 Mn 0.56 Co 0.08 O 2 cathode

Lithium-rich layered oxide materials are considered as potential cathode materials for future high-performance lithium-ion batteries (LIBs) owing to their high operating voltage and relatively high specific capacity. However, perceptible issues such as poor rate performance, poor capacity retention, and voltage degradation during cycling need to be improved before the successful commercialization of the material. In this report, zirconia coated Li 1.2 Ni 0.16 Mn 0.56 Co 0.08 O 2 2 = 1.0, 1.5 and 2.0 wt%) materials are synthesized using a sol–gel assisted ball milling approach. A comparison of structural, morphological and electrochemical properties is examined to elucidate the promising role of ZrO 2 coating on the performance of the NMC cathode. A uniform and homogeneous ZrO 2 coating is observed on the surface of NMC particles as evident by TEM elemental mapping images. The ZrO 2 coated NMCs exhibit significantly improved electrochemical performance at a higher C-rate as compared to pristine material. 1.5% ZrO 2 coated NMC demonstrates better cycling stability (95% capacity retention) than pristine NMC (77% capacity retention) after 50 cycles. All ZrO 2 coated NMC materials demonstrated improved thermal stability compared to pristine material. The difference in onset temperature of 2 wt% ZrO 2 coated and pristine NMC is 20 °C. The improved electrochemical performance of ZrO 2 coated NMC can be attributed to the stabilization of its surface structure due to the presence of ZrO 2 .

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Ionic liquid-enhanced recycling of lithium-ion battery black mass via heavy liquid centrifugal separation

Direct recycling of lithium-ion batteries (LIBs) is of great significance to supply chain security and environmental protection by restoring spent battery materials to their original purpose without destroying their chemical structure. One of the key processes for direct recycling is to separate valuable anode and cathode active materials from black mass. This study evaluates ionic liquid-enhanced Heavy Liquid Centrifugal Separation (HLCS) as an efficient method for separating LIB black mass into its constituent anode and cathode materials. The optimized HLCS process achieved a separation efficiency of over 95%, yielding a graphite-rich upper layer and an NMC-rich lower layer. Characterization by thermogravimetric analysis (TGA), X-ray diffraction (XRD), and inductively coupled plasma-optical emission spectroscopy (ICP-OES) confirmed the purity and structural integrity of the recovered fractions. The addition of N-methyl-2-pyrrolidone and ionic liquid 1-ethyl-3-methylimidazolium bromide decoupled entangled particles, while subsequent treatment of the anode layer with 1-(2,3-dihydroxypropyl)-3-methylimidazolium chloride further enhanced separation purity. The recycled graphite exhibited comparable battery performance to pristine graphite. These results demonstrate HLCS as a promising LIB recycling strategy, advancing sustainable battery manufacturing.

Adigun, Babafemi [Univ. of Tennessee, Knoxville, T↗

Full Concentration Gradient-Tailored Li-Rich Layered Oxides for High-Energy Lithium-Ion Batteries

Lithium-rich layered oxides (LLOs) are prospective cathode materials for next-generation lithium-ion batteries (LIBs), but severe voltage decay and energy attenuation with cycling still hinder their practical applications. In this study, a series of full concentration gradient-tailored agglomerated-sphere LLOs are designed with linearly decreasing Mn and linearly increasing Ni and Co from the particle center to the surface. The gradient-tailored LLOs exhibit noticeably reduced voltage decay, enhanced rate performance, improved cycle stability, and thermal stability. Without any material modifications or electrolyte optimizations, the gradient-tailored LLO with medium-slope shows the best electrochemical performance, with a very low average voltage decay of 0.8 mV per cycle as well as a capacity retention of 88.4% within 200 cycles at 200 mA g –1 . These excellent findings are due to spinel structure suppression, electrochemical stress optimization, and Jahn-Teller effect inhibition. Further investigation shows that the gradient-tailored LLO reduces the thermal release percentage by as much as about 41% when the battery is charged to 4.4 V. This study provides an effective method to suppress the voltage decay of LLOs for further practical utilization in LIBs and also puts forward a bulk-structure design strategy to prepare better electrode materials for different rechargeable batteries.

36 MATERIALS SCIENCE↗

Resolving Chemical and Spatial Heterogeneities at Complex Electrochemical Interfaces in Li-Ion Batteries

The high specific capacities of Ni-rich transition metal oxides have garnered immense interest for improving the energy density of Li-ion batteries (LIBs). Despite the potential of these materials, Ni-rich cathodes suffer from interfacial instabilities that lead to crystallographic rearrangement of the active material surface as well as the formation of a cathode electrolyte interphase (CEI) layer on the composite during electrochemical cycling. While changes in crystallographic structure can be detected with diffraction-based methods, probing the chemistry of the disordered, heterogeneous CEI layer is challenging. In this work, we use a combination of ex situ solid-state nuclear magnetic resonance (SSNMR) spectroscopy and X-ray photoemission electron microscopy (XPEEM) to provide chemical and spatial information, on the nanometer length scale, on the CEI deposited on LiNi 0.8 Mn 0.1 Co 0.1 O 2 (NMC811) composite cathode films. XPEEM elemental maps offer insight into the lateral arrangement of the electrolyte decomposition products that comprise the CEI and paramagnetic interactions (assessed with electron paramagnetic resonance (EPR) and relaxation measurements) in 13 C SSNMR provide information on the radial arrangement of the CEI from the NMC811 particles outward. Using this approach, here we find that LiF, Li 2 CO 3 , and carboxy-containing structures are directly appended to NMC811 active particles, whereas soluble species detected during in situ 1 H and 19 F solution NMR experiments (e.g., alkyl carbonates, HF, and vinyl compounds) are randomly deposited on the composite surface. We show that the combined approach of ex situ SSNMR and XPEEM, in conjunction with in situ solution NMR, allows spatially-resolved, molecular-level characterization of paramagnetic surfaces and new insights into electrolyte oxidation mechanisms in porous electrode films.

36 MATERIALS SCIENCE↗

Towards extreme fast charging of 4.6V LiCoO 2 via mitigating high-voltage kinetic hindrance

High-voltage LiCoO 2 (LCO) is an attractive cathode for ultra-high energy density lithium-ion batteries (LIBs) in the 3C markets. However, the sluggish lithium-ion diffusion at high voltage significantly hampers its rate capability. Herein, combining experiments with density functional theory (DFT) calculations, we demonstrate that the kinetic limitations can be mitigated by a facial Mg 2+ +Gd 3+ co-doping method. The as-prepared LCO shows significantly enhanced Li-ion diffusion mobility at high voltage, making more homogenous Li-ion de/intercalation at a high-rate charge/discharge process. The homogeneity enables the structural stability of LCO at a high-rate current density, inhibiting stress accumulation and irreversible phase transition. When used in combination with a Li metal anode, the doped LCO shows an extreme fast charging (XFC) capability, with a superior high capacity of 193.1 mAhg -1 even at the current density of 20C and high-rate capacity retention of 91.3% after 100 cycles at 5C. In conclusion, this work provides a new insight to prepare XFC high-voltage LCO cathode materials.

25 ENERGY STORAGE↗

Aqueous Ni-rich-cathode dispersions processed with phosphoric acid for lithium-ion batteries with ultra-thick electrodes

Lithium-ion battery (LIB) production can benefit both economically and environmentally from aqueous processing. Although these electrodes have the potential to surpass electrodes conventionally processed with N -methyl-2-pyrrolidone (NMP) in terms of performance, significant issues still exist with respect to ultra-thick cathodes ($\gg$4 mAh/cm 2 areal capacities). A major concern for these types of electrodes with high-nickel active material stems from lithium leaching from active material, which drives the pH of the dispersion in excess of 12 and subsequently corrodes the current collector interface. As this corrosion reaction proceeds, hydrogen generation at the interface creates bubbles which cause severe cracking in the dried electrode surface. When areal loadings are increased, this effect becomes more pronounced and is detrimental to both mechanical and electrochemical properties of these electrodes. In this work, a technique for mitigating corrosion at the current collector by adjusting the pH of the dispersion with the addition of phosphoric acid is investigated. Phosphoric acid was added in 0.5 wt% increments between 0.0 and 1.5 wt%, and effects on rheology, adhesion, corrosion, and electrochemical performance were investigated. A technique is reported for producing aqueous processed cathodes with areal loadings of 6–8 mAh/cm 2 with reduced surface cracking and superior high-rate discharge capacity (i.e. high-power performance) for this class of cathode loadings.

25 ENERGY STORAGE↗

Ultra-high efficient lithium recovery via terephthalic acid from spent lithium-ion batteries

The recovery of lithium from spent lithium-ion batteries (LIBs) is a critical step in advancing sustainability within the battery industry. Traditional lithium extraction methods from end-of-life LIBs predominantly rely on chemical leaching techniques. However, these methods often involve the excessive use of acids, leading to substantial environmental concerns. Additionally, their non-selective nature can compromise the purity of the recovered lithium salt. To achieve battery-grade purity, further purification and recovery processes are necessary. In this study, we introduce a universal and eco-friendly process for lithium recovery, employing terephthalic acid to selectively extract lithium prior to the recycling of other valuable metals. This innovative method achieves lithium recovery rates exceeding 98.53% from layered oxide cathodes and 98.53% from lithium iron phosphate cathodes, delivering an exceptional purity level of 99.95%. By demonstrating applicability across a variety of cathode materials, this approach establishes a universal, sustainable and efficient solution for LIB recycling. The high-purity lithium extraction enabled by this process supports the comprehensive utilization of valuable resources, contributing significantly to the development of a circular economy for battery materials.

Hou, Jiahui [Worcester Polytechnic Institute, MA (↗

A Self‐Healing Chemistry‐Enabled Organic Cathode for Sustainable and Stable Sodium‐Ion Batteries

Sodium‐on batteries (SIBs) are promising alternatives to lithium‐ion batteries (LIBs) because of the low cost, abundance, and high sustainability of sodium resources. Analogous to LIBs, the high‐capacity electrodes in SIBs always suffer from rapid capacity decay upon long‐term cycling due to the particle pulverization induced by a large volume change. Circumventing particle pulverization plays a critical role in developing high‐energy and long‐life SIBs. Herein, tetrahydroxy‐1,4‐benzoquinone disodium salt (TBDS) that can self‐heal the cracks by hydrogen bonding between hydroxyl group and carbonyl group is employed as a cathode for sustainable and stable SIBs. The self‐healing TBDS exhibits long cycle life of 1000 cycles with a high rate capability up to 2 A g −1 due to the fast Na‐ion diffusion reaction in the TBDS cathode. The intermolecular hydrogen bonding has been comprehensively characterized to understand the self‐healing mechanism. The hydrogen bonding‐enabled self‐healing organic materials are promising for developing high‐energy and long‐cycle‐life SIBs.

25 ENERGY STORAGE↗

DEVELOPMENT OF STABLE ANODE AND CATHODE MATERIALS FOR RECHARGEABLE BATTERIES

Batteries have been employed in a variety of applications, such as portable electronics, electric vehicles (EVs), and stationary energy storage to preserve energy from other renewable sources (like wind or solar energy). The ultimate goal is to develop high energy density, long life span, better safety, and low cost of the batteries. However, current commercialized batteries (like lead-acid, zinc-alkaline, lithium-ion batteries (LIBs)) could not fulfill all the demands of diversified applications. LIBs predominate the market because of their high energy density. To achieve a higher capacity of the cell, high-nickel layered (Ni > 90%) cathode materials are promising candidates since they compose high specific capacity and discharge voltage. In chapter 1, an introduction to cell energy density and the development of high-nickel layered cathode materials along with associated obstacles of poor cycling stability and thermal stability have been discussed. Associated works like doping or surface coating have also been mentioned in this section. In chapter 2, Al doping in high-nickel layered cathode materials to enhance the structural and thermal stability was introduced. Uniform incorporation of Al doping is achieved by mechanical fusion and calcination processes. The Al doping not only decreased the Li/Ni mixing ratio but also enhance the thermal resistance to oxygen evolution because of strong Al-O bonding, which leads to elevated electrochemical and thermal stability. In chapter 3, TiN is implemented as a Ti dopant for high-nickel layered cathode materials to improve the electrochemical performance in the LIBs. The Ti not only diffused within the bulk structure but also formed segregation on the surface, which improved the structural stability and led to better cycling performance. Although LIBs deliver high energy density, safety concerns of flammable organic electrolytes have not been resolved yet. Therefore, the aqueous rechargeable zinc-ion batteries (ZIB) have been praised for their safe, low-cost, eco-friendly stationary energy storage, which is considered as a complementary system to LIBs. In chapter 4, the mechanism, advantages, and challenges of ZIBs would be given and the strategies for solving the zinc metal anode issues have been discussed in this section. In chapter 5, a polymer coating method was reported to facilitate Zn deposition/ stripping by coordination with Zn2+ and prevented direct contact with aqueous electrolyte to block corrosion side-reactions. With this coating, a boost in a lifetime (up to 400 hours) and lower polarization under extremely high current conditions (10 mA cm-2) have been achieved in repeated Zn deposition/ stripping cycling.

25 ENERGY STORAGE↗

A Mg-Doped High-Nickel Layered Oxide Cathode Enabling Safer, High-Energy-Density Li-Ion Batteries

High-nickel layered oxide cathodes with a Ni content of > 90% show substantial potential for next-generation lithium-ion batteries (LIBs) due to their high capacity and lower cost. However, they are plagued by rapid capacity decay and poor thermal stability, which hamper their practical viability. Here we present Li 0.98 Mg 0.02 Ni 0.94 Co 0.06 O 2 (NC-Mg) with 2% Mg doping, aiming to provide a strategic guideline for solving the issues. The Mg 2+ ions occupy the lithium layer and are pro-posed to act as pillar ions, which substantially enhances the structural reversibility and reduces the anisotropic lattice distortion upon cycling, thereby greatly improving the electrochemical and thermal stability of NC-Mg compared to the undoped LiNi 0.94 Co 0.06 O 2 (NC). Specifically, NC-Mg delivers 214 mA h g -1 with a capacity retention of 80.1% after 500 cycles in pouch-type full cells, much higher than the retention of NC (56.3%). A discharge capacity of 158 mA h g -1 at 10C rate demonstrates its remarkable rate capability. Additionally, the Mg doping significantly elevates the exothermic peak tem-perature of NC-Mg to 211 °C, in sharp contrast to 177 °C for NC, highlighting the improved thermal stability of NC-Mg. Collectively, the superior performance of NC-Mg demonstrates a feasible alternative strategy for developing safer, high-energy-density LIBs.

25 ENERGY STORAGE↗

Direct Recycling R&D at the ReCell Center

The expected rapid growth in electric vehicle deployment will inevitably be followed by a corresponding rise in the supply of end-of-life vehicles and their lithium-ion batteries (LIBs). The batteries may be reused, but will eventually be spent and provide a potential domestic resource that can help supply materials for future battery production. However, commercial recycling processes depend on profits from recovery of cobalt, use of which is being reduced in new cathode chemistries. The U.S. Department of Energy, therefore, established the ReCell Center in early 2019 to develop robust LIB recycling technology that would be economical even for batteries that contain no cobalt. The central feature of the technology is recovery of the cathode material with its unique crystalline cathode morphology intact in order to retain its value and functionality. Other materials are recovered as well in order to maximize revenues and minimize waste-handling costs. Analysis and modeling serve to evaluate and compare process options so that we can identify those that will be most economical while still minimizing energy use and environmental impacts. This paper provides background and describes highlights of the center’s first 2 years of operation.

Gaines, Linda (ORCID:0000000237263387)↗

Multiphase, Multiscale Chemomechanics at Extreme Low Temperatures: Battery Electrodes for Operation in a Wide Temperature Range

Understanding the behavior of lithium-ion batteries (LIBs) under extreme conditions, for example, low temperature, is key to broad adoption of LIBs in various application scenarios. LIBs, poor performance at low temperatures is often attributed to the inferior lithium-ion transport in the electrolyte, which has motivated new electrolyte development as well as the battery preheating approach that is popular in electric vehicles. A significant irrevocable capacity loss, however, is not resolved by these measures nor well understood. Herein, multiphase, multiscale chemomechanical behaviors in composite LiNi x Mn y Co z O 2 (NMC, x + y + z = 1) cathodes at extremely low temperatures are systematically elucidated. The low-temperature storage of LIBs can result in irreversible structural damage in active electrodes, which can negatively impact the subsequent battery cycling performance at ambient temperature. Furthermore, beside developing electrolytes that have stable performance, designing batteries for use in a wide temperature range also calls for the development of electrode components that are structurally and morphologically robust when the cell is switched between different temperatures.

25 ENERGY STORAGE↗

Electrochemical-driven green recovery of lithium, graphite and cathode from lithium-ion batteries using water

The expected exponential increase in consumption of lithium-ion batteries (LIBs) would pose a unique challenge to the availability of near-critical resources like lithium and graphite in the upcoming decade. In this work, we present a lithium recovery process that utilizes a degradation mechanism, i.e., lithium plating, as a tool to concentrate metallic lithium at the anode/separator interface for convenient extraction at room temperature – using only water. Electrochemical characterization of fast charged (1–6 C) LIBs yielded a maximum capacity fade of 50% over ten cycles. The lithium plating was confirmed via voltage plateau analysis, coulombic efficiency, and DC resistance measurements. A maximum lithium plating condition was observed to exist between 4C and 5C, thereby limiting the energy consumption in the extraction process. Post-mortem film thickness measurement showed an incrementing film deposition with a maximum of 35 µm thickness. SEM and XPS analysis confirmed increasing concentration of a dense dendritic metallic lithium deposition on the anode/separator interface with C-rate. A green recovery process was adopted to extract the concentrated metallic lithium using distilled water. The lithium from the plated film, solid/electrolyte interface (SEI), electrolyte, anode, and cathode, was extracted as salts. A 37% improvement in lithium recoverability was achieved with fast charging under ambient conditions. XPS analysis showed ~92% of lithium yield with no residual lithium in the graphite. In addition, the battery-grade graphite was recovered with 97% purity after heat treatment of the washed anode film, and concentrated transition metals oxides in the cathode to 93% purity for convenient extraction.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Tunning the linkage of structure units to enable stable spinel-based cathode in the wide potential window

The low practical capacity (<140 mA h g –1 ) of spinel phase LiMn 2–x Ni x O 4 (0 < x < 1) excludes it from high energy density lithium ion batteries (LIBs) for powering electric vehicles. Extending the operating potential window from 3.0 to 4.8 V to 2.0–4.8 V can double the capacity, but result in fast capacity decay due to the drastic cubic-tetragonal phase transition below 3.0 V, induced by serious Jahn-Teller (J-T) distortion of structure units (Mn 3+ )O 6 octahedra. Herein, we propose a novel strategy to suppress J-T distortion by tuning the linkage of structure units MnO 6 octahedra. The original full-vertex-sharing LiO 4 tetrahedra around MnO 6 octahedra in spinel phase are partially replaced by edge-sharing LiO 6 octahedra, which relate Mn-O bonds along the dz 2 direction with those along the d xy plane, thus significantly mitigating J-T distortion and suppressing the phase transition when discharged to 2.0 V. Following this strategy, the prepared spinel-based cathode achieves a high reversible capacity of about 290 mA h g –1 and an energy density up to 957 W h kg –1 with improved cycling stability. Furthermore, this work finds a new opportunity for the traditional spinel cathode towards applications in high energy density LIBs in a low cost and sustainable manner.

25 ENERGY STORAGE↗

Life-cycle analysis of lithium chemical production in the United States

To achieve its ambitious national decarbonization goals, the United States has incentivized the domestic production of materials critical to decarbonization technologies, including lithium-ion batteries (LIBs). These materials include battery-grade lithium chemicals (Li-chemicals), for which the U.S. is encouraging domestic production from resources (sedimentary clays and low Li-content brines (LLCBs)) that differ substantially from conventional sources (Salar brines and spodumene ores). Here, we conduct the first-ever comparative life-cycle analysis of Li-chemical production from all alternative resources (in the U.S.) and conventional sources based on data from company literature for U.S.-related production efforts. Two energy sources (electricity and natural gas), four material inputs (HCl, NaOH, Na 2 CO 3 , and CaO), and process carbon emissions dominate the life-cycle impacts (≥90% share) of U.S.-based Li-chemical production. Comparatively, the life-cycle impacts of alternative sources-based Li-chemicals lie between those for Li-chemical production from Salar brines and from spodumene ores. At the battery level, the shift in Li-chemical sourcing causes a notable change in LIB's life-cycle impacts (by ~5–15%), independent of the cathode chemistry employed. Our study highlights the relevance of a decarbonized electric grid and the capture and sequestration of process carbon emissions generated during Li-chemical and upstream material production in decarbonizing Li-chemical production from alternative sources. Further decarbonization would necessitate using decarbonized material inputs and a shift away from natural gas towards renewable energy for alternative resource-based Li-chemical production processes.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗