Lithium-ion Battery Cathode Research Articles

Stable surface lattice for prolonged cycle life of single-crystal lithium-rich layered oxide cathodes

Lithium-rich layered oxides (LLOs) have garnered significant attention due to their outstanding capacity. However, the severe capacity fading resulting from lattice deterioration initiated at the surface constrains the further advancement of LLOs. Here, we present a method to stabilize the surface lattice to enhance the capacity stability of LLOs. Specifically, we have engineered a nanometer-thin Gd-doped NiO rock-salt epitaxial layer on the surface of single-crystal LLOs, along with an atomic-level thickness LiGdO2coating layer. The dual-nanolayer protection strategy has successfully stabilized the surface structure of LLOs and suppressed electrode–electrolyte interface side reactions. As a result, the modified sample achieves a capacity retention rate of 93.4% after 500 cycles at 1C and 94.2% after 200 cycles at 0.2C. Our study underscores the importance of surface structure in achieving high cyclic stability in LLOs and provides an important approach for designing stable lithium-ion battery cathode materials.

Glutamate Leaching of Spent Lithium-Ion Battery Cathode in Weak Acidic-Neutral Condition: New Insight on Kinetics and Dissolution Mechanism

ABSTRACT Organic acid leaching receives less attention than inorganic acids for Li-ion battery recycling process at the industrial scale due to the high consumption rate of the acids as leaching reagents. This paper reports an effective leaching of cobalt (Co) and lithium (Li) from spent battery cathode using low concentration of monosodium glutamate as lixiviants. More than 95% of Co and Li could be dissolved at leaching conditions MSG 0.1 M (18 g/L), pH 5, sodium sulfite 0.5 M as reductant, pulp density 20 g/L, room temperature and leaching time 6 h. Increasing the temperature to 80°C sped up the leaching process, where maximum recovery could be attained within 1 h. pH played a major role in the leaching efficiency (effective range pH 4–6). pH lower than 4 led to neutral and cationic glutamate species, which were ineffective in attracting cobalt ion. pH higher than 6 initiated the surface passivation by Co(OH)2. In the absence of a passivation layer, cobalt dissolution mechanism followed the chemical reaction-controlled model, while in the presence of the layer, the mechanism switched to diffusion through product layer. Kinetic studies demonstrated that aside from pH, the formation of passivation layer was hypothetically regulated by adjusting the other leaching parameters. Aside from the observation on kinetic study, the proposed leaching mechanism was supported by characterization (particle size analysis, SEM-EDS, FT-IR) results.

Effective upcycling of NMC 111 to NMC 622 cathodes by hydrothermal relithiation and Ni-enriching annealing

It is imperative that a sustainable approach to the recycling of lithium-ion batteries (LIBs)—in particular the spent NMC cathodes—which reach their end-of-life (EOL) is realized as 11 million metric tonnes are expected to reach EOL by 2030. The current recycling processes based on pyrometallurgy and hydrometallurgy are not fully sustainable options as they recover only the value metals. By contrast direct recycling that aims in regenerating EOL LIB cathodes without breaking down the active compound’s crystal structure offers the most sustainable option. In this paper the direct recycling of NMC cathodes is investigated in combination with their upcycling. Upcycling is going to be in growing demand since the first generation NMC 111 cathode chemistries evolve to higher energy/nickel-rich formulations. In this work, the baseline is established for direct recycling of low and high nickel NMC cathodes by analyzing the three key steps of chemical delithiation of pristine NMC cathode material, hydrothermal relithiation (4M LiOH for 4 h at 220 °C), and annealing (4 h at 850 °C) in order to set the ground for investigating the upcycling of NMC 111 to NMC 622. Upcycling is affected via the co-addition of pre-calculated excess NiSO4 and Li2CO3 salts during annealing, following the hydrothermal relithiation step. Use of NiSO4 that is commonly used as p-CAM provides a lower cost alternative to Ni(OH)2 as Ni source. Characterization revealed the upcycled material to have been endowed with the typical α-NaFeO2 layered structure and have surface morphology and composition similar to pristine NMC material. The upcycled NMC 622 cathode yielded good cycling stability (91.5% retention after 100 cycles) and >99% Coulombic efficiency albeit with certain polarization loss justifying further optimization studies.

Synthesis and characterization of core–shell high-nickel cobalt-free layered LiNi0.95Mg0.02Al0.03O2@Li2ZrO3 cathode for high-performance lithium ion batteries

High-nickel cobalt-free layered cathode is regarded as a highly potential cathode material for the next generation lithium ion batteries (LIBs) because of its high energy density, low cost and environmentally benign. However, the poor cycle performance caused by its intrinsic unstable structure and chemo-mechanical instability frustrates its practical applications. Herein, we have developed a new core–shell high-nickel cobalt-free layered LiNi0.95Mg0.02Al0.03O2@Li2ZrO3 (LZO-NMA9523) cathode for high-performance LIBs. The Li2ZrO3 coating layer firstly helps to suppress and reduce the degree of Li+/Ni2+ cation mixing during the material preparation process. In addition, the Li2ZrO3 coating layer can not only accommodate the volume variations and enhance the electricity of the active materials, but also effectively inhibit the harmful irreversible phase transition during the charging/discharging process, thus greatly stabilizing the structure of the high-nickel cobalt-free cathode. As an advanced cathode for LIBs, the LZO-NMA9523 exhibits an excellent reversible capacity of 146.9 mAh g−1 after 100 cycles at 0.5 C with capacity retention of about 80%. This study provides a possible high-nickel cobalt-free layered cathode material for the next generation LIBs.

Application metal oxide cathode materials for lithium ion batteries

The popularity of portable electronic devices has boosted the speedy advancement of devices for storing electrical energy. At the same time, the development of electric vehicles urgently requires lithium batteries to have higher power density and performance. The strong points of lithium ion battery are environmental friendliness, also specific capacity of high level. Lithium cathode material is one of the key factors affecting battery performance. The requirements for positive electrode materials are good safety, good service life, and less self-discharge. Among all cathode materials, metal oxide cathode material is the most potential types, which comes from a wide range of sources and has rich production experience. In this paper, four kinds of lithium metal oxide cathode materials including lithium cobaltate, lithium nickelate, lithium manganate and ternary composite oxide cathode material were analyzed, and discussed the performance of lithium metal oxide cathode materials in practical applications, where further pointed out the existing problems of metal oxide cathode materials and put forward several directions for future improvement to improve the performance of lithium ion battery cathode materials in the future development and production process.

Conversion of Lithium Chloride into Lithium Hydroxide Using a Two-Step Solvent Extraction Process in an Agitated Kühni Column

A significant consequence of the green transition is the growing demand of lithium-ion batteries (LIBs), as they are essential for electrical vehicles. In turn, the demand for the raw materials that are needed to produce LIBs is increasing. A common LIB cathode type for electrical cars is lithium nickel manganese cobalt oxide (NMC). Since cobalt is currently considered as a critical raw material, nickel-rich NMC cathodes are now designed with lower cobalt contents. The synthesis of these new NMC types requires LiOH instead of Li2CO3, which was used for Co-richer NMC materials in the past. Most production routes of LiOH start from Li2CO3 or Li2SO4. However, LiCl could also be a potential precursor for LiOH, as it could be obtained from various lithium sources. A two-step solvent extraction process (SX) was developed for direct conversion of LiCl into LiOH, using a phenol (butylhydroxytoluene or BHT) and a mixture of quaternary ammonium chlorides (Aliquat 336) in an aliphatic diluent (Shellsol D70) as the solvent. The SX process was validated in counter-current mode using a rotary agitated Kühni extraction column. The use of a column instead of mixer-settlers reduced the CO2 uptake by the final product (LiOH), which prevented the partial conversion of LiOH to Li2CO3. A total of 75 L of LiCl feed solution was processed in the Kühni column to obtain a solution of LiOH with a final purity of more than 99.95%, at a yield of 96%.Graphical

Electropolymerization of Donor-Acceptor Conjugated Polymer for Efficient Dual-Ion Storage.

Rationally designed organic redox-active materials have attracted numerous interests due to their excellent electrochemical performance and reasonable sustainability. However, they often suffer from poor cycling stability, intrinsic low operating potential, and poor rate performance. Herein, a novel Donor-Acceptor (D-A) bipolar polymer with n-type pyrene-4,5,9,10-tetraone unit storing Li cations and p-type carbazole unit which attracts anions and provides polymerization sites is employed as a cathode for lithium-ion batteries through in situ electropolymerization. The multiple redox reactions and boosted kinetics by the D-A structure lead to excellent electrochemical performance of a high discharge capacity of 202mA h g-1 at 200mA g-1, impressive working potential (2.87 and 4.15 V), an outstanding rate capability of 119mA h g-1 at 10A g-1 and a noteworthy energy density up to 554Whkg-1. This strategy has significant implications for the molecule design of bipolar organic cathode for high cycling stability and high energy density.

Enhancing compatibility between LiNi0.8Co0.1Mn0.1O2 and LiPF6-based electrolyte via bis(trimethylsilyl)oxalate additive

LiNi0.8Co0.1Mn0.1O2 (NCM811)-layered oxide has a high discharge capacity and is considered as an alternative cathode for next-generation high-energy density lithium-ion batteries (LIBs). However, the corrosion of LiPF6-based electrolyte and the poor stability of the cathode solid electrolyte interface (CEI) film pose a threat to the cyclic stability of the battery. Herein, bis(trimethylsilyl)oxalate (DTMSO) is introduced as a novel multifunctional electrolyte additive to construct a stable CEI film and improve the high temperature tolerance of NCM811/Li cells. Results show that DTMSO can effectively scavenge HF resulted from trace water and high temperature, preventing the detrimental effects of HF on CEI film and NCM811 electrode material. More than that, DTMSO can react with LiPF6 to form conducive lithium tetrafluoro(oxalate)phosphate (LiTFOP) when undergoes the ordeal of high temperature (55 °C) for 24 h. The as-generated LiTFOP aids in the construction of a stable and conductive CEI film that is rich in LiF and LixPOyFz. Benefit from these characteristics, DTMSO additive enables effective protection of the electrode material and mitigates capacity decay in the battery, ultimately facilitating good cycling performance and improving ability to resist high temperature within a certain time. As a result, the capacity retention rate of the NCM811/Li cell after 100 cycles is increased from 67.8% to 85.6%, when the test condition is shelved at 55 °C for 24 h and then changed back to cycling at 25 °C. This work provides a viable strategy for the development of electrolytes compatible with nickel-rich cathode and is of great significance for the development of advanced LIBs.

Atomic-Scale Characterization of Microscale Battery Particles Enabled by a High-Throughput Focused Ion Beam Milling Technique.

The cathode materials in lithium-ion batteries (LIBs) require improvements to address issues such as surface degradation, short-circuiting, and the formation of dendrites. One such method for addressing these issues is using surface coatings. Coatings can be sought to improve the durability of cathode materials, but the characterization of the uniformity and stability of the coating is important to assess the performance and lifetime of these materials. For microscale particles, there are, however, challenges associated with characterizing their surface modifications by transmission electron microscopy (TEM) techniques due to the size of these particles. Often, techniques such as focused ion beam (FIB)-assisted lift-out can be used to prepare thin cross sections to enable TEM analysis, but these techniques are very time-consuming and have a relatively low throughput. The work outlined herein demonstrates a FIB technique with direct support of microscale cathode materials on a TEM grid that increases sample throughput and reduces the processing time by 60-80% (i.e., from >5 to ∼1.5 h). The demonstrated workflow incorporates an air-liquid particle assembly followed by direct particle transfer to a TEM grid, FIB milling, and subsequent TEM analysis, which was illustrated with lithium nickel cobalt aluminum oxide particles and lithium manganese nickel oxide particles. These TEM analyses included mapping the elemental composition of cross sections of the microscale particles using energy-dispersive X-ray spectroscopy. The methods developed in this study can be extended to high-throughput characterization of additional LIB cathode materials (e.g., new compositions, coating, end-of-life studies), as well as to other microparticles and their coatings as prepared for a variety of applications.

Stochastic reconstruction and performance prediction of cathode microstructures based on deep learning

The effective properties of lithium-ion battery (LIB) cathode are determined by both the volume fractions of constituents and the morphological features of microstructure. However, it is difficult to establish an accurate quantitative relationship between the macroscopic effective properties and microstructural features. Deep learning techniques, due to their exceptional nonlinear fitting capabilities, have been widely applied in various complex fields. Our study presents a generation scheme of numerous three-dimensional (3D) digital microstructures of cathode, using a deep convolutional neural network (CNN)-based stochastic reconstruction algorithm combining with the scanning electron microscope (SEM) images. The reconstructed samples are substituted with the corresponding finite element (FE) models, and the effective mechanical and electrochemical properties are assessed through the FE-based homogenization theory. Finally, the generated cathode samples and their effective properties are used to train the 3D CNN for performance prediction. This study demonstrates that the deep learning approaches can accurately and rapidly reconstruct the microstructure of cathode and predict their effective properties. Furthermore, the established framework can be extended to other heterogeneous materials.

Resource Recovery of Spent Lithium-Ion Battery Cathode Materials by a Supercritical Carbon Dioxide System.

The increasing global market size of high-energy storage devices due to the boom in electric vehicles and portable electronics has caused the battery industry to produce a lot of waste lithium-ion batteries. The liberation and de-agglomeration of cathode material are the necessary procedures to improve the recycling derived from spent lithium-ion batteries, as well as enabling the direct recycling pathway. In this study, the supercritical (SC) CO2 was innovatively adapted to enable the recycling of spent lithium-ion batteries (LIBs) based on facilitating the interaction with a binder and dimethyl sulfoxide (DMSO) co-solvent. The results show that the optimum experimental conditions to liberate the cathode particles are processing at a temperature of 70 °C and 80 bar pressure for a duration of 20 min. During the treatment, polyvinylidene fluoride (PVDF) was dissolved in the SC fluid system and collected in the dimethyl sulfoxide (DMSO), as detected by the Fourier Transform Infrared Spectrometer (FTIR). The liberation yield of the cathode from the current collector reaches 96.7% under optimal conditions and thus, the cathode particles are dispersed into smaller fragments. Afterwards, PVDF can be precipitated and reused. In addition, there is no hydrogen fluoride (HF) gas emission due to binder decomposition in the suggested process. The proposed SC-CO2 and co-solvent system effectively separate the PVDF from Li-ion battery electrodes. Thus, this approach is promising as an alternative pre-treatment method due to its efficiency, relatively low energy consumption, and environmental benign features.

Recovery of Ni-Co-Mn Oxides from End-of-Life Lithium-Ion Batteries for the Application of a Negative Temperature Coefficient Sensor

This study demonstrates the current advancements in battery management systems (BMSs), emphasizing the need for precise temperature monitoring within battery packs to enhance safety and performance through efficient thermal management. The increased demand for lithium-ion batteries (LIBs) has driven the development of temperature sensors with improved accuracy and stability. In particular, Ni-Co-Mn-based spinel oxides are commonly used due to their stable negative temperature coefficient (NTC) behavior. However, challenges arise in manufacturing due to the high cost and uncertain supply of critical cathode components (e.g., Co, Ni, and Mn) for LIBs. This research focuses on developing spinel-type (Ni0.6Co0.4Mn2)O4 using recycled Ni-Co-Mn oxides obtained from end-of-life (EOL) LIBs, demonstrating temperature resistance behavior suitable for temperature sensing. The oxides are prepared through hydrometallurgy, oxalate synthesis, and post-heat treatment. Successful integration into spinel-type NTC thermistors suggests broader applications in various industrial fields. A systematic investigation into the synthesis and characterization of recovered Ni-Co-Mn oxides from EOL LIB cathode materials (Li(Ni0.33Co0.33Mn0.33)O2) is presented for NTC thermistor application. Thermogravimetric analysis-derivative thermogravimetry (TGA-DTG) identifies the optimal post-heat treatment temperature. The X-ray diffraction (XRD) patterns confirm a cubic spinel structure of the Ni-Co-Mn oxides, supported by scanning electron microscope (SEM) images showing a uniform microstructure. Also, energy dispersive X-ray spectroscopy (EDS) mapping confirms homogeneous element distribution. Recovered oxide pellets from the sintering process exhibit a single spinel structure, with X-ray photoelectron spectroscopy (XPS) analysis revealing changes in the valence states for Ni and Mn. Resistivity measurements demonstrate semiconductive behavior, which shows a B value (3376.92 K) suitable for NTC thermistor applications. This study contributes valuable insights to black powder recycling from EOL LIBs and its potential in temperature-sensitive electronic devices.

Constructing oxygen-deficient shell on Li-rich cathodes by spark plasma sintering for high-performance lithium-ion batteries

Lithium-rich layered oxides (LROs) are considered as promising cathodes in building next-generation lithium-ion batteries (LIBs) with superior charge-discharge capacity. Nevertheless, LROs are confronted with irreversible oxygen loss accompanied with surface-to-bulk degradation upon cycling. To inhibit the oxygen release and to increase the lifespan of LROs, we report on an innovative strategy to rapidly construct an ultrathin oxygen-deficient shell layer covering the surface of LROs’ particles via a sparking plasma sintering (SPS) technique. It is demonstrated that the inner structure of the LROs’ particles is maintained, whereas the surface of the particles forms a thin shell (∼5 nm) consisting of a considerable amount of oxygen vacancies. Benefitting from the existence of an oxygen-deficient shell, the cathode activation is facilitated and the oxygen loss is suppressed, leading to enhanced capacity and prominent cyclability under long cycling. The modified LRO exhibits outstanding electrochemical performance, delivering a maximum capacity of 187.67 mAh g−1 and a capacity retention of 95.71% after 200 cycles at 250 mA g−1. Our work evidences that SPS is a fast and effective approach to construct oxygen-deficient shell on LRO cathodes for high-performance LIBs.

Boosting both electronic and ionic conductivities via incorporation of molybdenum for LiFe0.5Mn0.5PO4 cathode in lithium-ion batteries

As the EV and ESS markets expand, there is a growing interest in LiFexMn1-xPO4 (LFMP) cathode materials amidst the increasing demand for LIBs. The LFMP cathode material is cost-effective and structurally stable; however, it has the drawback of low conductivity. Therefore, the development of an LFMP cathode material with high ionic/electronic conductivity is essential for high-stability and high-C-rate LIB applications. We propose a carbon-coated LFMP cathode material with Mo placed at the Fe and Mn sites. The samples were synthesized using a solvothermal method. Mo contributes to enhanced Li-ion diffusion and charge transfer rates. The XRD Rietveld refinement results showed elongated Li–O bonds within the Mo-doped LFMP/C, which accelerated the Li+ ion diffusion. Through SEM, TEM–EDS mapping, and XPS analysis we have confirmed the properties and morphology of the material. The electrochemical evaluation of the material was conducted using galvanostatic charge-discharge, CV, and EIS methods. Based on these tests, Mo incorporation not only increased the capacity but also enhanced the rate performance, reduced the voltage polarization, and improved the lithium-ion diffusion coefficient. Based on the 3.7 V additional plateau, which is attributed to the sluggish kinetics of Mn3+, Mo6+ played a role in enhancing the kinetic behavior of Mn3+. Low-temperature performance tests demonstrated that the Mo-doped samples exhibited high energy density, cycle retention, and superior ionic conductivity. In summary, an appropriate amount of Mo doping is effective for improving the electrochemical performance of LFMP, making it a promising cathode material.

In-situ plasma assisted lithium-ion battery cathodes to catalytically pyrolyze lignin for H2-rich syngas production

In-situ plasma assisted lithium-ion battery cathodes catalysis was investigated to pyrolyze lignin to H2-rich syngas, oil and char. The effects of temperature, cathode to lignin ratio and plasma current on syngas production were investigated by using the typical ternary cathode NCM111 (LiNi1/3Co1/3Mn1/3O2) as catalyst and adopting dielectric barrier discharge mode. Response surface methodology based on BOX-BEHNKEN design was used to analyze the significance and interactions of process factors on the syngas yield. The conditions of 837℃, 10.4 %, and 185 mA for obtaining high-yield syngas (22.58 %) were more stringent; thereinto, from high to low, the intensity of factors on the yield was temperature, plasma current, and cathode ratio. Furthermore, different cathodes (non-cathode, NCM811 (LiNi4/5Co1/10Mn1/10O2), LCO (LiCoO2), and LMO (LiMn2O4)) were applied to decouple the catalytic effects of three metals in the NCM111. NCM111 enhanced both lignin gasification and carbonization by reducing condensable components, and NCM811 further improved gasification, but LCO and LMO had weaker gasification ability. NCM111 increased H2 volume fraction from 22.35 % to 67.31 %, NCM811 elevated the micro-discharge performance, promoting the hydrogasification reactions between energetic H species and char to produce more CH4, while LCO and LMO tended to produce the CO-rich syngas. Besides, in-situ plasma and its synergy with cathodes inhibited the formation of heavy aromatics and produced some high-value bio-oils rich in light aromatics, in which NCM111 achieved 92.30 % selectivity towards MAHs. High Ni ratio was beneficial for improving the char porosity, and the chars obtained by using NCM811 had a surface area of 409.29 m2/g, and a pore volume of 0.401 cm3/g. Comparably, the degree of catalytic lignin gasification for preparing H2-rich syngas could be ranked as Ni > Co > Mn in the ternary cathode.

The Role of Surface Free Energy in Binder Distribution and Adhesion Strength of Aqueously Processed LiNi0.5Mn1.5O4 Cathodes

This study identifies the critical aspects of binder distribution and mechanical integrity in aqueously processed LNMO cathodes, employing a comprehensive approach involving surface characterization techniques, adhesion strength testing, and electrochemical characterization. The investigation includes the use of the Washburn and Sessile Drop methods for surface free energy analysis, revealing key insights into the interfacial free energy of adhesion between cathode constituents. The results explain the formation of carbon-binder-domains and their impact on adhesion strength, with a particular focus on the conductive additives’ (CA) surface area. The study demonstrates the effectiveness of reducing CA surface area and employing alternative conductive additives, such as vapor-grown carbon fibers (VGCF), in improving adhesion strength and mitigating capacity fade attributed to delamination during cycling. Furthermore, the research emphasizes the role of heat treatment beyond the melting point of the polyvinylidene fluoride (PVDF) latex binder, showcasing its influence on wetting and enhancing mechanical integrity. The presented methodology provides a valuable tool for predicting and optimizing binder distribution, offering insights into improving the overall performance and reliability of aqueously processed cathodes for advanced lithium-ion batteries.

Li-doped transition metal high-entropy oxides (Li/TM-HEOs) as Li-Ion batteries cathodes: a first report on capacity fading and cycling stability

High-Entropy Oxides (HEOs) have gained significant attention for their wide range of compositions and potential applications across various sectors, including rechargeable batteries. This study explores the characterization of two distinct HEO systems as potential cathode materials for Lithium-ion batteries (LIBs). A series of rock salt structured HEOs with varying Li loadings (16Li/RS-HEO, 25Li/RS-HEO, 33Li/RS-HEO, and 41Li/RS-HEO) and a spinel-structured HEO with 16 mol% of Li loading (16Li/SP-HEO) were firstly synthesized through co-precipitation. Electrochemical analyses via cyclic voltammetry revealed stark differences in the behavior of these structures. The Li/SP-HEO sample displayed broad and strongly irreversible hysteresis cycles, while the Li/RS-HEO series manifested thin, narrow hysteresis cycles with single oxidation peaks between 0.5 V and 0.7 V. As the lithium content increases in the RS-HEO system, the cycling stability of the cell decreases, most likely due to the reduced ratio of transition metal cations to lithium ions. Although there was a noticeable decrease in capacity under higher current rates, the higher lithium loadings positively impact the cell capacity, albeit with notable capacity fading under higher current rates. Li-doped rock salt structured high entropy materials show potential for LIB cathodes in terms of high specific capacities; the observed stability issues at medium and high current densities indicate a rapid electrode degradation.

Recent Progress and Synthetic Methods for Single-crystalline Cathode in Lithium-ion Batteries

Ni-rich layered transition metal oxides have been regarded as the most feasible way for achieving high energy density of lithium-ion batteries. Conventional Ni-rich cathodes are composed of spherical secondary particles, consisting of numerous primary particles. Unfortunately, the grain boundaries in the polycrystalline structure are vulnerable to the pulverization, leading to microcracks during cycling. The newly exposed surface from the microcrack can induce undesirable side reactions with the electrolyte, which severely deteriorates the battery performance. On the other hand, single-crystalline Ni-rich cathodes have gained significant attention for industrial applications due to their robust mechanical strength, resulting from the elimination of grain boundaries. The improved mechanical properties of single-crystalline cathodes effectively mitigate the interfacial side reactions, thereby attaining superior structural, thermal, and electrochemical performance. Herein, we have introduced various synthetic methods of the single-crystalline cathode, encompassing not only high-temperature sintering and the molten-salt method for the Ni-rich cathode but also the other strategies for different single-crystalline cathode materials. This review aims to provide a comprehensive understanding of single-crystalline cathode synthesis, with implications for the development of high-performance cathode materials.

Bio-aromatics synthesis via catalytic pyrolysis of cellulose with lithium-ion battery cathodes and modified HZSM-5 coupled in-situ plasma mode

This work proposed a novel method based on in-situ plasma mode to synthetize bio-aromatics from cellulose co-pyrolyzed with lithium-ion battery cathodes and tandem catalyzed by modified HZSM-5. Ni and Ti modified HZSM-5 were compared in the catalytic pyrolysis of cellulose without cathode conditions, and then cellulose was co-pyrolyzed with cathodes (LCO, LMO and LNCM). The results showed that modified-zeolites improved the upgrading of pyrolysis products, producing more refined bio-oils, and Ti-modified version was superior, while cellulose co-pyrolyzed with cathodes decreased the residual char and catalyst deposits to increase refined bio-oil. When using LNCM, the refined bio-oil yield reached 38.80%, attributing to the catalytic effect of cathodes, enhanced thermal conductivity, and micro lithium-ion battery effect. The application of cathodes and modified zeolites enhanced the conversion of furans, greatly elevating the MAHs selectivity; herein, Ni-modified version increased PAHs. After using LNCM, the selectivity of MAHs reached 77.67% (mainly C8 hydrocarbons), C10 and above hydrocarbons were suppressed, which was possibly attributed to enhanced gas-phase reactions. Abundant free radical reactions and higher cracking capability enabled coking to initially occur inside, and using LNCM decreased the catalyst coke content by approximately 80%. Co-pyrolysis with cathodes caused the surface coke to transform from filament-like to amorphous.

Research on Pretreatment Process for Recycling Lithium-Ion Battery Cathode Materials

Research on Pretreatment Process for Recycling Lithium-Ion Battery Cathode Materials