Manganese-based Cathode Materials Research Articles

Enhancing electrochemical performance of lithium-rich manganese-based cathode materials through lithium sulfate coating

Enhancing electrochemical performance of lithium-rich manganese-based cathode materials through lithium sulfate coating

Synergistic effect of interlayered doping and surface modification to improve the performance of Li-rich manganese-based cathode materials

Li-rich manganese-based oxides (LRMOs) with high energy density have been intensively studied, but their practical use as cathode materials for lithium-ion batteries is still impeded by the shortcomings such as low initial coulombic efficiency, voltage decay and poor rate capability. To address these issues, element Nb is selected to bulk dope and simultaneously surface modify the hierarchical Li1.20Mn0.54Co0.13Ni0.13O2 spheres in this work. Synergistic effect of Nb doping and surface modification on the crystalline structure and electrochemical performance of the resultant LRMOs is characterized in detail. The results suggest that Nb5+ ions are doped into the interlayer sites within the crystals while the LiMn2O4 and LiNb3O8 double layers are coated on the primary nanoparticles. The galvanostatic charge-discharge measurements reveal that the optimal LRMO-Nb2 sample can deliver the capacities of 286 and 167 mAh g−1 at the rates of 0.1 C and 5 C, respectively, and retains a capacity of 191 mAh g−1 at 1 C rate after 200 cycles. Ex-situ XRD patterns prove that the layered structure is strongly pillared by the interlayer-doped Nb5+ during the delithiation/lithiation processes. Especially, some lithium vacancies formed around Nb5+ ions can accelerate the diffusion of Li+ ions, which was proved by DFT calculations and experimental results. Our research demonstrates that cooperating of the interlayered doping of Nb5+ with surface coating of LiNb3O8 layer can improve rate capability and cyclability of the resultant LRMOs significantly.

Construction of rod-like micro/nano structure and its effects on the electrochemical energy storage performance of lithium-rich manganese-based cathode material

Construction of rod-like micro/nano structure and its effects on the electrochemical energy storage performance of lithium-rich manganese-based cathode material

Enhancing aqueous zinc-ion batteries: The role of copper-ion-doped Mn3O4 as cathode material

It is widely recognized that manganese-based cathode materials are the most prospective cathode energy storage materials among zinc ion batteries. While rapid capacity decay and structural instability are the main hindrance in the rapid advancement of Manganese based materials. It has been established that ion doping is an accurate lever to enhance the stability of the structure and cycling performance of manganese-based materials. In this work, copper ions were selected as doping of Mn3O4 to mitigate obstacle of H+/Zn2+ extraction/insertion by expanding the lattice spacing of Mn3O4. The results show that Cu2+ doping results in a significant improvement in the properties of Mn3O4 (CMO). After 600 cycles at a current density of 1 A g−1, the initial capacity retention rate of Mn3O4 without doping is only 35.4 %, while the CMO achieves a capacity retention rate of 98.9 % (capacity retention of 166 mAh g−1). In addition, the CMO obtains a high specific capacity of 360 mAh g−1 at 0.1 A g−1. The significant difference in electrochemical properties between CMO and Mn3O4 indicates that Cu2+ doping improves the energy storage capacity of the cathode material.

Bifunctional low molecular weight polyacrylic acid as aqueous binder and coating agent enables high performance LiMn2O4 cathode for lithium-ion batteries

LiMn2O4 is considered to be a promising cathode material for lithium-ion batteries due to its decent energy density, low price and environmental benignity. However, the problems of Mn dissolution, migration and deposition during the cycle, seriously affect its lifespan, especially at high temperature. In this study, we developed a strategy by which we killed two birds with one stone. A low molecular weight polyacrylic acid (PAA) mixed with sodium carboxymethyl cellulose (CMC) is applied as binder and coating agent for cathode particles at the same time. The conventional and environmental unfriendly polyvinylidene difluoride (PVDF)-N-methylpyrrolidone (NMP) system is replaced by the cheap and green aqueous binder with improved adhesive effect. Furthermore, the binder-based surface coating layer not only alleviates the side reaction between the electrolyte and the cathode particles, but also chelates the dissolved Mn2+ by the large amount of carboxyl groups in PAA molecules and so prevents the following migration and deposition of Mn2+. In the button half-cell with low molecular weight PAA based binder, the capacity retention reaches 94.1 % after 1000 cycles at room temperature and 92.0 % after 200 cycles at 60 degrees centigrade. Meanwhile, 18650-type cylindrical cells were prepared with this binder, which shows a great high temperature storage performance. After the cell was held at 60 degrees centigrade for 25 days at full charged state, the internal resistance increased by only 1.25mΩ, the voltage decreased by only 0.1 V, the residual capacity retention and recovery capacity retention reaches 85.6 % and 92.2 %. This work shows the great potential of the aqueous binder in dealing with the problem of Mn dissolution during the cycling of manganese-based cathode materials for lithium-ion batteries.

Inducing Mn defects within MnTiO3 cathode for aqueous zinc-ion batteries

Layered manganese-based cathode materials are considered as one of the promising cathodes benefit from inherent low manufacturing cost, non-toxic and high safety in aqueous zinc-ion batteries (AZIBs). However, the sluggish reaction kinetics within layered cathodes is inevitable due to the poor electrical/ionic conductivity. Herein, MnTiO3 is reported as a new cathode material for AZIBs and in-situ induced Mn-defect within MnTiO3 during the first charging is desirable to improve the reaction kinetics to a great extent. Additionally, DFT calculations further demonstrate that MnTiO3 with manganese defects exhibits a uniform charge distribution at the defect sites, enhancing the attraction towards H+ and Zn2+ ions. Furthermore, it performs good cycling stability which can obtain 115 mA h g−1 even at 400 mA g−1 after 450 cycles and the discharge capacity reaches up to 233.8 mAh/g at 100 mA g−1 when Mn-defect MnTiO3 was employed as the cathode. This research could provide a new method for the development and mechanism research of cathode materials for AZIBs.

Review on Layered Manganese-Based Metal Oxides Cathode Materials for Potassium-Ion Batteries: From Preparation to Modification.

Potassium-ion battery is rich in resources and cheap in price, in the era of lithium-ion battery commercialization, potassium-ion battery is the most likely to replace it. Based on the classification and summary of electrode materials for potassium-ion batteries, this paper focuses on the introduction of manganese-based oxide KxMnO2. The layered KxMnO2 has a large layer spacing and can be embedded with large size potassium-ions. This paper focuses on the preparation and doping of manganese-based cathode materials for potassium-ion batteries, summarizes the main challenges of KxMnO2-based cathode materials in the current stage of research and further looks into its future development direction.

Performance improvement of Li-rich Mn-based materials with the submicron-sized single-crystal morphology and cationic doping

Lithium-rich manganese-based cathode materials (LRMCs) can be regarded as one of the most potential cathode materials for the next-generation high-energy Li-ion batteries due to the extra oxygen redox, which can greatly increase the actual output energy density of LRMCs. Nevertheless, the structure degradation and inevitable loss of oxygen will be triggered by the irreversible oxygen redox, which will cause a significant decline in cyclic performance and limited initial Coulombic efficiency, thus restricting their industrial applicability. Herein, the LRMCs with the submicron-sized single-crystal morphology and sodium doping are prepared by molten salt treatment with NaCl. On one hand, the submicron-sized single-crystal cathode effectively reduces the diffusion path for Li+ due to the smaller particle dimensions. On the other hand, Na+ doping expands the Li slab spacing, promoting the transport of Li+. The results show that the as-prepared material can purposefully alleviate oxygen release, improve structure stability, and increase the Li+ diffusion rate for the pristine LRMCs. Moreover, the as-prepared material in this study exhibits a higher reversible capacity of 282.8 mAh g−1 at 0.1 C and displays good cyclic performance, retaining a capacity rate of 80.9% after 200 cycles at 1 C. Therefore, this study offers a potential exploration for designing LRMCs with high energy density and excellent cyclic performance, which are achieved through building submicron-sized single-crystal morphology and introducing cationic doping.

Modification of lithium-rich manganese-based cathode materials by continuous coating formed by surface treatment of sodium dodecyl sulfate to improve electrochemical performance

With the development of new energy devices, the demand for electrode materials with high energy density (> 400 Wh/kg) is increasing day by day. Lithium-rich manganese-based cathode materials (LRMC) which meet the requirements are considered one of the most promising materials for the next generation of lithium-ion batteries, and have attracted wide attention. However, LRMC still faces some key scientific problems that need to be addressed, such as interface side reactions, poor rate performance, rapid voltage and capacity attenuation, and low first coulomb efficiency. The continuous Na2SO4-coated lithium-rich manganese-based cathode material Li1.2Ni0.13Co0.13Mn0.54O2 (S-LRMC) was synthesized using sodium dodecyl sulfate (SDS). SDS is composed of hydrophobic aliphatic hydrocarbon groups and hydrophilic sulfate carboxyl groups, so it can form a micelle-like coating on the surface of LRMC materials in aqueous solution. The uniform Na2SO4 coating formed after calcination can effectively inhibit the side reaction between electrode material and electrolyte and reduce the dissolution of transition metal ions. As a result, capacity retention, rate performance and discharge specific capacity are improved. After 100 cycles at 1 C, the specific discharge capacity of 4% S-LRMC is 187.8 mAh g−1 (LRMC is 138.3 mAh g−1), and the capacity retention is 87.35%. Even at a high current density of 5 C, the material still has a specific discharge capacity of 143.6 mAh g−1, which proves that the electrochemical performance of the material is excellent. Therefore, this study provides a new solution for improving the structural stability and electrochemical performance of lithium ion batteries.

PO43--doped layer @ spinel @ rGO sandwich-structured lithium-rich manganese-based cathode material with enhancing rate capability and cycle stability for Li-ion battery

The Li-rich Mn-based cathode (LRM) material faces challenges like low initial coulombic efficiency (ICE) and reduced capacity retention, which limit their commercial viability in high energy density lithium-ion batteries (LIBs). These challenges primarily arise from the irreversible migration of transition metal ions (TMn+) and the escape of lattice oxygen. Herein, this study proposes a novel approach to enhance Li-rich cathodes by implementing a PO43--doped layer @ spinel @ rGO sandwich structure, which effectively addresses the aforementioned challenges. Through the synergistic effects of PO43- doping and rGO surface modification, the modified samples demonstrate remarkable electrochemical properties. These include an impressive initial coulombic efficiency (ICE) of 87.54%, and a superior capacity of 187.12 mAhg−1 and 149.44 mAhg−1 at 25°C and 45°C, respectively, following 200 cycles at 1 C. Additionally, they exhibit an outstanding rate capability of 82.3 mAhg−1 at 10 C and a minimal voltage decrease of 0.504 V after 200 cycles. The synergetic strategy presented in this work serves as an inspiring source for the exploration of high energy density and long-cycle cathode materials.

Achieving CoAl2O4@Li1.2Ni0.13Co0.13Mn0.54O2 with Long Cyclic and High-Rate Performance via Citric Acid Combustion Method

Lithium-rich manganese-based cathode materials (LNCM) have high specific capacities and operating voltages. However, they also have intractable deficiencies such as low capacity retention and unsatisfactory rate capability. Herein, CoAl2O4 with spinel structure and chemically stable is adopted to decorate the surface of LNCM to modify the cyclic and high-rate performance of final product. 3CoAl2O4@LNCM synthesized by self combustion of citric acid shows the best electrochemical properties such as lower voltage drop (4.7 mV per cycle) and higher capacity retention of 81.33% (1 C) after 100 cycles, which is exceed to bare LNCM (7.7 mV per cycle, 47.65%). Besides, the charge transfer resistance R ct of the modified sample is lower, and its lithium ion diffusion coefficient D Li + is higher. Consequently, 3CoAl2O4@LNCM is able to demonstrate high rate performance, whereby a capacity retention of 65.84% (5 C) is achieved after 100 cycles. The improved electrochemical properties of 3CoAl2O4@LNCM because of the 3D diffusion channel of CoAl2O4 benefits lithium ion diffusion; and the chemical stability of CoAl2O4 enhances the corrosion resistance of LNCM bulk to the electrolyte. As such, this results in the suppression of TM ion dissolution, and the enhancement of cyclic stability and initial coulomb efficiency.

Li-rich Mn-based Li1.2Mn0.54 Ni0.13Co0.13O2 with carbothermal reduction coated spinel heterogeneous layer to enhance the electrochemical performance

High-capacity Li-rich Manganese-based cathode materials (LMCs) have been considered ideal cathodes for Li-ion batteries (LIBs) because of the Li2MnO3 phase with anion activity and the LiTMO2 phase (TM: transition metal) with cation activity. However, the LMCs suffer from oxygen and Li irreversible loss in the cycles, which results in voltage decline, capacity attenuation, and a low initial Coulomb efficiency (ICE). Herein, we report co-precipitation synthesis of Li1.2Mn0.54Ni0.13 Co0.13O2 (LMNCO) cathodes by citric acid pretreatment, followed by carbothermal reduction to obtain a heterogeneous spinel layer of LMNCO surface. Organic acid undergoes carbonation and thermal reduction during annealing in an Ar atmosphere, contributing to the heterogeneous spinel layer reconstruction and the Mn reduction. The heterogeneous spinel layer facilitates Li-ion transportation by providing 3D Li diffusion channels and avoids bulk-phase corrosion by the electrolyte, as a buffer layer. At 0.1C, the surface-modified LMNCO cathodes render discharge capacity reaches up to 303.7 mAh g−1, and the ICE is 85.6%. Furthermore, at a 1C current, the discharge capacity is found to be 248.4 mAh g−1, and after 100 cycles, the capacity retention is 84.6%. These consequences demonstrate that the heterogeneous spinel layer significantly improves the capacity, ICE, and cyclic stability of the surface-modified LMNCO cathodes. The current study presents a successful modification to enhance the LMCs electrochemical performance, which is of utmost significance for practical applications.

The function of phenylphosphonic acid on diversifying the property of manganese dioxide applied in the aqueous zinc-ion battery

The manganese-based rechargeable aqueous zinc-ion batteries have garnered significant attention due to their advantageous properties including high theoretical specific capacity, low cost, simple preparation, and environmental friendliness. The properties of the manganese-based cathode material depend strongly on its crystalline structure, the particle size, the morphology, and the functional elements, which plays a crucial role in further determining the electrochemical performance of the battery system. In this study, we disclose a distinctive function of phenylphosphonic acid (H2PP) in diversifying the intrinsic properties and electrochemical performance of manganese dioxide (MnO2) as the cathode material in the aqueous zinc-ion battery. By adding H2PP during preparation, the growth of MnO2 can be induced to form γ-MnO2 and α-MnO2, depending on the amount of H2PP used, in contrast to β-MnO2 prepared without the addition of H2PP. Moreover, the morphology of the cathode material can also be differentiated. Additionally, MnO2 can be functionalized by P-based groups from H2PP. By incorporating 0.5 % H2PP, a porous γ-MnO2 with a large specific surface area and high ionic conductivity is formed, which results in the battery exhibiting a high specific capacity of 225 mAh/g at the current density of 1 A/g, along with decent cycling performance.

钾离子电池锰基正极材料研究进展

钾离子电池锰基正极材料研究进展

Addressing Challenges and Enhancing Performance of Manganese-based Cathode Materials in Aqueous Zinc-Ion Batteries

Addressing Challenges and Enhancing Performance of Manganese-based Cathode Materials in Aqueous Zinc-Ion Batteries

Synergistic enhancement of Li-rich manganese-based cathode materials through single crystallization and in-situ spinel coating

Lithium-rich manganese-based cathode (LRM) materials are considered the most promising cathode for the next-generation high-energy-density Li-ion batteries due to their high specific discharge capacity. However, the current mainstream LRM materials exhibit a polycrystalline morphology, and the degradation of this morphology during extended cycling exacerbates structural distortions, leading to poor cycle stability. Herein, a spinel phase encapsulated single-crystal LRM material with a particle size of about 500 nm is prepared through a simple molten-salt assistant solid-state synthesis method utilizing traditional polycrystalline LRM precursor, followed by boric acid treatment. Combined with various characterizations, the surface coating layer of obtained single-crystal LRM materials is identified as spinel Li4Mn5O12 with a thickness of about 5 nm, which effectively enhances Li+ diffusion kinetics. Benefited from the collaborative strategy of single crystallization and spinel coating which strength Li+ conduction and suppresses particle cracking, the single-crystal LRM materials achieve a specific discharge capacity of 296.3 mAh g−1 at 0.1 C (1 C = 250 mA g−1), yielding a capacity retention of 97.4% after 300 cycles at 1 C. This study offers a universal and easy industrial scale-up approach for developing single-crystal LRM cathode materials with long cycling stability, which promotes the commercial utilization of single-crystal LRM cathode.

A New Approach in Surface Modification of Manganese Based Cathode Materials for Enhanced Performance in Zinc Aqueous Batteries

With the growing demand for sustainable and environmentally friendly energy storage solutions, zinc-aqueous batteries have emerged as promising alternatives to conventional lithium-ion batteries. Among the various cathode materials studied for zinc-aqueous batteries, manganese dioxide (MnO2) has garnered significant attention due to its high theoretical capacity, abundance, and non-toxic nature. However, the intrinsic limitations of MnO2, including low electrical conductivity and sluggish kinetics, have hindered its practical application. To address the aforementioned limitations, we present a new approach in surface modification of KxMnO2 cathode with improved electrochemical performance for zinc-aqueous batteries.In this study, the KxMnO2 cathode material’s surface has been fluorinated, that enhances capacity retention of the material and effectively improves the overall electrochemical performance. Structural and morphological characterizations of the surface modified KxMnO2 were performed using operando X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM), X-ray Absorption Near Edge Spectroscopy (XANES) and thermogravimetric analysis (TGA). Furthermore, X-ray photoelectron spectroscopy (XPS) and Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS) confirmed the successful fluorination of the material surface.Electrochemical tests, including cyclic voltammetry (CV), galvanostatic charge-discharge (GCD), and electrochemical impedance spectroscopy (EIS), were conducted to evaluate the performance of the surface fluorinated KxMnO2 cathode in comparison to pristine KxMnO2. The results demonstrated a remarkable improvement in the specific capacity, rate capability, and cycling stability of the modified cathode. The improvement of electrochemical performance can be attributed to the effect of the fluorine element, which alleviates the structural degradation of KxMnO2 during cycling. The improved electrochemical performance of the KxMnO2 cathode paves the way for the development of high-performance, cost-effective, and environmentally friendly zinc-aqueous batteries.

Effects of Synthesis Conditions of Na0.44MnO2 Precursor on the Electrochemical Performance of Reduced Li2MnO3 Cathode Materials for Lithium-Ion Batteries.

Li2MnO3 nanobelts have been synthesized via the molten salt method that used the Na0.44MnO2 nanobelts as both the manganese source and precursor template in LiNO3-LiCl eutectic molten salt. The electrochemical properties of Li2MnO3 reduced via a low-temperature reduction process as cathode materials for lithium-ion batteries have been measured and compared. Particularly investigated in this work are the effects of the synthesis conditions, such as reaction temperature, molten salt contents, and reaction time on the morphology and particle size of the synthesized Na0.44MnO2 precursor. Through repeated synthesis characterizations of the Na0.44MnO2 precursor, and comparing the electrochemical properties of the reduced Li2MnO3 nanobelts, the optimum conditions for the best electrochemical performance of the reduced Li2MnO3 are determined to be a molten salt reaction temperature of 850 °C and a molten salt amount of 25 g. When charge-discharged at 0.1 C (1 C = 200 mAh g-1) with a voltage window between 2.0 and 4.8 V, the reduced Li2MnO3 synthesized with reaction temperature of Na0.44MnO2 precursor at 850 °C and molten salt amounts of 25 g exhibits the best rate performance and cycling performance. This work develops a new strategy to prepare manganese-based cathode materials with special morphology.

Improving the electrochemical performance of Li-rich manganese-based cathode materials by surface treatment with triethylamine

Li-rich manganese-based cathode material is expected to be extremely promising for next-generation lithium-ion batteries due to its high specific capacity derived from additional anion redox behavior and low cost of the main element manganese. However, the irreversible release of lattice oxygen results in poor structural stability and inferior electrochemical performances, such as low initial Coulomb efficiency, irreversible capacity decay and serious voltage decay, which limits its commercialization. Herein, a simple strategy to improve the structural stability and electrochemical performances by one-step treatment with triethylamine (TEA) at moderate temperature is reported. TEA was used as a surface treatment reagent to prepare the modified Li-rich manganese-based cathode materials with oxygen vacancies and local structural distortion on the surface. The presence of surface distortion layer and oxygen vacancies inhibits irreversible oxygen release. The result exhibits that initial Coulomb efficiency, rate performance and initial discharge specific capacities are improved. After 100 cycles at a current density of 1 C, the specific capacity of the surface-treated material is 204.3 mAh g-1 (172.6 mAh g-1 for the pristine material), with a capacity retention of 81.26%. Even at a high current density of 10 C, the discharge specific capacity of 139.4 mAh g-1 is still achieved, demonstrating the excellent electrochemical performance. This study provides a simple and effective strategy for constructing special surface structures on Li-rich manganese-based materials to achieve high performance.

Opportunities and Challenges of Layered Lithium-Rich Manganese-Based Cathode Materials for High Energy Density Lithium-Ion Batteries

Opportunities and Challenges of Layered Lithium-Rich Manganese-Based Cathode Materials for High Energy Density Lithium-Ion Batteries