Lithium Diffusion Research Articles

Mitigating Diffusion‐Induced Intragranular Cracking in Single‐Crystal LiNi0.5Mn1.5O4 via Extended Solid‐Solution Behavior

Single‐crystal cathodes have been investigated for their inherent resistance to intergranular cracking due to the absence of grain boundaries. However, these materials exhibit significant intergranular cracking, and the underlying mechanisms remain unclear. In this study, we examined the impact of extended solid‐solution reactions on mitigating crack formation in magnesium‐doped single‐crystal LiNi0.5Mn1.5O4 (Mg‐SC‐LNMO) cathodes. With Mg acting as a structural pillar, the overall volume change was reduced by nearly 50%, the two‐phase reaction was effectively suppressed, and the Li‐ion diffusion coefficient was doubled. Continuum modeling based on experimental observations demonstrates that Mg doping significantly reduces the internal stress induced by lithium diffusion, thereby preserving the mechanical integrity of single‐crystal LNMO. This improvement leads to enhanced electrochemical performance and durability. Our study provides new insights into mechanically robust single‐crystal cathodes and proposes a design strategy to improve the durability of next‐generation Li‐ion batteries.

Mitigating Diffusion-Induced Intragranular Cracking in Single-Crystal LiNi0.5Mn1.5O4 via Extended Solid-Solution Behavior.

Single-crystal cathodes have been investigated for their inherent resistance to intergranular cracking due to the absence of grain boundaries. However, these materials exhibit significant intergranular cracking, and the underlying mechanisms remain unclear. In this study, we examined the impact of extended solid-solution reactions on mitigating crack formation in magnesium-doped single-crystal LiNi0.5Mn1.5O4 (Mg-SC-LNMO) cathodes. With Mg acting as a structural pillar, the overall volume change was reduced by nearly 50%, the two-phase reaction was effectively suppressed, and the Li-ion diffusion coefficient was doubled. Continuum modeling based on experimental observations demonstrates that Mg doping significantly reduces the internal stress induced by lithium diffusion, thereby preserving the mechanical integrity of single-crystal LNMO. This improvement leads to enhanced electrochemical performance and durability. Our study provides new insights into mechanically robust single-crystal cathodes and proposes a design strategy to improve the durability of next-generation Li-ion batteries.

INSIGHTS INTO THE ELECTROCHEMICAL PROPERTIES OF GERMANIUM-COBALT-INDIUM NANOSTRUCTURES IN A WIDE TEMPERATURE RANGE

Germanium-cobalt-indium (Ge-Co-In) nanostructures are a promising material for negative electrodes of lithium-ion batteries aimed for arctic exploitation. Electrochemical impedance spectroscopy was used for a detailed study of the interaction of Ge-Co-In nanostructures with lithium in a temperature range from ‒35 to +20°C. The discharge capacity at temperatures of 20, 0, ‒10, ‒20, and ‒35°C amounted to 1400, 1228, 1040, 907, and 793 mAh g‒1, respectively. The impedance spectra measured at various lithiation degrees were found to differ but insignificantly whereas temperature variation resulted in notable changes in the spectra. A normalized charge transfer resistance for Ge-Co-In nanostructures was significantly (more than an order of magnitude) less than for Ge-In nanowires (obtained by the same method, but without the addition of cobalt salt into the electrolysis solution). It is this difference in charge transfer resistance that can explain the difference in the shapes of the impedance spectra for both objects. Also, in contrast to data for Ge-In nanowires, the dependences of the lithium diffusion coefficient in Ge-Co-In nanostructures on potential had a clearly defined minimum. The lithium diffusion coefficient in Ge-Co-In nanostructures slightly exceeded that in Ge-In nanowires, and the activation energy of lithium diffusion in Ge-Co-In nanostructures was marginally less than in Ge-In nanowires.

Revealing the lithium ion diffusion kinetics and cycling stability of rare earth doped LiFePO4/C cathodes

Revealing the lithium ion diffusion kinetics and cycling stability of rare earth doped LiFePO4/C cathodes

Uphill diffusion of lithium along phosphorus gradients in olivine from mafic layered intrusions

Uphill diffusion of lithium along phosphorus gradients in olivine from mafic layered intrusions

First-Principles Calculation of Lithium and Sodium Ion Diffusion in Crystalline Silicon Suboxide for Next-Generation Battery Anodes

First-Principles Calculation of Lithium and Sodium Ion Diffusion in Crystalline Silicon Suboxide for Next-Generation Battery Anodes

Unlocking Enhanced Redox Dynamics: The Power of a Bifunctional Catalytic Zinc Phosphide Interface in Full Cell and Pouch Lithium-Sulfur Batteries.

Lithium-sulfur (Li-S) batteries face significant challenges, such as polysulfide dissolution, sluggish reaction kinetics, and lithium anode corrosion, hindering their practical application. Herein, we report a highly effective approach using a zinc phosphide (ZnP2) bifunctional catalyst to address these issues. The ZnP2 catalyst effectively anchors lithium polysulfides (LiPSs), catalytically reactivates them, and enhances lithium-ion diffusion. Utilizing a ZnP2-modified separator in a Li-S half-cell achieves an impressive initial capacity of 1145.4 mAh g-1, retaining 954 mAh g-1 and 99.8% Coulombic efficiency after 100 cycles, compared to the pristine separator. The underlying reaction mechanisms are thoroughly investigated through post-mortem analyses and density functional theory (DFT) calculations. Moreover, a Li-S full cell with an E/S ratio of 10 μL mg-1 demonstrates stable cycling performance, achieving an initial capacity of 797.5 and 534 mAh g-1 after 100 cycles at 0.1C, with a negative-to-positive mass ratio of 3:1. Additionally, the real-world feasibility of lightweight and flexible Li-S pouch batteries with ZnP2-modified separators is explored, showing a stable performance over 100 cycles at 0.1C with 80% capacity retention. This engineered separator can be integrated with advanced sulfur cathodes to create high-energy-density, stable Li-S batteries for commercial applications.

Rational Design Strategy of Multicomponent Si/FeSeOx@N‐Doped Graphitic Carbon Hybrid Microspheres Intertwined with N‐Doped Carbon Nanotubes as Anodes for Ultra‐Stable Lithium‐Ion Batteries

Herein, an efficient synthesis approach is introduced for the fabrication of a hybrid anode consisting of porous microspheres with biphasic silicon (Si)‐amorphous iron selenite (Si/FeSeOx) nanocrystals enveloped within an N‐doped graphitic carbon (NGC) matrix and encased by well‐grown, highly intertwined N‐doped carbon nanotubes (CNTs) (Si/FeSeOx@NGC/N‐CNT). Si and FeSeOx serve as the active components, contributing to the overall discharge capacity of the hybrid anode. Additionally, FeSeOx not only enhances the structural integrity of the nanostructure by channelizing the drastic volume variation of Si, but also expedites the diffusion of lithium ions, thereby promoting kinetically favored redox reactions. The NGC matrix serves as the primary pathway for efficient electron transfer within the electrode, whereas the well‐grown N‐CNTs network acts as a secondary pathway for subsequent electron transfer to the current collector. The porous structure achieved via selective removal of amorphous carbon ensures the smooth diffusion of charged species by shortening the effective charge diffusion length and accommodating the substantial volume changes during cycling. Correspondingly, the Si/FeSeOx@NGC/N‐CNT anodes demonstrate significant enhancements in electrochemical performance, including one‐order higher diffusion coefficients (≈10−12 cm2 s−1), exceptional rate capability (till 30 A g−1), and extraordinary cycling stability at 0.5, 1.0, and 3.0 A g−1.

Revisiting the in-plane and in-channel diffusion of lithium ions in a solid-state electrolyte at room temperature through neural network-assisted molecular dynamics simulations.

Developing superionic conductor (SIC) materials offers a promising pathway to achieving high ionic conductivity in solid-state electrolytes (SSEs). The Li10GeP2S12 (LGPS) family has received significant attention due to its remarkable ionic conductivity among various SIC materials. Ab initio molecular dynamics (AIMD) simulations have been extensively used to explore the diffusion behavior of Li+ ions in Li10GeP2S12. These simulations indicate that Li+ ions diffuse rapidly along a one-dimensional (1D) chain direction, specifically along the c-axis, a process known as in-channel diffusion. In addition, these computational studies have identified additional diffusion pathways within the ab planes, referred to as in-plane diffusion. However, there are still notable limitations in the time scale associated with AIMD simulation techniques for studying the dynamic behavior of Li10GeP2S12 at room temperature. In this study, we trained a deep potential (DP) model for the LGPS system and performed a 300-nanosecond DeePMD simulation to investigate the diffusion behavior of Li10GeP2S12 at room temperature. The neural network (NN) assisted simulation showed that the framework structure of LGPS remained remarkably stable over the entire 300-nanosecond period. Following this, our investigation focused on the two-dimensional (2D) diffusion pathways within the ab plane (in-plane diffusion mechanism) and the 1D diffusion channel along the c-axis (in-channel diffusion mechanism). Upon analyzing the DeePMD simulation results, we identified two distinct pathways for in-plane Li+ diffusion within the ab plane: the Li-2 and Li-4 pathways. We determined the energy barriers for the two diffusion pathways to be 0.23 eV and 0.34 eV, respectively, in qualitative agreement with recent experimental and theoretical results. For the in-channel diffusion along the c-axis, our calculated energy barrier was approximately 0.083 eV, closely matching the previous one-particle potential (OPP) analysis. Our results confirm experimental and theoretical studies, indicating that lithium ions experience significantly less resistance when diffusing through the in-channel pathway compared to the in-plane migration mechanism. However, our findings suggest that despite having a higher energy barrier than the Li-4 pathway, the Li-2 pathway remains a viable option for in-plane lithium-ion migration.

AA-Stacked Hydrogen-Substituted Graphdiyne for Enhanced Lithium Storage.

Graphdiyne (GDY) has been considered a promising electrode materialfor application in electrochemical energy storage. However, studies on GDY featuring an ordered interlayer stacking are lacking, which is supposed to be another effective way to increase lithium binding sites and diffusion pathways. Herein, we synthesized a hydrogen-substituted GDY (HsGDY) with a highly-ordered AA-stacking structurevia a facile alcohol-thermal method. Such unique architecture enables a rapid lithium transfer through the well-organized pore channels and endows a stronger adsorption capability to lithium atom as compared to the arbitrarily-stacked mode. The resultant HsGDY exhibits a reversible capacity of 1040 mA h g-1 at 0.05 A g-1ranking among the most powerful GDY-based electrode materials, and an excellent rate performanceas well as a long-term cycling stability. The successful preparationof gram-level high-quality HsGDY products in batches implies thepotential for large-scale lithium-storage applications.

Adsorption of lithium, sodium, gallium, and sulfur atoms onto a GaS monolayer

Abstract Hexagonal gallium sulfide (GaS) monolayer is a very promising monochalcogenide for applications such as electronics, optoelectronics, and catalysts. The adsorption and the diffusion of lithium (Li), sodium (Na), gallium (Ga), and sulfur (S) atoms onto the 2 × 2-GaS hexagonal monolayer are investigated using density functional theory (DFT), along with atomic pseudopotentials. The values of the calculations for the adsorption energy show that the energetically most favorable site for the Li, Na, and Ga adsorbates is the H site, while the most energetically favorable site for the S adsorbate is the TS site. The values calculated for the adsorption energy at the energetically most favorable sites for the Li, Na, Ga, and S atomic adsorbates are −1.853 eV, −1.378 eV, −1.028 eV, and −1.525 eV, respectively. Analysis of the structural properties revealed that after the adsorption process, the GaS+ads system maintains its structure and geometry, since the lattice constants and the lGa-Ga, lGa-S, and lS-S bond lengths do not change significantly with respect to the pristine monolayer. The diffusion of Li, Na, Ga, and S atoms on the 2 × 2-GaS monolayer’s surface shows energy barriers of 28 meV, 40 meV, 72 meV, and 161 meV, respectively. From the total density of states (DOS), it is established that in all cases the GaS+ads monolayer system acquires metallic behavior. Finally, analysis of the Bader charge of the GaS+ads system just at the energetically most favorable sites shows that the Li and Na atoms transfer charge to the monolayer (cations), becoming ionized, while the Ga and S atoms transfer and gain charge from the monolayer, respectively, becoming partially ionized. This electronic behavior makes the GaS monolayer a promising material for use as an anode in batteries.

Optimizing lithium-ion diffusion in LiFePO4: the impact of Ti4+ doping on high-rate capability and electrochemical stability

Optimizing lithium-ion diffusion in LiFePO4: the impact of Ti4+ doping on high-rate capability and electrochemical stability

Prussian Blue Analogues "Dressed" in MXene Nanosheets Tightly for High Performance Lithium-Ion Batteries.

MXenes, have been considered as a new generation anode material in lithium-ion batteries for lower lithium-ion diffusion barriers and superior conductivity. Unfortunately, their structures are prone to aggregation and stacking, hindering further shuttle of lithium ions and electrons, resulting in lower discharge capacity. Therefore, the introduction of interlayer spacers for the preparation of MXene-based hybrids has attracted much attention. Introducing Prubssian blue analogues (PBAs) as a new interlayer spacer to combine with MXene nanosheets can not only preserve the high conductivity of MXene and inhibit the volume expansion and structural degradation of the PBA component, but also inherit the characteristics of large specific surface area and high porosity of PBAs. By intelligent regulating the size of MXene sheets, Co-PBA@MXene hybrids with common sandwich-like structures and superior core-shell-like structures have been successfully obtained. Furthermore, Co@M(x:y) hybrids are prepared by intelligently adjusting the shell thickness of MXene through intelligently controlling of the mass ratio between Co-PBA and MXene. Among them, the Co@M(5:2) anode exhibits an excellent capacity (603mA h g-1 at 0.2 A g-1 after 100 cycles) and superior long-term cycling stability due to the protective and conductive properties provided by the MXene shell and multi-redox pairs and rich porosity from Co-PBA core.

Cellulose-Based Materials and Their Application in Lithium-Sulfur Batteries.

Lithium-sulfur (Li-S) batteries are promising candidates for next-generation energy storage due to their high energy density, cost-effectiveness, and environmental friendliness. However, their commercialization is hindered by challenges, such as the polysulfide shuttle effect, lithium dendrite growth, and low electrical conductivity of sulfur cathodes. Cellulose, a natural, renewable, and versatile biopolymer, has emerged as a multifunctional material to address these issues. In anode protection, cellulose-based composites and coatings mitigate dendrite formation and improve lithium-ion diffusion, extending cycle life and enhancing safety. As separators, cellulose materials exhibit high ionic conductivity, thermal stability, and excellent wettability, effectively suppressing the polysulfide shuttle effect and maintaining electrolyte stability. For the cathode, cellulose-derived carbon frameworks and binders improve sulfur loading, conductivity, and active material retention, resulting in higher energy density and cycling stability. This review highlights the diverse roles of cellulose in Li-S batteries, emphasizing its potential to enable sustainable and high-performance energy storage. The integration of cellulose into Li-S systems not only enhances electrochemical performance but also aligns with the goals of green energy technologies. Further advancements in cellulose processing and functionalization could pave the way for its broader application in next-generation battery systems.

Enhanced Electrochemical Performance of Dual-Ion Batteries with T-Nb2O5/Nitrogen-Doped Three-Dimensional Porous Carbon Composites.

Niobium pentoxide (T-Nb2O5) is a promising anode material for dual-ion batteries due to its high lithium capacity and fast ion storage and release mechanism. However, T-Nb2O5 suffers from the disadvantages of poor electrical conductivity and fast cycling capacity decay. Herein, a nitrogen-doped three-dimensional porous carbon (RMF) was prepared for loading niobium pentoxide to construct a composite system with excellent electrochemical performance. The obtained T-Nb2O5/RMF composites have a well-developed pore structure and a high specific surface area of 1568.5 m2 g-1, which could effectively increase the contact area between the material and electrolyte, improving the electrode reaction and lithium-ion transfer diffusion. Nitrogen doping increased surface polarity, creating more active sites and accelerating the electrode reaction rate. The introduction of T-Nb2O5 imparted high power density and excellent cycling stability to the battery. The composites exhibited good electrochemical performance when used as dual-ion battery anode, with a stable cycle life of 207.2 mA h g-1 at 1 A g-1 current density after 650 cycles and great rate performance of 181.5 mA h g-1 at 5A g-1 was also obtained. This work provides the possibility for applying T-Nb2O5/RMF as an anode for a high-performance dual-ion battery.

Porous CuF2 derived from MOFs as cathode materials for Li-ion batteries

Copper fluoride (CuF2) has demonstrated great potential as a cathode material for LIBs owing to its high energy density. In this study, a two-step synthesis method was proposed to prepare porous CuF2 by using Cu-based metal-organic frameworks (MOFs). N2 adsorption-desorption isotherms, along with SEM and TEM analyses, proved that the intermediates CuO exerted a certain influence on the pore structure of the final CuF2 products. The porous CuF2 achieved a first discharge capacity of 554 mAh ⋅ g[Formula: see text] at 0.1C. At a high current density of 5C, it delivered a rate capacity of 413 mAh ⋅ g[Formula: see text] within 1.5–4.2 V. The results of electrochemical impedance spectroscopy show that varying degrees of porosity influence the lithium-ion diffusion coefficient, leading to differences in electrochemical performances.

Doping LiFePO4 with Al3+: Suppression of Anti-Site Defects and Implications for Battery Recycling.

In this study, a group of aluminum-doped lithium iron phosphate (LFP) with varying dopant concentrations (Li1-3x Al x FePO4/C, where x = 0.01-0.03) was synthesized via a solid-state reaction. Comprehensive analysis revealed that the aluminum dopant was uniformly distributed across the crystals of the synthesized samples. Notably, minor doping (x ≤ 0.01) helped reduce the formation of antisite defects within the LFP structure, lowering the defect content to 1.67% compared to 2.04% in undoped LFP. Further examination corroborated the presence of antisite defects and confirmed their reduced concentration in aluminum-doped LFP. Electrochemically, LAFP01 with x = 0.01 (or 1% aluminum doping) demonstrated an increased lithium-ion diffusion coefficient and superior electrochemical performance, achieving a discharge capacity of 155.6 mA h/g at a 0.1 C rate and surpassing that of undoped LFP. The performance improvement was more evident under rapid charge and discharge conditions, where LAFP01 maintained a higher specific capacity (86 mA h/g compared to 78 mA h/g for undoped LFP) at a current density of 5 C or greater. This study suggests that the reduced antisite defects with small aluminum doping could potentially contribute to the improved electrochemical characteristics of LFP cathodes, offering insights into enhancing lithium-ion battery performance and managing aluminum impurities in battery recycling processes.

Strategies for designing high-performance hard carbon anodes with enhanced lithium-ion diffusion and rate capability

The performance of the electrodes is closely related to the structure of the electrode sheet, and the construction of advanced electrodes is crucial for the lithium-ion diffusion process in high-performance lithium-ion batteries (LIBs). Hard carbon, with its irregular polycrystalline microstructure, is an ideal candidate material for the anode electrode of LIBs. However, its have some drawbacks such as low initial coulombic efficiency (ICE), low capacity and poor rate performance. In this work, two electrode casting approaches are proposed and tested in pouch cells, which are double-layer blade coated electrode and patterned coated electrode. The results show that both coating methods show a combination of high ICE and rate capability, exceeding the performance of conventional single-coated electrodes composed of the same material. The designed coating method improves the dynamics of lithium ion diffusion process in the electrode, and the magnification performance and comprehensive electrochemical performance are improved. The research has a wide application prospect and can provide design guidance for obtaining high-power batteries.

Enhanced lithium extraction from brine using surface-modified LiMn2O4 electrode with nanoparticle islands

Modification of LiMn2O4 lithium storage and diffusion using lithium storage type SnO2. Island-type modification of nanoparticles improves the electro-adsorption capacity of LMO.

2D P-doped carbon nitride as an effective artificial solid electrolyte interphase for the protection of Li anodes.

Metallic lithium plays an important role in the development of next-generation lithium metal-based batteries. However, the uncontrolled growth of lithium dendrites limits the use of lithium metal as an anode. In this context, a stable solid electrolyte interphase (SEI) is crucial for regulating dendrite formation, stability, and cyclability of lithium metal anodes. This article proposes an artificial protective layer of P-doped carbon nitride on the lithium anode surface to address these issues. A thin film of P-doped carbon nitride (CNP) was created through a simple drop-casting method using synthesized CNP powder, forming an artificial SEI on the lithium electrode. The resulting symmetric CNP-modified Li/Li cells exhibited remarkable cyclability with low overpotentials of around 40 mV over 500 cycles at a current density of 3 mA cm-2. Anode degradation and SEI composition were thoroughly studied for cycled electrodes to gain insight into the mechanisms underlying this modified surface. Furthermore, these CNP-modified anodes were successfully utilized in a Li-S coin cell battery, achieving high capacity and capacity retention at a high current density (1C). First-principles calculations indicate that P-doping in the carbon nitride structure significantly enhances the surface diffusion of lithium and promotes more homogeneous lithium plating.