Performance Lithium Research Articles

(Invited) Improving Low-Temperature Lithium-Ion Battery Performance through 3D Structure-Controlled Anodes with Optimized Charge Storage Mechanisms

The performance of lithium (Li)-ion batteries (LIBs) significantly decreases at low temperatures, primarily due to the slow diffusion of Li ions within the graphite anode. This issue often necessitates the use of complex thermal control systems to safeguard the batteries, enhancing their cost, mass, and volume, especially under extreme conditions. Here, we introduce both structure-controlled graphene and graphite composite anodes, which employ controlled charge storage mechanisms to accelerate Li-ion charge storage kinetics and maintain structural stability under low-temperature conditions. [1-3] By transitioning from layered graphite to crumpled graphene or expanded graphite (composite), we effectively utilize diffusion- and surface-controlled charge storage mechanisms. These structure-controlled anodes exhibit superior rate capability and exceptional performance at temperatures as low as -50 °C. Through comprehensive low-temperature analyses, this research provides a detailed understanding of the relationships between anode structure, charge storage mechanisms, and performance under low-temperature conditions. Our findings offer valuable insights for the development of advanced energy storage devices optimized for low-temperature operation.

Strategies for electrolyte modification of lithium-ion batteries under low-temperature environments

Because of their high energy density, high voltage platform, extended cycle life, lack of memory effect, low self-discharge rate, environmental friendliness, and quick charging, lithium-ion batteries, or LIBs, are a vital component of contemporary electronic gadgets. Temperature has a complicated and wide-ranging effect on lithium-ion batteries, though. Lithium-ion batteries will have much-reduced performance, particularly in low-temperature conditions. The total performance of batteries is significantly impacted by the quality and performance of electrolytes in China. In particular, the electrolyte’s purpose in lithium-ion batteries is primarily to convey lithium ions; the battery’s ability to function at low temperatures is greatly influenced by the electrolyte’s ion conductivity and SEI film-forming capabilities. Thus, this article begins by providing an overview of the fundamental composition and properties of lithium-ion batteries. The impact of low-temperature circumstances on lithium ion performance was then discussed. Lastly, many modification techniques were suggested from the electrolyte’s point of view to enhance lithium-ion battery performance in low-temperature settings.

Preparation and lithium-storage performance of (Ti1−x,Vx)3C2 MXene solid solutions

Two-dimensional Ti3C2 MXene shows excellent lithium-storage performance as an anode of lithium-ion batteries. The replacement of Ti with V can enhance the lithium-storage performance, but decrease the stability of Ti3C2 MXene. To understand the impact of V replacement, in this study, a series of (Ti1−x,Vx)3C2 (x = 0, 0.1, 0.2…0.6) MXene solid solutions were prepared. The stability and lithium storage performance of the MXene solutions were investigated. The precursors to make (Ti1−x,Vx)3C2 MXene were MAX phase solid solutions of (Ti1−x,Vx)3AlC2, which were made from TiH2, V, Al and C powders at 1400 °C for 2 h under Ar atmosphere. Because of the replacement of > 60 at% Ti by V destroys the stability of the (Ti1−x,Vx)3AlC2, the MAX solid solutions with x ≤ 0.6 were synthesized in this study. (Ti1−x,Vx)3C2 MXene was made from the corresponding MAX phases by the etching in mixed solutions of NaF + HCl. (Ti1−x,Vx)3C2 MXene (x = 0–0.4) were synthesized at 60 °C for 2 days, and the MXene (x = 0.5–0.6) were synthesized at 70 °C for 6 days. All (Ti1−x,Vx)3C2 solid solutions had better electrochemical performance than pure Ti3C2 MXene. Especially, (Ti0.7,V0.3)3C2 exhibited the best performance. The capacity of (Ti0.7,V0.3)3C2 was 183.5 mAh/g after 100 cycles at a current density of 500 mA/g, which was ∼4.3 times of the capacity of the pure Ti3C2 (42.2 mAh/g at 500 mA/g). This is the first report to clarify the effect of V replacement on the stability and lithium performance on (Ti1−x,Vx)3C2 MXene solid solution. This work is critical for the synthesis of novel MXenes and MAX phases. It provides a way to make a MXene that is very close to V3C2 MXene, which is theoretically predicted but cannot be made. This work is vital for the enhancement of MXenes’ electrochemical performance.

Loadings of Functionalized Multiwalled Carbon Nanotubes for Enhancing Sulfurized Polyacrylonitrile Performance in Lithium–Sulfur Batteries

Loadings of Functionalized Multiwalled Carbon Nanotubes for Enhancing Sulfurized Polyacrylonitrile Performance in Lithium–Sulfur Batteries

Paradigm metallothermic-sulfidation-carbonization constructing ZIFs-derived TMSs@Graphene/CNx heterostructures for high-capacity and long-life energy storage

Enhancing electrochemical activity and structural stability of transition metal sulfides (TMSs) are critical for improving the capacity output and retention of TMSs-based batteries. Here, we report a new paradigmatic approach for fabricating TMSs/C composites, adopting a metallothermic-sulfidation-carbonization strategy (2TM + CS2 = 2TMS + C) based on zeolitic imidazolate frameworks (ZIFs) to synchronously construct a compact TMSs@Graphene/CNx triple heterostructure. The obtained structure features crystalline TMSs nanoparticles wrapped by few-layer graphene and totally embedded within porous carbonized polyhedral frameworks. All three nanocomponents of TMSs@Graphene/CNx are connected via chemical bonding of S−C and TM−C, forming a chemical cross-linked nanostructure. Such structure design bears intrinsic advantages in improving the volumetric-efficiency for accommodating TMSs and electrical properties, enabling promising electrochemical performance in lithium- and sodium-ion storage. As a representative, the ZnS@Graphene/CNx electrode exhibits a high capacity of 891.5 mAh g−1 and an excellent retention of 80 % after 1000 cycles in lithium-ion batteries. More notably, this general metallothermic-sulfidation-carbonization mechanism can be applicable to all ZIFs, defining a new ZIFs-derived TMSs/C heterostructures.

Facile synthesis of elemental sulfur-mediated fluorine-containing covalent triazine frameworks and their performance in lithium–sulfur batteries

The structure diagram of SFN-CTFs and the cycle diagram of SFN-CTF(1 : 2)-1 are presented.

High-rate performance and suppressed voltage decay of Li and Mn-rich oxide cathode materials upon substitution of Mn with Co for Li-ion batteries

In the current study, we found that the substitution of Mn in Li and Mn-rich oxides with Co results in the improved electrochemical performance in Li-ion batteries. The Co-containing Li and Mn-rich oxide, Li 1.2 Ni 0.2 Mn 0.48 Co 0.12 O 2 exhibit a specific capacity of about 205 mAh g -1 at C/5 rate with 83% capacity retention after 140 cycles along with a higher rate capability and also maintained a higher average discharge voltage upon cycling than that of Li 1.2 Ni 0.2 Mn 0.6 O 2 . • Influence of Co on the performance of Li and Mn-rich oxides has been tested. • Li 1.2 Ni 0.20 Mn 0.48 Co 0.12 O 2 exhibits a high specific capacity of 224 mAh g -1. • Interestingly, Li 1.2 Ni 0.2 Mn 0.48 Co 0.12 O 2 exhibits a specific capacity of 113 mAh g -1 at 4C rate, which is higher than Li 1.2 Ni 0.2 Mn 0.6 O 2 (70 mAh g -1 ) • EIS study indicates the low charge transfer resistance at high voltages for Li 1.2 Ni 0.2 Mn 0.48 Co 0.12 O 2. Layered Lithium and Mn-rich oxides, xLi 2 MnO 3 ·(1–x) LiMO 2 (M=Ni, Mn, Co) such as Li 1.2 Ni 0.2 Mn 0.6 O 2 (without Co) and Li 1.2 Ni 0.13 Mn 0.54 Co 0.13 O 2 (upon substitution of both Mn and Ni with Co) are reported with high specific capacity. However, there is no report yet on the performance of Lithium and Mn-rich oxides when only Mn in these oxide cathodes is partially substituted with Co. In the current study, Lithium and Mn-rich cathodes such as Li 1.2 Ni 0.2 Mn 0.6 O 2 (LNMO) and Li 1.2 Ni 0.20 Mn 0.48 Co 0.12 O 2 (LNMCO) are synthesized by a sol-gel method followed by sintering at 900 o C for 12 h and their electrochemical performance has been evaluated at C/10 rate for 2 cycles (2.0 - 4.7 V) followed by 2.0-4.6 V at C/5 rate for 140 cycles. LNMO and LNMCO exhibit initial discharge capacities of around 210 and 224 mAh g -1 , respectively at the C/10 rate, with capacities retentions of 80.9 and 82.4 % after 140 cycles upon cycling at the C/5 rate. However, with an increase in the rate, Li 1.2 Ni 0.2 Mn 0.6 O 2 has a specific capacity around 70 mAh g -1 at 4C current rate, whereas Li 1.2 Ni 0.20 Mn 0.48 Co 0.12 O 2 exhibits 113mAh g -1 at the same current rate. This result clearly demonstrates that Li 1.2 Ni 0.20 Mn 0.48 Co 0.12 O 2 has a better rate capability than Li 1.2 Ni 0.2 Mn 0.6 O 2 material. During cycling, an excessive average discharge voltage is also maintained for Li 1.2 Ni 0.20 Mn 0.48 Co 0.12 O 2 .

N/O dual-doped hierarchical porous carbon boosting cathode performance of lithium—sulfur batteries

A combination of NaOH activation and continuous pyrolysis of biomass is used to prepare N and O dual-doped hierarchical porous carbon as the carrier of Li—S batteries from egg, yolk and albumen respectively. Among the three sources, the biomass porous carbon derived from albumen has the most abundant hierarchical pore morphology. Its specific surface area, average pore diameter, and sulfur loading are 693.0 m2 · g−1, 3.1 nm and 62.0 wt.%, respectively. The albumen-derived porous carbon/sulfur (AC/S) electrode exhibits excellent reversibility and electrochemical performance (1115 mAh · g−1 at 0.05 C) due to the synergistic effect of hierarchical pore structure and element doping. The rate capacity of AC/S is 15% and 25% higher than that of egg-derived porous carbon/sulfur (EC/S) and yolk-derived carbon/sulfur (YC/S) at 2 C. And the capacity retention rate of AC/S after 50 cycles is 77%, which is 15% and 11% higher than those of EC/S and YC/S, respectively.

Phosphorus doping of 3D structural MoS2 to promote catalytic activity for lithium-sulfur batteries

To address the issues of “shuttle effect” of soluble polysulfides and sluggish redox kinetics in the cathodes of lithium-sulfur batteries, the acceleration of the polysulfides conversion via electrocatalysis is a promising solution. As a common electrocatalyst, the catalytic ability of two dimensional (2D) MoS2 is considerably diminished due to agglomeration of nanosheets and insufficient active sites. In this work, a phosphorus-doped three dimensional (3D) network of MoS2-based interlayer sandwiched between the S cathode and the separator is developed. The 3D network could prevent 2D nanosheets from stacking and provide fast diffusion channels for Li ions transfer. Phosphorus doped MoS2 forms stronger Mo-S and Li-P bonds to anchor polysulfides and to promote cleavage of S-S or Li-S bonds of lithium polysulfides to accelerate the polysulfides conversion. As a result, the cell exhibits a high specific capacity of 884.4 mAh g−1 after 100 cycles at 0.1C even under the high sulfur loading condition (3.7 mg cm−2). This work may encourage more efforts on heteroatom doping in electrocatalyst to realize a high performance in lithium–sulfur batteries.

Facile Synthesis of Carbon Nanospheres with High Capability to Inhale Selenium Powder for Electrochemical Energy Storage.

Carbon–selenium composite positive electrode (CSs@Se) is engineered in this project using a melt diffusion approach with glucose as a precursor, and it demonstrates good electrochemical performance for lithium–selenium batteries. X-ray diffraction (XRD) and scanning electron microscopy (SEM) with EDS analysis are used to characterize the newly designed CSs@Se electrode. To complete the evaluation, electrochemical characterization such as charge–discharge (rate performance and cycle stability), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS) tests are done. The findings show that selenium particles are distributed uniformly in mono-sized carbon spheres with enormous surface areas. Furthermore, the charge–discharge test demonstrates that the CSs@Se cathode has a rate performance of 104 mA h g−1 even at current density of 2500 mA g−1 and can sustain stable cycling for 70 cycles with a specific capacity of 270 mA h g−1 at current density of 25 mA g−1. The homogeneous diffusion of selenium particles in the produced spheres is credited with an improved electrochemical performance.

Influence of lithium and silicon coatings on tungsten erosion in arc plasma

• Arc erosion of W substrate can be effectively mitigated by Li and Si coatings. • Selective formation of spots on coatings is responsible for erosion mitigation. • Vapor shielding of Li coating provides effective mitigation of tungsten erosion. Arc spots formed on a plasma-facing component (PFC) have a stunning resemblance with the arc spots formed on a cathode of a vacuum arc. Hence, in this paper, a laboratory-scale vacuum arc process is used to get a better understanding of the arc erosion process of the tungsten (W) material. The performance of lithium (Li) and silicon (Si) coatings in erosion mitigation of W material is analyzed. The virgin W substrate was eroded significantly by arc spots and numerous W droplets were ejected into the interelectrode plasma from cathode with velocity of tens m/s. However, the W substrates can be effectively protected by Li and Si coatings from arc erosion. Preferential formation of arc spots on the coatings is responsible for the arc erosion mitigation. Compared with the virgin W substrate, no ejection of W droplets from the cathode was observed in the cases of coatings. Li and Si droplets were accidently ejected from the cathode and the ejected droplets were rapidly ablated in the arc plasma. For the case of Si coating, the W substrate was slightly melted and eroded due to the arc spots formed on the coating. By contrast, no obvious melting and erosion were observed on the W substrate for the case of Li coating, which is possibly due to the vapor shielding effect of Li between the W substrate and arc spots. These results confirm coatings served as a sacrificial protective layer and can reduce tungsten surface erosion caused by arcs, which provides a new reference for protecting first wall materials in future fusion devices.

Recent progress in the function of redox mediators on the electrode/electrolyte interfaces of lithium–oxygen batteries

The nonaqueous lithium–oxygen batteries have attracted considerable interest because of the ultrahigh theoretical capacity. However, the overpotential and cyclability issue of lithium–oxygen battery caused by interfacial issue limits its commercialization. To overcome these challenges, redox mediators, which are capable of charge transport on the electrode/electrolyte interfaces, are introduced to lithium–oxygen batteries to reduce overpotential. This review provides a detailed summary of the interfacial reaction mechanism and the influence of redox mediators on the electrode/electrolyte interfaces. Researches on suppressing redox mediators’ shuttle effect are also beneficial to enhance the electrochemical performance of lithium–oxygen batteries.

Freestanding interlayers for Li–S batteries: design and synthesis of hierarchically porous N-doped C nanofibers comprising vanadium nitride quantum dots and MOF-derived hollow N-doped C nanocages

Herein, a hierarchically developed multifunctional, porous, and freestanding interlayer is utilized for efficient polysulfide absorption and superior electrochemical performance in lithium–sulfur cells with sulfur cathode and low electrolyte volume.

Optimisation of Direct Battery Thermal Management for EVs Operating in Low-Temperature Climates

Electric vehicles (EVs) experience a range reduction at low temperatures caused by the impact of cabin heating and a reduction in lithium ion performance. Heat pump equipped vehicles have been shown to reduce heating ventilation and air conditioning (HVAC) consumption and improve low ambient temperature range. Heating the electric battery, to improve its low temperature performance, leads to a reduction in heat availability for the cabin. In this paper, dynamic programming is used to find the optimal battery heating trajectory which can optimise the vehicle’s control for either cabin comfort or battery performance and, therefore, range. Using the strategy proposed in this research, a 6.2% increase in range compared to no battery heating and 5.5% increase in thermal comfort compared to full battery heating was achieved at an ambient temperature at −7 °C.

Metal-Organic Framework-Derived Co3 V2 O8 @CuV2 O6 Hybrid Architecture as a Multifunctional Binder-Free Electrode for Li-Ion Batteries and Hybrid Supercapacitors.

Metal-organic frameworks (MOFs) are promising materials in diverse fields because of their constructive traits of varied structural topologies, high porosity, and high surface area. MOFs are also an ideal precursor/template to derive porous and functional morphologies. Herein, Co3 V2 O8 nanohexagonal prisms are grafted on CuV2 O6 nanorod arrays (CuV-CoV)-grown copper foam (CF) using solution-processing methods, followed by thermal treatment. Direct preparation of active material on CF can potentially eliminate electrochemically inactive and non-conductive binders, leading to improved charge-transfer rate. Furthermore, solution-processing methods are simple and cost-effective. Owing to versatile valence states and good redox activity, the vanadium-incorporated mixed metal oxides (CuV-CoV) exhibited superior electrochemical performance in lithium (Li)-ion battery and supercapacitor (SC) studies. Furthermore, hollow carbon particles (HCPs) derived from MOF particles (MOF-HCPs) are used as the anode material in SCs. A hybrid SC (HSC) fabricated with CuV-CoV and MOF-HCP materials exhibited noteworthy electrochemical properties. Moreover, a solid-state HSC (SSHSC) is constructed and its real-time feasibility is investigated by harvesting the dynamic energy of a bicycle with the help of a direct current generator. The charged SSHSCs potentially powered various electronic components.

Parametric and Performance Investigations on Novel Multipurpose Liquid Desiccant Drying/Desalination System

In humid climates, due to high relative humidity present in the ambient air, traditional air drying system is becoming inefficient for drying the agricultural/food products. On the other hand, there is a scarcity of useful drinking water in many parts of the world. In order to meet the aforementioned requirements, a novel multipurpose liquid desiccant drying/desalination system has been proposed in the present study by replacing water as a working fluid instead of air in the liquid desiccant regenerator and by adding an energy efficient heat exchanger to the conventional liquid desiccant air conditioning system. A thermal model has been developed for assessing the performance of the novel system and for comparing the performance of the novel system with conventional system. Using the developed model, parametric studies on novel and conventional systems are carried out by choosing the system efficiency as a performance criterion and Lithium chloride as a liquid desiccant. From the parametric studies and performance comparison analysis, it is observed that novel system efficiency is 20.8% higher than the conventional system and the amount of pure water extracted from the novel system is observed to be 4.3 l/min as a byproduct.

Improving Rechargeable Battery Dynamics

A series of experiments was undertaken to study the effects of additive changes on the plating of zinc metal from zinc chloride solutions. From these simple examples it was hoped to offer explanations for several different effects seen in battery performance.The avenue chosen was to observe the effect of adding a leveling agent and then a pH adjustment with a particular chemical based on previous experience to see if an outstanding result would be observed. Accidentally it was more important to find that the specific characteristics of the current supply were more important than the additives. Nonetheless the best result was achieved with a combination of these factors.It was hoped at the same time to better understand the effects of diffusion on the chemical process and its response to changes in the diffusion, especially locally. It is necessary to recognize that knowing the chemical reactions on paper does not accurately predict what happens in an active rechargeable cell. The effects of diffusion limit the concentration of chemicals and often the actual reactions in both the separator structure and in the electrolyte and in the surface regions contacted by the electrolyte. This is true for both the discharging and charging cell environment. Photos and current analysis will be shown.From these or similar experiments it may be possible to predict the parallel performance in lithium or lithium ion cells and how to extend cycle life. Discussion will be invited.

Pt Nanoparticles-Macroporous Carbon Nanofiber Free-Standing Cathode for High-Performance Li-O2 Batteries

Controlling the pore structure of cathodes has a decisive effect on the performance of lithium (Li)-O2 batteries. In this work, macroporous carbon nanofiber (MCNF) decorated with Pt nanoparticles (PtNPs) (PtNP-MCNF) are successfully fabricated. Their electrochemical performance as cathodes for a Li-O2 battery is evaluated. The MCNF mats are fabricated through an electrospinning and templating method using cross-linked polystyrene particles. PtNPs are grown on the surface of the MCNF through a solvothermal reaction. As-prepared PtNP-MCNF has interconnected macropores along the MCNF interior and abundant surface openings. These macropores are also connected to larger pores between individual MCNFs through the orifices on the MCNF surface, rendering a hierarchical porous structure. Owing to the highly porous structure and catalytic activity of PtNPs, Li-O2 cells using PtNP-MCNF cathodes exhibit considerably improved performance. In particular, with regard to cycle stability, the Li-O2 cell using PtNP-MCNF attains over 470 cycles in total while discharging at a capacity of 1000 mAh gc−1 with a current density of 500 mA gc−1. Such a high performance of the Li-O2 cell can be attributed to a facilitated Li+ and O2 transportation through the highly porous structure, and highly reversible Li-O2 operation over its life-cycle by means of catalytic activity of PtNPs.

Nitrogen-doped carbon nanotubes intertwined with porous carbon with enhanced cathode performance in lithium–sulfur batteries

A nitrogen-doped CNT threaded polyaniline hydrogel-derived porous carbon structure greatly improves the energy storage performance when integrated into a Li–S battery cathode.

Shuttle confinement of lithium polysulfides in borocarbonitride nanotubes with enhanced performance for lithium–sulfur batteries

Borocarbonitride nanotubes show efficient physical and chemical anchoring and conversion of lithium polysulfides, ensuring the enhanced electrochemical performance in lithium–sulfur batteries.