Current Lithium-ion Batteries Research Articles

Stochastic Expansion Planning of Various Energy Storage Technologies in Active Power Distribution Networks

This work aims to minimize the cost of installing renewable energy resources (photovoltaic systems) as well as energy storage systems (batteries), in addition to the cost of operation over a period of 20 years, which will include the cost of operating the power grid and the charging and discharging of the batteries. To this end, we propose a long-term planning optimization and expansion framework for a smart distribution network. A second order cone programming (SOCP) algorithm is utilized in this work to model the power flow equations. The minimization is computed in accordance to the years (y), seasons (s), days of the week (d), time of the day (t), and different scenarios based on the usage of energy and its production (c). An IEEE 33-bus balanced distribution test bench is utilized to evaluate the performance, effectiveness, and reliability of the proposed optimization and forecasting model. The numerical studies are conducted on two of the highest performing batteries in the current market, i.e., Lithium-ion (Li-ion) and redox flow batteries (RFBs). In addition, the pros and cons of distributed Li-ion batteries are compared with centralized RFBs. The results are presented to showcase the economic profits of utilizing these battery technologies.

Enhanced Cycling and Rate Capability by Epitaxially Matched Conductive Cubic TiO Coating on LiCoO2 Cathode Films.

Layered lithium transition-metal oxides, such as LiCoO2 and its doped and lithium-rich analogues, have become the most attractive cathode material for current lithium-ion batteries due to their excellent power and energy densities. However, parasitic reactions at the cathode–electrolyte interface, such as metal-ion dissolution and electrolyte degradation, instigate major safety and performance issues. Although metal oxide coatings can enhance the chemical and structural stability, their insulating nature and lattice mismatch with the adjacent cathode material can act as a physical barrier for ion transport, which increases the charge-transfer resistance across the interface and impedes cell performance at high rates. Here, epitaxial engineering is applied to stabilize a cubic (100)-oriented TiO layer on top of single (104)-oriented LiCoO2 thin films to study the effect of a conductive coating on the electrochemical performance. Lattice matching between the (104) LiCoO2 surface facets and the (100) TiO plane enables the formation of the titanium mono-oxide phase, which dramatically enhances the cycling stability as well as the rate capability of LiCoO2. This cubic TiO coating enhances the preservation of the phase and structural stability across the (104) LiCoO2 surface. The results suggest a more stable Co3+ oxidation state, which not only limits the cobalt-ion dissolution into the electrolyte but also suppresses the catalytic degradation of the liquid electrolyte. Furthermore, the high c-rate performance combined with high Columbic efficiency indicates that interstitial sites in the cubic TiO lattice offer facile pathways for fast lithium-ion transport.

Comparison of Ionic Transport Properties of Non-Aqueous Lithium and Sodium Hexafluorophosphate Electrolytes

To bridge the gap between current lithium-ion battery technology and alternative cell chemistries such as, e.g., sodium-ion batteries, the majority of the research in this field focuses on the improvement of the cell’s energy density by the development of new active materials for reversible storage of sodium ions. On the other hand, the power density, which is determined by the ionic transport and thermodynamic parameters in the electrolyte, namely the conductivity, the thermodynamic factor, the transference number, and the diffusion coefficient, is attracting little attention. In this contribution, we determine these electrolyte properties for 0.1 M to 2 M LiPF6 and NaPF6 in a mixture of ethylene carbonate and diethyl carbonate (EC:DEC (1:1 v:v)) and use them in 1D simulations to show their impact on the theoretical discharge rate performance of the lithium and sodium cell chemistry. We show that the increased cation size of sodium and its corresponding weaker solvent interactions are beneficial for high power applications and that the improved ionic transport properties would allow for a substantial increase of either the (dis)charge currents or the electrode areal loading, compared to the well-established lithium system.

Experimental determination of Li diffusivity in LLZO using isotopic exchange and FIB-SIMS

Current lithium ion battery technology makes use of flammable liquid electrolytes and so the development of solid ceramic electrolytes for the next generation of all-solid-state batteries can offer a safer alternative. However, the lithium diffusion behaviour in these solid electrolytes is not yet well characterised, despite the importance of this information for optimising cell performance. Similarly, the transport properties at the metal anode interface are critically important, but not well understood. We propose a methodology for obtaining lithium diffusion coefficients of bulk solid ceramic garnet-type Li7La3Zr2O12 (LLZO) electrolytes by coupling dense pellets with isotopically labelled lithium metal, followed by analysis with focused-ion-beam secondary ion mass spectrometry. We report room temperature lithium diffusivities of 2–8 × 10−13 m2 s−1 for doped LLZO using an estimate of the lithium diffusion length in good agreement with electrochemical impedance spectroscopy. Simultaneous detection of positive and negative secondary ion species by SIMS enables correlation of layered interfaces consisting of metallic lithium, corrosion/surface degradation products and bulk LLZO during depth profiling. Charging of the ceramic during ion sputtering is investigated and shown to have a minimal effect on the obtained lithium isotopic fractions in the current setup. Additionally, the effect of the presence of corrosion products at the surface of garnets as a result of air-exposure is investigated. This method could be extended to any Li-metal stable solid electrolyte, or with a reactive solid electrolyte coupled with a stable interlayer. As such, this work sets the basis of a methodology for further quantitative diffusion analyses for Li-conducting solid ceramic electrolytes and their interfaces with electrodes, as used in both solid-state lithium batteries and hybrid systems coupling solid and liquid electrolytes.

Guest-species-incorporation in manganese/vanadium-based oxides: Towards high performance aqueous zinc-ion batteries

Aqueous zinc-ion batteries (AZIBs) are considered as a promising alternative to the current lithium-ion battery system due to their environmental benignity, high safety, and cost-effectiveness. Recently, significant research progress has been achieved in the development of manganese/vanadium oxides for AZIBs via guest species incorporation, whereby the intrinsic capacity and cycling stability have been enhanced through improving the structural stability and accelerating the Zn 2+ /e - transportation. In this review, we present an overview of the recent advances in the guest species incorporation of manganese/vanadium oxides for AZIBs. The crystal structures and zinc storage mechanisms have been analyzed with considerations of effects of the various types of guest species incorporated into manganese/vanadium oxides. We also summarized the design strategies, structural advantages and future perspectives of the guest species incorporation for the well-established research in AZIBs. Significant research progress has been achieved in the development of manganese/vanadium oxides for AZIBs via guest species incorporation. In this review, we present an overview of the recent advances in the guest species incorporation of manganese/vanadium oxides for AZIBs, including zinc storage mechanisms and effects of the various types of guest species incorporation. We also summarized the design strategies, structural advantages and future perspectives of the guest species incorporation for AZIBs. • A detailed summary of Zinc storage mechanism and existing issues of manganese/vanadium oxides. • An overview of preparation strategies and effects of guest species in manganese/vanadium oxides. • Provided important highlights of recent advances of guest species incorporation in manganese/vanadium oxides. • Inspiration and future perspectives.

What Can be Expected from “Anode‐Free” Lithium Metal Batteries?

“Anode‐free” lithium metal batteries are cells that have no excess lithium metal. They have become a topic of tremendous attention, mostly driven by recent progress and interest in practical batteries with Li metal anodes. These cells are expected to provide improved performance. However, a deeper analysis on the potential manufacturing costs have not been weighed against the cell attributes. Specifically, the increased energy density and gravimetric energy density of anode‐free cells versus their reduced cycle life when compared with standard lithium‐ion batteries (LIB). In this perspective, a multifaceted comparison between anode‐free batteries with current LIB and future Li metal‐based batteries is shown. Furthermore, not only an overview of the research strategies on the anode‐free design is provided but also attempted to estimate the potential advantages weighed in different scenarios considering cost, performance, processing, and technology maturity.

Low-Concentrated Lithium Hexafluorophosphate Ternary-based Electrolyte for a Reliable and Safe NMC/Graphite Lithium-Ion Battery.

Current commercial lithium-ion battery (LIB) electrolytes are heavily influenced by the cost, chemical instability, and thermal decomposition of the lithium hexafluorophosphate salt (LiPF6). This work studies the use of an unprecedently low Li salt concentration in a novel electrolyte, which shows equivalent capabilities to their commercial counterparts. Herein, the use of 0.1 M LiPF6 in a ternary solvent mixture of ethylene carbonate (EC), ethyl methyl carbonate (EMC), and 1,1,2,2-tetrafluoroethyl 2,2,2-trifluoroethyl ether (TFE) (3EC/7EMC/20TFE, by weight) is investigated for the first time in LiNi1/3Mn1/3Co1/3O2 (NMC111)/graphite pouch cells. In solution, the Li+ transport number and diffusion are governed by the Grotthuss mechanism, with transport properties being independent of salt concentration. The proposed electrolyte operates in a wide temperature window (0-40 °C), is nonflammable (self-extinguishing under 2 s), and shows adequately fast wetting (4 s). When incorporated into the NMC/graphite pouch cell, it initially forms a solid electrolyte interphase (SEI) with minimal gas formation followed by a comparable battery performance to standard LiPF6 electrolytes, validated by a high specific capacity of 165 mAh g-1, Coulombic efficiencies of 99.3%, and capacity retention of 85% over 700 cycles.

Transport of Sodium Ions in Solids: Progress in First‐Principle Theoretical Formulation of Potential Solid Sodium‐Ion Electrolytes

AbstractAll‐solid‐state sodium ion batteries (ASSIBs) have attracted great attention due to ever‐increasing safety concern about current lithium ion batteries and the limited natural reserves of lithium. A major materials basis to enable high‐performance ASSIBs lies in delivering ultra‐fast Na+ conductors, which is yet even more challenging than developing solid electrolytes for the lithium‐ion batteries. This is largely attributed to limited fundamental understanding of the transportation characteristics of sodium ions, which is rather different from the smaller alkali lithium ions. Here, we have carried out a perspective review of recent advances in theoretical formulation of novel solid electrolytes, focusing on methods, achievements, and the potential and shortcomings of identified materials systems. Efforts are made in offering a dependable framework to formulate fundamentally competitive materials to support developing “better” solid sodium‐ion batteries.

Environmental assessment of a new generation battery: The magnesium-sulfur system

As environmental concerns mostly drive the electrification of our economy and the corresponding increase in demand for battery storage systems, information about the potential environmental impacts of the different battery systems is required. However, this kind of information is scarce for emerging post-lithium systems such as the magnesium-sulfur (MgS) battery. Therefore, we use life cycle assessment following a cradle-to-gate perspective to quantify the cumulative energy demand and potential environmental impacts per Wh of the storage capacity of a hypothetical MgS battery (46 Wh/kg). Furthermore, we also estimate global warming potential (0.33 kg CO2 eq/Wh) , fossil depletion potential (0.09 kg oil eq / Wh), ozone depletion potential (2.5E-08 kg CFC-11/Wh) and metal depletion potential (0.044 kg Fe eq/Wh), associated with the MgS battery production. The battery is modelled based on an existing prototype MgS pouch cell and hypothetically optimised according to the current state of the art in lithium-ion batteries (LIB), exploring future improvement potentials. It turns out that the initial (non-optimised) prototype cell cannot compete with current LIB in terms of energy density or environmental performance, mainly due to the high share of non-active components, decreasing its performance substantially. Therefore, if the assumed evolutions of the MgS cell composition are achieved to overcome current design hurdles and reach a comparable lifespan, efficiency, cost and safety levels to that of existing LIB; then the MgS battery has significant potential to outperform both existing LIB, and lithium-sulfur batteries.

Safe and efficient phosphonium ionic liquid based electrolyte for high-potential LiMn2O4 and LiNi0.8Co0.15Al0.05O2 cathodes for Li-ion batteries

Electrolytes are essential constituents for safe and reliable battery performance. Current lithium-ion battery (LIB) systems present an inherent safety problem stemming from the use of metal oxide cathodes, which are oxygen sources, and flammable electrolytes based primarily on organic carbonates. Herein we report a novel non-flammable electrolyte formulated by the addition of 30% wt. of methyltributhylphosphonium Bis(trifluoromethanesulfonyl) imide [Bu3MeP][TFSI] ionic liquid (IL) to a standard electrolyte (SE, ethylene carbonate (EC): ethyl methyl carbonate (EMC) 1:1 wt/wt) + 1M LiPF6). The good physicochemical properties of the IL, (i) mitigate the ignition delay and flammability of the proposed electrolyte and (ii) markedly improve the interfacial resistance of the LiMn2O4//Li and LiNi0.8Co0.15Al0.05O2//Li half-cells. The half-cells' performance indicates that the conveyed hybrid electrolyte (HE) retains a higher portion of its energy density (629 vs. 446 Wh.kg−1 for HE and SE in an NCA//Li half-cell, accordingly). At 60°C, [Bu3MeP] [TFSI] considerably improved the cathode performance in terms of capacity (up to 230 mAh.g−1 for NCA) and coulombic efficiency (>99%).

Lactone-Based Liquid Electrolytes for Fluoride Shuttle Batteries

Rechargeable secondary batteries operating through fluoride-ion shuttling between the positive and negative electrodes, referred to as fluoride shuttle batteries (FSBs), offer a potentially promising solution to overcoming the energy-density limitations of current lithium-ion battery systems. However, there are many technical issues that need to be resolved to achieve high-quality fluoride-carrying electrolytes and ensure reversible transformations between a metal and its fluoride counterpart at both electrodes. Here, we introduce novel lactone-based liquid electrolytes consisting either of CsF or KF, which are prepared by a solvent substitution method. Although the maximum fluoride-ion concentration achieved by the method is approximately 0.05 M, these systems behave as strong electrolytes where CsF(KF) is almost fully dissociated into Cs+(K+) and F− ions to give a maximum ionic conductivity of 0.8 mS.cm−1. Hence, the solvent supports electrochemically active fluoride ions that can drive reversible metal/metal-fluoride transformations at room temperature for a wide range of metal electrodes. However, irreversible reductive reactions of the solvent, also promoted by the fluoride ions, limit currently the negative potential window to approximately −1.5 V vs the standard hydrogen electrode.

Economic Feasibility of Micro-Grid Energy Storage and the Impact of Emerging Technologies on Its Viability

Currently, energy storage devices show great promise when used in micro-grid applications, and further advancements in this technology will lead to economically-viable and environmentally-friendly solutions in regards to residential energy consumption. Creating a 21st-century energy infrastructure will be fundamental to society in the coming decades and ensuring cost-effective means of doing so will lessen the burden on the average consumer. While current research has focused primarily on fundamental battery research, the economic viability for the average American consumer has been neglected in many cases. In this work, current and future methods of home energy storage are analyzed via a thorough literature review and the most promising current and near-future methods are explored. These methods include current Lithium-Ion Battery (LIB) technology, reused LIB from Electric Vehicles (EVs), Lithium Nickel manganese cobalt oxides (NMC) cathode composition and the utilization of silicon as an anode material. After the potential of these technologies is explored, an analysis of their economic viability for the average consumer is presented. The literature review demonstrates that the current state of LIB is very close to economically feasible; reused LIBs are less viable than new LIBs, and future LIB compositions show great promise in viability. This shows that within the next decade, micro-grids will be a reasonable alternative to utility energy harnessing techniques, and a major step towards green energy consumption will be realized. Hybrid energy storage systems, on the other hand, are shown to be economically infeasible, in the near future, due to their high cost per kWh. However, when analyzing the energy storage capabilities of these systems, it is shown that they may be vital in updated energy infrastructure and provide a cost saving.

On the environmental competitiveness of sodium-ion batteries under a full life cycle perspective – a cell-chemistry specific modelling approach

Assessing different sodium-ion against current lithium-ion battery cells shows large difference between cell chemistries and a good environmental performance for manganese and Prussian blue-based cathodes under a full life cycle perspective.

Enhanced Electrochemical Stability of Sulfide‐Based LiNi0.8Mn0.1Co0.1O2 All‐Solid‐State Batteries by Ti Surface Doping

AbstractAll‐solid‐state batteries (ASSBs) using inorganic superionic conductors are considered a safer alternative to the current lithium ion battery technology. And tackling the issue of interfacial stability between the solid‐state electrolyte and electrode active material is a critical step to achieving sustainable ASSBs. In this work, we applied a TiO2 surface coating on LiNi0.8Mn0.1Co0.1O2 (NMC811) particles through a dry‐coating process, and subsequently heat‐treated the TiO2‐coated materials. We systematically characterized the changes to the material after the coating and heating processes, and we explored the role of TiO2 coating and heat‐treatment on the electrochemical cycling of NMC811 in a sulfide‐based ASSB. The coating and heat treatment resulted in Ti doped into the NMC811 surface, which reduced undesired side reactions and improved cycling stability. Capacity retention of the doped material was 55 % at 50 cycles, versus 11 % in the un‐doped material. The observations in this study provide an alternative approach toward enhancing the interfacial stabilities between high‐energy NMC materials and sulfide‐based solid‐state electrolyte.

The Current Process for the Recycling of Spent Lithium Ion Batteries

With the development of electric vehicles involving lithium ion batteries as energy storage devices, the demand for lithium ion batteries in the whole industry is increasing, which is bound to lead to a large number of lithium ion batteries in the problem of waste, recycling and reuse. If not handled properly, it will certainly have a negative impact on the environment and resources. Current commercial lithium ion batteries mainly contain transition metal oxides or phosphates, aluminum, copper, graphite, organic electrolytes containing harmful lithium salts, and other chemicals. Therefore, the recycling and reuse of spent lithium ion batteries has been paid more and more attention by many researchers. However, due to the high energy density, high safety and low price of lithium ion batteries have great differences and diversity, the recycling of waste lithium ion batteries has great difficulties. This paper reviews the latest development of the recovery technology of waste lithium ion batteries, including the development of recovery process and products. In addition, the challenges and future economic and application prospects are described.

Stabilized 3-D Foam for Ultra-Stable and Fast-Charging Lithium Metal Anode

Current lithium ion batteries almost reached the practical energy density and needs further innovation at materials chemistry and design. Lithium metal holds the highest specific capacity among the possible anode materials for Li-ion batteries. However, the complex and parasitic interfacial reaction between lithium metal and electrolyte hinders the practical application of lithium metal as anode in secondary batteries. Therefore, stabilizing the interface of lithium metal is crucial for their application in automotive batteries and grid-scale energy storage devices. In this study, the interface of the lithium metal anode was tailored using a simple and strategical approach by a) regulating uniform deposition and stripping of lithium ions on to the 3-D structured foam and b) stabilizing the cycle life of the anode. A facile and cost effective method was adopted to uniformly deposit the carbon material on to the 3-D scaffold. The performance was analyzed using various structural and electrochemical performance studies. As a result of this study, the Li-ion cell delivered a stable cycling performance of over 400 cycles with 98.5% Coulombic efficiency. Also, post-mortem analysis of the lithium metal anode was performed to establish fundamental understanding on the interfacial protection mechanism. These results provide valuable insights for advanced design of lithium metal anode with uniform protective coating.

Sheet Type All-Solid-State Batteries with Sulfide Electrolyte

Lithium ion batteries have received great attention due to emerging electric vehicle market to suppress global climate change issues. Batteries with higher energy density is required to improve driving distance of electric vehicle. As energy density increase, safety become more important point to prevent unexpected accident. Safety issues of current lithium ion battery system mainly comes from the oxide cathode and flammable organic electrolyte. All solid state batteries with non-flammable inorganic solid electrolytes come into the limelight due to its potential for securing higher energy density and safe characteristics over current lithium ion battery system.In this study, composite electrode sheet and cell fabrication technology was examined by slurry mixing coating technique. Cathode electrode sheets were obtained by coating slurries consisting of LiNi0.8Co0.1Mn0.1O2 as the active material, an argyrodite structure Li6PS5Cl solid electrolyte, conductive carbon, butadiene-based binder with solvent on carbon coated aluminum foil as the current collector. Homogeneous mixing and coating conditions were examined by controlling composition, kinds of binder in order to achieve optimal conduction pathway of lithium ion and electron. All solid state batteries were fabricated and evaluated both half-cell and full-cell type. Electrochemical tests were investigated and the detailed results will be discussed in this presentation.

Effects on Interfacial Resistance Using LICGCTM in the Cathode

Lithium ion batteries are widely used in electric devices and electric vehicles due to their excellent performance at high power and the high energy density they provide compared to other conventional batteries. The application for electric vehicles is expanding worldwide as our society moves towards a lower carbon footprint but the lithium ion battery technology still needs further improvements in terms of physical properties, output, durability and safety. Current lithium ion batteries also degrade with charge–discharge cycles and storage time. In the cathode, low retention capacity, accompanied by the growth of resistive thin films and crystal structure deterioration on the surface of the active materials, remain unsolved problems. Modifications to the cathode surfaces have been researched and proven as effective measures to improve durability. Surface coatings on lithium‐ion battery cathodes improve their durability. Solid oxide materials like MgO, ZrO2 and SiO2 are applied or processed on to the cathode active materials by sol-gel, PVD or mechanochemical treatments and the solid oxide layer plays a role as an artificial solid electrolyte interface. The solid oxide coating layer prevents contact between the electrolyte and the active materials thus inhibiting the redox process and leading to an improvement in the cycle performance of the battery.We confirmed the LCO cathode containing a small % of Ohara lithium ion glass ceramic (LICGCTM ) PW-01 powder showed less deterioration and transition metal reduction at high temperature (60℃). The LICGCTM PW-01 powder was produced using a glass melting and ceraming method. A Li 2O-Al 2O 3-TiO 2-P 2O 5 glass was prepared and converted into glass-ceramics through heat-treatment. The lithium ion conductivity of the glass-ceramic with Li 1 + x Al x Ti 2 − x (PO 4) 3 phase is extremely high 1 × 10 −3 Scm −1 at room temperature. We found that adding LICGCTM PW-01 powder in the cathode had other significant effects, including increasing the battery capacity at high rate and at low temperature (-20℃). We also verified via by EIS measurement that the LICGCTM PW-01 powder additive significantly reduced the charge transfer resistance. The use of the LICGCTM PW-01 powder as a cathode slurry additive can serve an important role in improving the performance of lithium ion batteries.

(Invited) Layer Design and Approach in New Energy Storage Materials

Current lithium-ion batteries (LIB) dominate its use as energy sources in the various applications from small to large sized-systems. Optimization of the cell design and densification of active materials worked effectively for the requirements for the portable electronic devices. However, current Li-ion system approaches limit in energy density for emerging applications. Thus, advanced LiBs and next generation batteries with new materials and cell designs are urgent and critical in both practical and academic aspects.Layer structure from coating, deposition, and passive formation by additives play a important platform technology in materials and components in the batteries. Thickness of the layers differs from nano to micrometer scales depending on the applied components. Systems related with layers for improving the flexible battery and lithium metal battery are discussed.

Uncovering the Relationship between Diameter and Height of Electrodeposited Lithium Protrusions in a Rigid Electrolyte

A promising approach for enabling rechargeable batteries with significantly higher energy densities than current lithium-ion batteries is by deploying lithium metal anodes. However, the growth of lithium protrusions during charging presents significant challenges. While solid electrolytes have the potential to solve this problem, protrusions grow in all electrolytes when the current density exceeds a critical value. Fundamentally understanding the formation is necessary to develop a rational approach for increasing the critical current density, but it is challenging due to the complex interplay between electrochemical and material properties. The diameters and heights of protrusions on lithium metal anodes stabilized by a rigid block copolymer electrolyte were measured in situ by synchrotron hard X-ray microtomography. The diameter of the shorting protrusions increased linearly with increasing electrolyte thickness. Further, a universal linear relationship between protrusion height and diameter of both shorting and non-shorting protrusions was observed. A model based on concentrated solution theory was used to establish the electrochemical and mechanical sources for our observations. Experiment and computation combine to give the counterintuitive result: the fastest-growing protrusions have the largest diameter.