Dual-ion Batteries Research Articles

Graphdiyne—A Two-Dimensional Cathode for Aluminum Dual-Ion Batteries with High Specific Capacity and Diffusivity

Graphdiyne—A Two-Dimensional Cathode for Aluminum Dual-Ion Batteries with High Specific Capacity and Diffusivity

Frontispiece: A TiSe2‐Graphite Dual Ion Battery: Fast Na‐Ion Insertion and Excellent Stability

Batteries A TiSe2-graphite Na dual-ion battery with fast kinetics was developed as described by Jie Shu, Bao-Lian Su et al. in the Communication on page 18430 by combining a TiSe2 Na-ion anode with an anion-storing graphite cathode.

A combinatorial study of electrochemical anion intercalation into graphite

Dual-ion batteries are considered to be an emerging viable energy storage technology owing to their safety, high power capability, low cost, and scalability. Intercalation of anions into a graphite positive electrode provides high operating voltage and improved energy density to such dual-ion batteries. In this work, we have performed a combinatorial study of graphite intercalation compounds considering four anions, namely hexafluorophosphate (PF), perchlorate (ClO), bis(fluorosulfonyl)imide (FSI−), and bis(trifluoromethanesulfonyl)imide (TFSI−), via first-principles calculations. The structural properties and energetics of the intercalation compounds are compared based on different sizes, geometries, and the physical and chemical properties of the intercalated anions. The staging mechanism of anion intercalation into graphite and the specific capacities, and voltage profiles of the intercalated compounds are investigated. A comparison regarding battery electrochemistry is also done with available experimental observations. Our calculated intercalation energies and voltage profiles show that the initial anion intercalation into graphite is less favorable than subsequent ones for all the anions considered in this study. Although the effect of the size of anions in a graphite cathode on various properties of the intercalated compounds is not as significant as the size of cations in a graphite anode, some distinction between the studied anions can still be made. Among the studied anions, the intercalation compounds based on PF are the most stable ones. These PF anions cause relatively small structural deformations of the graphite and have the highest oxidative ability, highest onset voltage, and highest diffusion barrier along the graphene sheets. The overall small diffusion barriers of the anions within graphite explain the high rate capability of dual-ion batteries.

A sustainable LiFePO4/graphite hybrid cathode capable of stepwise cation and anion storage

Dual ion battery (DIB) with graphite cathode is a renewable energy storage system but suffers from low capacity. Addition of lithium ion battery (LIB) cathode to graphite cathode not only facilitates capacity increment but also serves as proof-of-concept for LIB-DIB hybridization. In this study, a hybrid cathode, incorporating a physical mixture of high working potential graphite and nontoxic lithium iron phosphate (LiFePO4, LFP), is proposed and examined. The graphite interacts with anion and works as electrically conductive matrix. While additive LFP is active to cation, serving as capacity facilitator. Characterization results reveal that, during charging, the hybrid cathode starts with LFP delithiation in lower voltage region and finishes with anion intercalation in graphite at higher voltage region. During discharging, processes are reversed with stepwise anion deintercalation and cation insertion, without interfering individual constituent's proper functioning. The transfer of two polarity distinct ions inside the hybrid cathode maintains high independence, without any added kinetical difficulties. Such hybrid cathode is demonstrated to work stably with varied LFP-graphite proportions. The addition of 40 wt% LFP to graphite cathode shows doubled capacity and excellent long-term cyclability. And the hybrid cathode is also cyclable in a full cell configuration.

Combining Experiments and Theoretical Calculations to Investigate the Intercalation Behavior of Bis(trifluoromethanesulfonimide) Anion into Graphite Electrodes from Alkyl Phosphates.

In dual-ion batteries (DIBs) utilizing organic electrolyte solutions, the combinations of electrolyte salt and solvent serve as a determiner of the electrochemical performance of graphite electrode partially because solvent participates in the anion intercalation procedure. In this case, every solvated-anion@graphite intercalation compound possesses the characteristic intercalated gallery height. However, in Li/graphite DIBs with concentrated LiTFSI (lithium bis(trifluoromethanesulfonimide))-alkyl phosphates (ca. trimethyl, triethyl, tripropyl, tributyl phosphate) solutions, solvated-TFSI-@graphite intercalation compounds have the nearly identical intercalated gallery height of about 0.803 nm, which may be mainly attributed to both the big size of TFSI- anion and the rigid PO4 framework of these alkyl phosphate solvents.

Cation mixing in Wadsley-Roth phase anode of lithium-ion battery improves cycling stability and fast Li+ storage

Developing advanced electrode materials with high stability and high ion-diffusion rate is vital for the success of high-rate lithium-ion batteries (LIBs). However, the commonly used modification strategies such as carbon coating, nanoarchitecture engineering, and introducing oxygen vacancies are unavoidably meeting with the problems of high cost and complicated preparation process. Herein, we report cation-mixing effect enhanced fast Li+ storage in Wadsley-Roth phase Fe-Ti-Nb oxide (FTNO) materials by a facile solution combustion method. Co-existence of Fe3+ and Ti4+ in the crystallographic shear structure leads to enhanced cation-mixing effect with cations short-range order (SRO) in FTNO materials, thus resulting in outstanding capabilities of fast Li+ storage/diffusion, robust structure and low charge transfer resistance compared with the analogues of FeNb11O29 and Ti2Nb10O29. Consequently, a high-capacity retention of 71.8% is achieved upon 10 000 cycles at 10 C. Most importantly, the feasibilities of FTNO are also systematically verified in various practical electrochemical energy storage devices containing conventional lithium-ion full battery (FTNOǁLiFePO4), high-power lithium-ion hybrid capacitor [FTNOǁactive carbon (AC)], and novel dual-ion battery [FTNOǁmesocarbon microbeads (MCMB)]. It is worth noting that the FTNOǁMCMB with high output voltage of 3 V delivers a capacity of 105.7 mAh g−1, implying a great potential of FTNO applied in dual-ion batteries.

A COF-Like N-Rich Conjugated Microporous Polytriphenylamine Cathode with Pseudocapacitive Anion Storage Behavior for High-Energy Aqueous Zinc Dual-Ion Batteries.

Conducting polymers with good electron conductivity and rich redox functional groups are promising cathode candidates for constructing high-energy aqueous zinc batteries. However, the glaring flaw of active-site underutilization impairs their electrochemical performance. Herein, wereport a poriferous polytriphenylamine conjugated microporous polymer (CMP) cathode capable of accommodating Cl- anions in a pseudocapative-dominated manner for energy storage. Its specific 3D, covalent-organic-framework-like conjugated network ensures high accessibility efficacy of N active sites (up to 83.2% at 0.5 A g-1 ) and distinct physicochemical stability (87.6% capacity retention after 1000 cycles) during repeated charging/discharging courses. Such a robust CMP electrode also leads to a zinc dual-ion battery device with a high energy density of 236 W h kg-1 and a maximum power density of 6.8kW kg-1 , substantially surpassing most recently reported organic-based zinc batteries. This study paves the way for the rational design of advanced CMP-based organic cathodes for high-energy devices.

3-V class Mg-based dual-ion battery with astonishingly high energy/power densities in common electrolytes

The development of electrode materials with higher energy/power densities is crucial for magnesium batteries to become a viable alternative to lithium-ion batteries. Herein, we describe a possible solution that involves high-voltage redox polymer (poly(vinyl carbazole), PVCz) cathodes and alloy-type anodes (3Mg/Mg2Sn) in Mg(TFSI)2/acetonitrile (TFSI = bis(trifluoromethanesulfonyl)imide). When low molecular weight PVCz is crosslinked (x-PVCz), the density of micro-to-macro pores and the electronic conductivity are remarkably enhanced, which enables the attainment of near theoretical capacities (122 mAh g−1) with a marginal voltage drop even at a rate of 2000 mA g−1 (14.3C). This corresponds to energy and power densities of 384 Wh kg−1 and 6300 W kg−1, respectively, which are incomparably high values for magnesium batteries. Their cyclic stability also is excellent, delivering 94.2% of the initial capacity during 2000 charge/discharge cycles. Magnesium-based dual ion batteries (MDIBs), which consist of de-magnesiated 3Mg/Mg2Sn anodes and x-PVCz cathodes in Mg(TFSI)2/acetonitrile, also retain the unique properties of x-PCVz. The discharge voltages are slightly decreased due to an alloy/de-alloy potential of 3Mg/Mg2Sn, but high energy/power densities and excellent cyclability are maintained. This work evidences the excellence of x-PVCz and hints the usefulness of MDIBs for the construction of viable magnesium batteries.

Microwave-Assisted Expanded Graphite as a Long Cyclic Cathode for the Lithium Dual-Ion Battery.

Lithium metal (Li) has been recognized as a promising anode for most energy storage devices, owing to its high theoretical capacity. Nevertheless, Li anode present serious safety hazards and have a rapidly fading capacity, which limits its practical applications. Herein, a lithium-expanded graphite dual-ion battery (Li-EG DIB) was developed by combining a Li metal sheet as an anode with expanded graphite (EG) as a cathode. EG was produced by microwave (MW) photons energy (~1 × 10-5 eV) at different time durations (15, 30, 45, and 60 s) to allow moderate expansion between the graphite sheets and the removal of the surface functional groups that encourage the intercalation and de-intercalation of the ions; consequently, the capacity was improved. The MW-EG samples were characterized by X-ray powder diffraction (XRD), Raman spectroscopy, and Fourier transform infrared spectrophotometry (FT-IR). The EG synthesized at 45 s in MW exhibited a high capacity and a stable and long cycling life. The charge capacity of the Li-EG-45 DIB after 500 cycles at 0.05 Ag-1 was 20.3 mAh g-1 in the voltage window of 2-5 V. It is worth noting that the EG-45 electrode showed ~100% capacity retention, even after the rate test.

Dual‐Ion Batteries: High Oxidation Potential ≈6.0 V of Concentrated Electrolyte toward High‐Performance Dual‐Ion Battery (Adv. Energy Mater. 25/2021)

In article number 2100151, Yongbing Tang and co-workers develop a 4.0 m LiFSI/TMS high-concentration and high-voltage electrolyte, which shows significantly suppressed gas formation and enhanced anion intercalation reversibility under high working voltages. Based on this electrolyte system, the dual-ion battery (DIB) exhibits much improved electrochemical performance. This work provides an effective approach to improve the performance of DIBs.

A TiSe2‐Graphite Dual Ion Battery: Fast Na‐Ion Insertion and Excellent Stability

AbstractThe sodium dual ion battery (Na‐DIB) technology is proposed as highly promising alternative over lithium‐ion batteries for the stationary electrochemical energy‐storage devices. However, the sluggish reaction kinetics of anode materials seriously impedes their practical implementation. Herein, a Na‐DIB based on TiSe2‐graphite is reported. The high diffusion coefficient of Na‐ions (3.21×10−11–1.20×10−9 cm2 s−1) and the very low Na‐ion diffusion barrier (0.50 eV) lead to very fast electrode kinetics, alike in conventional surface capacitive storage systems. In‐situ investigations reveal that the fast Na‐ion diffusion involves four insertion stage compositions. A prototype cell shows a reversible capacity of 81.8 mAh g−1 at current density of 100 mA g−1, excellent stability with 83.52 % capacity retention over 200 cycles and excellent rate performance, suggesting its potential for next‐generation large scale high‐performance stationary energy storage systems.

A TiSe2‐Graphite Dual Ion Battery: Fast Na‐Ion Insertion and Excellent Stability

AbstractThe sodium dual ion battery (Na‐DIB) technology is proposed as highly promising alternative over lithium‐ion batteries for the stationary electrochemical energy‐storage devices. However, the sluggish reaction kinetics of anode materials seriously impedes their practical implementation. Herein, a Na‐DIB based on TiSe2‐graphite is reported. The high diffusion coefficient of Na‐ions (3.21×10−11–1.20×10−9 cm2 s−1) and the very low Na‐ion diffusion barrier (0.50 eV) lead to very fast electrode kinetics, alike in conventional surface capacitive storage systems. In‐situ investigations reveal that the fast Na‐ion diffusion involves four insertion stage compositions. A prototype cell shows a reversible capacity of 81.8 mAh g−1 at current density of 100 mA g−1, excellent stability with 83.52 % capacity retention over 200 cycles and excellent rate performance, suggesting its potential for next‐generation large scale high‐performance stationary energy storage systems.

Molecular Coupling and Self-Assembly Strategy toward WSe2 /Carbon Micro-Nano Hierarchical Structure for Elevated Sodium-Ion Storage.

Sodium (Na) ion-based dual-ion batteries (Na-DIBs) have attracted great attention, owing to their benefits of low cost, high working voltage, and environmental friendliness. However, the limited capacity and low tap density of currently reported anode materials restrict the further improvement of Na-DIBs. Herein, a micro-nano structure with vertically aligned WSe2 nanoflakes anchored tightly on a micron-sized carbon sphere (WSe2 /CS) is successfully constructed via combining the molecular coupling and self-assembly strategy. Within this hierarchical structure, the WSe2 nanoflakes can shorten the diffusion path for Na+ ions and alleviate structural deformation during the charge/discharge process; meanwhile, the micron-sized carbon core provides conductive support and helps improve the total tap density of the anode electrode. As a result, this micron-sized WSe2 /CS displays a high specific capacity of ≈252.8mAhg-1 and good cycling performance with ≈92% capacity retention after 1200 cycles. Moreover, by pairing this WSe2 /CS anode with environmental friendly graphite as cathode, a proof-of-concept Na-DIB shows 85.6% capacity retention after 1000 cycles, which is among the best performances of previously reported Na-DIBs.

A Metal-free ionic liquid Dual-ion battery based on the reversible interaction of 1-Butyl-1-Methylpyrrolidinium cations with 1,4,5,8-Naphthalenetetracarboxylic dianhydride

The strong self-discharge reaction is one of the key factors limiting the practical use of dual-ion batteries, which leads to low coulombic efficiency and discharge capacity loss. It is of great significance to effectively reduce the self-discharge effect through redox reactions between organic electrodes and electrolytes. Herein, a dual-ion battery study that uses 1,4,5,8-naphthalenetetracarboxylic dianhydride as the anode and 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide as the electrolyte is conducted. Due to the introduction of organic materials, the storage mechanism of cations on the anode is changed, which weakens the self-discharge effect. The battery shows a low self-discharge rate of 6.12% h−1 and a high discharge capacity of 114 mAh g−1. The voltage declines by only 0.14 V after resting for 15 h due to the strong redox reaction between Pyr14+ cations and the CO groups of NTCDA. Meanwhile, a double-layer filter paper system with small porosity is used to improve the cycle performance of the battery.

Natural Activation of CuO to CuCl2 as a Cathode Material for Dual-Ion Lithium Metal Batteries

To meet the rising energy demand for rapidly advancing battery-driven devices, a novel Li/Cl dual-ion battery chemistry based on non-flammable SO2-in-salt electrolyte is receiving significant attention. Herein, we propose a natural-activable CuO hollow nanocube (HNC) cathode material for dual-ion Li metal batteries using SO2-in-salt electrolyte. Natural activation is achieved via spontaneous chlorination of CuO HNCs into an electrochemically active CuCl2 phase upon immersed in a SO2-in-salt electrolyte. The on-site conversion reactions are proposed with the support of thermodynamic calculations; the phase transformations of active materials are confirmed through X-ray diffraction, X-ray photoelectron spectroscopy, and field emission scanning electron microscopy. As a solution to alleviate the volume expansion after chlorination, the HNC structure of CuO allows the resulting CuCl2 cathode material to deliver a reversible capacity up to 262.2 mAh g−1 (894.2 Wh kgCuO−1) with stable cycle performance over 150 cycles. The Li-CuO battery system presented here demonstrates the feasibility of non-flammable, high-energy density Li/Cl dual-ion Li metal batteries as a potential alternative to currently used lithium ion batteries.

Graphitic biogas-derived nanofibers as cathodes for sodium dual-ion batteries: Intercalation of PF6− anions

The electrochemical intercalation of PF6− anions into graphitic nanomaterials of renewable origin with different degrees of structural order to be subsequently used as cathodes for sodium dual-ion batteries is herein investigated for the first time. Overall, the electrochemical performance of the biogas-derived carbon nanofibers depends on their graphitic structure, specifically on crystallite height which was found to be the determining parameter for the scope of electrochemical intercalation of PF6− anions into these nanomaterials.

Well-dispersed Sb2O3 nanoparticles encapsulated in multi-channel-carbon nanofibers as high-performance anode materials for Li/dual-ion batteries

Reasonable design and construction of electrode materials with high-performance and low-cost are essential for Li-ion batteries (LIBs) and dual-ion batteries (DIBs). Herein, an eco-friendly and facile strategy is proposed to encapsulate Sb2O3 nanoparticles in one-dimensional (1D) multi-nanochannel-containing carbon nanofibers (Sb2O3@MCNF) using the electrospinning method as well as the subsequent calcination. Such unique construction not only effectively reduces the large volume variation during cycling, but also achieves the fast Li+/e− transportation. As a result, the optimized sample with the precursor triphenylantimony (III) content of 0.35 g (Sb2O3@MCNF-0.35) exhibits superior electrochemical performance as anode materials for LIBs and Li-based DIBs (LDIBs), including high reversible capacity (~333.5 mAh g−1 at 1 A g−1 for LIBs and 233.5 mAh g−1 at 0.2 A g−1 for LDIBs) and favorable cycling stability (over 800 cycles for LIBs and 100 cycles for LDIBs). These results demonstrate that the well-designed Sb2O3@MCNF-0.35 can availably boost the electrochemical performance, which provides vast potential for applications in the field of high-performance energy storage equipment.

Conversion/insertion pseudocapacitance-driven vacancy defective perovskite fluorides K0.82Co0.43Mn0.57F2.66@reduced graphene oxide anode for powerful Na-based dual-ion batteries and capacitors

Na-based dual-ion batteries (Na-DIBs) and capacitors (NICs) have received particular attention in the recent years because of the advantages of simple design, environmentally friendly, feasibility, and low cost, etc. Herein, we report a new vacancy defective perovskite fluorides K0.82Co0.43Mn0.57F2.66@reduced graphene oxide (KCMF(1-1)@rGO) nanocrystal as a promising anode material for Na-DIBs and NICs, showing the pseudocapacitance-dominated conversion-insertion hybrid mechanisms. Thanks for the synergistic effect of Co/Mn active species, the fast kinetics of pseudocapacitive behavior, the improved ion storage ability of K-ion vacancy, and the unique K0.82Co0.43Mn0.57F2.66@rGO nano-heterostructures, the KCMF(1-1)@rGO anode exhibits superior specific capacity, rate and cycling behavior (176-84 mAh g−1 at 0.05-1 A g−1, 67 % retention/500 cycles/0.3 A g−1). Furthermore, the designed Na-DIBs and NICs with the KCMF(1-1)@rGO anode and graphite (KS6)/activated carbon (AC) as cathodes demonstrate remarkable performance, showing the 145.9 Wh kg−1/0.83 kW kg−1/60%/1000 cycles/5 A g−1 and 66.51~29 Wh kg−1/0.53~16.84 kW kg−1/81%/1000 cycles/5 A g−1 for the KCMF(1-1)@rGO//KS6 Na-DIBs and KCMF(1-1)@rGO//AC NICs respectively, indicating a promising application for Na-ion energy storage.

Current Collector-Free Reduced Graphene Oxide Aerogel Cathode for High Energy Density Dual-Ion Batteries.

As an important indicator to evaluate battery performance, the energy density of commercial lithium ion batteries is close to the limit. Herein, for the first time, we reported that the reduced oxide graphene (rGO) aerogel can be directly used for the cathode of a dual-ion battery to achieve a superior specific energy density by reducing the dead weight of the battery. The porous structure of an rGO aerogel facilitates the penetration of the electrolyte and provides more active sites for energy storage. At the same time, the continuous graphene network benefits the electron transport. The lithium-rGO battery shows a discharge specific capacity of 94 mA h g-1 at 1 A g-1 and a superior specific energy density of 213 W h kg-1 at 2141 W kg-1. It is worth noting that this current collector-free electrode design would promote the development and application of graphene-based batteries with a high energy density.

Novel Polyamine-Based Cathodes for Dual-Ion Batteries

For decades, the design of energy storage devices constantly faces new challenges associated with the growing demand for portable electronics, electric vehicles and smart grids. [1] In particular, there is an urgent need for development of inexpensive, stable and high-power batteries which are capable to operate without significant capacity losses in charge-discharge cycles. The widespread installation of such devices in the stationary energy storage systems for power plants would allow to create a sustainable smart grid ecosystem.Dual-ion batteries (DIB) is a special type of energy storage devices in which both cations and anions are involved in redox processes. DIB represent one of the most promising post-lithium technology for stationary energy storage due to their relatively high energy density, rate capabilities and low cost. For the low cost of materials, dual-carbon batteries (DCB), in which both electrodes are presented by carbon materials, is the most popular and well-studied type of DIB. [2] Nevertheless, DCB have significant drawbacks such as low specific capacity of the cathode material (<110 mAh/g), [3] and high operation voltages (>5V) [2,3] leading to rapid electrolyte degradation.Among the variety of advanced cathode materials for dual-ion batteries, we consider polymeric aromatic amines as the most promising ones for its outstanding performance characteristics. In particular, the materials of this type show optimal values of redox potential (3-4 V vs. Li+/Li), [4] high values of specific capacity (up to 223 mAh/g), [5] and extremely high current rates available for battery charge and discharge (up to 300C). [6] In the present work, we report synthesis and a comprehensive study of a large group of polymeric aromatic amines as active cathode materials for dual-ion batteries with high theoretical specific capacities (>160 mAh/g). Within the framework of the research project, the cathode materials for ultrafast lithium-based and high-energy potassium-based dual-ion batteries were developed. In particular, the polyamine-based organic cathodes with impressive rate capabilities delivering specific capacities of up to 84 mAh/g at 100C current rate in lithium batteries were designed. [7] The use of cheaper and concentrated potassium-based electrolyte (2.2 M KPF6 in diglyme) allowed us to assemble potassium dual-ion batteries with the cathode energy densities of up to 593 Wh/kg, while poly(N-phenyl-5,10-dihydrophenazine) was applied as an active material. [8] Another significant step towards the dual-ion batteries with improved performance was made by increasing of active material content to impressive for organic cathodes 80%, while poly(diphenylamine) and multi-walled carbon nanotubes were applied as an active material and carbon filler, respectively.This study was financially supported by the Russian Foundation for Basic Research, project 19-33-90233.