In this work, combining both advantages of potassium‐ion batteries and dual‐ion batteries, a novel potassium‐ion‐based dual‐ion battery (named as K‐DIB) system is developed based on a potassium‐ion ...electrolyte, using metal foil (Sn, Pb, K, or Na) as anode and expanded graphite as cathode. When using Sn foil as the anode, the K‐DIB presents a high reversible capacity of 66 mAh g−1 at a current density of 50 mA g−1 over the voltage window of 3.0–5.0 V, and exhibits excellent long‐term cycling performance with 93% capacity retention for 300 cycles. Moreover, as the Sn foil simultaneously acts as the anode material and the current collector, dead load and dead volume of the battery can be greatly reduced, thus the energy density of the K‐DIB is further improved. It delivers a high energy density of 155 Wh kg−1 at a power density of 116 W kg−1, which is comparable with commercial lithium‐ion batteries. Thus, with the advantages of environmentally friendly, cost effective, and high energy density, this K‐DIB shows attractive potential for future energy storage application.
A novel dual‐ion battery based on potassium‐ion electrolyte (K‐DIB) is developed in this work using metal foil as both anode and current collector and expanded graphite as cathode. The K‐DIB based on Sn foil anode presents a capacity of 66 mAh/g over 3.0–5.0 V, and exhibits a capacity retention of 93% after 300 cycles. Moreover, it delivers a energy density of 155 Wh/kg at a power density of 116 W/kg, comparable with commercial lithium‐ion batteries.
Rechargeable sodium/potassium‐ion batteries (SIBs/PIBs) with abundant reserves of Na/K and low cost have been a promising substitution to commercial lithium‐ion batteries. As for pivotal anode ...materials, metal sulfides (MSx) exhibit an inspiring potential due to the multitudinous redox storage mechanisms for SIBs/PIBs applications. Nevertheless, they still confront several bottlenecks, such as the low electrical conductivity, poor ionic diffusivity, sluggish interfacial/surface reaction kinetics, and severe volume expansion, which distinctly restrain the battery performance. Meanwhile, the systematic insights into the design strategies of MSx for SIBs/PIBs have been seldom elaborated. In this review, the energy storage mechanism, challenge, and design strategies of MSx for SIBs/PIBs are expounded to address the above predicaments. In particular, design strategies of MSx are highlighted from the aspects of morphology modifications involving 1D/2D/3D configurations, atomic‐level engineering containing heteroatom doping, vacancy creation, and interlayer spacing expansion, and MSx composites with other MSx, metal oxides, carbonaceous, and graphite materials to boost the comprehensive electrochemical performance of SIBs/PIBs. Furthermore, prospects are presented for the further advance of MSx to surmount imminent challenges, hoping to forecast feasible future orientations in this field.
Design strategies of metal sulfides are proposed from the aspects of morphology modifications involving 1D/2D/3D configurations, atomic‐level engineering containing heteroatom doping, vacancy creation, and interlayer spacing expansion, and MSx composites with other MSx, metal oxides, carbonaceous and graphite materials to boost the comprehensive electrochemical performance of sodium/potassium‐ion batteries.
Due to the large abundance, low redox potential, and multivalent properties of calcium (Ca), Ca‐ion batteries (CIBs) show promising prospects for energy storage applications. However, current ...research on CIBs faces the challenges of unsatisfactory cycling stability and capacity, mainly restricted by the lack of suitable electrolytes and electrode materials. Herein, we firstly developed a 3.5 m concentrated electrolyte with a calcium bis(fluorosulfonyl)imide (Ca(FSI)2) salt dissolved in carbonate solvents. This electrolyte significantly improved the intercalation capacity for anions in the graphite cathode and contributed to the reversible insertion of Ca2+ in the organic anode. By combining this concentrated electrolyte with the low‐cost and environmentally friendly graphite cathode and organic anode, the assembled Ca‐based dual‐ion battery (Ca‐DIB) exhibits 75.4 mAh g−1 specific discharge capacity at 100 mA g−1 and 84.7 % capacity retention over 350 cycles, among the best results known for CIBs.
Ca‐ion battery: Ascribed to the improved anion intercalation performance in the graphite cathode and reversible Ca2+ insertion in the organic anode, by combining a 3.5 m concentrated Ca‐ion electrolyte with the low‐cost and environmentally friendly graphite cathode and organic anode, the proof‐of‐concept Ca‐based dual‐ion battery exhibits 75.4 mAh g−1 specific discharge capacity and 84.7 % capacity retention over 350 cycles, among the best results for Ca‐ion batteries.
A 3D porous Al foil coated with a uniform carbon layer (pAl/C) is prepared and used as the anode and current collector in a dual‐ion battery (DIB). The pAl/C‐graphite DIB demonstrates superior ...cycling stability and high rate performance, achieving a highly reversible capacity of 93 mAh g−1 after 1000 cycles at 2 C over the voltage range of 3.0–4.95 V. In addition, the DIB could achieve an energy density of ≈204 Wh kg−1 at a high power density of 3084 W kg−1.
Potassium-ion batteries are a compelling technology for large scale energy storage due to their low-cost and good rate performance. However, the development of potassium-ion batteries remains in its ...infancy, mainly hindered by the lack of suitable cathode materials. Here we show that a previously known frustrated magnet, KFeC
O
F, could serve as a stable cathode for potassium ion storage, delivering a discharge capacity of ~112 mAh g
at 0.2 A g
and 94% capacity retention after 2000 cycles. The unprecedented cycling stability is attributed to the rigid framework and the presence of three channels that allow for minimized volume fluctuation when Fe
/Fe
redox reaction occurs. Further, pairing this KFeC
O
F cathode with a soft carbon anode yields a potassium-ion full cell with an energy density of ~235 Wh kg
, impressive rate performance and negligible capacity decay within 200 cycles. This work sheds light on the development of low-cost and high-performance K-based energy storage devices.
Redox‐active organics are investigation hotspots for metal ion storage due to their structural diversity and redox reversibility. However, they are plagued by limited storage capacity, sluggish ion ...diffusion kinetics, and weak structural stability, especially for K+ ion storage. Herein, we firstly reported the lamellar tetrapotassium pyromellitic (K4PM) with four active sites and large interlayer distance for K+ ion storage based on a design strategy, where organics are constructed with the small molecular mass, multiple active sites, fast ion diffusion channels, and rigid conjugated π bonds. The K4PM electrode delivers a high capacity up to 292 mAh g−1 at 50 mA g−1, among the best reported organics for K+ ion storage. Especially, it achieves an excellent rate capacity and long‐term cycling stability with a capacity retention of ≈83 % after 1000 cycles. Incorporating in situ and ex‐situ techniques, the K+ ion storage mechanism is revealed, where conjugated carboxyls are reversibly rearranged into enolates to stably store K+ ions. This work sheds light on the rational design and optimization of organic electrodes for efficient metal ion storage.
The lamellar tetrapotassium pyromellitic (K4PM) for a K‐organic battery delivers a high capacity and excellent cycling robustness due to its four K+ ion storage sites and large layer distance with reversible rearrangement of conjugated carboxyls into enolates.
Potassium‐based dual ion batteries (K‐DIBs) with potassium cation (K+) intercalation graphitic anodes have been investigated for their potential in large‐scale energy storage applications owing to ...their merits of low cost and environmental friendly. Nonetheless, graphite anodes are plagued by volume expansion from the large K+ ions and the co‐intercalation of solvent molecules during the charging. Accordingly, organic materials stand out for the flexible adjustable structures and abundant active sites, which can accommodate cations by multiple functional groups without structural collapse. However, K‐DIBs based on organic anodes have rarely been investigated. Herein, 3D porous dipotassium terephthalate nanosheets are synthesized via a freeze‐dry method as the K‐DIB anode, which can reversibly store K+ ions at a fast rate with a high specific capacity and robust stability due to the sufficient redox active sites and diffusion pathways of K+ ions in the 3D porous structure. Consequently, a novel K‐DIB configuration combining this fast kinetics organic anode and environmental friendly expanded graphite (EG) cathode is constructed (pK2TP//EG), which exhibits a high specific capacity (68 mAh g‐1 at 2 C), good rate performance up to 20 C, and long cycling life with a capacity retention ~100% after 2000 cycles, which is the best performance observed among reported K‐DIBs.
A novel potassium‐based dual‐ion battery configuration combining a 3D porous dipotassium terephthalate nanosheets anode and environment friendly expanded graphite cathode is constructed, which exhibits good rate performance up to 20 C, and a long cycling life with a capacity retention ≈100% after 2000 cycles.
Abstract
Sodium-based dual-ion batteries (Na-DIBs) show a promising potential for large-scale energy storage applications due to the merits of environmental friendliness and low cost. However, ...Na-DIBs are generally subject to poor rate capability and cycling stability for the lack of suitable anodes to accommodate large Na+ ions. Herein, we propose a molecular grafting strategy to in situ synthesize tin pyrophosphate nanodots implanted in N-doped carbon matrix (SnP2O7@N-C), which exhibits a high fraction of active SnP2O7 up to 95.6 wt% and a low content of N-doped carbon (4.4 wt%) as the conductive framework. As a result, this anode delivers a high specific capacity ∼400 mAh g−1 at 0.1 A g−1, excellent rate capability up to 5.0 A g−1 and excellent cycling stability with a capacity retention of 92% after 1200 cycles under a current density of 1.5 A g−1. Further, pairing this anode with an environmentally friendly KS6 graphite cathode yields a SnP2O7@N-C||KS6 Na-DIB, exhibiting an excellent rate capability up to 30 C, good fast-charge/slow-discharge performance and long-term cycling life with a capacity retention of ∼96% after 1000 cycles at 20 C. This study provides a feasible strategy to develop high-performance anodes with high-fraction active materials for Na-based energy storage applications.
High-fraction active material (95.6 wt%) implanted in nitrogen-doped carbon matrix is designed for sodium-based dual-ion batteries with superior rate performance and long-term cycling life.
Abstract
Sodium-based dual-ion batteries have received increased attention owing to their appealing cell voltage (i.e., >3 V) and cost-effective features. However, the development of high-performance ...anode materials is one of the key elements for exploiting this electrochemical energy storage system at practical levels. Here, we report a source-template synthetic strategy for fabricating a variety of nanowire-in-nanotube MS
x
Te
y
@C (M = Mo, W, Re) structures with an in situ-grown carbon film coating, termed as nanocables. Among the various materials prepared, the MoS
1.5
Te
0.5
@C nanocables are investigated as negative electrode active material in combination with expanded graphite at the positive electrode and NaPF
6
-based non-aqueous electrolyte solutions for dual-ion storage in coin cell configuration. As a result, the dual-ion lab-scale cells demonstrate a prolonged cycling lifespan with 97% capacity retention over 1500 cycles and a reversible capacity of about 101 mAh g
−1
at specific capacities (based on the mass of the anode) of 1.0 A g
−1
and 5.0 A g
−1
, respectively.
The electrochemical performances of lithium-ion batteries(LIBs) are closely related to the interphase between the electrode materials and electrolytes. However, the development of lithium-ion ...batteries is hampered by the formation of uncontrollable solid electrolyte interphase(SEI) and subsequent potential safety issues associated with dendritic formation and cell short-circuits during cycling. Fabricating artificial SEI layer can be one promising approach to solve the above issues. This review summarizes the principles and methods of fabricating artificial SEI for three types of main anodes: deposition-type(
e.g.
, Li), intercalation-type(
e.g.
, graphite) and alloy-type(
e.g.
, Si, Al). The review elucidates recent progress and discusses possible methods for constructing stable artificial SEIs composed of salts, polymers, oxides, and nanomaterials that simultaneously passivate anode against side reactions with electrolytes and regulate Li
+
ions transport at interfaces. Moreover, the reaction mechanism of artificial SEIs was briefly analyzed, and the research prospect was also discussed.
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