Advanced K3V2(PO4)2O2F cathode for rechargeable potassium-ion batteries with high energy density

Applied Physics Letters, Journal Year: 2024, Volume and Issue: 124(18)

Published: April 29, 2024

Potassium-ion batteries (PIBs) have emerged as promising candidates for cost-effective and sustainable energy-storage systems. Nevertheless, limited by the large K+ radius, PIBs great difficulty in figuring out designing suitable host materials. Herein, a cathode material K3V2(PO4)2O2F (KVPOF) has been carefully prepared. It exhibits high specific capacity close to theoretical value, 116.3 mAh/g at 20 mA/g within voltage window of 2.0–4.5 V vs K+/K, corresponding de-/intercalation process ∼2 mol per formula unit. In addition, it presents an average operating plateau about 3.5 V, resulting energy density 410 Wh/kg. The crystal structure phase transition are revealed situ x-ray diffraction, is found be fully reversible during K+. Furthermore, potential KVPOF applications low temperatures was explored, full cell matched with graphite anode demonstrated fair electrochemical performance. experimental results suggest feasibility using rechargeable PIBs.

Language: Английский

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Prospects and Challenges of Practical Nonaqueous Potassium‐Ion Batteries

Advanced Functional Materials, Journal Year: 2024, Volume and Issue: unknown

Published: July 18, 2024

Abstract Over the past decade, concerns over sustainability of lithium‐ion batteries (LIBs) have arisen due to scarcity critical elements such as lithium (Li), nickel (Ni), and cobalt (Co), prompting exploration alternative complementary electrochemical energy storage technologies. Due more abundant resources compared contemporary LIBs potentially higher specific than emerging sodium‐ion (SIBs), potassium‐ion (PIBs) attracted intensive research interest a promising existing Nevertheless, development practical PIBs remains in its infancy. In this perspective, various electrode materials electrolytes reported for from an application point view identifying most ones with high are first concisely discussed. Then, pack‐level energy, density, cost analyses presented several chemistries, which also representative SIBs demonstrate advantages PIBs. After that, succinct discussion is evaluate practicality potassium metal batteries. Finally, challenges associated commercialization PIBs, providing future fronts high‐performance outlined.

Language: Английский

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Chloro‐Functionalized Ether‐Based Electrolyte for High‐Voltage and Stable Potassium‐Ion Batteries

Angewandte Chemie, Journal Year: 2024, Volume and Issue: 136(23)

Published: April 10, 2024

Abstract Ether‐based electrolyte is beneficial to obtaining good low‐temperature performance and high ionic conductivity in potassium ion batteries. However, the dilute ether‐based electrolytes usually result ion‐solvent co‐intercalation of graphite, poor cycling stability, hard withstand voltage cathodes above 4.0 V. To address aforementioned issues, an electron‐withdrawing group (chloro‐substitution) was introduced regulate solid‐electrolyte interphase (SEI) enhance oxidative stability electrolytes. The (~0.91 M) chloro‐functionalized not only facilitates formation homogeneous dual halides‐based SEI, but also effectively suppress aluminum corrosion at voltage. Using this functionalized electrolyte, K||graphite cell exhibits a 700 cycles, K||Prussian blue (PB) (4.3 V) delivers 500 PB||graphite full‐cell reveals long 6000 cycles with average Coulombic efficiency 99.98 %. Additionally, can operate under wide temperature range from −5 °C 45 °C. This work highlights positive impact functionalization on electrochemical performance, providing bright future application for long‐lasting, wide‐temperature, PIBs beyond.

Language: Английский

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Ultrathin K–C Composite Anode Enables Conformal Stripping/Plating for Dendrite-Free and High-Rate Potassium-Metal Batteries

ACS Energy Letters, Journal Year: 2024, Volume and Issue: 9(9), P. 4534 - 4543

Published: Aug. 23, 2024

The development of metallic K is seriously hampered by low melting point, high reactivity, and uncontrollable dendrite growth. Herein, benefiting from the super-potassiophility CNTs (carbon nanotubes), K@CNT composite anodes are prepared via a rational fused-modeling approach, where build interconnected frameworks atoms anchored on CNTs, inducing depressed atomic creeping flowability at temperatures. Thereby, deliver flexibility, processability (∼30 μm), thermal stability (up to 300 °C). In particular, exhibit conformal stripping plating behavior along with plane-structure CNT framework during charge–discharge processes under 10 mA cm–2 without dendrites. Moreover, // Prussian white full cells rate performance (60.9 mAh g–1 3000 g–1), energy density (187.3 Wh kg–1), high-temperature stability. This work provides an avenue for designing high-performance driving commercialization K-metal batteries.

Language: Английский

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K_xVPO₄F (x∼0): A New High‐Voltage and Low‐Stain Cathode Material for Ultrastable Calcium Rechargeable Batteries

Advanced Energy Materials, Journal Year: 2024, Volume and Issue: 14(11)

Published: Jan. 14, 2024

Abstract The utilization of high‐voltage intercalation cathodes in calcium‐ion batteries (CIBs) is impeded by the substantial size and divalent character Ca 2+ ions, which result pronounced volume alterations sluggish ion mobility, consequently causing inferior reversibility low energy/power densities. To tackle these issues, polyanionic K‐vacant K x VPO 4 F (x∼0, designated as 0 VPF) proposed ultra‐stable cathode material CIBs. VPF demonstrates a decent calcium storage capacity 75 mAh g −1 at 10 mA remarkable retention 84.2% over 1000 cycles. average working voltage 3.85 V versus /Ca, representing highest value reported for CIB to date. combined experimental theoretical investigations revealed that changes hopping diffusion barriers contribute extraordinary stability high‐power capabilities, respectively, VPF. distribution ions into frameworks with spatial separation effectively attenuates –Ca repulsive force thus augmenting migration kinetics. high attributed inductive effect from largely electronegative fluorine. In conjunction metal anode compatible electrolyte, full cells featured record‐high energy density ≈300 Wh kg .

Language: Английский

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