3D Honeycomb Architecture Enables a High‐Rate and Long‐Life Iron (III) Fluoride–Lithium Battery

Abstract

Lithium-ion (Li-ion) batteries as one of the most popular energy storage systems have been widely used in laptops, mobile phones, cameras, electric tools, and cars. However, the commercial Li-ion batteries employing Ni-and Co-based intercalation-type cathodes with limited capacities and energy densities cannot meet the rapidly rising market demands in Metal fluoride-lithium batteries with potentially high energy densities, even higher than lithium-sulfur batteries, are viewed as very promising candidates for next-generation lightweight and low-cost rechargeable batteries. However, so far, metal fluoride cathodes have suffered from poor electronic conductivity, sluggish reaction kinetics and side reactions causing high voltage hysteresis, poor rate capability, and rapid capacity degradation upon cycling. Herein, it is reported that an FeF 3 @C composite having a 3D honeycomb architecture synthesized by a simple method may overcome these issues. The FeF 3 nanoparticles (10-50 nm) are uniformly embedded in the 3D honeycomb carbon framework where the honeycomb walls and hexagonal-like channels provide sufficient pathways for the fast electron and Li-ion diffusion, respectively. As a result, the as-produced 3D honeycomb FeF 3 @C composite cathodes even with high areal FeF 3 loadings of 2.2 and 5.3 mg cm −2 offer unprecedented rate capability up to 100 C and remarkable cycle stability within 1000 cycles, displaying capacity retentions of 95%-100% within 200 cycles at various C rates, and ≈85% at 2C within 1000 cycles. The reported results demonstrate that the 3D honeycomb architecture is a powerful composite design for conversion-type metal fluorides to achieve excellent electrochemical performance in metal fluoride-lithium batteries.

Designing Atomic Active Centers for Hydrogen Evolution Electrocatalysts

“…[88][89][90][91][92] Thee xcellent conductivity as well as the facilely tuned pore characteristics and physicochemical properties of carbon-based supports accelerate the mass transport and gas diffusion kinetics. [93][94][95][96][97][98] Furthermore,t he combination of metal atoms and non-carbon supports generates more potential active centers for the HER. [99] At present, M-N x ,M-C x etc.…”

“…The strong metal–support interactions not only immobilize the metal atoms on the supports to influence the coordination configurations, but also modulate the electron transfer and adsorption/desorption behavior [88–92] . The excellent conductivity as well as the facilely tuned pore characteristics and physicochemical properties of carbon‐based supports accelerate the mass transport and gas diffusion kinetics [93–98] . Furthermore, the combination of metal atoms and non‐carbon supports generates more potential active centers for the HER [99] .…”

Design aktiver atomarer Zentren für HER‐Elektrokatalysatoren

“…[88][89][90][91][92] Sowohl die ausgezeichnete Leitfähigkeit, die Tr äger auf Kohlenstoffbasis bieten, als auch die leicht einstellbaren Eigenschaften ihrer Poren und ihre physikochemischen Eigenschaften beschleunigen den Massentransport sowie die Kinetik der Gasdiffusion. [93][94][95][96][97][98] Im Übrigen erzeugt die Kombination von Metallatomen mit Nicht-Kohlenstoffträgern mehr potentielle aktive Zentren fürd ie HER. [99] Gegenwärtig haben sich M-N x ,M -C x usw.…”

“…Die starken Wechselwirkungen zwischen den aktiven Metallatomen und dem Träger immobilisieren die Metallatome, wodurch die Koordinationskonfiguration beeinflusst wird, und bestimmen den Prozess der Elektronenübertragung sowie das Adsorptions‐/Desorptionsverhalten [88–92] . Sowohl die ausgezeichnete Leitfähigkeit, die Träger auf Kohlenstoffbasis bieten, als auch die leicht einstellbaren Eigenschaften ihrer Poren und ihre physikochemischen Eigenschaften beschleunigen den Massentransport sowie die Kinetik der Gasdiffusion [93–98] . Im Übrigen erzeugt die Kombination von Metallatomen mit Nicht‐Kohlenstoffträgern mehr potentielle aktive Zentren für die HER [99] .…”

MOF-Derived Co3O4 Polyhedrons as Efficient Polysulfides Barrier on Polyimide Separators for High Temperature Lithium–Sulfur Batteries

“…It is generally known that both the electrode materials and the separators play vital roles in achieving safe and high energy density batteries. Cathode materials with multi-electron charge transfer processes could deliver higher specific capacity and thus higher energy density [6,7,8]. Lithium sulfur batteries composed of lithium metal anode and sulfur cathode have been recognized as one of such battery systems due to their extremely high theoretical energy density (2600 Wh kg −1 , almost 7 times higher than that of typical layered oxide cathodes) [9,10].…”