• Energy Research

A vehicle model is used to evaluate a novel powertrain that is comprised of a dual energy storage system (Dual ESS). The system includes two battery packs with different chemistries and the necessary electronic controls to facilitate their coordination and optimization. Here, a lithium-ion battery pack is used as the primary pack and a Zinc-air battery as the secondary or range-extending pack. Zinc-air batteries are usually considered unsuitable for use in vehicles due to their poor cycle life, but the model demonstrates the feasibility of this technology with an appropriate control strategy, with limited cycling of the range extender pack. The battery pack sizes and the battery control strategy are configured to optimize range, cost and longevity. In simulation the vehicle performance compares favourably to a similar vehicle with a single energy storage system (Single ESS) powertrain, travelling up to 75 km further under test conditions. The simulation demonstrates that the Zinc-air battery pack need only cycle 100 times to enjoy a ten-year lifespan. The Zinc-air battery model is based on leading Zinc-air battery research from literature, with some assumptions regarding achievable improvements. Having such a model clarifies the performance requirements of Zinc-air cells and improves the research community's ability to set performance targets for Zinc-air cells.

A bicontinuous-phase electrolyte with a well-balanced solvation sheath is proposed, which delivers fast desolvation kinetics and generates a uniform in situ solid electrolyte interface, thus achieving a long-lasting Zn anode at low temperatures.

A hybrid alkaline zinc–iodine redox flow battery has been designed with an unprecedented energy density record to date for an all-aqueous redox flow battery.

Electrochemical CO2 reduction (CO2RR) using renewable energy sources represents a sustainable means of producing carbon-neutral fuels. Unfortunately, low energy efficiency, poor product selectivity, and rapid deactivation are among the most intractable challenges of CO2RR electrocatalysts. Here, we strategically propose a "two ships in a bottle" design for ternary Zn-Ag-O catalysts, where ZnO and Ag phases are twinned to constitute an individual ultrafine nanoparticle impregnated inside nanopores of an ultrahigh-surface-area carbon matrix. Bimetallic electron configurations are modulated by constructing a Zn-Ag-O interface, where the electron density reconfiguration arising from electron delocalization enhances the stabilization of the *COOH intermediate favorable for CO production, while promoting CO selectivity and suppressing HCOOH generation by altering the rate-limiting step toward a high thermodynamic barrier for forming HCOO*. Moreover, the pore-constriction mechanism restricts the bimetallic particles to nanosized dimensions with abundant Zn-Ag-O heterointerfaces and exposed active sites, meanwhile prohibiting detachment and agglomeration of nanoparticles during CO2RR for enhanced stability. The designed catalysts realize 60.9% energy efficiency and 94.1 ± 4.0% Faradaic efficiency toward CO, together with a remarkable stability over 6 days. Beyond providing a high-performance CO2RR electrocatalyst, this work presents a promising catalyst-design strategy for efficient energy conversion.

Summary: Extreme fast charge (10 min to reach 80% state of charge) is one of the key limiting parameters preventing the widespread adoption of battery-based electric vehicles into the transportation sector. Many recent simulations and experimental-based studies have been recently published in this area with a specific focus on why extreme fast charge is challenging. These studies identified that cathode particle cracking and electrolyte transport limitation are the key barriers that have caused the well-known safety and stability problems. Interestingly, there have been very few studies that have demonstrated significant improvements toward a 10-min charge under high energy density conditions. Several strategies pertaining to electrolyte modifications (concentrated electrolyte and low viscosity additives) along with adaptive fast charging are highlighted and suggested.

AbstractThe design and synthesis of electrocatalysts possessing both hydrogen and oxygen evolution activity is of critical importance to simplify the water splitting system. In this work, we reported the preparation of porous Ni–Co nitride nanowires (NiCoN NWs) supported on carbon cloth, and used as bifunctional electrocatalysts to achieve overall water splitting. Benefiting from the 1D porous nanowire structure, the close contact between catalysts and support, and the increased conductivity, the resultant NiCoN NWs exhibited high activities in both the hydrogen and oxygen evolution reactions (HER and OER) with low overpotential at a current density of 10 mA cm−2 (≈145 mV for HER and 360 mV for OER), low Tafel slope (105.2 mV dec−1 for HER and 46.9 mV dec−1 for OER), and good electrochemical stability. Good stability was also obtained upon using the material as HER and OER catalysts in a two‐electrode system to split water.

An innovative design strategy for the structural and chemical synergistic encapsulation of polysulfides is proposed enabling the achievement of ultra stable lithium–sulfur batteries.

AbstractVanadium oxide cathode materials with stable crystal structure and fast Zn2+ storage capabilities are extremely important to achieving outstanding electrochemical performance in aqueous zinc‐ion batteries. In this work, a one‐step hydrothermal method was used to manipulate the bimetallic ion intercalation into the interlayer of vanadium oxide. The pre‐intercalated Cu ions act as pillars to pin the vanadium oxide (V‐O) layers, establishing stabilized two‐dimensional channels for fast Zn2+ diffusion. The occupation of Mn ions between V‐O interlayer further expands the layer spacing and increases the concentration of oxygen defects (Od), which boosts the Zn2+ diffusion kinetics. As a result, as‐prepared Cu0.17Mn0.03V2O5−□·2.16H2O cathode shows outstanding Zn‐storage capabilities under room‐ and low‐temperature environments (e.g., 440.3 mAh g−1 at room temperature and 294.3 mAh g−1 at −60°C). Importantly, it shows a long cycling life and high capacity retention of 93.4% over 2500 cycles at 2 A g−1 at −60°C. Furthermore, the reversible intercalation chemistry mechanisms during discharging/charging processes were revealed via operando X‐ray powder diffraction and ex situ Raman characterizations. The strategy of a couple of 3d transition metal doping provides a solution for the development of superior room‐/low‐temperature vanadium‐based cathode materials.