3D bioprinting is a group of rapidly growing techniques that allows building engineered tissue constructs with complex and hierarchical structures, mechanical and biological heterogeneity. It enables ...implementation of various bioinks through different printing mechanisms and precise deposition of cell and/or biomolecule laden biomaterials in predefined locations. This review briefly summarizes applicable bioink materials and various bioprinting techniques, and presents the recent advances in bioprinting of cardiovascular tissues, with focusing on vascularized constructs, myocardium and heart valve conduits. Current challenges and further perspectives are also discussed to help guide the bioink and bioprinter development, improve bioprinting strategies and direct future organ bioprinting and translational applications.
The newly emerged aqueous Zn–organic batteries are attracting extensive attention as a promising candidate for energy storage. However, most of them suffer from the unstable and/or soluble nature of ...organic molecules, showing limited cycle life (≤3000 cycles) that is far away from the requirement (10 000 cycles) for grid‐scale energy storage. Here, a new aqueous zinc battery is proposed by using sulfur heterocyclic quinone dibenzob,ithianthrene‐5,7,12,14‐tetraone (DTT) as the cathode. The cell shows a high reversible capacity of 210.9 mAh gDTT−1 at 50 mA gDTT−1 with a high mass loading of 5 mgDTT cm−2, along with a fast kinetics for charge storage. Electrochemical measurements, ex situ analyses, and density functional theory calculation successfully demonstrate that the DTT electrode can simultaneously store both protons (H+) and Zn2+ to form DTT2(H+)4(Zn2+), where Zn2+ is bound to the carboxyl groups from the adjacent DTT molecules with improved stability. Benefitting from the improved molecular stability and the inherent low solubility of DTT and related discharge products, the DTT//Zn full cell exhibits a superlong life of 23 000 cycles with a capacity retention of 83.8%, which is much superior to previous reports.
An aqueous zinc battery is proposed by using sulfur heterocyclic quinone dibenzob,ithianthrene‐5,7,12,14‐tetraone (DTT) as the cathode, showing high capacity and fast kinetics. Benefitting from the improved molecular stability and the inherent low solubility of DTT, the battery exhibits a superlong life of 23 000 cycles, which is much superior to previous reports.
Due to the adjacent cell-to-cell equalization, the classical switched-capacitor equalizer (SCE) has seriously low balancing speed and efficiency for a long battery string. Therefore, a series of ...star-structured switched-capacitor equalizers are proposed to achieve high balancing speed and efficiency independent of the cell number and the cell voltage distribution without significant influences on the size, cost, control, and reliability compared with the classical SCE. The proposed topologies use the least mosfets and capacitors to achieve the most direct balancing paths between any two cells, being the optimal switched-capacitor structures. An analysis method for the slow switching limit and the fast switching limit impedances of the proposed equalizers is proposed to provide a theoretical guidance for the selection of the switching frequency. The inherent advantages of the proposed systems are the small size, low cost, simple control, high efficiency, fast speed, easy modularization, and high reliability. A prototype for four lithium-ion battery cells is set up. Experimental results show improved balancing performances with strong robustness. Moreover, the measured peak balancing efficiency is about 93.1% despite faster balancing speed.
Lithium metal is an ideal anode for high‐energy rechargeable batteries at low temperature, yet hindered by the electrochemical instability with the electrolyte. Concentrated electrolytes can improve ...the oxidative/reductive stability, but encounter high viscosity. Herein, a co‐solvent formulation was designed to resolve the dilemma. By adding electrochemically “inert” dichloromethane (DCM) as a diluent in concentrated ethyl acetate (EA)‐based electrolyte, the co‐solvent electrolyte demonstrated a high ionic conductivity (0.6 mS cm−1), low viscosity (0.35 Pa s), and wide range of potential window (0–4.85 V) at −70 °C. Spectral characterizations and simulations show these unique properties are associated with the co‐solvation structure, in which high‐concentration clusters of salt in the EA solvent were surrounded by mobile DCM diluent. Overall, this novel electrolyte enabled rechargeable metallic Li battery with high energy (178 Wh kg−1) and power (2877 W kg−1) at −70 °C.
Batteries in a cold climate: A cosolvent electrolyte with a unique cosolvation structure, has a wide stable electrochemical window (0–4.85 V), sufficient ionic conductivity (0.6 mS cm−1), and low viscosity (0.35 Pa s) at −70 °C, which facilitated preparation of a rechargeable metallic lithium battery for use in extreme temperatures with a high energy density of 178 Wh kg−1 at −70 °C.
Aqueous rechargeable zinc batteries (ARZBs) are recently prevailing devices that utilize the abundant Zn resources and the merits of aqueous electrolytes to become a competitive alternative for ...large‐scale energy storage. Benefiting from the unique inductive effect and flexible structure, the past five years have experienced a diversiform of phosphate‐based polyanion materials that are used as cathodes in ARZBs. In this review, the most recent advances in the Zn2+ storage mechanisms and electrolyte optimization of the phosphate‐based cathodes of ARZBs, which mainly focus on vanadium/iron‐based phosphates and their derivatives are presented. Furthermore, in addition to significant progress on polyanion phosphate‐based cathode materials, the design strategies both for electrode materials and compatible electrolytes are also elaborated to improve the energy density and extend the cycling life of aqueous Zn/polyanion batteries.
In this review, the latest advances in phosphates‐based polyanionic cathodes for Zn2+ storage mechanism and electrochemical performance are summarized. In addition, the challenges are pointed out for the phosphates‐based polyanionic cathodes in aqueous rechargeable zinc batteries and provide alternative strategies for designing high‐performance Zn/Polyanion batteries.
Batteries with a Li‐metal anode have recently attracted extensive attention from the battery communities owing to their high energy density. However, severe dendrite growth hinders their practical ...applications. More seriously, when Li dendrites pierce the separators and trigger short circuit in a highly flammable organic electrolyte, the results would be catastrophic. Although the issues of growth of Li dendrites have been almost addressed by various methods, the highly flammable nature of conventional organic liquid electrolytes is still a lingering fear facing high‐energy‐density Li‐metal batteries given the possibility of thermal runaway of the high‐voltage cathode. Recently, various kinds of nonflammable liquid‐ or solid‐state electrolytes have shown great potential toward safer Li‐metal batteries with minimal detrimental effect on the battery performance or even enhanced electrochemical performance. In this review, recent advances in developing nonflammable electrolyte for high‐energy‐density Li‐metal batteries including high‐concentration electrolyte, localized high‐concentration electrolyte, fluorinated electrolyte, ionic liquid electrolyte, and polymer electrolyte are summarized. Then, the solvation structure of different kinds of nonflammable liquid and polymer electrolytes are analyzed to provide insight into the mechanism for dendrite suppression and fire extinguishing. Finally, guidelines for future design of nonflammable electrolyte for safer Li‐metal batteries are provided.
Nonflammable organic electrolytes are very promising to address the safety issue facing Li‐metal batteries. Several types of nonflammable organic electrolytes are reviewed from the perspective of solvation structure. The analysis of solvation structure provides insight into the nonflammability and the mechanism for Li‐dendrite suppression. Finally, future guidelines for designing nonflammable electrolyte are provided.
Sodium (Na) is one of the more abundant elements on earth and exhibits similar chemical properties as lithium (Li), indicating that Na could be applied to a similar battery system. Like aqueous ...Li‐ion batteries, aqueous sodium‐ion batteries (ASIBs) are also demonstrated to be one of the most promising stationary power sources for sustainable energies such as wind and solar power. Compared to traditional nonaqueous batteries, ASIBs may solve the safety problems associated with the highly toxic and flammable organic electrolyte in the traditional lithium‐ion and sodium‐ion batteries. During the past decades, many efforts are made to improve the performance of the ASIBs. The present review focuses on the latest advances in the exploration and development of ASIB systems and related components, including cathodes, anodes, and electrolytes. Previously reported studies are briefly summarized, together with the presentation of new findings based on the electrochemical performance, cycling stability, and morphology approaches. In addition, the main opportunities, achievements, and challenges in this field are briefly commented and discussed.
Compared to nonaqueous batteries, Aqueous sodium‐ion batteries (ASIB) solve the safety problem associated with the highly toxic and flammable organic electrolyte. This review focuses on the latest advances in the development of ASIB systems, including cathode, anode, and electrolyte. Here, the recent progress, challenges, and prospects are proposed to guide the further development of ASIB.
Layered materials have received extensive attention for widespread applications such as energy storage and conversion, catalysis, and ion transport owing to their fast ion diffusion, exfoliative ...feature, superior mechanical flexibility, tunable bandgap structure, etc. The presence of large interlayer space between each layer enhances intercalation of the guest ion or molecule, which is beneficial for fast ion diffusion and charge transport along the channels. This intercalation reaction of layered compounds with guest species results in material with improved mechanical and electronic properties for efficient energy storage and conversion, catalysis, ion transport, and other applications. This review extensively discusses the intercalation of guest ionic or molecular species into layered materials used for various types of applications. It assesses the intercalation strategies, mechanism of ionic or molecular intercalation reactions, and highlights recent advancements. The electrochemical performances of several typical intercalated materials in batteries, supercapacitors, and electrocatalytic systems have been thoroughly discussed. Moreover, the challenges in the design and intercalation of layered materials, as well as prospects of future development are highlighted.
This review systematically discusses the intercalation mechanism and method of guest species into layered materials, highlights their recent application such as lithium ion batteries, sodium ion batteries, aqueous zinc batteries, supercapacitors, hydrogen evolution reaction and oxygen evolution reaction, and emphasizes the strategies to enhance their properties and fundamental issues of the intercalated layered materials.
Given the low cost, ease of fabrication, high safety, and environmental‐friendly characteristics, aqueous rechargeable batteries using mild aqueous solutions as electrolytes (pH is close to 7) and a ...monovalent/multivalent metal ion as charge carrier, are attracting extensive attention for energy storage. However, accompanied by advantages of mild aqueous electrolyte mentioned above, there are some challenges that stand in the way of the development of these aqueous rechargeable batteries, such as the narrow stable electrochemical window of water, instability of electrode materials, undesired side reactions, etc. In recent years, a massive effort is devoted to overcoming the drawbacks, and some encouraging works have arisen. In this review, the latest advances of electrolyte and electrode materials in aqueous batteries based on monovalent ion (Li+, Na+, K+) and multivalent ion (Zn2+, Mg2+, Ca2+, Al3+) are briefly reviewed.
Rechargeable batteries using mild aqueous electrolytes (pH is close to 7) provide a promising solution for the large‐scale energy storage and wearable/biocompatible applications due to the high safety and low cost. Three development tendencies of these batteries are summarized: charge carriers from monovalent ions to multivalent ions; electrolyte composition from “salt‐in‐water” to “water‐in‐salt”; electrodes from inorganic materials to organic materials.
PDF
