Electrolytes have played critical roles in electrochemical energy storage. In Li-ion battery, liquid electrolytes have shown their excellent performances over decades, such as high ionic conductivity (∼10–3 S cm–1) and good contacts with electrodes. However, the use of liquid electrolytes often brought risks associated with leakage and combustion of organic electrolytes. Hence, polymer electrolytes become potential candidates to replace liquid electrolyte systems. Although solid polymer electrolytes (SPEs) offer better safety and good mechanical properties to take over liquid electrolytes, most of them only deliver low ionic conductivities (∼10–8 S cm–1) and poor contact with electrodes, resulting in poor cycle performance and low electrical capacity of the batteries. In addition, gel polymer electrolytes (GPEs) have received increasing research attention due to their relevant characteristics, which extend from liquid electrolytes and solid polymer electrolytes. In this review, state-of-the-art samples of gel polymer electrolytes are elucidated with respect to their structural design and electrochemical properties to determine their application potential in Li-ion batteries (LIBs). First, we present the general requirements of GPEs for LIBs applications, followed by important electrochemical properties of GPEs for LIBs including ionic conductivity, transference number, and ionic transport mechanisms. Furthermore, recent progress of common polymers, namely, polyether, polyvinyl, polynitrile, polycarbonate, and polyacrylate, as polymer host of GPEs has been carefully explained. Finally, the alternative polymers were also discussed to provide new approaches for further developments of GPEs to fulfill the demanded properties for practical applications.

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Aromatic polyimide (PI) derivatives have recently been investigated as redox-active electrode materials for Li-ion batteries because of their high thermal stability and thermo-oxidative stability complemented by excellent solvent resistance, good electrical and mechanical properties, and chemical resistance. In this work, we report two PI derivatives from a newly synthesized 4,4′-diamino-3″,4″-dicyanotriphenylamine (DiCN-TPA) monomer and two dianhydrides, pyromellitic dianhydride (PMDA) and 1,4,5,8-naphthalenetetracarboxylic dianhydride (NTCDA); designated as TPA-PMPI and TPA-NTCPI, respectively, as electrode materials for Li-ion batteries. Characterizations of the PIs reveal excellent thermal stability and bipolar property. The incorporation of DiCN-TPA into the polymer structure resulted to a disordered chain arrangement, thus giving high glass transition temperatures (T g). Electrochemical performance tests reveal that TPA-NTCPI cathode delivered a reversible specific capacity of 150 mAh g–1 at 0.1 A g–1 and exhibited a stability up to 1000 cycles. On the other hand, TPA-PMPI anode delivered a high specific capacity of up to 1600 mAh g–1 at 0.1 A g–1 after 100 cycles. The electrochemical performance of TPA-NTCPI cathode and TPA-PMPI anode are both among the best compared with other reported aromatic PI-based electrodes. The long cycle lifetime and excellent battery performance further suggest that TPA-NTCPI and TPA-PMPI are promising organic electrode materials for next generation Li-ion batteries.

Multifunctional energy storage devices show great promise in reducing the size and volume of devices, improving the storage capacity, and minimizing the cost in materials and fabrication while bringing the...

Metal−organic frameworks (MOFs) are porous crystalline materials with tailorable structural versatility that were recently considered as one of the most promising alternative anode materials for lithium-ion batteries. Herein, we have synthesized lead-based MOFs (Pb-1,3,5-benzenetricarboxylate, Pb-BTC), which had a high efficiency and reversibe lithium storage for anode material in lithium-ion batteries. The Pb-BTC based battery delivers highly reversible lithium storage capacities of 625 and 450 mA h g −1 at current densities of 0.1 and 0.5 A g −1 , respectively, and can maintain its performance up to 150 charging/discharging cycles. The ex situ X-ray photoelectron spectroscopic studies on the electrode materials at different charging/ discharging states and cyclic intervals reveal that the Li + insertion, conversion, and alloying mechanism play central roles on improving the lithium storage capability. The DFT simulation reveals that the Pb sites in MOFs absorb Li atoms efficiently that support the high storage capacity. The electrochemical performance of Pb-BTC in our work is among the best compared with other reported MOF anode electrodes.

Metal–organic frameworks (MOFs) have received intensive scientific attention as electrode materials for lithium‐ion batteries because of their tailorable physical and chemical properties by incorporating different organic ligands. Herein, a zinc‐based MOF (Zn‐MOF) with a special dual‐ligand system, tris(4‐(1H‐1,2,4‐triazol‐1‐yl)phenyl)amine and dihydroxylterepthate, as anode material for lithium‐ion batteries is successfully fabricated. The activated Zn‐MOF based battery delivered a reversible and efficient lithium storage capacity of ≈200 mA h g−1 at 0.5 A g−1 with a 99% Coulombic efficiency over 1000 cycles. The sweep rate cyclic voltammetry and ex situ Fourier transform infrared spectroscopy on the electrode materials at different charging/discharging states reveal that lithium insertion in the organic moiety with a diffusion‐controlled process plays a critical role in the storage mechanism of the Zn‐MOF anode. Further spectroscopic analysis reveals the excellent material stability of dual‐ligand Zn‐MOFs with limited solid–electrolyte interface growth under long‐term charge–discharge operation, which is beneficial for next‐generation battery anodes.

This study investigates the permeance and rejection efficiencies of different dyes (Rhodamine B and methyl orange), folic acid and a protein (bovine serum albumin) using graphene oxide composite membrane. The ultrathin separation layer of graphene oxide (thickness of 380 nm) was successfully deposited onto porous polyvinylidene fluoride-polyacrylic acid intermediate layer on nonwoven support layer using vacuum filtration. The graphene oxide addition in the composite membrane caused an increased hydrophilicity and negative surface charge than those of the membrane without graphene oxide. In the filtration process using a graphene oxide composite membrane, the permeance values of pure water, dyes, folic acid and bovine serum albumin molecules were more severely decreased (by two orders of magnitude) than those of the nonwoven/polyvinylidene fluoride-polyacrylic acid composite membrane. However, the rejection efficiency of the graphene oxide composite was significantly improved in cationic Rhodamine B (from 9% to 80.3%) and anionic methyl orange (from 28.3% to 86.6%) feed solutions. The folic acid and bovine serum albumin were nearly completely rejected from solutions using either nonwoven/polyvinylidene fluoride-polyacrylic acid or nonwoven/polyvinylidene fluoride-polyacrylic acid/graphene oxide composite membrane, but the latter possessed anti-fouling property against the protein molecules. The separation mechanism in nonwoven/polyvinylidene fluoride-polyacrylic acid membrane includes the Donnan exclusion effect (for smaller-than-pore-size solutes) and sieving mechanism (for larger solutes). The sieving mechanism governs the filtration behavior in the nonwoven/polyvinylidene fluoride-polyacrylic acid/graphene oxide composite membrane.

Aromatic polyamides, aramids, have recently drawn reasech attentions for energy storage applications due to their outstanding physical and chemical properties. In this work, we report three new aramids containing dicyanotriphenylamine...