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N/P dual-doped three-dimensional porous carbon was synthesized via nano-CaCO 3 template-assistant carbonization of intumescent flame retardants (IFRs) precursor. [Display omitted] Heteroatom-doped three-dimensional (3D) porous carbons possess great potential as promising electrodes for high-performance supercapacitors. Inspired by the inherent features of intumescent flame retardants (IFRs) with universal availability, rich heteroatoms and easy thermal-carbonization to form porous carbons, herein we proposed a self-assembling and template self-activation strategy to produce N/P dual-doped 3D porous carbons by nano-CaCO 3 template-assistant carbonization of IFRs. The IFRs-derived carbon exhibited large specific surface area, well-balanced hierarchical porosity, high N/P contents and interconnected 3D skeleton. Benefitting from these predominant characteristics on structure and composition, the assembled supercapacitive electrodes exhibited outstanding electrochemical performances. In three-electrode 6 M KOH system, it delivered high specific capacitances of 407 F g−1 at 0.5 A g−1, and good rate capability of 61.2% capacitance retention at 20 A g−1. In two-electrode organic EMIMBF 4 /PC system, its displayed high energy density of 62.8 Wh kg−1 at a power density of 748.4 W kg−1, meanwhile it had excellent cycling stability with 84.7% capacitance retention after 10,000 cycles. To our best knowledge, it is the first example to synthesize porous carbon from IFRs precursor. Thus, the current work paved a novel and low-cost way for the production of high-valued carbon material, and expanded its application for high-performance energy storage devices. [ABSTRACT FROM AUTHOR]

In the backdrop of the carbon neutrality, lithium-ion batteries are being extensively employed in electric vehicles (EVs) and energy storage stations (ESSs). Extremely harsh conditions, such as vehicle to grid (V2G), peak-valley regulation and frequency regulation, seriously accelerate the life degradation. Consequently, developing long-life batteries for typical scenarios has emerged as a crucial focus for future endeavors. This paper concentrates on the fundamental scientific inquiries and comprehensively reviews aspects including the urgent requirements, degradation mechanisms, design methods, durability modeling and management approaches for long-life batteries. Firstly, it underscores the significance and urgency of developing long-life batteries under the typical EV and ESS scenarios. Subsequently, we delve into the long-life battery design methods concerning degradation mechanism suppression. Following this, the degradation modeling and advanced management strategies for achieving long-life batteries are elucidated. Lastly, facing the existing challenges and future opportunities, we provide new insights and perspectives to promote the development and practical application of long-life lithium-ion batteries. • A comprehensive review of the key issues towards long-life battery is presented. • The pressing long-life demands of EV and ESS typical application is highlighted. • A critical review of degradation mechanism and modeling is emphasized. • Challenges and solutions of long-life battery design and management are discussed. • Prospects of long-life battery are illustrated. [ABSTRACT FROM AUTHOR]

With the purpose to turn wastes into wealth and develop renewable energy, much effort has been focused on converting biowastes into porous carbons and exploring their application for supercapacitors. In this study, inspired by natural porous structure of biomass and small size of Sn nanoparticles, a one-step strategy was developed to convert waste wolfberry fruits into porous carbons by SnCl 2. The as-fabricated carbon exhibited large specific surface area of 1423 m2 g−1 and hierarchical porosity with total pore volume of 1.36 cm3 g−1. Meanwhile, the newly produced SnCl 2 with more than 95% recovery rate was reused as catalyst. Moreover, the porous carbon was applied for supercapacitive electrode. In three-electrode 6 M KOH system, it displayed outstanding capacitance of 365 F/g at 0.2 A g−1, good rate capability of 75% capacitance retention at 20 A g−1 and excellent cycling stability of 96.4% capacitance retention after 10000 cycles. In two-electrode 1 M Li 2 SO 4 system, its energy density reached 23.2 Wh kg−1 at a power density of 225 W kg−1. The current work provided a facile and low-cost method to recycle renewable biowastes into high-valued carbon material, and further expanded its application for high-performance energy storage devices. [Display omitted] [ABSTRACT FROM AUTHOR]

Summary High performance lithium batteries are in great demand for consumer electronics, electric vehicles and grid scale stationary energy storage. Transition metal sulfides based on conversion or alloying reactions have drawn much attention because of their significantly higher specific capacity than traditional insertion electrode materials. However, their poor cyclability caused by the large volume change during the lithium (Li) up-taking and extraction has hindered their further developments and applications in Li rechargeable batteries. This review outlines the fundamental mechanisms and obstacles of the transition metal sulfides associated with Li storage through conversion reaction and also discusses how the nanostructure design can successfully address their challenges. Recent progresses in the nanoparticle synthesis, nanostructure design, composite fabrication, and their effects on the electrochemical performances are summarized and discussed. In addition, remaining challenges and possibilities for further improvements are also prospected. [ABSTRACT FROM AUTHOR]

The derived lysine from biomass fermentation is a naturally abundant renewable resource. However, the small molecular size of lysine limits its processing and application. On the other side, carbonization of polylysine into high‐valued carbon materials is one of convenient options to apply for energy storage devices. Herein, we prepare polylysine@silica hybrid nanostructure through thermal polymerization of lysine and biosilicification of tetraethoxysilane (TEOS). Subsequently, nitrogen‐containing porous carbon flakes (NPCF) are synthesized upon carbonization. Interestingly, the synthesized NPCF presents hierarchical porous framework structure with interconnected micro‐meso‐macro pores. Consequently, the NPCF delivers an excellent supercapacitor performance. For instance, our characterizations display specific capacitance up to 242 F/g at 1 mV/s and 186 F/g at 1 A/g, and could keep 96.3% initial capacity after 10,000 cycles at 10 A/g. These achievements are because of hierarchical porosity, proper nitrogen content, and accessible surface area of nanostructured NPCF. Therefore, our work creates a novel and sustainable route for fabricating NPCF with promising applications in the supercapacitors. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 48214. [ABSTRACT FROM AUTHOR]

Designing porous and flexible electrodes with excellent electrochemical properties is crucial to fabricate high-performance flexible supercapacitors. Conductive polymer-based electrospun fibers are expected to be an ideal material for constructing flexible electrodes due to the enormous specific surface area, unique pore structure and inherent flexibility. However, the exploration of such electrospun fibers with facile preparation methods and high areal capacitance remains challenging. Herein, a novel polyetherimide@polyaniline core-shell fibrous membranes (PEI@PANI CFMs) is fabricated via simply coaxial electrospinning and 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS) secondary doping. With the aid of polyetherimide, highly concentrated emeraldine base polyaniline (EB-PANI) can be perfectly wrapped on the surface of fibers without any spinning assistants, ensuring the well-developed pore structures, superior hydrophilicity, good electrical conductivity and outstanding mechanical flexibility. Benefiting from the synergistic effect of structure and constituents, such flexible PEI@PANI CFMs as electrode materials can provide more accessible electrochemical active sites and decrease the ion diffusion resistance. Therefore, the PEI@PANI CFMs present outstanding areal capacitance of 1159.9 mF cm−2 and remarkable energy density of 46.91 μW h cm−2 in the electrodes and symmetric supercapacitors, demonstrating great potential for applications in flexible energy storage field. This fabrication strategy provides a simple and practicable way to manufacture polyaniline-based fibrous membranes for high-performance flexible electrode materials. [Display omitted] • PEI@PANI CFMs were firstly developed by coaxial electrospinning with high density PANI solution. • Continuous PANI shell without spinning assistants enabled high redox activity after AMPS doping. • PEI@PANI CFMs showed unique 3D network pore structure, superior hydrophilicity and flexibility. • PEI@PANI CFMs as electrode exhibited 1159.9 mF cm−2 area specific capacitance at 1 mA cm−2. • The symmetric device delivered remarkable energy density of 46.91 μW h cm−2 at 0.23 mW cm−2 [ABSTRACT FROM AUTHOR]