Mechanistically Novel Frontal-Inspired In Situ Photopolymerization:An Efficient Electrode|Electrolyte Interface Engineering Method for High Energy Lithium Metal Polymer Batteries

The solvent-free in situ polymerization technique has the potential to tailor-make conformal interfaces that are essential for developing durable and safe lithium metal polymer batteries(LMPBs).Hence,much attention has been given to the eco-friendly and rapid ultraviolet(UV)-induced in situ photopolymerization process to prepare solid-state polymer electrolytes.In this respect,an innovative method is proposed here to overcome the challenges of UV-induced photopolymerization(UV-curing)in the zones where UV-light cannot penetrate,especially in LMPBs where thick electrodes are used.The proposed frontal-inspired photopolymerization(FIPP)process is a diverged frontal-based technique that uses two classes(dual)of initiators to improve the slow reaction kinetics of allyl-based monomers/oligomers by at least 50%compared with the conventional UV-curing process.The possible reaction mechanism occurring in FIPP is demonstrated using density functional theory calculations and spectroscopic investigations.Indeed,the initiation mechanism identified for the FIPP relies on a photochemical pathway rather than an exothermic propagating front forms during the UV-irradiation step as the case with the classical frontal photopolymerization technique.Besides,the FIPP-based in situ cell fabrication using dual initiators is advantageous over both the sandwich cell assembly and conventional in situ photopolymerization in overcoming the limitations of mass transport and active material utilization in high energy and high power LMPBs that use thick electrodes.Furthermore,the LMPB cells fabricated using the in situ-FIPP process with high mass loading LiFePO_(4)electrodes(5.2 mg cm^(-2))demonstrate higher rate capability,and a 50%increase in specific capacity against a sandwich cell encouraging the use of this innovative process in large-scale solid-state battery production.

Organic/inorganic nanocomposite polymer electrolyte

The organic/inorganic nanocomposites polymer electrolytes were designed and synthesized. The organic/inorganic nanocomposites membrane materials and their lithium salt complexes have been found thermally stable below 200 °C. The conductivity of the organic/inorganic nanocomposites polymer electrolytes prepared at room temperature was at magnitude range of 10(?6) S/cm.

PREPARATION AND ELECTROCHEMICAL CHARACTERISTICS OF POLYMER ELECTROLYTE MEMBRANES BASED ON SAN/PVDF-HFP BLENDS

A copolymer of poly（acrylonitrile-co-styrene） （SAN） was synthesized via an emulsion polymerization method. Novel polymer electrolyte membranes cast from the blends of poly（vinylidene fluoride-co-hexafluoropropylene） （PVDF- HFP）, SAN and fumed silica （SIO2） are microporous and can be used in polymer lithium-ion batteries. The membrane shows excellent characteristics such as high ionic conductivity and good mechanical strength when the mass ratio between SAN and PVDF-HFP and SiO2 is 3.5/31.5/5. The ionic conductivity of the membrane soaked in a liquid electrolyte of 1 mol/L LiPF6/EC/DMC/DEC is 4.9 × 10^-3 S cm^-1 at 25℃. The membrane is electrochemical stable up to 5.5 V versus Li^＋/Li in the liquid electrolyte. The influences of SiO2 content on the porosity and mechanical strength of the membranes were studied. Polymer lithium-ion batteries based on the membranes were assembled and their performances were also studied.

Autosub6000:A Deep Diving Long Range AUV

With an ultimate range up to 1000 km,a maximum operating depth of 6000 m,and a generous payload capacity,Autosub6000 is well placed to become one of the world's most capable deep diving Autonomous Underwater Vehicles(AUVs). Recently,Autosub6000 successfully completed its first deep water engineering trials,and in September 2008,fitted with a multibeam sonar,will carry out its first science missions.This paper will describe how we are tackling the design issues that specifically affect a deep diving AUV which must be capable of operating with true autonomy,independently of the mother ship, namely:carrying adequate energy for long endurance and range,coping with varying buoyancy,and maintaining accurate navigation throughout missions lasting up to several days.Results from the recent engineering trails are presented,and future missions and development plans are discussed.

Electrochemical performance of all-solid lithium ion batteries with a polyaniline film cathode

We have prepared a high-density polyaniline（PANI） paste（50 mg/m L）, with similar physical properties to those of paints or pigments. The synthesis of PANI is confirmed by Fourier transform infrared（FT-IR） spectroscopy. The morphologies of PANI, doped PANI, and doped PANI paste are confirmed by scanning electron microscopy（SEM）. Particles of doped PANI paste are approximately 40–50 nm in diameter, with a uniform and cubic shape. The electrochemical performances of doped PANI paste using both liquid and solid polymer electrolytes have been measured by galvanostatic charge and discharge process. The cell fabricated with doped PANI paste and the solid polymer electrolyte exhibits a discharge capacity of ～87 μAh/cm2（64.0 m Ah/g） at the second cycle and～67 μAh/cm2（50.1 m Ah/g） at the 100 th cycle.

The interphasial degradation of 4.2 V-class poly(ethylene oxide)-based solid batteries beyond electrochemical voltage limit

Solid-state polymer electrolytes(SPEs)have attracted increasing attention due to good interfacial contact,light weight,and easy manufacturing.However,the practical application of SPEs such as the most widely studied poly(ethylene oxide)(PEO)in high-energy solid polymer batteries is still challenging,and the reasons are yet elusive.Here,it is found that the mismatch between PEO and 4.2 V-class cathodes is beyond the limited electrochemical window of PEO in the solid Li Ni_(1/3)Mn_(1/3)Co_(1/3)O_(2)(NMC)-PEO batteries.The initial oxidation of PEO initiates remarkable surface reconstruction of NMC grains in solid batteries that are different from the situation in liquid electrolytes.Well-aligned nanovoids are observed in NMC grains during the diffusion of surface reconstruction layers towards the bulk in solid batteries.The substantial interphasial degradation,therefore,blocks smooth Li+transport across the NMC-PEO interface and causes performance degradation.A thin yet effective Li F-containing protection layer on NMC can effectively stabilize the NMC-PEO interface with a greatly improved lifespan of NMC|PEO|Li batteries.This work deepens the understanding of degradations in high-voltage solid-state polymer batteries.

Ningde Becomes The World's Largest Polymer Lithium-ion Battery Production Base

On November 13,the reporter learned from relevant municipal departments that after 9years of development,Ningde City has become the world’s largest polymer lithium-ion battery production base with its products supplied to well-known brands such as Apple,Huawei,Xiaomi,OPPO and Meizu.Since the establishment of Amperex Technology Limited(ATL)in March 2008,Ningde has seen an explosive growth in

SYNTHESIS, CHARACTERIZATION AND ION TRANSPORT PROPERTIES OF HOT-PRESSED SOLID POLYMER ELECTROLYTES (1-x) PEO:x KI

Synthesis and ion transport properties of hot-pressed solid polymer electrolytes （SPEs）, （l-x） PEO： x KI, where x is the content of KI in wt%, are reported. A hot-press technique has been used for the formation of the polymeric membranes in place of the usual solution cast method. The composition （80 PEO：20 KI） was identified as the highest conducting polymer electrolyte on the basis of compositional dependent conductivity studies of PEO：KI films. A conductivity enhancement of more than two orders of magnitude from that of the pure PEO was achieved. Materials characterization and ion transport mechanism were explained by using various experimental techniques.

Electrolyte and anode-electrolyte interphase in solid-state lithium metal polymer batteries:A perspective

The interest for solid-state lithium metal(Li◦)batteries(SSLMBs)has been growing exponentially in recent years in view of their higher energy density and eliminated safety concerns.Solid polymer electrolytes(SPEs)are soft ionic conductors which can be easily processed into thin films at industrial level;these unique features confer solid-state Li◦polymer batteries(SSLMPBs,i.e.,SSLMBs utilizing SPEs as electrolytes)distinct advantages compared to SSLMBs containing other electrolytes.In this article,we briefly review recent progresses and achievements in SSLMPBs including the improvement of ionic conductivity of SPEs and their interfacial stability with Li◦anode.Moreover,we outline several advanced in-situ and ex-situ characterizing techniques which could assist in-depth understanding of the anode-electrolyte interphases in SSLMPBs.This article is hoped not only to update the state-of-the-art in the research on SSLMPBs but also to bring intriguing insights that could improve the fundamental properties(e.g.,transport,dendrite formation,and growth,etc.)and electrochemical performance of SSLMPBs.

Carbonyl polymeric electrode materials for metal-ion batteries

Benefiting from the diversity and subjective design feasibility of molecular structure, flexibility,lightweight, molecular level controllability, resource renewability and relatively low cost, polymeric electrode materials are promising candidates for the next generation of sustainable energy resources and have attracted extensive attention for the foreseeable large scale applications. The conductive polymers have been utilized as electrode materials in the pioneer reports, which, however, have the disadvantages of low stability, low reversibility and slope voltage due to the delocalization of charges in the whole conjugated systems. The discovery of carbonyl materials aroused the interest of organic and polymeric materials for batteries again. This review presents the recent progress in carbonyl polymeric electrode materials for lithium-ion batteries, sodium-ion batteries and magnesium-ion batteries. This comprehensive review is expected to be helpful forarousing more interest of organic materials for met

Polyacrylonitrile-based gel polymer electrolyte filled with Prussian blue forhigh-performance lithium polymer batteries

Lithium polymer batteries(LPBs) rely on a high ion transport to gain improved cell performance.Thermostable and porous gel polymer electrolytes(GPEs) have attracted much attention due to their excellent properties in electrolyte wettability and ionic conductivity.In this work,iron-nickel-cobalt trimetal Prussian blue analogue(PBA) nanocubes are filled into the electro spun polyacrylonitrile(PAN)-based membranes to generate GPE composites with morphological superiority consisting of fine fibers and interconnected pores.The thus obtained PBA@PAN fibrous membrane showcases good thermal stability,high porosity and electrolyte uptake,as well as a peak io nic conductivity of 2.7 mS/cm with the addition of 10% PBA,Consequently,the assembled lithium iron phosphate(LiFePO_(4)) battery using PBA@PAN-10 as the GPE delivers a high capacity of 152.2 mAh/g at 0.2 C and an ultralow capacity decay of0.09% per cycle in a long-te rm cycle life of 350 cycles at 1 C,endorsing its promising applications in LPBs.

Pressure-induced polymerization of butyndioic acid and its Li^＋ salt

Conductive organic polymers with carbonyl groups are considered as potential cathode materials of the Li^＋ battery. Driven by extremely high pressure, 2-butyndioic acid and its Li~＋ salt polymerize at around 4 and 10 GPa, respectively, which demonstrates that pressure-induced polymerization is a robust method for synthesizing substituted polyacetylene-like conductors.