The open circuit voltage of lithium ion batteries in equilibrium state, as a vital thermodynamic characteristic parameter, is extensively studied for battery state estimation and management. However, ...the time-consuming relaxation process, usually for several hours or more, seriously hinders the widespread application of open circuit voltage. In this paper, a novel voltage relaxation model is proposed to predict the final open circuit voltage when the lithium ion batteries are in equilibrium state with a small amount of sample data in the first few minutes, based on the concentration polarization theory. The Nernst equation is introduced to describe the evolution of relaxation voltage. The accuracy and effectiveness of the model are verified using experimental data on lithium ion batteries with different kinds of electrodes (LiCoO2/mesocarbon-microbead and LiFePO4/graphite) under different working conditions. The validation results show that the presented model can fit the experimental results very well and the predicted values are quite accurate by taking only 5 min or less. The satisfying results suggest that the introduction of concentration polarization theory might provide researchers an alternative model form to establish voltage relaxation models.
Lithium carbon fluorides (Li/CFx) primary batteries are of highly interests due to their high specific energy and power densities. The shelf life is one of the major concerns when they are used as ...backup power, emergency power and storage power in landers, manned spacecraft or military applications. In this work, real-time storage tests are carried out for both energy-type and power-type Li/CFx pouch batteries at 25 °C. Accelerated storage tests are performed at elevated temperature of 55 °C. The electrochemical tests are conducted throughout the aging period of 0–365 days for various batteries to study the effects of temperature on both type of batteries. The observed electrochemical behaviors are explained with the evidences from multiple characterizations for post-tested samples.
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•CFx materials determine the electrochemical performance.•Storage at 55 °C affects the delivered specific capacity and discharge voltage.•The formation of LiF results in the capacity fading.•The increasing film impedance leads to the drop of discharge voltage.
Lithium secondary batteries have attracted considerable attention due to their great potential to achieve ultrahigh energy density for future use. However, the Li metal anode suffers dendrite ...formation during repeated stripping/plating, hindering its practical realization. Herein, for the first time, an artificial solid electrolyte interphase layer, lithium phosphorus oxynitride (LiPON), is introduced for the lithium anode, and the viable application in high-energy lithium secondary pouch cell is probed. LiPON is stable with lithium and in the air, which can protect the lithium from the side reaction with H2O and O2 effectively. In low-energy batteries, the LiPON layer can enhance the efficiency of lithium deposition/dissolution and prolong the lifespan of the batteries. Further on, the discharge capacities of the lithium secondary cells with an energy density over 350 Wh kg–1 deploying LiPON-coated Li anodes drop fast, and the batteries are prone to severe polarization leading to the termination of life. Nonuniform current density resulting from the cracks caused by the large mass of lithium stripping/plating is ascribed to being the decisive factor shortening the life of batteries. Generally speaking, more and further exploration should be focused on the modification of the large-area lithium anode to accomplish high-energy-density lithium batteries for practical applications.
The pore structure and electrochemical performances of mesoporous carbons prepared by silica sol template method as electrode material for supercapacitor were investigated in this work. The pore size ...distribution of the mesoporous carbons changes from unimodal to bimodal and the mean pore size increases with the increase of silica sol/glucose ratio. The specific capacitance of the mesoporous carbons also increases with the increase of silica sol/glucose ratio. A novel technique named as template–chemical activation method, combining both template and chemical activation methods, is proposed, which can effectively control the pore structure, improving the electrochemical properties of the mesoporous carbon with improved porosity especially microporosity.
The practical application of Pyrite iron disulfide (FeS2) as anode material of sodium-ion battery is limited by its low electronic conductivity, large volume changes during charge/discharge. To ...overcome these challenges, a novel structure design single-walled carbon nanotubes (SWCNTs) composited polyaniline (PANI)-wrapped FeS2 (FeS2-PANI-SWCNTs) electrodes are successfully achieved in this work. PANI can protect the FeS2 particles from collapse and offer a protective layer to relive the polysulfides shuttling effect, and also promote the electron and Na+ diffusion during the chemical conversion process. Under the dual protection of PANI and SWCNTs, the FeS2-PANI-SWCNTs film electrode demonstrates a good structural integrity, which accounts for the excellent rate capability and long cycling performance. In addition, the PANI coating and SWCNT network in the fabricated electrode can synergistically anchor polysulfides and therefore strongly suppress shuttle effect during the charge–discharge processes, resulting in less capacity loss. The anode with a loading 3.2 mg cm−2 of FeS2 coated with PANI exhibits the initial coulombic efficiency of 81.5% and delivers a specific capacity of 625.8 mAh g−1 after 100 cycles at 200 mA g−1. High flexible and binder-free FeS2-PANI-SWCNTs film anode demonstrates a reversible capacity of 537 mAh g−1 after 550 cycles at 1 A g−1. This research may offer an efficient method to improve electrochemical performance of the metal sulfides in sodium-ion batteries.
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•Natural Pyrite FeS2 micro particles was explored as anode material for sodium-ion batteries.•SWCNTs composited PANI-wrapped FeS2 flexible electrode was successfully achieved.•PANI coating and SWCNT network buffer volumetric changes of FeS2.•This study offers a simple and efficient route for high performance SIBs.
The metastable phase of well-faceted, hexagonal, prism-like molybdenum oxide hydrate (MoO
3
·0.55H
2
O) was successfully synthesized by evaporating molybdic acid solution prepared through cation ...membrane electrolysis of Na
2
MoO
4
·2H
2
O aqueous solution. The obtained crystals were characterized by X-ray diffraction (XRD), thermogravimetric (TG), scanning electronic microscopy (SEM) and photoluminescence (PL) spectrophotometry. The as-prepared MoO
3
·0.55H
2
O rods were of 2-4 μm in width and 5-12 μm in length. The MoO
3
·0.55H
2
O microrods displayed photoluminescence properties at room temperature and were transformed into stable orthorhombic α-MoO
3
after air annealing at 380 °C. Moreover, the influence of temperature factor on the phase transformation process, morphology and photoluminescence properties of MoO
3
·0.55H
2
O was investigated in detail.
Using 2-methoxyethanol-water solution as the media, nano-LiFePO4/carbon composite cathodes material have been synthesized via a simple and new sol-gel route from iron nitrate, lithium dihydrogen ...phosphate. X-ray diffraction analysis, field emission scanning electron microscopy and transmission electron microscope observations showed that LiFePO4 with a well-crystallized olivine structure appeared in the heat-treated powder and the average particle size was about 65 nm with uniform distribution. In the process of heat treatment, the sucrose decomposed on the surface of LiFePO4 particles to in situ form carbon conductive webs structure. The favorable physical characteristics of the nano-LiFePO4/carbon composite materials exhibited excellent rate performance and cyclability, delivering a discharge capacity of 103 mAh g-1 (10C charge/discharge rate) after 50 cycles.
Mammalian orthoreovirus (MRV) outer capsid protein σ3 is a multifunctional protein containing a double-stranded RNA-binding domain, which facilitates viral entry and assembly. We reasoned that σ3 has ...an innate immune evasion function. Here, we show that σ3 protein localizes in the mitochondria and interacts with mitochondrial antiviral signaling protein (MAVS) to activate the intrinsic mitochondria-mediated apoptotic pathway. Consequently, σ3 protein promotes the degradation of MAVS through the intrinsic caspase-9/caspase-3 apoptotic pathway. Moreover, σ3 protein can also inhibit the expression of the components of the RNA-sensing retinoic acid-inducible gene (RIG)-like receptor (RLR) signaling pathway to block antiviral type I interferon responses. Mechanistically, σ3 inhibits RIG-I and melanoma differentiation-associated gene 5 expression is independent of its inhibitory effect on MAVS. Overall, we demonstrate that the MRV σ3 protein plays a vital role in negatively regulating the RLR signaling pathway to inhibit antiviral responses. This enables MRV to evade host defenses to facilitate its own replication providing a target for the development of effective antiviral drugs against MRV.
Mammalian orthoreovirus (MRV) is an important zoonotic pathogen, but the regulatory role of its viral proteins in retinoic acid-inducible gene-like receptor (RLR)-mediated antiviral responses is still poorly understood. Herein, we show that MRV σ3 protein co-localizes with mitochondrial antiviral signaling protein (MAVS) in the mitochondria and promotes the mitochondria-mediated intrinsic apoptotic pathway to cleave and consequently degrade MAVS. Furthermore, tryptophan at position 133 of σ3 protein plays a key role in the degradation of MAVS. Importantly, we show that MRV outer capsid protein σ3 is a key factor in antagonizing RLR-mediated antiviral responses, providing evidence to better unravel the infection and transmission mechanisms of MRV.
To ensure model accuracy, the model parameters in the equivalent circuit model (ECM) are updated frequently with varying state of health (SOH) and state of charge (SOC). In this work, the parameter ...sensitivity of the 2RC model with one-state hysteresis (2RCH) is investigated to determine the crucial parameters. Firstly, the model parameters of 2RCH is identified using particle swarm optimization under dynamic working conditions. Secondly, the sensitivity analysis of parameters in 2RCH for two types of batteries is qualitatively examined using the one-factor-at-a-time method. Thirdly, a simplified model, in which the crucial parameters with high sensitivities are updated with SOC and SOH, while the other parameters retain their initial values, is proposed to ensure model accuracy while reducing computational complexity greatly. Finally, SOC estimation based on the simplified ECM for two types of batteries over the whole SOC range under different SOHs is performed using the extended Kalman filter. The experimental results show that the SOC accuracy obtained by updating the crucial parameters is almost the same as that obtained by updating all parameters. The simplified model is beneficial to avoid unnecessary repeated calculation of model parameters for different SOC and SOH ranges in the SOC estimation.
•SA of model parameters of ECM is conducted to propose a simplified model.•Crucial model parameters over the whole SOC range under different aging degrees are determined.•SOC estimation is performed using the extended Kalman filter based on the simplified ECM.•Effectiveness of the proposed model is verified by experiments on two types of batteries.
Encephalomyocarditis virus (EMCV) is a zoonotic pathogen that has a wide spectrum of host range. The virus has been discovered on swine farms worldwide and can cause acute fatal myocarditis in ...piglets and reproductive disorders in sows. Although EMCV infection has been documented in farmed pigs in China, seroprevalence in humans has not been reported. In this study, we conducted nationwide serological surveys for EMCV in humans and farmed pigs in China in 2013, by the use of a double antigen sandwich ELISA method. A total of 3305 serum samples from healthy people were obtained from seven geographical regions in China, of which 1010 samples (30.56 %) were positive for EMCV antibodies. The overall seroprevalence for EMCV in the age groups of 0–20, 21–40, 41–60 and >60 years were 13.5 %, 30.25 %, 36.83 % and 38.71 % respectively, showing a tendency of increasing with age (P = 0.000). A total of 3470 serum samples from farmed pigs were collected and tested for antibodies to EMCV. A high seroprevalence of 77 % was recorded, and significant regional differences were observed. It was concluded that people and pigs in China were commonly infected by EMCV. In addition, in order to characterize changes of seroprevalence during natural EMCV infection in pigs, 240 serial serum samples were collected from 30 pigs (at 0, 15, 30, 60, 75, 90, 120, and 150 days of age) in a farrow-to-finish farm in China. The data showed that there were two EMCV antibody peaks: the first peak appeared at day 30, followed by a decrease in EMCV antibody titer, and the second occurred after day 75. Thus, the most susceptible period of pigs for EMCV infection was between day 30 and day 75 of age.
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