• <tr id="yyy80"></tr>
  • <sup id="yyy80"></sup>
  • <tfoot id="yyy80"><noscript id="yyy80"></noscript></tfoot>
  • 99热精品在线国产_美女午夜性视频免费_国产精品国产高清国产av_av欧美777_自拍偷自拍亚洲精品老妇_亚洲熟女精品中文字幕_www日本黄色视频网_国产精品野战在线观看 ?

    Review on Li-insertion/extraction Mechanisms of LiFePO4 Cathode Materials①

    2019-01-05 08:07:42WUYiFngCHONGShoKunLIUYongNingGUOShengWuBAILiFengLIChengShn
    結(jié)構(gòu)化學(xué) 2018年12期

    WU Yi-Fng CHONG Sho-Kun LIU Yong-Ning GUO Sheng-Wu BAI Li-Feng LI Cheng-Shn

    ?

    Review on Li-insertion/extraction Mechanisms of LiFePO4Cathode Materials①

    WU Yi-FangaCHONG Shao-KunbLIU Yong-Ningb②GUO Sheng-WubBAI Li-FengaLI Cheng-Shana

    a(710016)b(710049)

    The work distills the main mechanisms during the lithium insertion/extraction of LiFePO4cathode materials. The “diffusion-controlled” and “phase-boundary controlled” mechanism are especially illustrated. Meanwhile, some recent observation and analyses byoron the Li-insertion/extraction of LiFePO4are summarized and prospected.

    Li-ion battery, LiFePO4, Li-insertion/extraction, mechanism, review;

    1 INTRODUCTION

    Lithium iron phosphate (LiFePO4) has become one of the most promising Li-ion battery cathode materials due to its high safety performance, long cycle life, good platform performance, low cost and environmental friendly[1-11], which is of great signifi- cance for the development of electric vehicle industry[12-13].

    Although considerable progress has been made in the development and production of the power battery of LiFePO4, and it has gradually entered the practical orbit, its price is still high, and the high rate charge/discharge capability still needs to be further improved[14-32]. For example, when LiFePO4battery is used in electric vehicles, its power cannot be compared with that of traditional fuel engines, which influences the journey, top speed, acceleration and climbing capabilities of electric vehicles.

    In order to promote the development of LiFePO4battery and improve its high rate charge/discharge capability, it is necessary to study the mechanism of Li-insertion/extraction of LiFePO4. The mechanism involves the complex process of physical chemistry and reaction kinetics, so in-depth study and unders- tanding of its basic behavior will greatly help to improve the rate capability of LiFePO4cathode materials.

    2 MAINSTREAM VIEWS

    In this work, we illustrate two main mechanisms including the “diffusion-controlled”and “phase- boundary controlled” mechanisms.

    2. 1 Diffusion-controlled mechanism

    In this view, the mechanism of Li-insertion/extrac- tion of LiFePO4is “diffusion controlled” model. The phase transition of lithium follows the Radial model or Mosaic model in the Li-insertion/extraction pro- cess[33], that is, the shell of one phase contains the core of another phase, and diffusion occurs throu- ghout the shell moving along the interface. Com- pared with the Radial model, the Mosaic model thinks the Li-insertion/extraction can occur anywhere within a LiFePO4particle. Fig. 1 (a) and (b) show the schematic representations of two possible models (Radial model or Mosaic model) for Li-inser- tion/extraction in a single particle of a LiFePO4during charging and discharging.

    In the “diffusion-controlled” model, one of the most compelling evidences is the result of tempera- ture-controlled XRD spectrum, indicating that LiFePO4exhibits thermally activated solid-solution behavior in the composition range[34]. As shown in Fig. 2, the phases of Li1–yFePO4and LiFePO4at room temperature present the broadening at 210 ℃, and then become completely solid solution at 290 ℃.

    Fig. 1. Diffusion-controlled type (a) a “radial model” (b) a “mosaic model”

    Fig. 2. Temperature-controlled XRD patterns (Co) of Li0.68FePO4under N2

    Another strong evidence is the result of tempera- ture-controlled M?ssbauer spectrum[35]. Some deli- thium samples were carried out, suggesting the solid solution marked with blue line increased, accompa- nied by the reduction of the mother source Fe2+and Fe3+at elevated temperature (Fig. 3). Both studies found solid solution phases appear in their samples, implying that the Li-insertion/extraction is controlled by the diffusion related to the concentration gradient.

    Malik[36]proposed a single-phase dynamic model of the phase transition of LiFePO4using the first principle and Monte Carlo method (Fig. 4). They reported that LiFePO4might be embedded in a solid solution based on the free energy calculation of the equilibrium state, supporting the “diffusion-con- trolled” model. Furthermore, although the two-phase equilibrium characteristics of the LiFePO4and FePO4phases are obvious for some Li-insertion of LiFePO4, the phase transition kinetics of LiFePO4may exhibit an alternative single phase transition, which can occur at a very low overvoltage without nucleation and growth. Since it can occur at very low overvol- tage, the single-phase kinetic model explains good LiFePO4has excellent rate capability.

    Fig. 3. Temperature-dependent M?ssbauer spectra of Li0.55FePO4. The solid lines (green, Fe2+; red, Fe3+; blue, solid solution) are individual components that contribute to the overall fitting of the spectra. Transformation of each of the two-phase samples into LixFePO4single phases is initiated at 200 oC, and completed at 350 oC[38]

    Fig. 4. Free energy and atomic configurations along the single-phase LiFePO4transformation path. (a) Zero-temperature mixing energies (black circles) calculated from the first principles of 245 different Li/vacancy and electron/hole configurations in LiFePO4(0≤≤1) show the existence of several low formation energy structures. (b) Snapshots of Li (green atoms) and Fe2+(brown atoms) configurations in Monte Carlo simulationsat room temperature forLi= 0:2, 0.4, 0.6 and 0.8 show the succession of single-phase states with some local ordering[39]

    2. 2 Phase-boundary controlled mechanism

    Although the above model can perfectly explain the charging/discharging of LiFePO4battery, it is questioned by another view of “phase-boundary controlled”. This is mainly because some researchers observed that FePO4domain was found in some LiFePO4particles in Li-insertion/extraction process, and the interface area was not the solid solution, but the superposition of LiFePO4and FePO4phases.

    Based on these observations and analysis, some alternative phase-interface controlled mechanisms, such as the spinodal-decomposition mechanism[37]and the domino-cascade mechanism[38], were pro- posed, as marked in Figs. 5 and 6, respectively. In the amplitude modulation decomposition, the component at the peak is higher than the average one, whereas the component at the trough is lower than the average one. However, the crystal structures in the Li-rich and Li-poor regions were the same, except that the composition fluctuated slightly. Both mechanisms consider that the Li-ion insertion or extraction involves the coordinated movement of lithium ions throughout the phase interface, and the main difference between them is the velocity of the phase interface. The domino-cascade mechanism held the phase interface was moving rapidly, and the mixed phases of LiFePO4and FePO4were not detected in some delithiated particles. However, the velocity of phase interface is relatively low in the spinodal- decomposition mechanism, and multi-domains and phase interfaces can be observed in partially deli- thiated particles.

    Fig. 5. Schematic view of the ‘Spinodal-decomposition’ mechanism. (a) An intermediate length scale grows the fastest and dominates the pattern of phase separation. (b) A long-wavelength fluctuation grows relatively slowly, as the distances that the material has to diffuse from troughs to peaks are relatively large. (c) Too much new interface is created, with a correspondingly large free energy penalty

    Fig. 6. Schematic view of the ‘domino-cascade’ mechanism for the lithium deintercalation/intercalation mechanism in a LiFePO4crystallite. (a) Scheme showing a view of the strains occurring during lithium deintercalation. (b) Layered view of the lithium deintercalation/intercalation mechanism in a LiFePO4crystalline

    One of the strongest evidences supporting the “phase-boundary controlled” mechanisms is the high-resolution electron energy loss spectroscopy (EELS, O-K edge) of the delithium sample Li0.45FePO4[39], suggesting the spectral line of the interface is a linear combination of LiFePO4and FePO4spectral lines. Hence, we can deduce that the interface is a two-phase coexistence region, rather than a solid solution, as presented in Fig. 7. It can also be seen from Fig. 7 that the interface width of LiFePO4and FePO4phases is 12 nm.

    Fig. 7. STEM HAADF image of the chemically delithiated sample Li0.45FePO4with the analysis line and the 3D representation of EELS spectra recorded along that line. Note that the EELS spectra of the interface are represented in red

    Another strong evidence is the high-resolution transmission electron microscopy (HRTEM) spec- trum[40], which shows multi-domains and phase interfaces can be observed in partially delithiated LiFePO4particles. As shown in Fig. 8, a small angular grain boundary along theaxis is formed because of the dislocation motion, indicating the dynamic process is caused by the dislocation and the movement of nucleation front, rather than the diffusion related to the concentration gradient.

    Fig. 8. HRTEM image of a partially delithiated LiFePO4particle showing a LiFePO4domain (LFP) in theplane surrounded by FePO4phase (FP) with narrow interface layers consisting of two crystal phases

    Allen[41]further proved the viewpoint of “phase- boundary controlled” with the Avrami-Johnson- Mehl-Eroofev equation to analyze the delithiated dynamics.

    = 1 – exp(–)(1)

    Whereis the volume fraction of LiFePO4,is the rate constant parameter, andis an exponent whose value is dependent upon the geometry of the transformation. The Avrami exponentincreases with the dimensionality of growth. Typically, anvalue of 1~2 is indicative of one-dimensional growth. Allen obtained the Avrami exponent value of 1, elucidating the phase transition of Li-inser- tion/extraction follows the one-dimensional growth mechanism and belongs to the “phase-boundary controlled” type.

    The XPS spectra[42]also showed that, upon char- ging, the ratio of Fe3+/Fe2+on the surface of LiFePO4continued to increase, rather than presenting an unusually large rate of Fe3+/Fe2+, which conforms to the rule of “phase-boundary controlled” model. This can be explained by the fact that most Fe3+ionsshould be gathered on the surface of LiFePO4according to the core-shell model. A large rate of Fe3+/Fe2+should appear in the XPS analysis, but as noted above, the results are not expected. Fig. 9 shows the schematic diagram of XPS spectra according to different models.

    Fig. 9. Scheme to describe the expected XPS spectra according to different models[44]

    Recently, Bai[43]also proposed a surface-limited Li-insertion model for anisotropic nanoparticles in non-equilibrium state with the phase field, and pre- dicted that phase separation could be inhibited at a certain critical current. Due to the reaction limitation of nanoparticles, if the applied and exchange currents are at the same order of magnitude, the surface overpotential of the nanoparticles can easily exceed the voltage limitation of the solid solution to prevent the thermodynamic driving force of phase separation. Phase separation will play a major role only if the current is low in very large particles. The amplitude- modulated decomposition or nucleation causes the phase boundary to move at a small current. When the current density is higher than a certain critical one, the amplitude modulation decomposition disappears and the particles are evenly filled, which can explain the high multiplier performance and long cycle life of nanometer LiFePO4. The theory holds that in the non-equilibrium state, the “diffusion-controlled” model plays a leading role in the nanoparticles, whereas the “phase-boundary controlled” model plays a dominate role in micron particles scale with a small rate discharge.

    The above viewpoint was further confirmed by Oyama[44]using the potential step method and the calculation of Avrami exponent in the Kolmogorov- Johnson-Mehl-Avrami (KJMA) model. The results indicated that Li-insertion/extraction depends on the magnitude of the potential step and particle size, as shown in Fig. 10. When the particle size (< 100 nm) is small while the potential step (< 150) mV is large, the chronoamperometryresult shows the current monotonically declines, which is consistent with the KJMA model, suggesting that the Li-insertion/extrac- tion pathway is a non-equilibrium solid solution way. When the particle size of 203 nm is large while the potential step of 10 mV is small, the chronoam- perometry data show that the current increases at the moment and then gradually decreases, implying the Li-insertion/extraction is dominated by the electrode dynamics with the growth of new phase nuclei. Meanwhile, the chronoamperometry diagram is fitted with the KJMA model, and the Avrami exponent= 1conforms to the one-dimensional phase boundary model. Therefore, in this mechanism, in the non- equilibrium state, the Li-insertion/extraction mode of spherical particles of < 100 nm is the “diffusion- controlled” model dominated by solid solution, whereas the ones of > 100 nm are fitted with the “phase-boundary controlled” model.

    Fig. 10. Chemical potential profiles of LiFePO4, assuming a single phase reaction (blue solid line) and a two-phase reaction (blue dashed line). Symbols O, A1, A2, A3, and B denote the equilibrium states at different potentials (E0, E1, and E2). The white circles indicate spinodal points. In a potential region between two spinodal points (Esp1 and Esp2), there exists a metastable solid solution (A1) as well as a stable one (A3)[47]

    3 RECENT ADVANCES

    In recent years, the researches on the mechanism of Li-insertion/extraction mechanism of LiFePO4have never been stopped, especially with the deve- lopment ofobservation technique, the mecha- nism has been further investigated.

    Gu[45]observed in situ for the first time that lithium was intercalated during the extraction process on the atomic scale with the aberration-corrected annular-bright-field (ABF) STEM (Fig. 11). The results show that the rest of Li ions occupies per- fectly the interlayer atoms along theaxis in the partial delithium nanowire (electrochemical deli- thium,= 65nm) LiFePO4, which is more inclined to the previously proposed “diffusion-controlled” mechanism.

    Fig. 11. Aberration-corrected annular-bright-field (ABF) STEM micrographs showing Li ions of partially delithiated LiFePO4at every other row (a) Pristine material with the atomic structure of LiFePO4shown as inset; (b) Fully charged state with the atomic structure of FePO4shown for comparison; and (c) Half charged state showing the Li staging[48]

    Chang[46]found that the phase transition from FePO4to LiFePO4(or from LiFePO4to FePO4) was hysteretic during the extraction process of lithium of LiFePO4. Specially, this hysteretic behavior was also present at low medium magnification (C/10~1C) withSynchronous XRD spectrum. The inset in Fig. 12 shows the XRD peak intensities of LiFePO4(020) (■) and FePO4(020) (□) versus the measurement number in the process of discharging- rest-charging-rest (D-R-C-R). It can be seen that the FePO4phase is converted to LiFePO4phase until it is near the end of discharge. Similarly, LiFePO4phase is converted to FePO4until near the end of charge. The results indicate that, even in the metastable crystal structure (the charge/discharge is under non-equilibrium conditions), the characteristics of two phases of Li-insertion/extraction are obvious, which is more in line with the “phase-boundary controlled” model.

    Fig. 12.synchrotron XRD patterns for charge/discharge test of the cell with an intermittent rest period. The subscripts F and L indicate, respectively, the reflections from the FePO4-and LiFePO4-structures. The bold curves mark the onset of different stages (C for charge; D, discharge; R, rest) within a test cycle. The inset shows the XRD peak intensities of LiFePO4(020) (■) and FePO4(020) (□) versus the measurement number[49]

    Wang[47]studied the LiFePO4samples with 0.6- micron usingX-ray diffraction (XRD),X-ray absorption spectrometry (XAS) and pre- positional soft X-ray absorption spectrometry. As shown in Fig. 13, the contents of LiFePO4and FePO4phases deviated significantly from the linear region shown in the dotted line during the charging process through the Rietveldrefinement. This indicates that the phase transition lags behind the voltage curve in the partially delithiated Li1–FePO4. Studies on the combination ofand prepositional methods show that the phase transition is related to not only the composition of Li, but also the different nuclea- tion and growth mechanism of the new FePO4phase during charging, which supports the “phase-boun- dary controlled” model.

    Fig. 13. Contents of LiFePO4and FePO4calculated by Rietveld refinement.in Li1-FePO4[50]

    Wang[48]investigated the Li-insertion/extraction mechanism of multi- and single-particle systems byTXM-XANES spectrum. As shown in Fig. 14, for multi-particle nanometer FePO4aggre- gation, the transition from LiFePO4to FePO4phase is uniform at the slow delithium rate of 0.1 C, and more LiFePO4and FePO4exist in the form of mixed phase. These conclusions support the solid solution viewpoint where phase separation is inhibited in the Li-insertion/extraction process, which agrees with the “diffusion-controlled” mechanism. However, more LiFePO4and FePO4phases co-existed in the transformation process at the high delithium rate of 5 C, supporting the “phase-boundary controlled” mechanism. For the single-particle system, as shown in Fig. 15, the two phases of FePO4and LiFePO4co-existed in the micron scale particles revealed byfull-field TXM, and their mixed phases were not detected at the delithium rates of 0.02 and 1 C, respectively, supporting “domino-cascade” model of the “phase-boundary controlled” mechanism. In addition, the results also show the Li-inser- tion/extraction mechanism of LiFePO4is closely related to not only the particle size, but also the test conditions of sample such as discharge rate.

    Fig. 14. Schematic illustration for multi-particle LiFePO4system. Phase transformation mechanism and intercalation pathway at fast and slow charging rates for multi-particle LiFePO4system. Each circle represents a multi-particle nano-LFP aggregation, not single particle[51]

    Fig. 15. Schematic illustration for single-particle LiFePO4system. The models a and b and the corresponding actual particles represent the two typical delithiation processes revealed byfull-field transmission X-ray microscopy (TXM)[51]

    Sharma[49]concluded the coexistence of solid solu- tion and two-phase transition behavior in the non- equilibrium samples of deep discharge usingneutron powder diffraction (NPD). In Fig. 16, the Rietveld refinement parameters of LiFePO4phase are represented by green cross, while those of FePO4phase are represented by black cross. The vertical black line is the starting point of solid solution reac- tion, while the vertical purple line is the transition curve from Li1–FePO to LiFePO4phases in chronological order. The shadow region is a two- phase region. This study shows the Li-inser- tion/extraction mechanism of LiFePO4is closely related to the state of the sample, which may be different when the sample is in equilibrium state and non-equilibrium state.

    Fig. 16.neutron powder diffraction (NPD) data of the Li||LiFePO4battery and Rietveld-derived lattice parameters of the cathode[52]

    Yu[50]investigated the Li-insertion/extraction mechanism of LiFePO4for the ellipsoid samples (300 nm) under the chemical and electrochemical delithium at different time (0.1~60 C) withXAS. Meanwhile, they obtained the value 1 of the Avrami exponent with the Avrami-Johnson-Mehl- Eroofev equation, which conforms to the one-dimen- sional “phase-boundary controlled” mechanism.

    Niu[51]studied the dynamics of LiFePO4electrode of nanowire (200~400 nm) at the discharge rate of 1 C in the delithium process byHRTEM. They observed in situ the sub-lattice disordered solid solution area (SSZ) of lithium, which was completely different from the sharp LFP|FP boundary observed under other conditions. The solid solution region with a scale about 20 nm is so stable that it can exist for hundreds of seconds at room temperature. Since there is no dislocation in the solid solution area, greater cycle life and higher rate capability can be expected, which implies that the disordered solid solution area may dominate phase transition behavior in the non-equilibrium state (when higher current or voltage is used). The results indicate the sample of this scale obeys the “diffusion controlled” mecha- nism under non-equilibrium conditions.

    Lim[52]observed the kinetic map of Li compo- sition distribution and insertion rate of the flaky LiFePO4particles (1 μm in wideness and 150 nm in thickness) using anscanning transmission X-ray microscopy(STXM). As shown in Fig. 17, the phase separation was inhibited as the lithium rate increase, and the insertion pathways of lithium converted from “phase-boundary controlled” (under 0.2 C rate) to “non-uniform domain area” and then to “uniform solid solution” (under 2 C rate). When the lithium rate increased to 2 C, the Li component distribution observedindicated Li is uniformly inserted into the particle, namely, the composition difference between each particle is very small, which is considered to be a solid solution behavior. The conclusion is in line with the “diffusion controlled” mechanism. The depen- dence of composition distribution on the ratio makes it easier to form uniform solid solution phase in the process of lithium formation, while the process of delithium is less uniform. The interaction between lithium composition and surface reaction rate controls the kinetics and uniformity of the insertion reaction of Li ions at the solid-liquid interface, and then the rate capability and cycle life of Li-ion battery are determined.

    Fig. 17. Scheme of the insertion pathway as a function of the lithiation rate[55]

    In addition, Lim[52]also observed the Li com- position distribution of partial delithium samples at 1 C rate cycle1 and 12 h relaxation under theexperiment. The results suggest that the phase boundary between the Li-rich and Li-lean regions is obvious, indicating the phase separation under the influence of elastic strain dominates the Li distri- bution of the equilibrium state, namely, the Li- insertion/extraction mechanism in equilibrium state is more consistent with the “phase-boundary controlled” one.

    Li[53]also employed the latestXRD to confirm when the dimension of LiFePO4in the crystal direction [100] was reduced to the width of equilibrium phase boundary (about 12 nm), and the solid solubility of Li can increase in the LiFePO4and Li1?βFePO4phases, that is, the solid solution limitation of Li increases while the miscibility gap decreases. This viewpoint also supports the “diffusion-controlled” mechanism, and confirms the miscibility gap of Li has high orientation and dependency.

    In conclusion, the researches have demonstrated a variety of possibilities for the phase transition mechanisms during the Li-insertion/extraction of LiFePO4. In most cases, the improvement of material performance depends on the in-depth study of the material foundation and deep understanding of the material essence. Therefore, it has a profound significance to investigate the Li-insertion/extraction of LiFePO4mechanism.

    4 PROSPECTS

    The study on the mechanism of the Li-inser- tion/extraction of LiFePO4, from the initial theore- tical model to the observation and analysis oftechnique, has experienced unprecedented progress, and the experimental research is also more direct and in-depth. It should be noted that the mechanism of Li-insertion/extraction is closely relatedto many factors such as grain size of samples (nano or micro), morphology (spherical, lamellar or wire rod), the state of the sample (equilibrium or non-equilibrium), the test conditions (rate of Li-insertion/extraction), the way of Li-insertion/extraction (chemicals or electrochemical), and so on. Therefore, it does not simply determine the possible mechanism of Li-insertion/extraction, but it is necessary to combine the state and experimental conditions of the sample for analysis to reach a systematic and valuable con- clusion. For example, in non-equilibrium conditions, the samples with the nanometer scale are dominated by the “diffusion-controlled” mechanism. The samples with micron-sized LiFePO4may follow the different mechanisms at different rates of Li-inser- tion/extraction. As another example, the properties of LiFePO4may have a strong correlation with the temperature. At low temperature, lithium ions in the electrolyte slowly transfer, the impedance of surface membrane on the electrode/electrolyte interface increases, thus the charge transfer impedance on the electrode surface increases, and the diffusion of lithium ions in the electrode is slow. Therefore, the Li-insertion/extraction mechanisms of LiFePO4at low temperature may be different from the ones at normal temperature, which will be a valuable research topic in the future.

    In recent years, the development ofobservation technique has brought a new opportunity for the research on the Li-insertion/extraction mechanisms of LiFePO4. This method is more intuitive, and can directly observe the extraction mode of lithium ions at the atomic level, which is the biggest progress in the research on the Li-inser- tion/extraction mechanisms. If theobservation technique is used to study systematically the samples with different grain sizes and morphology, sample states, test conditions, and Li-insertion/extraction methods, more comprehensive and profound understanding will be obtained.

    At present, the theoretical research on Li-inser- tion/extraction mechanisms of LiFePO4is still inadequate. It is rare to study the mechanisms on different sample states and experimental conditions, which will become the focus of our future research.

    (1) Padhi, A. K.; Nanjundaswamy, K. S.; Goodenough, J. B. Phospho-olivines as positive-electrode materials for rechargeable lithium batteries.1997, 144, 1188-1194.

    (2) Ritchie, A.; Howard, W. Recent developments and likely advances in lithium-ion batteries.2006, 162, 809-812.

    (3) Tarascon, J. M.; Armand, M. Issues and challenges facing rechargeable lithium batteries.,–367.

    (4) Whittingham, M. S. Materials challenges facing electrical energy storage.. 2008, 33, 411–419.

    (5) Ohzuku, T.; Brodd, R. J. An overview of positive-electrode materials for advanced lithium-ion batteries.. ,–456.

    (6) Jugovic, D.; Uskokovic, D. A review of recent developments in the synthesis procedures of lithium iron phosphate powders.2009, 190, 538–544.

    (7) Scrosati, B.; Garche, J. Lithium batteries, status, prospects and future.2010, 195, 2419–2430.

    (8) Yu, F.; Zhang, L. L.; Lai, L. F. High electrochemical performance of LiFePO4cathode material viamicrowave exfoliated

    graphene oxide.2015, 151, 240–248.

    (9) Meethong, N.; Kao, Y. H.; Speakman, S. A.Aliovalent substitutions in olivine lithium iron phosphate and impact on structure and properties.2009, 19, 1060–1070.

    (10) Fan, Q.; Lei, L.; Sun, Y.Biotemplated synthesis of LiFePO4/C matrixes for the conductive agent-free cathode of lithium ion batteries.. 2013, 244, 702–706.

    (11) Yang, Z. G.; Zhang, J. L.; Kintner-Meyer, M. C. W. Electrochemical energy storage for green grid.2011, 111, 3577–3613.

    (12) Tarascon, J. M.; Armand, M. Issues and challenges facing rechargeable lithium batteries.2001, 414, 359–367.

    (13) Kim, S.; Zhang, Z. X.; Wang, S. L. Electrochemical and structural investigation of the mechanism of irreversibility in Li3V2(PO4)3cathodes.2016, 120, 7005–7012.

    (14) Dominko, R.; Gaberscek, M.; Drofenik, J. The role of carbon black distribution in cathodes for Li ion batteries.2003, 119–121, 770–773.

    (15) Chung, S. Y.; Bloking, J. T.; Chiang, Y. T. Electronically conductive phospho-olivines as lithium storage electrodes.. 2002, 1, 123–128.

    (16) Yu, F.; Zhang, J.; Yang, Y. Preparation and characterization of mesoporous LiFePO4/C microsphere by spray drying assisted template method.2009, 189, 794–797.

    (17) Delacourt, C.; Poizot, P.; Levasseur, S.Size effects on carbon-free LiFePO4powders, the key to superior energy density.. 2006, 9, A352–A355.

    (18) Zane, D.; Carewska, M.; Scaccia, S. Factor affecting rate performance of undoped LiFePO4.2004, 49, 4259–4271.

    (19) Chen, Z.; Dahn, J. R.Reducing carbon in LiFePO4/C? composite electrodes to maximize specific energy, volumetric energy, and tap density.2002, 149, A1184–A1189.

    (20) Kim, D. H.; Kim, J. Synthesis of LiFePO4nanoparticles in polyol medium and their electrochemical properties.2006, 9, A439–A442.

    (21) Gibot, P.; Casas-Cabanas, M.; Laffont, L.Room-temperature single-phase Li insertion/extraction in nanoscale LiFePO4.2008, 7, 741–747.

    (22) Ravet, N.; Goodenough, J. B.; Besner, S. Improved iron based cathode material.1999, Honolulu, 99-2HI, Abstract 127. f

    (23) Gong, C. L.; Xue, Z. G.; Wen, S. Advanced carbon materials/olivine LiFePO4composites cathode for lithium ion batteries.2016, 318, 93–112.

    (24) Gong, H.; Xue, H. R.; Wang, T.synthesis of monodisperse micro-nanospherical LiFePO4/carbon cathode composites for lithium-ion batteries.2016, 318, 220–227.

    (25) Zhu, J. N.; Li, W. C.; Cheng, F. Li-ion battery cathode by a two-stage microwave solvothermal process.2015, 26, 13920–13925.

    (26) Wang, Y. G.; Wang, Y. R.; Hosono, E. J.The design of a LiFePO4/carbon nanocomposite with a core-shell structure and its synthesis by an in situ polymerization restriction method.2008, 47, 7461–7465.

    (27) Wu, X. L.; Jiang, L. Y.; Cao, F. F. LiFePO4nanoparticles embedded in a nanoporous carbon matrix, superior cathode material for electrochemical energy-storage devices.2009, 21, 2710–2714.

    (28) Ma, Z.; Shao, G.; Fan, Y. Tunable morphology synthesis of LiFePO4nanoparticles as cathode materials for lithium ion batteries.2014, 6, 9236–9244.

    (29) Ma, Z.; Fan, Y.; Shao, G.catalytic synthesis of high-graphitized carbon-coated LiFePO4nanoplates for superior Li-Ion battery cathodes.2015, 7, 2937–2943.

    (30) Wang, G.; Ma, Z.; Shao, G. Synthesis of LiFePO4@carbon nanotube core-shell nanowires with a high-energy efficient method for superior lithium ion battery cathodes.2015, 291, 209–214.

    (31) Liu, L.; Zhang, H. J.; Chen, X. Unique synthesis of sandwiched graphene@(Li0.893Fe0.036)Co(PO4) nanoparticles as high-performance cathode materials for lithium-ion batteries.2015, A3, 12320–12327.

    (32) Sun, P.; Zhang, H.; Shen, K. Preparation of V-doped LiFePO4/C as the optimized cathode material for lithium ion batteries.2015, 15, 2667–2672.

    (33) Andersson, A. S.; Thomas, J. O. The source of first-cycle capacity loss in LiFePO4.2001, 97-98, 498-502.

    (34) Delacourt, C.; Poizot, P.; Tarascon, J. M. The existence of a temperature-driven solid solution in LiFePO4for 0≤≤1.2005, 4, 254-260.

    (35) Eills, B.; Perry, K. L.; Ryan, H. D.Small polaron hopping in LiFePO4solid solutions, coupled lithium-ion and electron mobility.2006, 128, 11416–11422.

    (36) Malik, R.; Zhou, F.; Ceder, G. Kinetics of non-equilibrium lithium incorporation in LiFePO4.2011, 10, 587-590.

    (37) Jones, L. A. R.. Oxford University Press 2002.

    (38) Delmas, C.; Maccario, M.; Croguennec, L. Lithium deintercalation in LiFePO4nanoparticles via a domino-cascade model.2008, 7, 665-671.

    (39) Laffont, L.; Delacourt, C.; Gibot, P. Study of the LiFePO4/FePO4two-phase system by high-resolution electron energy loss spectroscopy.2006, 18, 5520-5529.

    (40) Ramana, C. V.; Mauger, A.; Gendron, F. Study of the Li-insertion/extraction process in LiFePO4/FePO4.2009, 187, 555–564.

    (41) Allen, J. L.; Jow, R. T.; Wolfenstine, J. Kinetic study of the electrochemical FePO4to LiFePO4phase transition.2007, 19, 2108-2111.

    (42) Dedryvère, R.; Maccario, M.; Croguennec, L.X-ray photoelectron spectroscopy investigations of carbon-coated LiFePO4materials.2008, 20, 7164-7170.

    (43) Bai, P.; Cogswell, D. A.; Bazant, M. Z. Suppression of phase separation in LiFePO4nanoparticles during battery discharge.2011, 11, 4890–4896.

    (44) Oyama, G.; Yamada, Y.; Natsui, R. I. Kinetics of nucleation and growth in two-phase electrochemical reaction of LiFePO4.2012, 116, 7306–7311.

    (45) Gu, L.; Zhu, C. B.; Li, H. Direct observation of lithium staging in partially delithiated LiFePO4at atomic resolution.2011, 133, 4661-4663.

    (46) Chang, H. H.; Chang, C. C.; Wu, H. C. Study on dynamics of structural transformation during charge/discharge of LiFePO4cathode2008, 10, 335-339.

    (47) Wang, X. J.; Jaye, C.; Nam, K. W. Investigation of the structural changes in Li1-xFePO4upon charging by synchrotron radiation techniques.2011, 21, 11406-11411.

    (48) Wang, J. J.; Chen-Wiegart, Y. C. K.; Wang, J. In-operando tracking phase transformation evolution of lithium iron phosphate with hard X-ray microscopy.2014, 5, 4570.

    (49) Sharma, N.; Guo, X. W.; Du, G. D.Direct evidence of concurrent solid-solution and two-phase reactions and the nonequilibrium structural evolution of LiFePO4.2012, 134, 7867-7873.

    (50) Yu, X. Q.; Wang, Q.; Zhou, Y. N. High rate delithiation behaviour of LiFePO4studied by quick X-ray absorption spectroscopy.2012, 48, 11537-11539.

    (51) Niu, J. J.; Kushima, A.; Qian, X. F.observation of random solid solution zone in LiFePO4electrode.2014, 14, 4005-4010.

    (52) Lim, J.; Li, Y. Y.; Alsem, D. H. Origin and hysteresis of lithium compositional spatiodynamics within battery primary particles2016, 353, 566-571.

    (53) Li, Z. J.; Yang, J. X.; Li, C. J. Orientation-dependent lithium miscibility gap in LiFePO4.2018, 30, 3, 874-878.

    7 March 2018;

    26 September 2018

    ① This work was supported by the National Natural Science Foundation of China (No. 51504196) and Key Research and Development Plan of Shaanxi Province (No. 2017ZDXM-GY-039)

    . E-mail: wyf7777v@126.com

    10.14102/j.cnki.0254-5861.2011-2000

    人妻夜夜爽99麻豆av| 国产一区二区激情短视频| 久久久久免费精品人妻一区二区| 俄罗斯特黄特色一大片| 日韩精品有码人妻一区| 久久久久国产网址| 91久久精品国产一区二区成人| 国产黄色小视频在线观看| 在线免费观看的www视频| 日日摸夜夜添夜夜添小说| 精品久久久久久久久久久久久| 在线免费十八禁| 一级毛片我不卡| 嫩草影院新地址| 国产精品国产三级国产av玫瑰| 身体一侧抽搐| 人人妻人人澡人人爽人人夜夜 | 久久久久免费精品人妻一区二区| 国产美女午夜福利| 男插女下体视频免费在线播放| 日韩强制内射视频| 色综合亚洲欧美另类图片| 国内少妇人妻偷人精品xxx网站| 老师上课跳d突然被开到最大视频| 1024手机看黄色片| 22中文网久久字幕| 三级男女做爰猛烈吃奶摸视频| 精品一区二区三区av网在线观看| 久久久色成人| 69av精品久久久久久| 色哟哟·www| 亚洲精品成人久久久久久| 国产女主播在线喷水免费视频网站 | 免费看日本二区| 亚洲高清免费不卡视频| 婷婷色综合大香蕉| 久久精品人妻少妇| 一进一出抽搐gif免费好疼| 成人高潮视频无遮挡免费网站| 亚洲人成网站在线观看播放| 亚洲人成网站高清观看| 男女那种视频在线观看| 久久99热6这里只有精品| 久久久久九九精品影院| 亚洲性夜色夜夜综合| av国产免费在线观看| 黄色一级大片看看| 国产午夜精品论理片| 午夜福利成人在线免费观看| 国产片特级美女逼逼视频| 天美传媒精品一区二区| 国产成人福利小说| 成人国产麻豆网| 国产午夜福利久久久久久| 小蜜桃在线观看免费完整版高清| 亚洲成人久久爱视频| 亚洲av成人av| 在线免费观看的www视频| avwww免费| 97人妻精品一区二区三区麻豆| a级一级毛片免费在线观看| 成人性生交大片免费视频hd| 综合色av麻豆| 午夜福利在线在线| 51国产日韩欧美| 18禁在线播放成人免费| 精品熟女少妇av免费看| 少妇熟女aⅴ在线视频| 可以在线观看的亚洲视频| 国产成人影院久久av| 日韩欧美一区二区三区在线观看| 欧美人与善性xxx| 亚洲人成网站在线观看播放| 极品教师在线视频| 99热全是精品| 亚州av有码| 欧美不卡视频在线免费观看| 精品日产1卡2卡| 久久午夜福利片| 国产精品国产三级国产av玫瑰| 午夜影院日韩av| 午夜福利高清视频| 亚洲乱码一区二区免费版| 亚洲真实伦在线观看| 黄片wwwwww| 国内揄拍国产精品人妻在线| 国产一区二区在线观看日韩| 国产不卡一卡二| 在线观看一区二区三区| 久久精品国产自在天天线| 99久久精品热视频| 18禁黄网站禁片免费观看直播| 黄片wwwwww| 久久久久久伊人网av| 久久精品国产亚洲av香蕉五月| 欧美bdsm另类| .国产精品久久| 伦精品一区二区三区| 日韩大尺度精品在线看网址| 可以在线观看的亚洲视频| 日本a在线网址| 精品午夜福利在线看| 一a级毛片在线观看| 悠悠久久av| 久久久久久久久久成人| 午夜精品在线福利| 日韩欧美精品免费久久| 床上黄色一级片| 搡老岳熟女国产| 国产爱豆传媒在线观看| 亚洲电影在线观看av| 伦理电影大哥的女人| 日韩在线高清观看一区二区三区| 99久久成人亚洲精品观看| 午夜激情福利司机影院| 在线观看美女被高潮喷水网站| 色在线成人网| 亚洲电影在线观看av| 亚洲,欧美,日韩| 99精品在免费线老司机午夜| 中文字幕免费在线视频6| 国产精华一区二区三区| 一边摸一边抽搐一进一小说| 欧美bdsm另类| 国产午夜精品久久久久久一区二区三区 | 亚洲国产精品合色在线| 男女那种视频在线观看| 午夜激情福利司机影院| 免费在线观看成人毛片| 可以在线观看的亚洲视频| 最近在线观看免费完整版| 一区二区三区四区激情视频 | 亚洲美女搞黄在线观看 | 久久久国产成人免费| 国模一区二区三区四区视频| 少妇裸体淫交视频免费看高清| 亚洲成人av在线免费| 国产亚洲精品综合一区在线观看| 联通29元200g的流量卡| 成年女人毛片免费观看观看9| 九九热线精品视视频播放| 3wmmmm亚洲av在线观看| 一进一出抽搐gif免费好疼| 欧美绝顶高潮抽搐喷水| 久久久a久久爽久久v久久| 欧美丝袜亚洲另类| 亚洲欧美日韩卡通动漫| 少妇的逼好多水| 淫秽高清视频在线观看| 久久综合国产亚洲精品| 色综合色国产| 亚洲,欧美,日韩| 午夜免费男女啪啪视频观看 | 国产精品一区二区免费欧美| 国产91av在线免费观看| 一边摸一边抽搐一进一小说| 99久久无色码亚洲精品果冻| 深爱激情五月婷婷| 天天躁日日操中文字幕| av在线天堂中文字幕| 最近视频中文字幕2019在线8| 亚洲精品成人久久久久久| 日日啪夜夜撸| 久久久久国产网址| 午夜日韩欧美国产| 三级国产精品欧美在线观看| 在线播放国产精品三级| 又黄又爽又刺激的免费视频.| av在线亚洲专区| 你懂的网址亚洲精品在线观看 | 亚洲va在线va天堂va国产| 麻豆精品久久久久久蜜桃| 老师上课跳d突然被开到最大视频| 午夜日韩欧美国产| 免费av不卡在线播放| 日韩精品青青久久久久久| 国产一区二区在线观看日韩| 色综合站精品国产| 少妇丰满av| 搡老岳熟女国产| 精华霜和精华液先用哪个| 免费高清视频大片| 噜噜噜噜噜久久久久久91| 久久韩国三级中文字幕| 亚洲国产精品成人久久小说 | 美女高潮的动态| 午夜精品一区二区三区免费看| 中文字幕久久专区| 国产精品野战在线观看| 亚洲无线观看免费| 一个人看的www免费观看视频| 亚洲经典国产精华液单| 又粗又爽又猛毛片免费看| 亚洲成人精品中文字幕电影| 黑人高潮一二区| 国产一区二区激情短视频| 69人妻影院| 国模一区二区三区四区视频| 国产片特级美女逼逼视频| 桃色一区二区三区在线观看| 成人一区二区视频在线观看| 一个人看的www免费观看视频| 91av网一区二区| 久久久久久久久大av| av视频在线观看入口| 99热6这里只有精品| 亚洲av成人精品一区久久| 日韩一区二区视频免费看| 尾随美女入室| 最近最新中文字幕大全电影3| 精品午夜福利视频在线观看一区| 三级毛片av免费| 精品99又大又爽又粗少妇毛片| av在线老鸭窝| 搡老熟女国产l中国老女人| 亚洲精品一卡2卡三卡4卡5卡| 少妇被粗大猛烈的视频| 午夜亚洲福利在线播放| 蜜桃久久精品国产亚洲av| 黄色日韩在线| 久久久久久九九精品二区国产| 国产av在哪里看| 久久精品国产亚洲av香蕉五月| 波多野结衣高清作品| av在线天堂中文字幕| 中国美女看黄片| 三级毛片av免费| 直男gayav资源| 日本三级黄在线观看| 国产色爽女视频免费观看| 国产亚洲精品av在线| 国语自产精品视频在线第100页| 中文字幕av成人在线电影| 婷婷精品国产亚洲av在线| 搡女人真爽免费视频火全软件 | 日本免费a在线| 日本欧美国产在线视频| 久久99热6这里只有精品| 波多野结衣巨乳人妻| 女同久久另类99精品国产91| 午夜福利18| 国产国拍精品亚洲av在线观看| 最近视频中文字幕2019在线8| 男人和女人高潮做爰伦理| 亚洲精品乱码久久久v下载方式| 国内精品久久久久精免费| 欧美区成人在线视频| av在线观看视频网站免费| 亚洲精品一卡2卡三卡4卡5卡| 亚洲乱码一区二区免费版| 成人漫画全彩无遮挡| 亚洲欧美清纯卡通| 一级av片app| 国产精品人妻久久久久久| .国产精品久久| 免费看a级黄色片| 天堂√8在线中文| 精品人妻熟女av久视频| 国产av麻豆久久久久久久| 成人av一区二区三区在线看| 久久亚洲精品不卡| 国产国拍精品亚洲av在线观看| 国产黄色小视频在线观看| 午夜激情欧美在线| 天堂网av新在线| 亚洲成人av在线免费| 国产精品无大码| 精品久久国产蜜桃| 国产精品久久视频播放| 乱系列少妇在线播放| 久久精品国产99精品国产亚洲性色| 十八禁国产超污无遮挡网站| 中国美白少妇内射xxxbb| 在线观看免费视频日本深夜| 在线观看av片永久免费下载| 日本五十路高清| 丰满人妻一区二区三区视频av| 少妇裸体淫交视频免费看高清| 好男人在线观看高清免费视频| 如何舔出高潮| 18+在线观看网站| 寂寞人妻少妇视频99o| 精华霜和精华液先用哪个| 久久精品影院6| 一本久久中文字幕| 国产久久久一区二区三区| 日韩,欧美,国产一区二区三区 | 毛片一级片免费看久久久久| 非洲黑人性xxxx精品又粗又长| 国产成人a区在线观看| 精品少妇黑人巨大在线播放 | 美女 人体艺术 gogo| 看片在线看免费视频| 国内精品美女久久久久久| 在线免费观看的www视频| 亚洲婷婷狠狠爱综合网| 蜜桃久久精品国产亚洲av| 免费看光身美女| 国产三级在线视频| 91久久精品国产一区二区三区| 午夜精品在线福利| 成人一区二区视频在线观看| 日韩,欧美,国产一区二区三区 | 韩国av在线不卡| 大又大粗又爽又黄少妇毛片口| 亚洲专区国产一区二区| 色噜噜av男人的天堂激情| av在线播放精品| 欧美中文日本在线观看视频| 国产在线男女| 国产高潮美女av| АⅤ资源中文在线天堂| 高清毛片免费观看视频网站| 99热这里只有精品一区| 熟妇人妻久久中文字幕3abv| 亚洲真实伦在线观看| 在线观看美女被高潮喷水网站| 国产91av在线免费观看| 成人亚洲欧美一区二区av| 免费高清视频大片| 一进一出抽搐动态| 免费av观看视频| 亚洲精品一区av在线观看| 亚洲av一区综合| 校园春色视频在线观看| 老熟妇乱子伦视频在线观看| 在线观看一区二区三区| 欧美在线一区亚洲| 99久国产av精品| 国产白丝娇喘喷水9色精品| 日韩人妻高清精品专区| 亚洲精品国产成人久久av| 在现免费观看毛片| 亚洲精华国产精华液的使用体验 | 欧美又色又爽又黄视频| 国产精品女同一区二区软件| 干丝袜人妻中文字幕| 色综合色国产| 97超视频在线观看视频| 国产欧美日韩一区二区精品| 99热精品在线国产| av天堂在线播放| 丝袜美腿在线中文| 久久久久久久亚洲中文字幕| 日韩精品青青久久久久久| 在线观看美女被高潮喷水网站| 女的被弄到高潮叫床怎么办| av天堂中文字幕网| 日韩欧美三级三区| 亚洲成人久久爱视频| 久久久久久久久久成人| 九九久久精品国产亚洲av麻豆| 午夜福利视频1000在线观看| 日韩一区二区视频免费看| 最好的美女福利视频网| 99国产精品一区二区蜜桃av| 亚洲国产精品久久男人天堂| 日本-黄色视频高清免费观看| 亚洲av.av天堂| 一本久久中文字幕| 可以在线观看毛片的网站| av在线观看视频网站免费| 91久久精品国产一区二区成人| 中文字幕免费在线视频6| 日本黄色视频三级网站网址| 免费高清视频大片| 久久精品国产99精品国产亚洲性色| 在线a可以看的网站| 久久久久久国产a免费观看| 夜夜看夜夜爽夜夜摸| 精品午夜福利在线看| 桃色一区二区三区在线观看| 亚洲专区国产一区二区| 亚洲av成人av| 免费在线观看成人毛片| 免费看光身美女| 国产精品av视频在线免费观看| 美女cb高潮喷水在线观看| a级一级毛片免费在线观看| 美女免费视频网站| 18禁裸乳无遮挡免费网站照片| 免费人成在线观看视频色| 自拍偷自拍亚洲精品老妇| 69人妻影院| 国产av麻豆久久久久久久| 久久精品久久久久久噜噜老黄 | 欧美不卡视频在线免费观看| 国产私拍福利视频在线观看| 精品欧美国产一区二区三| 亚洲无线观看免费| 免费av毛片视频| 成人性生交大片免费视频hd| 久久精品国产亚洲av涩爱 | 久久精品国产亚洲av香蕉五月| 国内精品宾馆在线| 黄色欧美视频在线观看| 91午夜精品亚洲一区二区三区| 亚洲av一区综合| 久久精品国产亚洲av天美| 中文亚洲av片在线观看爽| 久久久精品94久久精品| 啦啦啦啦在线视频资源| 白带黄色成豆腐渣| 久久精品久久久久久噜噜老黄 | 日本成人三级电影网站| 国产成人福利小说| 99久国产av精品| 日本黄大片高清| 欧美一区二区亚洲| 免费黄网站久久成人精品| 色哟哟哟哟哟哟| 丰满乱子伦码专区| 老司机午夜福利在线观看视频| 亚洲欧美精品自产自拍| 九九热线精品视视频播放| 亚洲第一电影网av| 大型黄色视频在线免费观看| 日日摸夜夜添夜夜爱| 黄色欧美视频在线观看| 人人妻人人澡欧美一区二区| 日本一二三区视频观看| 国产大屁股一区二区在线视频| 此物有八面人人有两片| 天天躁日日操中文字幕| 亚洲欧美日韩高清在线视频| 精品人妻视频免费看| 性色avwww在线观看| 亚洲三级黄色毛片| 久久精品久久久久久噜噜老黄 | 国产精品一区二区性色av| 岛国在线免费视频观看| 观看免费一级毛片| 国产精品综合久久久久久久免费| 我要搜黄色片| 欧美国产日韩亚洲一区| 身体一侧抽搐| av视频在线观看入口| 人妻丰满熟妇av一区二区三区| 国产午夜精品久久久久久一区二区三区 | 我的女老师完整版在线观看| 午夜爱爱视频在线播放| 尾随美女入室| 婷婷六月久久综合丁香| 99热全是精品| 全区人妻精品视频| 中国国产av一级| 国产综合懂色| 精华霜和精华液先用哪个| 亚洲欧美清纯卡通| 欧美人与善性xxx| 国产高清视频在线观看网站| 蜜桃亚洲精品一区二区三区| 人妻夜夜爽99麻豆av| 免费搜索国产男女视频| a级一级毛片免费在线观看| 欧美bdsm另类| 最近的中文字幕免费完整| 亚洲精品一卡2卡三卡4卡5卡| 舔av片在线| 成人三级黄色视频| 亚洲av一区综合| 联通29元200g的流量卡| 日本 av在线| 99热6这里只有精品| 九九在线视频观看精品| 校园人妻丝袜中文字幕| 国产精品电影一区二区三区| 草草在线视频免费看| 欧美成人精品欧美一级黄| 日韩欧美 国产精品| 亚洲四区av| 人人妻人人澡人人爽人人夜夜 | 老熟妇仑乱视频hdxx| 两个人视频免费观看高清| 精品人妻一区二区三区麻豆 | 亚洲国产欧美人成| 高清毛片免费看| 22中文网久久字幕| 六月丁香七月| 国产亚洲精品av在线| 97超视频在线观看视频| 免费看日本二区| 1000部很黄的大片| 嫩草影院入口| 中国美白少妇内射xxxbb| 久久精品国产亚洲av香蕉五月| 少妇人妻精品综合一区二区 | 免费黄网站久久成人精品| 1000部很黄的大片| 深爱激情五月婷婷| 久久久a久久爽久久v久久| 午夜福利18| 精品一区二区三区视频在线| 国产白丝娇喘喷水9色精品| 国产一区二区激情短视频| 日本在线视频免费播放| 亚洲成人精品中文字幕电影| 国产美女午夜福利| 国产视频一区二区在线看| 偷拍熟女少妇极品色| 大又大粗又爽又黄少妇毛片口| 国产一区二区在线观看日韩| 最近的中文字幕免费完整| 亚洲中文字幕一区二区三区有码在线看| 丝袜美腿在线中文| 国产毛片a区久久久久| 一夜夜www| 在线播放无遮挡| 亚洲精品色激情综合| 欧美另类亚洲清纯唯美| 自拍偷自拍亚洲精品老妇| 日韩高清综合在线| 亚洲国产精品合色在线| 最近视频中文字幕2019在线8| 国产色婷婷99| 菩萨蛮人人尽说江南好唐韦庄 | 少妇熟女aⅴ在线视频| 久久精品综合一区二区三区| 国产在视频线在精品| 五月伊人婷婷丁香| 一级黄片播放器| 99视频精品全部免费 在线| 国产黄色小视频在线观看| 看黄色毛片网站| 国产av不卡久久| 国产成人a区在线观看| 少妇丰满av| 人妻久久中文字幕网| 亚洲国产精品sss在线观看| 可以在线观看的亚洲视频| 亚洲第一区二区三区不卡| 亚洲精品久久国产高清桃花| 色5月婷婷丁香| a级毛片a级免费在线| 日日摸夜夜添夜夜添小说| 亚洲18禁久久av| 99久久成人亚洲精品观看| 3wmmmm亚洲av在线观看| 日本黄色片子视频| 亚洲真实伦在线观看| 日本黄色片子视频| 男人舔奶头视频| 最近2019中文字幕mv第一页| 91久久精品电影网| 最近在线观看免费完整版| 国产极品精品免费视频能看的| 日韩欧美精品免费久久| 欧美区成人在线视频| 欧美zozozo另类| 国内精品一区二区在线观看| 精品免费久久久久久久清纯| 两性午夜刺激爽爽歪歪视频在线观看| 我要搜黄色片| 成人高潮视频无遮挡免费网站| 狠狠狠狠99中文字幕| 亚洲欧美日韩东京热| 我要搜黄色片| 成人永久免费在线观看视频| 九九热线精品视视频播放| 久久久久久久久中文| 九九热线精品视视频播放| 欧美潮喷喷水| 变态另类丝袜制服| 精品久久久噜噜| 国产一区亚洲一区在线观看| 老女人水多毛片| 亚洲av.av天堂| 国产aⅴ精品一区二区三区波| 一进一出好大好爽视频| 99久久成人亚洲精品观看| 男女做爰动态图高潮gif福利片| 精品久久久久久成人av| 日本 av在线| 直男gayav资源| 菩萨蛮人人尽说江南好唐韦庄 | 久久久久国产网址| 嫩草影院新地址| 不卡视频在线观看欧美| 嫩草影院新地址| 国产精品乱码一区二三区的特点| 欧美性猛交╳xxx乱大交人| 91在线观看av| av在线天堂中文字幕| 国产精品99久久久久久久久| 日韩成人av中文字幕在线观看 | 欧美精品国产亚洲| 亚洲三级黄色毛片| 精品久久久久久久久av| 大又大粗又爽又黄少妇毛片口| 日韩三级伦理在线观看| 国产精品久久电影中文字幕| 最新中文字幕久久久久| 亚洲av电影不卡..在线观看| 精品久久久久久久久亚洲| 欧美成人免费av一区二区三区| 国产蜜桃级精品一区二区三区| 级片在线观看| 亚洲18禁久久av| 可以在线观看毛片的网站| 91麻豆精品激情在线观看国产| 国产av一区在线观看免费| 日韩欧美一区二区三区在线观看| 欧美高清性xxxxhd video| 亚洲欧美成人综合另类久久久 | 色噜噜av男人的天堂激情| 欧美高清性xxxxhd video| 国产成人91sexporn| 亚洲人成网站高清观看| 国产精品国产三级国产av玫瑰| 老女人水多毛片| 国产亚洲91精品色在线| 99久久精品一区二区三区| 久久精品综合一区二区三区| 亚洲无线观看免费| 狠狠狠狠99中文字幕|