-
摘要: 采用高温固相法成功制备了Li2x−ySr1−xTi1−yNbyO3 (x=3y/4, y=0.25, 0.5, 0.6, 0.7, 0.75, 0.8)锂离子固体电解质，并通过X射线衍射（XRD）、扫描电子显微镜（SEM）、交流阻抗图谱、恒电位极化等分别研究了各个组分的晶体结构、微观形貌、离子电导率和电子电导率。XRD显示当y≤0.70时，材料为立方钙钛矿型结构，几乎没有杂质相生成。SEM表明随着掺杂含量的增加材料的晶粒尺寸逐渐增大。Li0.35Sr0.475Ti0.3Nb0.7O3锂离子固体电解质有着高离子电导率，为3.62×10−5 S·cm−1，其电子电导率为2.55×10−9 S·cm−1，活化能仅为0.29 eV。使用以Li0.35Sr0.475Ti0.3Nb0.7O3为隔膜的LiFePO4/Li半电池经过100圈循环后，放电比容量仍有93.9 mA·h·g−1，容量保持率为90.72%。Abstract: All-solid-state lithium batteries are recognized as the next-generation energy storage batteries due to their high energy density and high security, to which researchers have paid more attention. All-solid-state lithium batteries are composed of solid materials, and the Li-ion solid electrolytes do not contain flammable and explosive organic solvents, which can enhance the safety of the battery. As important components, Li-ion solid electrolytes are widely studied in all-solid-state lithium batteries, which currently include Li-superionic solid electrolyte (LISICON), Na-superionic solid electrolyte (NASICON), garnet-type solid electrolyte, perovskite-type solid electrolyte, sulfide-type solid electrolyte, and polymer solid electrolyte. Li-ion solid electrolytes generally have the advantages of high Li-ion conductivity, low electronic conductivity, wide operating temperatures, wide electrochemical windows, and inhibition of lithium dendrite growth. Among the solid electrolytes, the perovskite-type solid electrolytes have a wide tolerance factor that allows most elements to dope into the ABO3 structure. Additionally, the perovskite-type Li-ion solid electrolytes are summarized into two types: (1) the three-component Li3xLa2/3−xTiO3 (LLTO, 0 < x < 1/6) and (2) the four-component (Li, Sr)(A, B)O3 (A = Zr, Hf, Ti, Sn; B = Nb, Ta). In this paper, the four-component Li2x−ySr1−xTi1−yNbyO3 (x = 3y/4, y = 0.25, 0.5, 0.6, 0.7, 0.75, 0.8) solid electrolytes were prepared by conventional solid-state reaction method. X-ray diffraction (XRD), scanning electron microscopy, alternating current impedance, and potentiostatic polarization methods were adopted to study the crystal structure, micromorphology, ion conductivity, and electronic conductivity, respectively. XRD analysis show the synthesized samples exhibit a cubic perovskite structure when y≤0.70 with almost no impurity phase formed. Li0.35Sr0.475Ti0.3Nb0.7O3 exhibits the highest ion conductivity of 3.62×10−5 S·cm−1, electronic conductivity of 2.55×10−9 S·cm−1 at 20 ℃, and activation energy of only 0.29 eV. The LiFePO4/Li half-cell was fabricated using Li0.35Sr0.475Ti0.3Nb0.7O3 as a separator, exhibiting a capacity of 93.9 mA·h·g−1 and a retention capacity of 90.72% after 100 cycles.
-
Key words:
- perovskite /
- Li-ion solid electrolyte /
- AC impedance /
- electronic conductivity /
- lithium battery
-
图 2 Li2x−ySr1−xTi1−yNbyO3 (x=3y/4, y=0.25, 0.5, 0.6, 0.7)的拟合XRD图谱
Figure 2. Fitted XRD patterns of Li2x−ySr1−xTi1−yNbyO3 (x = 3y/4, y = 0.25, 0.5, 0.6, 0.7)
图 4 Li2x−ySr1−xTi1−yNbyO3样品的XPS总谱图（a）及Sr 3d（b）、Ti 2p（c）、Nb 3d（d）的区域XPS谱图
Figure 4. XPS spectra of Li2x−ySr1−xTi1−yNbyO3 samples (a), regions XPS spectra of Sr 3d (b), Ti 2p (c), Nb 3d (d)
图 5 20 ℃时Li2x−ySr1−xTi1−yNbyO3固体电解质的交流阻抗图谱
Figure 5. AC Impedance spectra of Li2x−ySr1−xTi1−yNbyO3 solid electrolytes at 20 ℃
图 6 Li2x−ySr1−xTi1−yNbyO3固体电解质的Arrhenius曲线
Figure 6. Arrhenius curves of Li2x−ySr1−xTi1−yNbyO3 solid electrolytes
图 7 Li2x−ySr1−xTi1−yNbyO3固体电解质的恒电位极化曲线
Figure 7. Li2x−ySr1−xTi1−yNbyO3 solid electrolytes constant potential polarization curves
图 8 以Li0.35Sr0.475Ti0.3Nb0.7O3为隔膜LiFePO4/Li半电池的充放电曲线图（a），放电比容量与库伦效率曲线图（b），电池的阻抗图谱（c）
Figure 8. Charge-discharge curves (a), discharge capacity and coulombic efficiency curves (b), AC impedance plot (c) of LiFePO4/Li half-cell with Li0.35Sr0.475Ti0.3Nb0.7O3 as the separator
表 1 Li2x−ySr1−xTi1−yNbyO3 (x=3y/4, y=0.25, 0.5, 0.6, 0.7)的晶胞精修数据
Table 1. Crystal refinement data of Li2x−ySr1−xTi1−yNbyO3 (x = 3y/4, y = 0.25, 0.5, 0.6, 0.7)
Sample Lattice
constant/
nmUnweighted-
profile R
factor /%Weighted
profile R
factor/%Goodness
of fitLi0.125Sr0.8125Ti0.75Nb0.25O3 0.39163 7.351 9.748 7.634 Li0.25Sr0.625Ti0.5Nb0.5O3 0.39315 6.291 8.229 3.709 Li0.3Sr0.55Ti0.4Nb0.6O3 0.39371 6.540 8.963 10.897 Li0.35Sr0.475Ti0.3Nb0.7O3 0.39422 6.354 8.648 9.334 
下载: 导出CSV
-
参考文献
[1] Takada K. Progress and prospective of solid-state lithium batteries. Acta Mater, 2013, 61(3): 759 doi: 10.1016/j.actamat.2012.10.034 [2] Sun C W, Liu J, Gong Y D, et al. Recent advances in all-solid-state rechargeable lithium batteries. Nano Energy, 2017, 33: 363 doi: 10.1016/j.nanoen.2017.01.028 [3] Zheng F, Kotobuki M, Song S F, et al. Review on solid electrolytes for all-solid-state lithium-ion batteries. J Power Sources, 2018, 389: 198 doi: 10.1016/j.jpowsour.2018.04.022 [4] Wang C H, Yang Y F, Liu X J, et. al. Suppression of lithium dendrite formation by using LAGP-PEO (LiTFSI) composite solid electrolyte and lithium metal anode modified by PEO (LiTFSI) in all-solid-state lithium batteries. ACS Appl Mater Inter, 2017, 9: 13694 doi: 10.1021/acsami.7b00336 [5] Adnan S B R S, Salleh F M, Mohamed N S. Effect of interstitial Li+ ion and vacant site Li+ ion on the properties of novel Li2.05ZnAl0.05Si0.95O4 and Li1.95Zn0.95Cr0.05SiO4 ceramic electrolytes. Ceram Int, 2016, 42(15): 17941 doi: 10.1016/j.ceramint.2016.08.047 [6] Hallopeau L, Bregiroux D, Rousse G, et al. Microwave-assisted reactive sintering and lithium ion conductivity of Li1.3Al0.3Ti1.7(PO4)3 solid electrolyte. J Power Sources, 2018, 378: 48 doi: 10.1016/j.jpowsour.2017.12.021 [7] Kokal I, Ramanujachary K V, Notten P H L, et al. Sol-gel synthesis and lithium ion conduction properties of garnet-type Li6BaLa2Ta2O12. Mater Res Bull, 2012, 47(8): 1932 doi: 10.1016/j.materresbull.2012.04.032 [8] Belous A G. Lithium ion conductors based on the perovskite La23−xLi3xTiO3. J Eur Ceram Soc, 2001, 21(10-11): 1797 doi: 10.1016/S0955-2219(01)00118-2 [9] Chen C H, Amine K. Ionic conductivity, lithium insertion and extraction of lanthanum lithium titanate. Solid State Ionics, 2001, 144(1-2): 51 doi: 10.1016/S0167-2738(01)00884-0 [10] Mitsuishi K, Ohnishi T, Tanaka Y, et al. Nazca Lines by La ordering in La2/3–xLi3xTiO3 ion-conductive perovskite. Appl Phys Lett, 2012, 101(7): 073903 doi: 10.1063/1.4744886 [11] Yu R, Du Q X, Zou B K, et al. Synthesis and characterization of perovskite-type (Li, Sr)(Zr, Nb)O3 quaternary solid electrolyte for all-solid-state batteries. J Power Sources, 2016, 306: 623 doi: 10.1016/j.jpowsour.2015.12.065 [12] Chen C H, Xie S, Sperling E, et al. Stable lithium-ion conducting perovskite lithium-strontium-tantalum-zirconium-oxide system. Solid State Ionics, 2004, 167(3-4): 263 doi: 10.1016/j.ssi.2004.01.008 [13] Kong Y Z, Li Y, Lu J Y, et al. Conductivity and electrochemical stability of perovskite-structured lithium-strontium-niobium-hafnium-oxide solid Li-ion conductors. J Mater Sci:Mater Electron, 2017, 28(12): 8621 doi: 10.1007/s10854-017-6586-2 [14] Huang B, Xu B Y, Li Y T, et al. Li-ion conduction and stability of perovskite Li3/8Sr7/16Hf1/4Ta3/4O3. ACS Appl Mater Interfaces, 2016, 8(23): 14552 doi: 10.1021/acsami.6b03070 [15] Kong Y Z, Li Y, Li J W, et al. Li ion conduction of perovskite Li0.375Sr0.4375Ti0.25Ta0.75O3 and related compounds. Ceram Int, 2018, 44(4): 3947 doi: 10.1016/j.ceramint.2017.11.186 [16] Kong Y Z, Li Y, Lu J Y, et al. Effect of doping (Al, La, Sm) on the conductivity of Li0.375Sr0.4375Hf0.25Ta0.75O3 ceramics. Mater Res Express, 2017, 4(9): 095504 doi: 10.1088/2053-1591/aa8ba7 [17] Lu J Y, Li Y. Conductivity and stability of Li3/8Sr7/16−3x/2LaxZr1/4Ta3/4O3 superionic solid electrolytes. Electrochimica Acta, 2018, 282: 409 doi: 10.1016/j.electacta.2018.06.085 [18] Mo S S, Lu P H, Ding F, et al. High-temperature performance of all-solid-state battery assembled with 95(0.7Li2S-0.3P2S5)-5Li3PO4 glass electrolyte. Solid State Ionics, 2016, 296: 37 doi: 10.1016/j.ssi.2016.09.002 [19] Cheng S, Smith D M, Li C Y. Anisotropic ion transport in a poly(ethylene oxide)-LiClO4 solid state electrolyte templated by graphene oxide. Macromolecules, 2015, 48(13): 4503 doi: 10.1021/acs.macromol.5b00972 [20] Lu D L, Ma J M, Wu J L, et al. Preparation and electrochemical properties of Li0.33SrxLa0.56−2/3xTiO3− based solid-state ionic supercapacitor. Ceram Int, 2019, 45(2): 2584 doi: 10.1016/j.ceramint.2018.10.192 [21] Sotomayor M E, Várez A, Bucheli W, et al. Structural characterisation and Li conductivity of Li1/2−xSr2xLa1/2−xTiO3 (0< x< 0.5) perovskites. Ceram Int, 2013, 39(8): 9619 doi: 10.1016/j.ceramint.2013.05.083 [22] Teranishi T, Kouchi A, Hayashi H, et al. Dependence of the conductivity of polycrystalline Li0.33BaxLa0.56-2/3xTiO3 on Ba loading. Solid State Ionics, 2014, 263: 33 doi: 10.1016/j.ssi.2014.05.001 [23] Wei Q, Cui W, Long X, et al. A investigation on the surface state of La1−xMx CoO3(M-Ca, Sr) perovskite oxides by XPS. Chem Res Chin Univ, 1990, 11(11): 1227 doi: 10.3321/j.issn:0251-0790.1990.11.013魏诠, 崔巍, 龙骧, 等. La(1−x)MxCoO3(M=Ca, Sr)表面状态的XPS研究. 高等学校化学学报, 1990, 11(11):1227 doi: 10.3321/j.issn:0251-0790.1990.11.013 [24] Yu K, Jin L, Li Y, et al. Structure and conductivity of perovskite Li0.355La0.35Sr0.3Ti0.995M0.005O3 (M = Al, Co and In) ceramics. Ceram Int, 2019, 45(18): 23941 doi: 10.1016/j.ceramint.2019.08.012 [25] Ofoegbuna T, Darapaneni P, Sahu S, et al. Stabilizing the B-site oxidation state in ABO3 perovskite nanoparticles. Nanoscale, 2019, 11(30): 14303 doi: 10.1039/C9NR04155A -
点击查看大图
计量
- 文章访问数: 98
- HTML全文浏览量: 26
- PDF下载量: 28
- 被引次数: 0
