Microporous polyurethane/acrylate gel polymer electrolyte obtained by emulsion polymerization

A novel polyurethane/acrylate (PUA) porous gel electrolyte was prepared by a new method, emulsion polymerization. Compared with the traditional phase inversion method, the new method can eliminate the pollution from solvent and decrease the cost of production. The swelling properties and morphology of the porous polymer membranes were characterized. The porous membranes, made by emulsion polymerization, could absorb large quantities of electrolyte solution to form porous gel electrolytes. The gel electrolytes have good solvent retention ability and high ionic conductivity. Copyright © 2004 Society of Chemical Industry     

增塑型锂离子电池聚合物电解质

从组成聚合物电解质的聚合物基材和电解液两方面进行分析,介绍了最近几年凝胶型、微孔型和复合型聚合物电解质的研究现状,比较了它们的制备方法、性能和特点,探讨了锂盐、增塑剂、离子液体和单离子导体等对聚合物电解质性能的影响,并简要评述了聚合物锂离子电池未来发展的前景趋势。     

荧光聚氨酯固态锂电池电解质的制备及性能

以聚碳酸酯二元醇(PCDL)和六亚甲基二异氰酸酯(HDI)为主要原料,1,4-丁二醇(BDO)和荧光小分子二元醇N,N-二羟乙基苯胺-β-三联吡啶(TPPDA)为扩链剂,制备了一种热塑性荧光聚氨酯,其与双三氟甲烷磺酰亚胺锂(LiTFSI)共混制备了荧光聚氨酯电解质(FPU)。采用傅里叶变换红外光谱仪、荧光光谱仪、拉伸测试仪、同步热分析仪、电化学工作站和电池测试仪对制备的电解质进行了结构、光学性能、力学性能、热稳定性能和电化学性能的测试与分析。结果表明,随着膜内LiTFSI质量分数的增加,荧光强度增大;LiTFSI质量分数为30%制备的荧光聚氨酯电解质膜(FPU-3)拉伸强度达到4.5 MPa,电导率达到1.03×10~(–4) S/cm;采用LiTFSI质量分数为30%的荧光聚氨酯电解质膜与磷酸铁锂正极和锂金属负极组装的全固态电池表现出良好的倍率与循环性能,在80℃、0.2 C和1.0 C倍率下首次放电比容量分别达到164和112 mA·h/g。     

凝胶聚合物电解质的电化学性能

用化学交联法制备了凝胶聚合物电解质.聚烯烃多孔膜支撑的凝胶聚合物电解质具有优良的电化学性能, 室温电导率为1.01×10^-3S•cm^-1,锂离子迁移数为0.41,在Al电极上的氧化起始电位达到4.2 V以上.采用聚烯烃多孔膜支撑的凝胶聚合物电解质制备了聚合物锂离子电池,并研究了工艺条件对聚合物锂离子电池电化学性能的影响.研究的工艺条件包括：单体添加量和电极组合方式.优化后的聚合物锂离子电池具有良好的电化学性能,1 C放电容量为0.2 C放电容量的93.2%,经100次1 C循环后的剩余容量仍在80%以上.     

Fabrication and properties of crosslinked poly(propylene carbonate maleate) gel polymer electrolyte for lithium‐ion battery

The poly(propylene carbonate maleate) (PPCMA) was synthesized by the terpolymerization of carbon dioxide, propylene oxide, and maleic anhydride. The PPCMA polymer can be readily crosslinked using dicumyl peroxide (DCP) as crosslinking agent and then actived by absorbing liquid electrolyte to fabricate a novel PPCMA gel polymer electrolyte for lithium‐ion battery. The thermal performance, electrolyte uptake, swelling ratio, ionic conductivity, and lithium ion transference number of the crosslinked PPCMA were then investigated. The results show that the T_g and the thermal stability increase, but the absorbing and swelling rates decrease with increasing DCP amount. The ionic conductivity of the PPCMA gel polymer electrolyte firstly increases and then decreases with increasing DCP ratio. The ionic conductivity of the PPCMA gel polymer electrolyte with 1.2 wt % of DCP reaches the maximum value of 8.43 × 10⁻³ S cm⁻¹ at room temperature and 1.42 × 10⁻² S cm⁻¹ at 50°C. The lithium ion transference number of PPCMA gel polymer electrolyte is 0.42. The charge/discharge tests of the Li/PPCMA GPE/LiNi_1/3Co_1/3Mn_1/3O₂ cell were evaluated at a current rate of 0.1C and in voltage range of 2.8–4.2 V at room temperature. The results show that the initial discharge capacity of Li/PPCMA GPE/LiNi_1/3Co_1/3Mn_1/3 O₂ cell is 115.3 mAh g⁻¹. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Electrical performance of lithium ion based polymer electrolyte with polyethylene glycol and polyvinyl alcohol network

A solid polymer electrolyte based on lithium hydroxide (LiOH) added with polyethylene glycol and polyvinyl alcohol polymers was synthesized by solution casting. The structural variation with respect to loading wt% of LiOH reveals the semicrystalline property of polymer electrolyte. The differential scanning calorimetry data shows the onset of crystalline to amorphous transition, which occurs nearly to the melting peak, for higher salt content. The structural properties and cross-linking between polymer and salt were demonstrated by polarized optical microscopy. The polymer electrolytes were subjected to AC impedance analysis spectra for obtaining the ionic conductivity at different temperature. The charge carriers relax much faster for higher lithium salt concentration based polymer electrolyte and produces higher conductivity. The highest room temperature conductivity 2.63 × 10^?5 S/cm is obtained for 8 wt% loading of lithium salt based polymer electrolyte, confirming their use in preparation of ion conducting devices.     

Structure and properties of an organic rectorite/poly(methyl methacrylate) nanocomposite gel polymer electrolyte by in situ synthesis

The synthesis of organic‐modified rectorite (OREC)/polymethyl methacrylate (PMMA) nanocomposite gel polymer electrolyte (NGPE) via in situ polymerization was investigated using free radical initiator in an solution, in which organic plasticizer, propylene carbonate(PC) acted as a solvent. A serious of NGPE membranes with different OREC content were prepared and characterized. The dispersion and exfoliation statuses of the OREC in the prepared NGPE membranes were analyzed through X‐ray diffraction (XRD) and transmission electron microscope (TEM), and the results indicated that for the NGPE with 5 wt % OREC membrane, OREC was partly exfoliated and well dispersed in the gel polymer electrolyte system. The electrochemical properties of the NGPE were determined by alternating current (AC) impedance spectroscopy, which illustrated that the ionic conductivity of the nanocomposite gel polymer electrolyte firstly increased and then decreased with increasing OREC content. Meanwhile, the maximum value of ionic conductivity for nanocomposite gel polymer electrolytes was obtained when organic clay amount was 5 wt %. The interactions among the components of the NGPE were investigated by Fourier transform infrared (FTIR) spectroscopy. It was shown that there were specific interactions between OREC and the other components, which may influence the conductivity and the stability of GPEs. Finally, an thermal stability enhancement was presented by NGPE with 5 wt % OREC compared with GPE, which was determined by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

A study on polyurethane/acrylate crosslinked gel polymer electrolytes

2,4‐Toluene diisocyanate, poly(propylene glycol), poly(ethylene glycol) (PEG) and 2‐hydroxyethyl methacrylate were used to synthesize PEG–UA (urethane acrylate) monomer. The crosslinked polymer and gel polymer electrolytes were prepared in dioxane by free radical polymerization. The swelling behaviour, thermal degradation properties, morphology and ionic conductivity of the gel polymer electrolytes were investigated. With decrease in the proportion of dioxane used, the synthesized polymer's network density increased, its affinity with a solution of 1 M LiClO₄ in propylene carbonate (PC) decreased, and more microgel which diffused in the network. At the same time, the conductivity increased and reached 4 × 10^?4 S cm^?1 at 25 °C. Copyright © 2003 Society of Chemical Industry     

Fabrication and characterization of PEO/PPC polymer electrolyte for lithium‐ion battery

A new poly(propylene carbonate)/poly(ethylene oxide) (PEO/PPC) polymer electrolytes (PEs) have been developed by solution‐casting technique using biodegradable PPC and PEO. The morphology, structure, and thermal properties of the PEO/PPC polymer electrolytes were investigated by scanning electron microscopy, X‐ray diffraction, and differential scanning calorimetry methods. The ionic conductivity and the electrochemical stability window of the PEO/PPC polymer electrolytes were also measured. The results showed that the T_g and the crystallinity of PEO decrease, and consequently, the ionic conductivity increases because of the addition of amorphous PPC. The PEO/50%PPC/10%LiClO₄ polymer electrolyte possesses good properties such as 6.83 × 10^?5 S cm^?1 of ionic conductivity at room temperature and 4.5 V of the electrochemical stability window. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

阻燃聚氨酯基固态聚合物电解的制备

摘要：以聚己二酸-1,4-丁二醇酯二醇( PBA) 、六亚甲基二异氰酸酯( HDI)和阻燃剂N，N阻双（2（羟乙基）胺基亚甲基磷酸二乙酯( FCR-6）为主要原料合成阻燃聚氨酯（TPUP），将阻燃聚氨酯与锂盐复合得到阻燃聚氨酯基固态聚合物电解质。采用红外光谱、热重分析、锥形量热、力学测试、电化学窗口、电导率和电池的充放电性能测试等对阻燃聚氨酯基固态聚合物电解质进行了表征和性能测试。研究表明，TPUP具有良好阻燃性能，制备的阻燃电解质TPUP25%Li综合性能最佳，且拉伸强度达到2.09MPa，80℃时离子电导率为3.09M10-4 S/cm，以阻燃电解质组装的全固态锂电池，在80℃时0.2C电流密度下放电容量达到159mA?h/g。     

Mechanically robust and highly electrochemical performance of polyethylene oxide gel polymer electrolyte

Synthesizing high-performance of gel polymer electrolytes (GPEs) with simple methods and common materials has long been a crucial concern for lithium-ion batteries. Here, the poor mechanical properties of polyethylene oxide (PEO) based GPEs were overcome by introducing strong hydrogen bond between PEO and polyacrylic acid (PAA). Easy-available PEO/PAA membranes were prepared though hot processing approach without use of organic solvent during all processes. The mechanical properties and crystalline of dry composites could be tuned by the addition content of PAA. After quick absorbing electrolyte in 30 min, the tensile strength and elongation at break of the GPEs composites are ranged from 0.07 to 0.63 MPa, and 525% to 722%. Moreover, the lithium-ion conductivity and transference number with 30 wt% addition of PAA reach up to 1.66 and 0.58 mS/cm, respectively. After 500 cycling at 0.5 C, the discharge specific capacity and the capacity retention rate are still up to 134.1 mAh/g and 88.7%, respectively. This research proves the great possibility of applying environmentally friendly method, low cost, and high electrochemical performances of PEO/PAA based GPEs in the lithium batteries.     

Cellulose triacetate‐based polymer gel electrolytes

New composite polymer gels were obtained from cellulose triacetate (CTA), N‐methyl‐N′‐propylpyrrolidinium bis(trifluoromethanesulfonyl)imide (Pyr_1,3TFSI), and lithium bis(trifluoromethanesulfonyl)imide (LiTFSI). Analysis by differential scanning calorimeter and scanning electron microscope showed that the ionic gel consisting of CTA, Pyr_1,3TFSI, and LiTFSI formed a completely homogeneous phase at the molar ratio of CTA/Pyr_1,3TFSI/LiTFSI = 1/3/1.5. The ionic conductivity of the polymer gel was significantly enhanced by the presence of LiTFSI. FTIR study strongly implies that the interaction of lithium ion with the carbonyl group of CTA could be responsible for the increase in conductivity. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

苯酐改性聚乙二醇型聚氨酯固态电解质的制备与性能

以异佛尔酮二异氰酸酯（IPDI）、聚对苯二甲酸-3-甲基-1,5-戊二醇酯二醇（TPA-1000）、聚乙二醇（PEG-2000）、一缩二乙二醇（DEG）为主要原料合成了一系列热塑型聚氨酯弹性体,然后加入20%的锂盐（LiTFSI）制备不同的全固态电解质（SPE）。结果表明,随着TPA-1000含量的减少和PEG-2000含量的增加,SPE的耐热性增加,玻璃化转变温度减小,拉伸强度减小,断裂伸长率增加。SPE的离子电导率与温度的关系基本符合Arrhenius方程,在80℃,SPE（除纯PEG-2000的电解质外）的电化学窗口均达到4.0V以上,其中质量比TPA-1000：PEG-2000=1：2（SPE4）综合性能最佳,力学为1.87Mpa、电导率为2.15?10-4 S cm-1、窗口为4.3V。以SPE4组装的全固态电池在80℃、0.2C下放电比容量为150 mAh/g。     

Semi-interpenetrating gel polymer electrolyte based on PVDF-HFP for lithium ion batteries

Poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP)-based gel polymer electrolyte (GPE) is considered one of the promising candidate electrolytes in the polymer lithium ion battery (LIB) because of its free standing, shape versatility, security, flexibility, lightweight, reliability, and so on. However, the pristine PVDF-HFP GPE cannot still meet the requirement of large-scale LIBs and other electrochemical devices due to its relatively low ionic conductivity and deterioration of mechanical strength caused by the incorporation of organic liquid electrolyte into the polymer matrix as well as high cost. In order to overcome above deficiencies of PVDF-HFP based GPE, ultraviolet (UV)-curable semi-interpenetrating polymer network is designed and synthesized through UV-irradiation technique, and the as-prepared semi-interpenetrating matrix is constituted by pentaerythritol tetracrylate polymer network and PVDF-HFP. The ionic conductivity of the optimized GPE is as high as 5 × 10⁻⁴ S/cm and electrochemical window is up to 4.8 V at room temperature. Especially, the LIB prepared by GPE shows the high initial discharge specific capacity of 151 mAh/g at 0.5 C and good rate capability. Therefore, the semi-interpenetrating GPE based on PVDF-HFP exhibits a promising prospect for the application of rechargeable LIBs.     

凝胶聚合物电解质在锂硫电池中的应用状况

从凝胶聚合物电解质的制备方法 (原位聚合法和溶液浇铸法)出发,对锂硫电池中凝胶聚合物电解质的应用展开了探究。     

Application of liquid gel polymer electrolyte based on chitosan–NH4NO3 for proton batteries

Liquid gel polymer electrolyte (LGPE) based on chitosan, ammonium nitrate, and acetic acid with a ratio of 1.9 : 0.17 : 96.3 wt % gives the highest conductivity of (1.46 ± 0.07) ´ 10⁻¹ S cm⁻¹ at room temperature. This optimized composition of electrolyte is then used in proton batteries with the configuration of Zn + ZnSO₄·H₂O/LGPE/MnO₂. The open circuit voltage of battery is 1.41 V during 48 h of storage. The battery obtained a discharge capacity of 27.90 mA h⁻¹ upon discharge at 1.0 mA current. The maximum power density for the battery is 3.67 mW cm⁻². © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

高锂盐含量聚氨酯基固态电解质的制备与性能

以异佛尔酮二异氰酸酯、聚碳酸酯二元醇和一缩二乙二醇为原料,合成硬段质量分数为30%的聚碳酸酯型聚氨酯(PCPU),将合成的聚氨酯和双三氟甲烷磺酰亚胺锂(LiTFSI)复合制得不同锂盐质量分数的固态聚合物电解质(SPE)。通过红外光谱分析了聚氨酯结构,采用TG、DSC测试了聚氨酯及电解质的热学性能,并采用交流阻抗、线性扫描伏安测试探究了不同LiTFSI质量分数对电解质电化学性能的影响。结果表明,随着LiTFSI质量分数的增加,聚氨酯基固态聚合物电解质的室温离子电导率呈现先增大后减小再增大的趋势,当锂盐质量分数为70%时,制备的电解质离子电导率达到最大值(1.28×10~(–8)S/cm),以此固态电解质与LiFePO4正极组装的固态电池在60℃、0.2 C电流密度时放电比容量为153 mA·h/g,循环100次容量保持率为84%。     

柔性聚合物电解质的制备及其电化学性能

以不同质量比的丙烯酸甲酯(MA)和丙烯腈(AN)为单体,聚乙烯醇(PVA)为分散剂,采用绿色环保的改性乳液聚合法制得聚合物乳液,将聚合物乳液流延涂布制得柔性聚合物膜,进一步采用电解液浸润法制得系列柔性聚合物电解质膜(S1、S2、S3和S4)。通过傅里叶红外光谱仪(FTIR)、扫描电镜(SEM)、力学性能测定、热分析、交流阻抗(EIS)和充放电测试对材料的物理化学性能进行了表征。结果表明:当m(MA)∶m(AN)=23∶2(S2)时,聚合物膜的抗拉强度为14.3 MPa,断裂伸长率为248%,25℃时的离子电导率为0.95m S/cm。分别以LiCoO_2为正极、金属锂为负极,天然石墨为正极、金属锂为负极制备CR2032扣式锂离子电池并测试其循环伏安性能和充放电性能,4次循环伏安测试发现峰电位均无明显变化,0.1 C倍率下,首次放电比容量分别为142和307 mA·h/g,50次循环后分别为135和323 m A·h/g,1.0 C倍率下,LiCoO_2的放电比容量为134.3 mA·h/g,说明所制备的材料具有较好的电化学性能。     

磷酸铁锂正极材料与电解液的相容性研究

在锂离子电池使用过程中磷酸铁锂正极材料会与电解液发生许多副反应,导致铁的溶解,造成正极材料与电解液相容性差。为了研究磷酸铁锂正极材料与电解液的相容性及其对电池搁置性能的影响,先利用电感耦合等离子发射光谱对不同磷酸铁锂正极材料在不同电解液中的溶铁量进行了表征,后又对制备的电池进行了常温及高温搁置性能测试。结果表明：磷酸铁锂正极材料对电解液具有选择性,并且正极材料在电解液中的溶铁量越大,其相容性越差,对锂离子电池性能影响越大。     

A novel polymer electrolyte based on polydioxolane polyurethane with Na+ single‐ionic conductivity

A series of novel polyurethane ionomers with polydioxolane (PDXL) as soft segment was prepared and characterized by Fourier transform infrared spectroscopy, differential scanning calorimetry, and dynamic mechanical analysis. The ionomers obtained were Na⁺ single‐ionic conductors. Their ionic conductivity and water absorption were tested. At medium temperature (> 75°C), the conductivity of ∼ 10⁻⁵ s cm⁻¹ was reached. The temperature dependence of conductivity could not be well expressed by both Arrhenius and VTF equations. When ionization level was fixed, the conductivity increased as the Mn of PDXL decreased. We also discussed the effect of ionization level on water absorption. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 71: 1711–1719, 1999