酞菁铁添加剂对AB_3型镍氢电池电化学性能影响

采用共沉淀还原扩散法制备了La0.67Mg0.33Ni2.5Co0.5合金。以固相法合成酞菁铁,研究了酞菁铁作为镍氢电池电解液添加剂和负极添加剂时对电池电化学性能的影响,结果表明,在电解液中,当酞菁铁添加量为0.045%时,电池的最大放电容量提高了20 mAh/g,容量衰减率降低了10.98%;在电池负极中,当酞菁铁添加量为1.0%时,电池的最大放电容量提高了40 mAh/g,容量衰减率降低了13.14%。     

锂离子电池的低温性能改善

研究了锂离子电池碳纳米管导电剂(CMTs)、电解液对锂离子电池-40℃低温放电性能的影响.以额定容量为2750mAh的INPP78/34/95锂离子电池为例,在40℃下,负极中添加了 CNTS的电池的放电电压平台比负极中添加SP的电池的放电电压平台提高0.17V,低温放电容量提高了7.5%.     

炭气凝胶的添加改善铅酸电池负极的性能

炭气凝胶是一种具有高比表面积和高导电性的多孔炭材料,本研究采用炭气凝胶作为负极添加剂来改善铅酸电池性能。实验添加的炭气凝胶的质量占铅粉质量的3%。在循环伏安测试中,加入炭气凝胶的铅酸电池负极的氧化和还原反应峰值电流增大。在恒电流放电测试中,根据理论值设定的放电倍率为1C时,加入炭气凝胶后的放电容量达到了190mAh·g~(-1),比不添加时提高了50%。1C充电时,加入炭气凝胶后的充电容量达到了230mAh·g~(-1),比不添加时提高了21%。在3C倍率下添加炭气凝胶的电池的放电和充电容量也都高于不添加的电池。结果证明炭气凝胶改善了铅酸电池负极充放电性能,提高了电池的库伦效率。     

微弧氧化三氧化钨负极材料制备及电化学性能研究

采用微弧氧化法,以钛箔作为基体,钨酸盐为电解液,成功制备出WO3/TiO2复合膜作为锂离子电池负极材料.利用扫描电子显微镜、X射线衍射仪对复合膜组织结构进行表征,复合膜主要由WO3和TiO2组成.当电解液中钨酸钠质量为70 g时,测得电池电化学性能最稳定,比容量为605.684 mAh/g,循环200圈后比容量保持在1...     

以偕胺肟基聚丙烯腈为粘结剂的锂离子电池负极的研究

粘结剂虽然在硅基锂离子电池中的占比虽然较少,但是在对电池的电化学性能起到重要的作用,本研究使用偕胺肟基聚丙烯腈为硅基锂离子电池的粘结剂,与聚丙烯腈(PAN)为粘结剂的锂离子电池硅基负极在电化学性能方面进行对比,利用扫描电镜(SEM)对偕胺肟基聚丙烯腈和聚丙烯腈的负极极片进行的表征。本研究以聚丙烯腈为原材料制备的偕胺肟基聚丙烯腈复合纳米硅以及导电炭为电池负极,以铜箔为集流体,隔膜为celgard2400,实验结果显示,采用偕胺肟基聚丙烯腈为粘结剂的硅基负极在电流密度为1000mA/g的情况下,首圈放电比容量达到了1496. 1mAh/g,经过了200圈的循环后,其放电比容量仍有434. 7mAh/g,而以聚丙烯腈为粘结剂的硅基负极在同样的条件下,首圈放电比容量有1411. 6mAh/g,经过了200圈的循环后,其放电比容量仅有57mAh/g。     

硅碳负极材料的合成研究

以光伏产业废硅粉为原料,采用球磨工艺, CMC为碳源,得到了最优的碳包覆比例,得到了一种碳包覆硅碳负极材料。借助扫描电镜(SEM)和模拟电池测试等方法,对硅碳复合材料的结构、形貌和电化学性能进行表征。结果表明,采用2.5%CMC添加量的碳包覆材料性能较优,其首次放电比容量为850.3 mAh/g,20次放电容量还保持690.8 mAh/g,为首次放电容量的81.24%mAh/g。     

石墨烯复合碳纳米管添加量对锂离子电池性能的影响

研究了石墨烯复合碳纳米管添加量对锂离子电池性能的影响.结果表明,随着石墨烯复合碳纳米管的加入,能有效的降低极片的膜片电阻率,当石墨烯复合碳纳米管增加到一定量(1.0wt％)时,电阻率变化减缓甚至不变.EIS结果表明,在0.5wt％SP添加量基础上,石墨烯复合碳纳米管的最优添加量为1.0wt％,能获得相对较低的电极阻抗.电性能表现上,0.5wt％SP和1.0wt％石墨烯复合碳纳米管(即GN:CNT=3:7)的导电剂配方的电池循环性能较为优异,在1C电流密度下放电比容量最高为138.2mAh/g,且在此基础上循环400周后,放电容量保持率为95.3％;该配方电池的倍率性能也相对较优,其5C放电比容量是0.5C的71.4％,该组导电剂配方有着相对较小的电池阻抗.     

铅酸蓄电池电解液添加剂的研究

研究了铅酸蓄电池电解液中加入添加剂对电池性能的影响。通过测定电池放电容量、充电接受能力、极化曲线及荷电保持能力 ,比较了在电解液中加入E、F两种添加剂和不加添加剂的电池性能。结果表明 :在电解液中加入E、F添加剂后 ,电池的充电接受能力尤其是低温充电接受能力得以大大改善 ,并提高了负极析氢过电位 ,从而降低了电池贮存过程中的自放电。     

水热法合成聚酰亚胺及其储镁性能研究

以1,4,5,8-萘四甲酸酐和对苯二胺为原料，使用水热法在200℃下反应5 h,制备了聚酰亚胺(PI);采用红外光谱法(FTIR)和X射线衍射法(XRD)对其结构进行了表征；同时，组装了以PI为负极、硫酸镁水溶液为电解液、活性炭为正极的电池体系，并测定了PI的储镁性能，充电时，镁离子与负极PI发生还原反应，硫酸根离子嵌入到正极活性炭颗粒中；放电过程相反。恒电流充放电测试表明，在50 mA/g的充放电电流下，PI在首次循环中的充电比容量为107.6 mAh/g,放电比容量为94.6 mAh/g,效率为87.91%;100次循环后，放电比容量降为66.2 mAh/g,库伦效率升高到97.65%。最后，采用循环伏安法CV、EIS对PI电化学性能进行测试，证明PI具有良好的储镁性能。     

硫酸钴对镍电极电化学性能的影响

研究了CoSO4添加剂对镍电极和镍氢电池电化学性能的影响，镍电极反应活性和可逆性随CoSO4添加量增加而增大，CoSO4经过3-5次充放电循环后逐渐转变为CoOOH，与CoO添加剂的变化趋势一致。采用含CoSO4的镍电极与金属氢化物电极组装成MH／Ni电池，在第150次循环之前，电池放电容量一直随着循环次数的增加而增加，经过250次循环后，容量保持率仍高达95％：CoSO4添加量分别为11.2％、18.7％和30.0％时，相应的镍电极最高放电比容量分别为270、280和287mAh／g。由于CoSO4具有制备工艺简单、不容易氧化、成本低等特点，因此可替代CoO降低MH／Ni电池的制造成本。     

Electrochemical properties of an ordered mesoporous carbon prepared by direct tri-constituent co-assembly

An ordered mesoporous carbon with a high surface area of 2390 m²/g and a large pore size of 6.7 nm was synthesized through an organic-inorganic-surfactant tri-constituent co-assembly method which used resols as the carbon precursor, silicate oligomers as the inorganic precursor and triblock copolymer as the soft template. The electrochemical properties of this carbon were evaluated as an electrode material for electrochemical double layer capacitor and lithium-ion battery. It shows rectangular-shaped cyclic voltammetry curves over a wide range of scan rates even up to 200 mV/s between 0 and 3 V, with a large capacitance of 112 F/g in nonaqueous electrolyte. As a negative electrode material for lithium-ion battery, it delivers a reversible specific capacity as high as 1048 mAh/g and a good cycling ability with capacity retention of 500 mAh/g over 50 cycles.     

稀土La(Ⅲ)掺杂非晶态氢氧化镍的电化学性能

采用微乳液快速冷冻沉淀法制备出稀土La(Ⅲ)掺杂非晶态Ni(OH)2粉体材料,对样品粉体的微结构及形态进行了表征分析,同时将样品作为活性物质合成电极材料,组装成碱性MH-Ni模拟电池,测试其电化学性能。结果表明,掺杂6%La(Ⅲ)样品材料微结构无序性强,质子缺陷较多。将所制备的样品在80 mA/g恒电流充电5.5 h,40 mA/g恒电流放电,终止电压为1.0 V的充放电制度下,其放电平台达到1.256 V,放电比容量为317.1 mAh/g,充放电循环30次放电比容量衰减仅为3.943%,具有较好的电化学稳定性和循环可逆性。     

TEM investigation of MnO2 cathode containing TiS2 and its influence in aqueous lithium secondary battery

The discharge characteristics of manganese dioxide (MnO₂) cathode in the presence of small amounts (1, 3 and 5 wt.%) of TiS₂ additive has been investigated in an alkaline cell using aqueous lithium hydroxide as the electrolyte. The incorporation of small amounts of TiS₂ additives into MnO₂ was found to improve the battery discharge capacity from 150 to 270 mAh/g. However, increasing the additive from 3 to 5 wt.% causes a decrease in the discharge capacity. Hence, the objective is to gain insight into the role of TiS₂ on the discharge characteristics of MnO₂ and its mechanism. For this purpose, we have used transmission electron microscopy (TEM) and electron energy loss spectroscopy (EELS) techniques.     

The effect of B4C addition to MnO2 in a cathode material for battery applications

Boron carbide (B₄C) added manganese dioxide (MnO₂) used as a cathode material for a Zn-MnO₂ battery using aqueous lithium hydroxide (LiOH) as the electrolyte is known to have higher discharge capacity but with a lower average discharge voltage than pure MnO₂ (additive free). The performance is reversed when using potassium hydroxide (KOH) as the electrolyte. Herein, the MnO₂ was mixed with 0, 5, 7 and 10 wt.% of boron carbide during the electrode preparation. The discharge performance of the Zn|LiOH|MnO₂ battery was improved by the addition of 5-7 wt.% boron carbide in MnO₂ cathode as compared with the pure MnO₂. However, increasing the additive to 10 wt.% causes a decrease in the discharge capacity. The performance of the Zn|KOH|MnO₂ battery was retarded by the boron carbide additive. Transmission electron microscopy (TEM), and energy dispersive X-ray spectroscopy analysis (EDS) results show evidence of crystalline MnO₂ particles during discharging in LiOH electrolyte, whereas, manganese oxide particles with different oxygen and manganese counts leading to mixture of phases is observed for KOH electrolyte which is in agreement with X-ray diffraction (XRD) data. The enhanced discharge capacity indicates that boron atoms promote lithium intercalation during the electrochemical process and improved the performance of the Zn|LiOH|MnO₂ battery. This observed improvement may be a consequence of B₄C suppressing the formation of undesirable Mn(III) phases, which in turn leads to enhanced lithium intercalation. Too much boron carbide hinders the charge carrier which inhibits the discharge capacity.     

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.     

Study of poly(organic palygorskite-methyl methacrylate)/poly(ethylene oxide) blended gel polymer electrolyte for lithium-ion batteries

In this study, the composite polymer was prepared by blending poly(ethylene oxide) (PEO) and POPM (the copolymer of methyl methacrylate [MMA] and organically modified palygorskite), and then the composite polymer based membrane was obtained by phase-inversion method. The scanning electron microscopy results showed that the composite polymer membrane has a three-dimensional network structure. X-ray diffraction results indicated that the crystalline region of PEO is disappeared when introduction of a certain amount of the PEO. Meanwhile, the elongation of composite polymer membrane increased when increasing PEO concentration, but the value of tensile strength of PEO-POPM membrane decreased. When the mass fraction of PEO was 24%, the porosity and maximum value of ionic conductivity of the composite polymer membrane were 54% and 2.41 mS/cm, respectively. The electrochemical stability window of Li/gel composite polymer electrolyte/stainless steel batteries was close to 5.3 V (vs. Li⁺/Li), and the battery of Li/gel composite polymer electrolyte/LiFePO₄ showed good cycling performance and the discharge capacity of the battery were between 169.8 and 155 mAh/g. Meanwhile, the Coulombic efficiency of the battery maintained over 95% during the 80 cycles.     

Electrolyte optimization for a Li ion battery by charge profile analysis

Electrolyte design for Li ion batteries was approached by means of comparison of faradaic and non-faradaic currents. The faradaic current by the movement of Li⁺ ions was dependent on the composition of the electrolyte and was related to the battery capacity; the higher the capacity, the greater the current by the faradaic reaction. The open circuit potential of the electrode with a greater faradaic current decreased at a slower rate than that of the electrode with a smaller faradaic current. This analysis method can be used to prepare an optimal electrolyte of an actual Li ion battery, especially when developing batteries with excellent high-rate discharge capabilities and low temperature discharge properties.