氧化锆纤维布的研究

氧化锆纤维布是大容量碱性电池的理想隔膜材料.本文研究了氧化锆纤维布的制备工艺,原料纤维、浸渍工艺参数、热处理工艺等对氧化锆纤维布性能的影响.所研制的氧化锆纤维布在大容量镍氢电池中作为隔膜得到了应用,电性能及吸碱速率和吸碱量优于美国产品,但强度低于美国产品.     

提高碱性锌锰电池大电流放电性能的方法

结合实际生产,在不改变碱性锌锰电池结构及其他性能(如中小电流放电性能、贮存性能及安全性能)的前提下,通过采用变薄优质的隔膜、真空吸液法增加电池内的电解液量、对正负极配方进行优化及正负极容量重新搭配等方法,生产出了大电流放电性能更优的碱性锌锰电池,同时,采用大电流放电和大电流用电器具实物测试等手段,对生产出的大电流放电性能更优的电池与未采用以上几种方法制得的电池进行比较,证明了采用以上几种方法可提高碱性锌锰电池大电流放电性能,达到了满足客户需求、提高市场占有率的目的。     

干法、湿法隔膜对动力型锂离子电池性能影响分析

湿法隔膜与干法隔膜对动力型锂离子电池的性能影响不同.在保证其透气度、孔隙率基本一致的前提下,对比使用湿法隔膜制备的电池与使用干法隔膜制备的电池性能.结果表明,湿法隔膜吸液能力较干法隔膜高80％;湿法隔膜25℃环境下倍率放电温升较干法隔膜2 C放电低约26.1％,3 C放电低约5.5％;湿法隔膜电池DCIR数据降低6.4...     

锂离子电池用隔膜孔隙率对电池性能的影响

考察了锂离子电池用隔膜孔隙率对锂离子电池内阻、倍率放电、高温储存、常温0.5 C/0.5 C循环等性能的影响。随着锂离子电池隔膜孔隙率的增加,电池内阻有所降低,高温储存性能有所下降;电池小电流(0.5 C、1 C)倍率放电性能影响不大,大电流(2 C、3 C)倍率放电性能有所提升;常温0.5 C/0.5 C循环性能有所提高。综合考虑,当锂离子电池隔膜孔隙率为42%时,电池性能较优。     

隔膜对锂硫电池性能的影响研究

本文测试了PP/PE/PP、PI和PPA三种不同种类隔膜的吸液性能,并研究了三种隔膜对锂硫电池电化学性能的影响,实验结果表明,隔膜吸液性能好坏排序为PP/PE/PPPIPPA,且电池的放电性能随着隔膜吸液性能的提升而有所提高。     

碱性电池隔膜用丙纶非织造布的等离子体改性

利用低温等离子体技术对碱性电池隔膜用丙纶非织造布进行表面改性处理,探讨了影响电池隔膜性能的因素,利用红外光谱、扫描电镜对材料表面性能进行了表征分析。结果表明,不同气体的等离子体对丙纶非织造布进行表面处理的最佳工作参数放电气体、放电功率、放电时间、工作压强分别为:氩气,70 W,3 min,15 Pa;氧气,120 W,3 min,30 Pa;空气,100 W,3 min,50 Pa。通过等离子体表面活化处理,在丙纶表面引入了亲水性基团,同时产生了刻蚀,丙纶非织造布的吸碱速率可提高至每10 min 8 cm左右,吸碱率提高至250%,面电阻大幅降低至8 Ω/cm2左右。     

高功率铅酸电池的保障——耐穿刺AGM隔膜

高功率铅酸电池具备短时大电流放电特性,主要应用于通信、电力、医院等领域。立足于高功率铅酸电池的工作原理及AGM隔膜在电池中的作用,通过添加有机纤维,研发出新型耐穿刺AGM隔膜,性能优越于普通隔膜,能够在高功率放电状态下正常工作,具有很好的市场前景。     

储氢合金粉表面包覆镍硼合金的研究

储氢合金是影响镍氢电池性能的主要因素,对储氢合金进行表面处理可以有效提高镍氢电池的性能。本文对储氢合金表面进行包覆镍硼合金处理,通过扫描电镜(SEM)及X射线衍射分析(XRD)对电极表面进行了表征,测定了包覆前后镍氢电池的大电流放电性能,以交流阻抗法和循环伏安法对电极进行了评价。结果表明,包覆镍硼合金后,电化学阻抗减小,电极的大电流放电性能有所提高,循环寿命增长,对储氢合金表面包覆镍硼合金可有效提高镍氢电池性能。     

氧化铝/丙烯酸酯乳液改性聚乙烯隔膜的制备及性能

以丙烯酸酯乳液作为粘结剂,水为分散介质,利用氧化铝颗粒对锂离子电池用聚乙烯(PE)隔膜进行了陶瓷改性,得到涂覆PE隔膜,并对其表面张力、接触角、浸润性、吸液率、热收缩及电化学性能进行了测定。结果表明:加入浆料质量0.10%的含氟表面活性剂后,浆料表面张力由37.0 mN/m降低至28.5 mN/m。涂覆PE隔膜对比PE隔膜,润湿性和耐热性能以及电化学性能均得到明显改善,吸液率由85%提高到165%,150℃的热收缩率从67.20%降至3.00%以内。200次循环,涂覆PE隔膜和PE隔膜的容量保持率分别为90.2%、84.7%,不同倍率下涂覆PE隔膜组装的电池,放电容量总是高于原PE隔膜组装的电池的放电容量,交流阻抗、伏安循环性能两者类似。     

金属氢化物-镍电池用隔膜的研究进展

评述了尼龙纤维、丙纶纤维和维纶纤维等氢镍电池用隔膜的性能.对这些聚合物进行改性处理,可以改善隔膜的亲水性和吸碱能力,从而提高隔膜的性能.具有OH-交换功能的聚合物隔膜可以将电解液完全吸附于其中,使电解液中的氢氧根只能在隔膜中自由移动,同时阻止电池正、负极金属离子向对方的迁移,从而有效降低电池自放电及延长电池循环寿命.指出聚合物隔膜将成为未来隔膜的研究重点,其中选择合适的骨架材料,探索合适的接枝条件,提高聚合物链段的运动能力是今后的研究方向.     

Polyphenols assisted silica coating on polypropylene separators with improved wettability and heat-resistance for lithium-ion batteries

The separator, as one of the essential components for lithium-ion batteries (LIBs), has garnered considerable attention because of its significant role in battery performance. Here, an in-situ coating method to promote the wettability and thermal-stability of polypropylene (PP) separators was reported. The separator was first dip-coated with phenolic compound based on biologically inspired surface modification. Then silica layers were in-situ formed on the separator via a sol–gel process of silicate solution, so that an inorganic–organic hybrid layer was coated on PP separators without the need of any polymer binders. Besides, this method hardly increases the film thickness or sacrifices microporous structure of the pristine separator. Due to the introduction of hybrid layers, the resulted separators showed excellent dimensional thermostability, as the thermal shrinkage was only 20% at 150 °C while that of the bare separator was about 80%. Meanwhile, electrochemical performances of cells with the modified separator were obviously improved, especially the rate performance. At the charge/discharge current density of 5 C, cells with PP separators nearly lost all the capacity, but the modified separator still held 45.7% of the discharge capacity at 0.2 C. This facile yet effective method has great application prospects in the preparation of ceramic-coated separators. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47277.     

聚丙烯腈/聚酯无纺布微孔复合锂电隔膜的制备及性能

为了改善锂电隔膜的耐热性、电解液亲和性和机械性能,本文以聚丙烯腈为主要材料,采用相转化法制备了聚酯无纺布支撑的聚丙烯腈微孔复合锂电隔膜,对隔膜的理化性能（孔道结构、机械性能、电解液性能和耐热性）和电池性能（循环性能、倍率性能）进行系统研究。结果表明,复合隔膜具有均匀的微孔结构,平均孔径约为425nm,孔隙率为74%,拉伸强度为30MPa;电解液亲和性良好,吸液率为385%,接触角接近0°,锂离子电导率较市售隔膜显著提高,达到1.65mS/cm;在150℃、0.5h的热处理条件下,复合隔膜的热收缩率为0。鉴于良好的理化特性,该隔膜所装配的钴酸锂/锂金属电池表现出优异的循环容量和倍率容量保持性,如在0.2C倍率下,经历200次循环后电池的放电容量保持率为95.2%,在10C倍率下电池的放电容量为0.5C倍率下的58.3%。因此,相转化法制备的聚丙烯腈基微孔复合隔膜在锂离子电池中显示出较好的应用前景。     

Electrochemical performance and thermal property of electrospun PPESK/PVDF/PPESK composite separator for lithium-ion battery

In this study, PPESK/PVDF/PPESK tri-layer composite separators for lithium-ion batteries were prepared by electrospinning technique. The physical properties, electrochemical performances and thermal properties of composite separators were investigated. Results indicate that PPESK/PVDF/PPESK separator displays good wettability in liquid electrolyte. The electrolyte uptake of PPESK/PVDF/PPESK separator is much higher than that of electrospun PVDF, which leads to higher ionic conductivity of PPESK/PVDF/PPESK separator than PVDF separator. Discharge capacity of the cell assembled with PPESK/PVDF/PPESK separator is increased by 50 % than that with PVDF separator. Initial charge–discharge efficiency and capacity retention property of the cell with PPESK/PVDF/PPESK are better than those with PVDF separator or PPESK separator. In addition, when the mass ratio between PPESK and PVDF resins is increased to 4:3, PPESK/PVDF/PPESK separators show good thermal dimensional stability even thermally treated at 180 °C for 1 h.     

无机超细粉体改性锂离子电池隔膜的研究进展

综述了近年来无机超细粉体改性锂离子电池隔膜的研究进展,首先介绍了已在锂电隔膜改性上商业应用的Al₂O₃和AlOOH对传统聚烯烃膜和新型静电纺丝膜的改性方法和改性效果,随后又对常规无机材料TiO₂和SiO₂粉体对锂电隔膜的改性进行了叙述,最后对BN等非常规隔膜改性无机材料进行了简介;总结和讨论了无机材料改性后隔膜的组分、结构和性能对锂离子电池综合性能的影响,并对其无机材料改性锂电池隔膜的未来发展趋势进行了展望。     

Potential application of microporous structured poly(vinylidene fluoride-hexafluoropropylene)/poly(ethylene terephthalate) composite nonwoven separators to high-voltage and high-power lithium-ion batteries

We demonstrate potential application of a new composite non-woven separator, which is comprised of a phase inversion-controlled, microporous polyvinylidene fluoride-hexafluoropropylene (PVdF-HFP) gel polymer electrolyte and a polyethylene terephthalate (PET) non-woven support, to high-voltage and high-power lithium-ion batteries. In comparison to a commercialized polyethylene (PE) separator, the composite non-woven separator exhibits distinct improvements in microporous structure and liquid electrolyte wettability. Based on the understanding of the composite non-woven separator, cell performances of the separator at challenging charge/discharge conditions are investigated and discussed in terms of ion transport of the separator and AC impedance of the cell. The aforementioned advantageous features of the composite non-woven separator play a key role in providing facile ion transport and suppressing growth of cell impedance during cycling, which in turn contribute to superior cell performances at harsh charge/discharge conditions such as high voltages and high current densities.     

Battery performance of PMMA-grafted PE separators prepared by pre-irradiation grafting technique

Poly(methyl methacrylate)-grafted polyethylene (PE-g-PMMA) separators were prepared by pre-irradiation grafting technique of methyl methacrylate onto a commercial polyethylene separator. The prepared separators were characterized by using charge/discharge (C/D) cycling test, AC impedance, and thermal stability analyses. Thermal shrinkage (TS) of the PE-g-PMMA separators decreased with an increasing degree of grafting up to 70% above which it was saturated. The PE-g-PMMA separators showed a better oxidation stability on the anode up to 5 V and a better cycle life performance than the original PE separator. These characteristics make the prepared separators suitable for applications in high voltage secondary lithium batteries.     

Heat resistant microporous membranes based on soluble poly(aryl ether ketone) copolymers for lithium ion battery separator

To improve the safety and electrochemical properties of lithium ion batterie (LIB), a series of novel organic soluble poly(aryl ether ketone) (PAEK) copolymers were synthesized and used to fabricate LIB separators. The PAEK copolymers exhibited superior structural thermal stability and flame retardant, with glass transition temperature (T_g) above 150°C, oxygen index above 30 and no thermal decomposition before 500°C. Accordingly, the fabricated separators exhibited superior dimensional stability. The mechanical properties and electrolyte uptakes of the separators, as well as the electrochemical properties of the cells assembled with the separators were affected by the morphology and porosity of the separators. The separators with sponge-like structure exhibited less electrolyte uptakes but better mechanical properties than that of the ones with finger-like structure. The cell with finger-like structure separator exhibited poorer electrochemical properties than sponge-like structure separator, which might be caused by the collapse of some finger hole during the assemble process due to its poor mechanical properties. The charge–discharge performances of the cells after treated at 150°C demonstrates that the PAEK separators could be promising candidates for high-safety LIB.     

隔膜中残油量对锂电池性能的影响

锂离子电池隔膜在锂离子电池中主要起隔绝正负极防止短路和允许锂离子导通的作用[1],因此,锂离子电池隔膜品质的优劣直接影响到锂离子电池的应用性能。在锂电池隔膜制备的过程中,以石蜡油作为造孔剂,用热致相分离法制备聚乙烯微孔膜,石蜡油的残留不可避免。本文研究了隔膜中石蜡油的残留量对电池自放电、倍率放电、高温存储、循环性能等应用性能的影响。研究结果表明,残油量越低锂电池的应用性能越优。     

陶瓷复合锂离子电池隔膜研究进展

相对于传统锂离子电池隔膜,有机-无机陶瓷复合隔膜兼具有机材料的柔韧性、无机材料的耐温性和电解液亲和性。本文对锂离子电池用陶瓷复合隔膜进行综述,首先介绍了此类隔膜相对于传统隔膜的优势,其次对目前研究的陶瓷锂离子电池隔膜的结构形式和主要成膜材料进行了讨论,并介绍了国内外主要公司的陶瓷复合隔膜的研究和发展现状,最后对陶瓷复合隔膜的应用前景和面临的挑战进行了简要分析。鉴于该新型隔膜的优势,随着锂离子电池在高端电子产品以及动力、储能等新兴领域的发展,高安全性陶瓷复合锂离子电池隔膜必将代替传统的聚烯烃隔膜,成为主流隔膜满足人们的需要。     

Battery separators

The ideal battery separator would be infinitesimally thin, offer no resistance to ionic transport in electrolytes, provide infinite resistance to electronic conductivity for isolation of electrodes, be highly tortuous to prevent dendritic growths, and be inert to chemical reactions. Unfortunately, in the real world the ideal case does not exist. Real world separators are electronically insulating membranes whose ionic resistivity is brought to the desired range by manipulating the membranes thickness and porosity. It is clear that no single separator satisfies all the needs of battery designers, and compromises have to be made. It is ultimately the application that decides which separator is most suitable. We hope that this paper will be a useful tool and will help the battery manufacturers in selecting the most appropriate separators for their batteries and respective applications. The information provided is purely technical and does not include other very important parameters, such as cost of production, availability, and long-term stability. There has been a continued demand for thinner battery separators to increase battery power and capacity. This has been especially true for lithiumion batteries used in portable electronics. However, it is very important to ensure the continued safety of batteries, and this is where the role of the separator is greatest. Thus, it is essential to optimize all the components of battery to improve the performance while maintaining the safety of these cells. Separator manufacturers should work along with the battery manufacturers to create the next generation of batteries with increased reliability and performance, but always keeping safety in mind. This paper has attempted to present a comprehensive review of literature on separators used in various batteries. It is evident that a wide variety of separators are available and that they are critical components in batteries. In many cases, the separator is one of the major factors limiting the life and/or performance of batteries. Consequently, development of new improved separators would be very beneficial for the advanced high capacity batteries.