本文選題：LiFePO_4/C + Li_3V_2(PO_4)_3/C　； 參考：《哈爾濱工業(yè)大學(xué)》2011年碩士論文

【摘要】：伴隨著科技的不斷進步,能源與環(huán)境問題日趨嚴重,這就對電池產(chǎn)業(yè)提出了更高的要求。鋰離子電池因其具有的良好的電池性能和綠色環(huán)保特性而備受推崇�，F(xiàn)在鋰離子電池發(fā)展的關(guān)鍵就是正極材料。磷酸鹽系正極材料憑借其電化學(xué)性能良好、結(jié)構(gòu)穩(wěn)定、安全性好、價格低等優(yōu)點而引起了廣泛關(guān)注。磷酸鹽系正極材料的電子導(dǎo)電率和離子導(dǎo)電率均較低,這是限制其進一步發(fā)展的最大阻礙。 本文對鋰離子電池的情況進行了概述并對鋰離子電池正極材料的發(fā)展現(xiàn)狀及存在問題進行了詳細評述。研究了使用靜電紡絲法制備磷酸鹽系鋰離子電池正極材料的工藝條件,并對所得的磷酸鐵鋰和磷酸釩鋰材料通過SEM、XRD和電化學(xué)測試等手段對材料的表面微觀形貌、晶體結(jié)構(gòu)和電化學(xué)性能等進行了考察。 采用靜電紡絲法制備了LiFePO_4/C和摻雜石墨的LiFePO_4/C納米材料。通過調(diào)整無機鹽和聚乙烯吡咯烷酮的含量配制了多種前驅(qū)液,獲取了多種紡絲材料。通過燒結(jié)后的SEM測試結(jié)果來看,PVP的量對于材料的棒狀形貌保持有很重要的作用。摻雜石墨首先可以提高紡絲效果,其次可以大幅度提高材料的電子電導(dǎo)。另外通過加入光照加熱的手段來減少材料的膠粘現(xiàn)象,通過這一手段制備出的材料的首次放電容量達到了154mAh/g。 采用靜電紡絲法制備了Li_3V_2(PO_4)_3/C納米材料。通過不斷調(diào)整確定了基礎(chǔ)的前驅(qū)液配制方案,并在此基礎(chǔ)之上進行了大量的改進工作。從燒結(jié)材料的SEM圖像來看,材料的形貌從最初的塊狀形貌變?yōu)榱诵〉念w粒,但始終無法形成棒狀形貌。 采用靜電紡絲法制備了LiFe_xV_(1-x)PO_4和LiFePO_4/Li_3V_2(PO_4)_3的同軸復(fù)合材料。從SEM結(jié)果來看,LiFe_xV_(1-x)PO_4材料的形貌基本為良好的棒狀形貌,摻雜后材料的電化學(xué)性能有了明顯提升。同軸復(fù)合材料在形貌上則是不規(guī)則的,為棒狀和小顆粒相互粘連的。這種材料的循環(huán)伏安曲線同時存在著LiFePO_4和Li_3V_2(PO_4)_3的氧化還原峰,說明兩種材料都形成了完整的晶形。
[Abstract]:With the development of science and technology, energy and environment problems become more and more serious, which puts forward higher requirements for battery industry.Lithium ion batteries are highly praised for their good battery performance and green environmental protection.The key to the development of lithium-ion batteries is cathode materials.Phosphate cathode materials have attracted wide attention due to their good electrochemical properties, stable structure, good safety and low price.The electronic conductivity and ionic conductivity of phosphate cathode materials are low, which is the biggest hindrance to their further development.In this paper, the situation of lithium ion battery is summarized, and the development status and existing problems of cathode material for lithium ion battery are reviewed in detail.The preparation conditions of cathode materials for phosphate-based lithium ion batteries by electrospinning method were studied. The surface morphology of the materials were investigated by means of SEM XRD and electrochemical measurements.The crystal structure and electrochemical properties were investigated.LiFePO_4/C and graphite doped LiFePO_4/C nanomaterials were prepared by electrostatic spinning.By adjusting the contents of inorganic salts and polyvinylpyrrolidone, a variety of precursor fluids were prepared and various spinning materials were obtained.The results of sintered SEM show that the amount of SEM plays an important role in maintaining the rod-like morphology of the materials.The doped graphite can improve the spinning effect first, and then the electronic conductivity of the material can be greatly improved.In addition, the adhesive phenomenon was reduced by adding light heating, and the first discharge capacity of the material was up to 154mAh/ g.Li_3V_2(PO_4)_3/C nanomaterials were prepared by electrostatic spinning.Through continuous adjustment, the basic precursor formulation scheme is determined, and a lot of improvement work is carried out on this basis.From the SEM images of the sintered materials, the morphology of the sintered materials changed from the initial bulk morphology to the small particles, but the rod morphology could not be formed at all times.Coaxial composites of LiFe_xV_(1-x)PO_4 and LiFePO_4/Li_3V_2(PO_4)_3 were prepared by electrostatic spinning.The results of SEM show that the morphology of LiFex\\\ -\\\The coaxial composites are irregular in morphology and stick and small particles adhere to each other.The redox peaks of LiFePO_4 and Li_3V_2(PO_4)_3 exist at the same time in the cyclic voltammetry curve of this material, which indicates that both materials form a complete crystal shape.
【學(xué)位授予單位】：哈爾濱工業(yè)大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2011
【分類號】：TM912.9

【參考文獻】

相關(guān)期刊論文 前10條

1 趙中琴;吳中友;楊武保;劉鑫;江衛(wèi)軍;;一種新型硅碳復(fù)合薄膜材料作為鋰離子二次電池負極材料的研究(英文)[J];北京大學(xué)學(xué)報(自然科學(xué)版);2006年S1期

2 廖文明;戴永年;姚耀春;易惠華;熊學(xué);;4種正極材料對鋰離子電池性能的影響及其發(fā)展趨勢[J];材料導(dǎo)報;2008年10期

3 葛昊;李寧;黎德育;;鋰離子電池負極材料Li_4Ti_5O_(12)的研究進展[J];稀有金屬材料與工程;2007年S3期

4 任學(xué)佑;鋰離子電池及其發(fā)展前景[J];電池;1996年01期

5 田志宏;趙海雷;王治峰;仇衛(wèi)華;;改善Li_4Ti_5O_(12)倍率性能的研究進展[J];電池;2008年03期

6 梁英;饒睦敏;蔡宗平;趙靈智;李偉善;;鋰離子電池正極材料LiMn_2O_4改性研究進展[J];電池工業(yè);2009年01期

7 蔡金書;黃令;柯福生;孫世剛;;納米Sn-Co/石墨復(fù)合材料的制備、結(jié)構(gòu)和電化學(xué)性能[J];電化學(xué);2009年01期

8 趙煜娟,夏定國,劉慶國;鋰離子蓄電池正極材料LiNi_(0.85)Co_(0.1)M_(0.05)O_2的合成及性能[J];電源技術(shù);2003年05期

9 劉素琴;李世彩;黃可龍;;Li_3V_2(PO_4)_3/C復(fù)合正極材料的制備與性能[J];電源技術(shù);2007年06期

10 滕祥國;趙永濤;武增華;席靖宇;邱新平;陳立泉;;溫度對釩電池性能的影響[J];電源技術(shù);2009年07期

相關(guān)博士學(xué)位論文 前1條

1 陳晗;新型鋰離子電池正極材料LiFePO_4的合成及改性研究[D];湖南大學(xué);2007年

相關(guān)碩士學(xué)位論文 前5條

1 王歡;鋰離子電池正極材料LiFePO_4/C的制備及改性[D];哈爾濱工業(yè)大學(xué);2010年

2 于娜;靜電紡絲技術(shù)制備無機復(fù)合納米纖維材料[D];東北師范大學(xué);2006年

3 夏繼才;橄欖石型正極材料磷酸亞鐵鋰的摻雜改性研究[D];哈爾濱工業(yè)大學(xué);2006年

4 劉芳芳;溶膠凝膠法結(jié)合電紡技術(shù)合成納米結(jié)構(gòu)纖維及其電化學(xué)性質(zhì)研究[D];山東大學(xué);2008年

5 劉靜濤;正極材料Li_3V_2（PO_4）_3溶膠—凝膠法的制備及性能研究[D];哈爾濱工業(yè)大學(xué);2007年

，

本文編號：1760281