發(fā)布時間：2018-06-10 02:22

  本文選題：鋰離子電池 + 鋰電池正極材料��； 參考：《浙江大學(xué)》2017年碩士論文

【摘要】：目前,商業(yè)上廣泛應(yīng)用的鋰離子正極材料主要有LiCoO_2(LCO)層狀材料、尖晶石型LiMn204(LMO)材料、橄欖石型LiFeP04(LFP)材料和Li[NiCoMn]02(NCM)三元層狀材料。它們有各自的優(yōu)點,但也存在相應(yīng)的缺點。LMO具有三維鋰離子通道,工作電壓較高,資源豐富成本較低,環(huán)境友好污染小,尤其是安全性較好,是理想的鋰離子動力電池正極材料。然而,LMO可逆循環(huán)容量(110～120mAh/g)偏低,且充放電循環(huán)過程中由于錳的溶解、電解液分解以及Jahn-Teller效應(yīng)等原因,容量衰減較快。為此,論文引入高容量的第二正極材料,在正極中形成微電池,減少了LMO材料顆粒表面Li+的富集,抑制Jahn-Teller效應(yīng)以保持LMO晶體結(jié)構(gòu)的完整,從而獲得比容量高、長循環(huán)壽命的鋰離子電池正極材料。研究結(jié)果表明,由高電位LMO與低電位LFP、LCO、NCM材料組成的復(fù)合材料,具有比LMO更高的比容量和更好的循環(huán)壽命。復(fù)合材料放電時Li+先嵌入高電位LMO,再向低電位材料遷移,LMO顆粒表面富集的Li+嵌入低電位材料,減少了 LMO材料顆粒表面Li+的富集,穩(wěn)定材料結(jié)構(gòu),抑制其產(chǎn)生畸形應(yīng)變。充電過程中,Li+從低電位材料脫嵌,高電位LMO的Li+,再向低電位材料遷移,形成一種“階段脫鋰”過程,達到充電緩沖的目的,從而提升材料的充放電循環(huán)性能。優(yōu)化后的LMO-NCM復(fù)合材料表現(xiàn)出比容量高、倍率性能好、長循環(huán)壽命的優(yōu)異綜合性能。經(jīng)過放大實際生產(chǎn)出了電池模塊,其安全性能和電化學(xué)性能都達到了國家標準。市場化應(yīng)用表明,LMO-NCM電池模塊完全達到預(yù)期性能指標。
[Abstract]:At present, LiCoO2LCO-layered materials, spinel LiMn204LMO-based materials, olivine LiFeP04LFP-based materials and Li [NiCoMn] 02NCM-ternary laminated materials are widely used in commercial applications. They have their own advantages, but they also have some disadvantages. LMO has three dimensional lithium ion channels, high operating voltage, low cost of rich resources, less environmental friendly pollution, especially better safety. It is an ideal cathode material for lithium ion power battery. However, the reversible cycle capacity of LMO is low, and the capacity decreases rapidly due to the dissolution of manganese, decomposition of electrolyte and Jahn-Teller effect during charge-discharge cycle. Therefore, a high capacity second cathode material is introduced to form a microcell in the positive electrode, which reduces the concentration of Li on the surface of the LMO particles and suppresses the Jahn-Teller effect to maintain the integrity of the LMO crystal structure so as to obtain high specific capacity. Lithium ion battery cathode material with long cycle life. The results show that the composite composed of high potential LMO and low potential LFP LCONCM has higher specific capacity and better cycle life than LMO. Li intercalated into high potential LMOs during discharge and then migrated to low potential materials. Li embedded in low potential materials reduced Li enrichment on LMO particles, stabilized material structure and inhibited abnormal strain. During charging, Li is deintercalated from low potential material, Li with high potential LMO is transferred to low potential material, which forms a "phase delithium" process, which achieves the purpose of charging and buffering, thus improving the charge and discharge cycle performance of the material. The optimized LMO-NCM composites show high specific capacity, good rate performance and excellent comprehensive properties of long cycle life. After amplifying, the battery module is produced, and its safety and electrochemical performance are up to the national standard. Market application shows that the LMO-NCM battery module fully meets the expected performance targets.
【學(xué)位授予單位】：浙江大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2017
【分類號】：O646;TM912

【參考文獻】

相關(guān)期刊論文 前10條

1 李萌;邱景義;余仲寶;廖紅英;李冰川;;高功率鋰離子電池電解液中導(dǎo)電鋰鹽的新應(yīng)用[J];電源技術(shù);2015年01期

2 余志強;;鋰離子電池負極材料研究進展[J];寧波化工;2014年02期

3 毛敏;余新喜;王慶杰;張云朋;;電解液對鋰離子電池電化學(xué)性能的影響[J];電池工業(yè);2014年01期

4 黃麗宏;閔忠華;張勤勇;;鋰離子電池負極材料的研究現(xiàn)狀及研究方向[J];西華大學(xué)學(xué)報(自然科學(xué)版);2013年06期

5 廖紅英;李冰川;孟蓉;王莉;何向明;;鋰離子電池先進電解液[J];新材料產(chǎn)業(yè);2012年10期

6 武明昊;陳劍;王崇;衣寶廉;;鋰離子電池負極材料的研究進展[J];電池;2011年04期

7 孫學(xué)亮;秦秀娟;卜立敏;吳偉;;鋰離子電池碳負極材料研究進展[J];有色金屬;2011年02期

8 陳宜升;廖波;王銀杰;王波;;尖晶石LiMn_2O_4的容量衰減與性能改進[J];軍民兩用技術(shù)與產(chǎn)品;2007年03期

9 張海朗;周彤;;新型層狀Li-Co-Ni-Mn-O鋰離子電池正極材料的研究評述[J];現(xiàn)代化工;2006年S1期

10 唐致遠,盧星河,張娜;尖晶石型LiMn_2O_4電池材料的元素摻雜[J];化學(xué)通報;2005年05期

相關(guān)博士學(xué)位論文 前1條

1 莊全超;鋰離子電池電極界面特性研究[D];廈門大學(xué);2007年

，

本文編號：2001647