【摘要】：凝膠聚合物鋰離子電池是在液態(tài)鋰離子電池的基礎(chǔ)上發(fā)展起來的新一代可充電鋰離子電池,它不僅具有液態(tài)鋰離子電池的高電壓、高能量密度、長循環(huán)壽命等特點(diǎn),而且改善了液態(tài)鋰離子電池可能出現(xiàn)的漏液、爆炸等問題,電池的外形設(shè)計組裝也靈活方便,廣泛應(yīng)用于電動汽車、移動通訊等領(lǐng)域。因此,對凝膠聚合物電解質(zhì)膜的需求也日益增加,凝膠聚合物電解質(zhì)膜的研究也得到了眾多研究者的關(guān)注。 本文主要研究了基于聚丙烯酸酯類基體的兩類凝膠聚合物電解質(zhì)(GPE)：首先以甲基丙烯酸甲酯(MMA)和馬來酸酐(MAh)為單體合成共聚物P(MMA-MAh),然后在此共聚物基礎(chǔ)上引入聚乙二醇1500(PEG33),合成得到新型交聯(lián)聚合物P(MMA-MAh)-PEG33,并分別以兩種聚合物為基體,碳酸丙烯酯(PC)為增塑劑,LiClO4為鋰鹽制備凝膠聚合物電解質(zhì)。采用傅里葉紅外光譜(FTIR)、X射線衍射法(XRD)、差示掃描量熱法(DSC)、熱失重分析(TGA)對合成的兩種聚合物進(jìn)行表征,采用交流阻抗法對制備的兩種凝膠聚合物電解質(zhì)體系的導(dǎo)鋰離子性能作了研究,并且分析了不同溫度和配比對其離子電導(dǎo)率的影響。 結(jié)果表明,成功合成了非晶無定形結(jié)構(gòu)的共聚物P(MMA-MAh)和交聯(lián)聚合物P(MMA-MAh)-PEG33。交聯(lián)聚合物的玻璃化轉(zhuǎn)變溫度Tg為124℃,比共聚物的Tg(133℃)要低,前者的熱分解溫度為358℃,比后者的熱分解溫度(349℃)要高。兩種聚合物基GPE的成膜性較好,結(jié)構(gòu)比較穩(wěn)定,當(dāng)添加的聚合物基體與液體電解液的質(zhì)量比為50：50時,GPE的失重率較低,保液性能較好,交聯(lián)聚合物P(MMA-MAh)-PEG33基GPE的最小失重率為32.23%,共聚物P(MMA-MAh)基GPE的最小失重率為29.23%,兩者的保液性能相差不大。兩種聚合物基GPE體系的離子電導(dǎo)率均隨溫度的升高而增大,隨聚合物含量的增加而減小,且在研究溫度范圍(0-40℃)內(nèi)鋰離子遷移符合Arrhenius方程。當(dāng)交聯(lián)聚合物質(zhì)量含量為50%時,其凝膠聚合物電解質(zhì)在室溫下的離子電導(dǎo)率達(dá)8.66×10-5S/cm,比共聚物基凝膠聚合物電解質(zhì)在相同情況下的室溫離子電導(dǎo)率(4.61×10-5S/cm)要高。另外,交聯(lián)聚合物體系的活化能值均小于共聚物體系的活化能值,這是因為交聯(lián)結(jié)構(gòu)更有利于鋰離子的遷移,賦予其擁有相對于共聚物更優(yōu)異的性能,使其更加滿足鋰離子電池的使用需要。
[Abstract]:Gel polymer lithium ion battery is a new generation of rechargeable lithium ion battery based on liquid lithium ion battery. It not only has the characteristics of high voltage, high energy density and long cycle life of liquid lithium ion battery. It also improves the problems of liquid lithium-ion battery such as leakage, explosion and so on. The configuration design and assembly of the battery is also flexible and convenient. It is widely used in electric vehicle, mobile communication and other fields. Therefore, the demand for gel polymer electrolyte membrane is increasing day by day, and the research of gel polymer electrolyte membrane has been paid attention by many researchers. In this paper, two kinds of gel polymer electrolyte (GPE): based on polyacrylate matrix were studied. Firstly, the copolymers P (MMA-MAh) were synthesized with methyl methacrylate (MMA) and maleic anhydride (MAh) as monomers. A new crosslinked polymer P (MMA-MAh)-PEG33, was synthesized by introducing polyethylene glycol 1500 (PEG33) on the basis of the copolymer. Two kinds of polymers were used as matrix and propylene carbonate (PC) as plasticizer, respectively. LiClO4 was used as lithium salt to prepare gel polymer electrolyte. Two kinds of synthesized polymers were characterized by (XRD), differential scanning calorimetry (DSC),) and thermogravimetric analysis (TGA) by Fourier transform infrared (FTIR) (FTIR), X ray diffraction. The lithium ion conductivity of two kinds of gel polymer electrolytes was studied by AC impedance method, and the effects of different temperature and ratio on ionic conductivity were analyzed. The results show that the amorphous copolymer P (MMA-MAh) and the crosslinked polymer P (MMA-MAh)-PEG33. have been successfully synthesized. The glass transition temperature (Tg) of the crosslinked polymer is 124 鈩，

本文編號：2341189