本文選題：熱電池　切入點(diǎn)：陰極材料　出處：《哈爾濱工業(yè)大學(xué)》2017年碩士論文

【摘要】：熱電池因具有儲(chǔ)存時(shí)間長(zhǎng)、激活迅速可靠、高比能量以及高比功率等優(yōu)良性能,在現(xiàn)代武器方面得到了廣泛應(yīng)用。隨著現(xiàn)代武器的飛速發(fā)展對(duì)熱電池又提出了新的要求。而陰極材料作為熱電池的重要組成部分,將直接影響整個(gè)電池系統(tǒng)的電性能。在熱電池陰極材料的研究中,釩氧化物因具有熱穩(wěn)定性好、電極電位和比功率高等優(yōu)勢(shì)而成為目前陰極材料研究的熱點(diǎn)。因此,釩氧化物的研究對(duì)熱電池的發(fā)展具有重要的意義和價(jià)值。本文對(duì)高溫固相法制備LVO(γ-LiV_2O_5+VO_2)陰極材料的工藝進(jìn)行了研究,采用SEM和XRD對(duì)材料進(jìn)行了物相結(jié)構(gòu)與形貌表征,結(jié)合不同工藝條件下單體電池的放電結(jié)果,對(duì)工藝參數(shù)進(jìn)行了優(yōu)化探究。研究結(jié)果表明,氬氣流速為90mL/min,氧化釩與溴化鋰質(zhì)量比4:1,550℃鋰化2 h時(shí),得到的產(chǎn)物純度高、結(jié)晶度好;此時(shí)單體電池放電的電極電位和比容量較高,但電池激活瞬間存在電壓尖峰和電壓滯后。分析了LVO單體電池電壓尖峰產(chǎn)生的原因。研究結(jié)果表明,向LVO陰極材料中添加2%的氧化鋰時(shí)電壓尖峰明顯減弱;研究了電解質(zhì)添加量對(duì)電池性能的影響,結(jié)果表明,添加適量的電解質(zhì)時(shí),能有效減小離子擴(kuò)散阻力和放電過(guò)程中的濃差極化,電壓下降緩慢,放電時(shí)間延長(zhǎng),提高了電池的深度放電能力;研究了碳材料對(duì)電壓滯后的影響,研究結(jié)果表明,添加少量碳材料能夠改善陰極材料的導(dǎo)電性,向其中添加1%的導(dǎo)電炭黑時(shí),電壓滯后被消除;尤其是當(dāng)石墨與導(dǎo)電炭黑復(fù)合添加時(shí),電壓滯后被消除的同時(shí)電池仍保持較高的電壓,電池內(nèi)阻也明顯減小。研究了溶膠凝膠法制備Li_(1+x)V_3O_8陰極材料的工藝,采用SEM和XRD對(duì)材料進(jìn)行了物相結(jié)構(gòu)與形貌表征。結(jié)合不同工藝條件下單體電池的放電結(jié)果,對(duì)工藝參數(shù)進(jìn)行了優(yōu)化探究。研究結(jié)果表明,鋰釩摩爾比為1.2:3、金屬離子與檸檬酸摩爾比為1:2、pH等于7、500℃燒結(jié)20 h時(shí)得到的產(chǎn)物純度高、顆粒呈較為規(guī)則的網(wǎng)絡(luò)結(jié)構(gòu),比表面大。單體電池放電電壓在2.50 V以上,放電至1.5 V的比容量較高。研究了電解質(zhì)添加量對(duì)電池性能的影響,研究結(jié)果表明,電解質(zhì)添加量為15%時(shí),電池放電電壓較為平穩(wěn),放電比容量較高;分析了導(dǎo)電炭黑對(duì)電壓滯后的影響,研究結(jié)果表明,導(dǎo)電炭黑添加量為10%時(shí),單體電池電壓滯后明顯減弱,電壓平穩(wěn)性好,電池內(nèi)阻降低;對(duì)電壓尖峰的改善進(jìn)行了研究,添加3%的氧化鋰時(shí),電壓尖峰被消除,但電池放電時(shí)間縮短。最后,對(duì)兩種釩氧化物陰極材料進(jìn)行了對(duì)比分析,LVO制備工藝操作簡(jiǎn)單,實(shí)驗(yàn)成本相對(duì)較低,Li_(1+x)V_3O_8陰極材料組裝的單體電池電壓更為平穩(wěn),放電比容量相對(duì)較高。
[Abstract]:Thermal batteries have been widely used in modern weapons due to their long storage time, rapid and reliable activation, high specific energy and high specific power.With the rapid development of modern weapons, new requirements for thermal batteries have been put forward.As an important part of thermal battery, cathode material will directly affect the electrical performance of the whole battery system.In the research of cathode materials for thermal batteries, vanadium oxide has become a hot research topic because of its advantages of good thermal stability, high electrode potential and high specific power.Therefore, the study of vanadium oxide is of great significance and value to the development of thermal battery.In this paper, the preparation process of LVO-LiV2O5V _ 2 cathode material by high-temperature solid-state method was studied. The phase structure and morphology of the material were characterized by SEM and XRD, and the discharge results of single cell under different process conditions were combined.The optimization of process parameters was studied.The results show that when the flow rate of argon is 90 mL / min and the mass ratio of vanadium oxide to lithium bromide is 4: 1550 鈩，

本文編號(hào)：1726157