本文選題：氫氧化鎳 + 正極材料　； 參考：《北京有色金屬研究總院》2014年碩士論文

【摘要】：鎳氫電池是一種被廣泛使用的二次電池,已經(jīng)成為二次電池市場(chǎng)的主流產(chǎn)品,其具有高容量、低記憶效應(yīng)、環(huán)境友好、工藝成熟和造價(jià)低廉等諸多優(yōu)點(diǎn)。但隨著電池技術(shù)的發(fā)展,鎳氫電池的容量成為阻礙其進(jìn)一步發(fā)展的瓶頸,尤其是近年來(lái)電動(dòng)汽車(chē)(EV)對(duì)于電池容量的要求日益迫切,而鎳氫電池目前尚難以滿(mǎn)足。因此高容量將成為鎳氫電池下一步發(fā)展過(guò)程中的關(guān)鍵技術(shù)。鎳氫電池的容量由正極和負(fù)極中容量較低的短板來(lái)決定,而目前負(fù)極容量已經(jīng)遠(yuǎn)遠(yuǎn)超過(guò)正極容量,提高鎳氫電池容量的瓶頸即為正極材料容量。因此研發(fā)具有高容量的正極材料具有重要的意義。 傳統(tǒng)的鎳氫電池正極為β-氫氧化鎳,經(jīng)過(guò)多年研究和改良,其放電容量逐漸迫近理論容量289mAh/g,進(jìn)一步提升的空間有限,而α-氫氧化鎳由于電子轉(zhuǎn)移數(shù)較高,其理論容量高達(dá)479mAh/g,因此日益受到研究者的關(guān)注。但是其在堿性環(huán)境下結(jié)構(gòu)不穩(wěn)定,會(huì)自發(fā)轉(zhuǎn)變?yōu)棣?氫氧化鎳,循環(huán)穩(wěn)定性不佳,限制了其進(jìn)一步應(yīng)用。 本工作在總結(jié)了相關(guān)研究的基礎(chǔ)上,以錳摻雜為手段,設(shè)計(jì)和合成了一種具有混合相結(jié)構(gòu)的氫氧化鎳,以β相為基體提供結(jié)構(gòu)穩(wěn)定性,α相為增強(qiáng)相提高容量,綜合α相和β相的優(yōu)缺點(diǎn)實(shí)現(xiàn)互補(bǔ),以期得到具有優(yōu)良綜合性能的氫氧化鎳正極材料。 本工作首先系統(tǒng)的研究了混合相氫氧化鎳的合成條件,簡(jiǎn)要討論了共沉積合成的化學(xué)環(huán)境以及后處理過(guò)程對(duì)于產(chǎn)物的影響,同時(shí)通過(guò)正交試驗(yàn)和均勻設(shè)計(jì)試驗(yàn)兩種不同的實(shí)驗(yàn)設(shè)計(jì)方法,對(duì)于錳摻雜量、攪拌電機(jī)頻率、pH值這三項(xiàng)對(duì)于產(chǎn)物影響最大的因素進(jìn)行了詳細(xì)的分析。試驗(yàn)結(jié)果表明,錳摻雜量宜保持在10%-15%之間,過(guò)低的錳摻雜量無(wú)法有效地提高樣品的放電容量,而過(guò)高的錳摻雜量則有可能導(dǎo)致氫氧化鎳結(jié)構(gòu)損傷,劣化電極性能。攪拌電機(jī)頻率宜保持在30Hz左右,過(guò)低的攪拌電機(jī)頻率不利于Mn2+離子的氧化,從而導(dǎo)致α相含量偏低；過(guò)高的攪拌電機(jī)頻率則不利于金屬離子的共沉積,導(dǎo)致結(jié)晶狀況劣化。pH值則在試驗(yàn)范圍內(nèi)越高越有利于放電容量的提高,原因在于高pH值條件下的沉積有利于晶體缺陷的生成,從而提高氫氧化鎳的充放電效率。 為了進(jìn)一步研究錳摻雜混合相氫氧化鎳的形成機(jī)制和實(shí)際使用性能,本工作通過(guò)合成不同錳摻雜含量的氫氧化鎳并對(duì)其進(jìn)行物理化學(xué)表征,詳細(xì)探究了錳摻雜量對(duì)氫氧化鎳樣品的影響。結(jié)果顯示,隨著錳摻雜量的不斷提高,氫氧化鎳的晶體結(jié)構(gòu)由β相逐漸轉(zhuǎn)變?yōu)棣料?在這一轉(zhuǎn)變過(guò)程中出現(xiàn)了符合本實(shí)驗(yàn)設(shè)計(jì)的混合相氫氧化鎳結(jié)構(gòu)。同時(shí)隨著錳摻雜量的提高,嵌入氫氧化鎳層間的陰離子和水分子的數(shù)量也顯著增多,這些嵌入粒子一方面通過(guò)擴(kuò)大層間間距誘導(dǎo)了α相的生成,另一方面擴(kuò)大的層間間距又反過(guò)來(lái)使得更多的粒子可以嵌入層間。因此層間間距的擴(kuò)大與嵌入粒子的數(shù)量增多互相作用,共同誘導(dǎo)了氫氧化鎳的相轉(zhuǎn)變行為。通過(guò)對(duì)合成樣品的形貌分析可以看到,樣品在掃描電子顯微鏡下具有獨(dú)特的蜂窩狀微觀形貌,其有利于提高氫氧化鎳樣品的充放電效率。合成樣品的電化學(xué)性能測(cè)試表明,符合本實(shí)驗(yàn)設(shè)計(jì)結(jié)構(gòu)的混合相氫氧化鎳在0.2C充放電速率下不僅放電容量達(dá)到了330mAh/g,相比普通商用p-氫氧化鎳提高約16%,同時(shí)在充放電循環(huán)中保持了良好的結(jié)構(gòu)穩(wěn)定性,50次循環(huán)后容量沒(méi)有出現(xiàn)衰減現(xiàn)象。 為了滿(mǎn)足電動(dòng)汽車(chē)大功率動(dòng)力電池的需要,本工作進(jìn)一步對(duì)合成的混合相氫氧化鎳做了覆鈷處理,結(jié)果顯示包覆鉆氧化物樣品的粉末電阻明顯降低,電性能測(cè)試顯示盡管在0.2C下放電容量有一定衰減,但是在1C大電流充放電時(shí)相比未覆鈷樣品容量有較為明顯提升,因此其有望作為一種大功率高容量正極材料得到應(yīng)用。
[Abstract]:Ni MH battery is a widely used two battery. It has become the mainstream product in the two battery market. It has many advantages, such as high capacity, low memory effect, friendly environment, mature technology and low cost. But with the development of battery technology, the capacity of Ni MH battery has become a bottleneck that hinders its further development, especially in recent years. Electric vehicle (EV) is becoming more and more urgent for battery capacity, and Ni MH battery is still difficult to meet at present. Therefore, high capacity will be the key technology in the next development process of Ni MH battery. The bottleneck of the capacity of high nickel hydrogen battery is the capacity of cathode material. Therefore, developing high capacity cathode materials is of great significance.
The traditional nickel hydrogen battery positive electrode is beta - nickel hydroxide. After years of research and improvement, the discharge capacity is gradually approaching the theoretical capacity of 289mAh/g, and the space for further upgrading is limited, while the theoretical capacity of the alpha hydroxide nickel hydroxide is up to 479mAh/g because of the high electron transfer number, so it is increasingly concerned by the researchers. But the structure is in the alkaline environment. Instability will change spontaneously into beta nickel hydroxide, and its poor stability will limit its further application.
On the basis of the related research, a kind of nickel hydroxide with mixed phase structure is designed and synthesized with manganese doping as a method. The structure stability is provided with beta phase as the matrix, the alpha phase is enhanced to enhance the capacity and the advantages and disadvantages of the synthesis of alpha and beta phase are complementation, in order to obtain good comprehensive properties of nickel hydroxide. Material Science.
This work first systematically studied the synthesis conditions of the mixed phase nickel hydroxide, briefly discussed the chemical environment of the co deposition and the effect of the post-treatment process on the product. At the same time, two different experimental design methods, through orthogonal test and uniform design test, were used for the three items of manganese mixing, stirring motor frequency, and pH value. The test results show that the amount of manganese doping should be kept between 10%-15% and the low manganese doping amount can not effectively improve the discharge capacity of the sample, while the excessive manganese doping may lead to the damage of the nickel hydroxide structure and the deterioration of the electric polarity. The frequency of the stirred motor should be kept around 30Hz. The low frequency of the stirred motor is not conducive to the oxidation of Mn2+ ions, which leads to the low content of the alpha phase, and the high frequency of stirred motor is not conducive to the co deposition of metal ions. The higher the crystallization condition, the higher the.PH value in the test range is beneficial to the increase of discharge capacity. The reason is that the deposition of high pH is beneficial to the lack of crystal. Thus, the charge and discharge efficiency of nickel hydroxide is improved.
In order to further study the formation mechanism and practical performance of Mn doped nickel hydroxide, the physical and chemical characterization of nickel hydroxide with different manganese content was synthesized and the effect of manganese doping on the sample of nickel hydroxide was investigated in detail. The crystal structure is gradually transformed from beta phase to alpha phase. In the process of this transformation, the structure of the mixed phase nickel hydroxide which is in accordance with the experimental design has appeared. With the increase of manganese doping, the number of anions and water molecules embedded in the layer of nickel hydroxide increased significantly. These embedded particles have induced the alpha phase by expanding the interlayer space. The expansion of interlayer space on the other hand, in turn, makes more particles embedded in the interlayer. Therefore, the expansion of the interlayer space and the number of embedded particles interact with each other, which co induces the phase transition behavior of nickel hydroxide. The unique honeycomb micro morphology is beneficial to improve the charge discharge efficiency of the nickel hydroxide sample. The electrochemical performance test of the synthesized sample shows that the discharge capacity of the mixed phase nickel hydroxide conforming to the design structure is 330mAh/g at the charge discharge rate of 0.2C, and is about 16% higher than that of the ordinary commercial p- nickel hydroxide. The discharge cycle keeps good structural stability, and the capacity does not decay after 50 cycles.
In order to meet the needs of the high-power power battery of the electric vehicle, the composite phase of the mixed phase nickel hydroxide was further treated with cobalt treatment. The results showed that the powder resistance of the coated oxide sample was obviously reduced. The electrical performance test showed that although the discharge capacity was attenuated under the 0.2C, it was compared with the 1C when the high current charge and discharge were not covered. The cobalt sample capacity has been significantly improved, so it is expected to be used as a high-power, high capacity cathode material.
【學(xué)位授予單位】：北京有色金屬研究總院
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2014
【分類(lèi)號(hào)】：TM912

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 何向明;姜長(zhǎng)印;李穩(wěn);萬(wàn)春榮;;表面包覆改善球形Ni(OH)_2高溫性能的研究[J];稀有金屬材料與工程;2007年02期

2 周輝,任小華,蔣文全,李莉;國(guó)內(nèi)外球形氫氧化鎳性能比較與探討[J];電池;1997年06期

3 黃振謙,徐國(guó)榮,唐有根,劉開(kāi)宇;MH/Ni電池失效原因[J];電池;2000年06期

4 田吉平,郭少斌,陳啟斌,蘇俊彥;球形Ni(OH)_2XRD線(xiàn)譜與制備工藝的關(guān)系[J];電池;2002年02期

5 冷擁軍,劉兵,王鳳軍,周錦鑫,孝英,馬紫峰;鋁取代氫氧化鎳制備、結(jié)構(gòu)與電化學(xué)性能Ⅱ結(jié)構(gòu)分析[J];電源技術(shù);2000年06期

6 韓恩山;康紅欣;魏子海;張紅柳;;混合晶相氫氧化鎳的合成和性能研究[J];電源技術(shù);2007年05期

7 王新;符顯珠;梁營(yíng);廖代偉;;鎂摻雜氫氧化鎳的結(jié)構(gòu)和電化學(xué)性能[J];電源技術(shù);2007年09期

8 李玉霞;楊傳錚;婁豫皖;夏保佳;;MH/Ni電池充放電過(guò)程導(dǎo)電物理機(jī)制的研究[J];化學(xué)學(xué)報(bào);2009年09期

9 計(jì)芬;晁鋒剛;;化學(xué)絡(luò)合沉淀法制備球形氫氧化鎳的工藝研究[J];科技信息;2010年25期

10 顧琳;王劍華;郭玉忠;劉浪;;控制化學(xué)結(jié)晶法制備球形Ni(OH)_2的熱力學(xué)分析[J];南方金屬;2010年02期

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