<***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">由于納米硅對與鋰電池的高吸收率，將納米硅（上海超威納米<***N lang=EN-US>www.cwnano.com<***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">提供納米硅）用于鋰電池可以大幅度提高鋰電池的容量（理論可以達(dá)到<***N lang=EN-US>4000mA/h)<***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">。以納米**和石墨為原料<***N lang=EN-US>,<***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">替代納米碳粉，作為鋰電池負(fù)極材料，利用機(jī)械球磨的方法制備了硅<***N lang=EN-US>/<***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">石墨復(fù)合物<***N lang=EN-US>, <***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">采用<***N lang=EN-US>XRD<***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">、<***N lang=EN-US>SEM<***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">以及電化學(xué)測試等手段對材料進(jìn)行了結(jié)構(gòu)表征和性能測試<***N lang=EN-US>.<***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">通過球磨不同質(zhì)量比的硅和石墨<***N lang=EN-US>, <***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">并對相應(yīng)的復(fù)合物進(jìn)行充放電測試<***N lang=EN-US>, <***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">尋找到了硅和石墨的**比例<***N lang=EN-US>, <***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">其值為<***N lang=EN-US>1<***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">∶<***N lang=EN-US>9<***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">。組成<***N lang=EN-US>Si-C<***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">復(fù)合材料，可以有效的降低由于硅吸收鋰離子時(shí)的膨脹，同時(shí)可以加大與電解液的親和力，易與分散，提高循環(huán)性能。用納米**做成納米硅線用在充電鋰電池負(fù)極材料里，或者在納米**表面包覆石墨用做充電鋰電池負(fù)極材料，可以提高了充電鋰電池<***N lang=EN-US>3<***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">倍以上的電容量和充放電循環(huán)次數(shù)。實(shí)驗(yàn)結(jié)果表明<***N lang=EN-US>, <***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">所得材料既具備高于純納米硅的循環(huán)性能<***N lang=EN-US>, <***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">又具有比石墨高的可逆容量，同時(shí)大幅度提高鋰電池容量。

<***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">當(dāng)硅與石墨的質(zhì)量比為<***N lang=EN-US>4:6<***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">時(shí)，容量衰減較快<***N lang=EN-US>,25<***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">次循環(huán)后容量為<***N lang=EN-US>200mA.h/g,<***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">故復(fù)合物中硅的含量不能太大<***N lang=EN-US>.<***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">如果硅的含量較大，導(dǎo)致石墨不能很好地將硅分散開，納米硅之間接觸的機(jī)會增多，發(fā)生團(tuán)聚，庫侖效率和循環(huán)性能就會隨之下降<***N lang=EN-US>.<***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">硅和石墨質(zhì)量比為<***N lang=EN-US>3:7<***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">時(shí)，復(fù)合物<***N lang=EN-US>25<***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">次循環(huán)后的可逆容量雖然大于硅與石墨質(zhì)量比為<***N lang=EN-US>4:6<***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">（約<***N lang=EN-US>240mA.h/g<***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">）時(shí)的可逆容量，但從曲線上看出，衰減還是很快<***N lang=EN-US>.<***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">可見硅與石墨質(zhì)量比為<***N lang=EN-US>1:9<***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">和<***N lang=EN-US>2:8<***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">時(shí)，循環(huán)性能較好，而<***N lang=EN-US>1:9<***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">時(shí)為**<***N lang=EN-US>.<***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">由于納米硅的價(jià)格又遠(yuǎn)高于石墨，故如應(yīng)用于生產(chǎn)實(shí)踐，硅和石墨比為<***N lang=EN-US>1:9<***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">更為經(jīng)濟(jì)<***N lang=EN-US>.<***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">與純石墨比較，質(zhì)量比<***N lang=EN-US>1:9<***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">的復(fù)合物**可逆容量大大提高，是石墨的兩倍多<***N lang=EN-US>.<***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">循環(huán)性能也較好<***N lang=EN-US>,30<***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">次循環(huán)后達(dá)到<***N lang=EN-US>310mA.h/g.

<***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">硅及含硅材料作為鋰離子電池負(fù)極材料具有很高的比容量，硅的理論容量為<***N lang=EN-US>4200mA.h/g<***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">，機(jī)械球磨法制備的石墨<***N lang=EN-US>/<***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">納米硅復(fù)合物被用作鋰離子電池負(fù)極材料<***N lang=EN-US>.<***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">該復(fù)合材料體現(xiàn)了硅儲鋰量高及石墨循環(huán)性能良好、體積效應(yīng)小的特點(diǎn)<***N lang=EN-US>.<***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">實(shí)驗(yàn)結(jié)果得出**的硅<***N lang=EN-US>/<***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">石墨質(zhì)量比為<***N lang=EN-US>1:9 .<***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">電化學(xué)性能測試表明復(fù)合材料循環(huán)性能相對純硅電極有很大改善且具有高于石墨的可逆容量，有望代替石墨成為新一代鋰離子電池負(fù)極材料。

<***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">作為鋰離子電池負(fù)極材料，納米硅（上海超威納米<***N lang=EN-US>www.cwnano.com<***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">提供納米硅）具有**理論比容量（達(dá)<***N lang=EN-US>4200mAh/g)<***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">，遠(yuǎn)遠(yuǎn)高于目前廣泛應(yīng)用的碳材料，但是硅作為鋰離子電池負(fù)極的**缺點(diǎn)就是在與鋰合金化的過程中，伴隨著很大的體積變化，在循環(huán)過程中會造成活性物質(zhì)的脫落使容量很快衰減，循環(huán)性能很差。目前為了解決這個問題，有研究者把納米硅<***N lang=EN-US>/<***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">納米氮化鈦<***N lang=EN-US>/<***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">納米碳化鈦三種材料作為復(fù)合材料，實(shí)驗(yàn)表明它們具有穩(wěn)定的循環(huán)性能，<***N lang=EN-US>TiN,TiC <***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">等相作為惰性組分起到了穩(wěn)定結(jié)構(gòu)的作用，其作用主要表現(xiàn)在：在放電過程中，對于<***N lang=EN-US>LiSi<***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">形成過程中的體積膨脹起到緩沖作用，抑制由于合金粉化，從電極上剝落而引起的容量衰減，在充電過程中，又起到阻止<***N lang=EN-US>Si<***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">微粒團(tuán)聚的作用。另外，<***N lang=EN-US>TiN,TiC <***N style="FONT-FAMILY: 宋體; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">等相的導(dǎo)電性都較好，有增強(qiáng)電極導(dǎo)電性的作用。