通过选择不同烧结工艺,探索了热压烧结法制备NiTi-Si复合电极材料的结构演化及其对电性能的影响.结果表明,烧结过程的压缩率随热压烧结温度的升高而演化,可分为三个阶段:第一阶段未产生压缩变形,第二阶段由于Si的软化开始产生压缩变形,第三阶段NiTi也开始软化,压缩率显著增加.用X射线衍射(XRD)和扫描电子显微镜(SEM)分析每个阶段的相组成及微观结构,结果表明,热压烧结样品组成主要是Ni4Ti4 Si7三元金属间化合物及部分Ni3Ti3O、NiTi与Si,复合物致密度也随着烧结温度的提高而改善.选取一组具代表性的NiTi-Si复合材料作为电极制备成纽扣电池,充放电曲线结果表明,电池在循环初期出现明显比容量衰减,但电池循环次数明显高于传统集电体Si电极材料.分析认为,Ni4Ti4Si7三元金属间化合物中的Si不参与电化学反应,但是该化合物有助于弛豫充放电过程中电极体积变化导致的应变.
参考文献
[1] | M. N. Obrovac;Leif Christensen .Structural Changes in Silicon Anodes during Lithium Insertion/Extraction[J].Electrochemical and solid-state letters,2004(5):A93-A96. |
[2] | Li J;Dahn JR .An in situ X-ray diffraction study of the reaction of Li with crystalline Si[J].Journal of the Electrochemical Society,2007(3):A156-A161. |
[3] | Seung-Joo Lee;Jong-Ki Lee;Sang-Hun Chung .Stress effect on Cycle properties of the silicon thin-film anode[J].Journal of Power Sources,2001(0):191-193. |
[4] | Maranchi JP;Hepp AF;Evans AG;Nuhfer NT;Kumta PN .Interfacial properties of the a-Si/Cu : active-inactive thin-film anode system for lithium-ion batteries[J].Journal of the Electrochemical Society,2006(6):A1246-A1253. |
[5] | Rasool Amini;Fatemeh Alijani;Mohammad Ghaffari.Formation of B19', B2, and amorphous phases during mechano-synthesis of nanocrystalline NiTi intermetallics[J].Powder Technology: An International Journal on the Science and Technology of Wet and Dry Particulate Systems,2014:797-802. |
[6] | Gyu-bong Cho;Bo-min Kim;Hee-jin Choi;Jung-pil Noh;Si-young Choi;Hyo-jun Ahn;Shuichi Miyazaki;Tae-hyun Nam .Shape memory effect-induced crack closure in Si thin film deposited on a Ti–50.3Ni (at%) alloy substrate[J].Journal of Alloys and Compounds: An Interdisciplinary Journal of Materials Science and Solid-state Chemistry and Physics,2010(1):L8-L12. |
[7] | Maranchi JP;Hepp AF;Evans AG;Nuhfer NT;Kumta PN .Interfacial properties of the a-Si/Cu : active-inactive thin-film anode system for lithium-ion batteries[J].Journal of the Electrochemical Society,2006(6):A1246-A1253. |
[8] | Hye Jin Kwon;Jong Jin Song;Deuk Kyu Ahn;Soon Ho Hong;Jong Soo Cho;Jeong Tak Moon;Keun Yong Sohn;Won-Wook Park .Microstructures and Electrochemical Properties of Si-xTiNi Alloys for Lithium Secondary Batteries[J].Journal of nanoscience and nanotechnology,2013(5):3417-3421. |
上一张
下一张
上一张
下一张
计量
- 下载量()
- 访问量()
文章评分
- 您的评分:
-
10%
-
20%
-
30%
-
40%
-
50%