## Determination of the hydrogen coefficient diffusion DH in the MmNi3.55Mn0.4Al0.3Co0.75-xFex (0 â‰¤ x â‰¤0.75) electrodes alloys by cyclic voltammetry

M. Ben Moussa , M. Abdellaoui , J. Lamloumi

International Journal of Chemistry, Mathematics And Physics(IJCMP), Vol-5,Issue-5, September - October 2021, Pages 1-6 , 10.22161/ijcmp.5.5.1 Download | Downloads : 8 | Total View : 2311 Article Info: Received: 10 Sep 2021; Received in revised form: 12 Oct 2021; Accepted: 20 Oct 2021; Available online: 31 Oct 2021 Abstract: The hydrogen storage alloys MmNi3.55Mn0.4Al0.3Co0.75-xFex (0 â‰¤ x â‰¤0.75) were used as negative electrodes in the Ni-MH accumulators. The chronopotentiommetry and the cyclic voltammetry were applied to characterize the electrochemical properties of these alloys. The obtained results showed that the substitution of the cobalt atoms by iron atoms has a good effect on the life cycle of the electrode. The discharge capacity reaches its maximum in MmNi3.55Mn0.4Al0.3Co0.75-x Fex ( x = 0, 0.15, 0.35, 0.55 and 0.75) are, respectively, equal to 270, 266, 260, 210 and 200 mAh/g after 12 charge-discharge cycles. The diffusion behaviour of hydrogen in the negative electrodes made from these alloys was characterized by cyclic voltammetry after few activation cycles. The values of the hydrogen coefficient in MmNi3.55Mn0.4Al0.3Co0.75-x Fex ( x = 0, 0.15, 0.35, 0.55 and 0.75) are, respectively, equal to 5.86 10-10, 1.95 10-9, 3.44 10-9, 2.96 10-9 and 4.98 10-10 cm2 s-1. However, the values of the charge transfer coefficients are respectively equal to 0.35, 0.6, 0.5, 0.33 and 0.3. These results showed that the substitution of cobalt by iron decreases the reversibility and the kinetic of the electrochemical reaction in these alloys. Keywords: life cycle, discharge capacity, hydrogen diffusion coefficient. References: [1] Hongge Pan, Yun Chen, Chunsheng Wang, J. X. Ma, C. P. Chen, Q. D. Wang, Electrochimica Acta 44 (1999) 2263-2269.[2] Hongge Pan, Jian Xin Ma, Chuncheng Wang, C. P. Chen, Q. D. Wang, Electrochemica Acta 44 (1999) 3977-3987.[3] Jian Xin Ma, Hongge Pan, Yunfeng Zhu, Shouquan Li, Chang Ping Chen, Qidong Wang, Electrochemica Acta 46 (2001) 2427-2434.[4] S.-R Chung, T.-P. Perng., Journal of Alloys and Compounds, 353 (2003) 289â€“294.[5] Chiaki Iwakwra, Kazuhiro Fukuda, Hiroshi Senoh, Hiroshi Inoue, Masao Matsuoka, Yoshifumi Yamamoto, Electrochimica Acta, Vol. 43,Nos. 14-15 (1998) 2041-2046.[6] R. Baddour-Hadjean, J. P. Pereira-Ramos, M. Latroche, A. Percheron-GuÃ©gan, ITE Letters on Batteries, New technologies & medicine, Vol. 1 (2000) 29-37.[7] H. Mathlouthi, C. Khaldi, M. Ben Moussa, J. Lamloumi, A Percheron-GuÃ©gan, Journal of Alloys and Compounds, 375 (2004) 297â€“304.[8] Chuan-Jian Li, Xin-Lin Wang, Chong-Yu wang, Journal of Alloys and compounds, 293-295 (1999) 742â€“746.[9] Xianxia Yang, Naixin Xu, Journal of Alloys and Compounds, 316 (2001) 113â€“117.[10] Qin Lin, Shuang Zhao, Da-jian Zhu, Bo Song,Zhang Mei, Journal of Alloys and compounds, 351 (2003) 91-94.[11] Chuan-jian Li, Feng-Rong Wang, Wen-Hao Cheng, Wei Li, Wen-Tong Zhoo, Journal of Alloys and compounds, 315 (2001) 218â€“223.[12] M. Ben Moussa, M. Abdellaoui, C. Khaldi, H. Mathlouthi, J. Lamloumi, A. Percheron GuÃ©gan, Journal of Alloys and Compounds (2005), Article in press.[13] M. Ben Moussa, M. Abdellaoui, H. Mathlouthi, J. Lamloumi, A. Percheron GuÃ©gan, Journal of Alloys and Compounds (2005), Article in press.[14] H. Mathlouthi, J. Lamloumi, M. Latroche, A. Percheron GuÃ©gan, Ann. Chim. Sci. Matter. 22 (1999) 241.[15] Mingming Geng, Jian Wen Han, Feng Feng, Derek O. Northwood, International Journal of Hydrogen Energy 25 (2000) 203-210.[16] Mingming Geng, Jian Wen Han, Derek O. Northwood, J. Electrochem. Soc. 146 (7) (1999) 2271-2375.[17] Hongge Pan, Jianxin ma, chunsheng Wang, Shaoam Chen, Xinghua wang, Chanpping Chen, Qidong Wang, Journal of Alloys and Compounds, 293-295 (1999) 648â€“652.[18] Hongge Pan, Yongfeng Liu, Mingxia Gao, Yongquan Lei, Qidong Wang, Journal of the Electrochemical Society, 150 (5) (2003) A565-A570.[19] A. J. Bard, L. R. Fulkner, Electrochimie: Principes, Methodes et Applications, Masson, Paris, (1998).[20] H. Matsuda, Y. Ayabe, Z. Electrochem. 59 (1955) 494.[21] Chen Weixiang, Jouranl of Power Sources 90 (2000) 201-205.