Eect of alloys modi®ed by an alkaline solution containing potassium borohydride on the kinetic properties of MlNi3.7Co0.6Mn0.4Al0.3 hydride electrode
نویسندگان
چکیده
This paper describes the eects of treating the alloy powder of an electrode with 6 M KOH solution containing y M KBH4 ( y = 0.0, 0.005, 0.01, 0.02 and 0.03) on the kinetic properties of the electrode, including high rate dischargeablilty HRD, exchange current density I0, symmetry factor b, limiting current density IL, diusion coecient of hydrogen in the a-phase Da, and electrochemical polarization Ze and concentration polarization Zc. The results show that the kinetic parameters HRD, I0, IL and Da increase markedly with the increase in the concentration of KBH4, the Ze and Zc decrease rapidly with increasing concentration of KBH4, but the symmetry factor b does not change. # 1999 Elsevier Science Ltd. All rights reserved.
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