Charge-discharge characteristics of TiV_(2.1)Ni_(0.3) alloy surface-modified by ball-milling with Ni or Raney Ni

摘要

For the purpose of improving the charge-discharge characteristics of the TiV_(2.1)Ni_(0.3) alloy, it was surface-modified by ball-milling with Ni and Raney Ni which worked as a catalyst for hydriding and dehydriding. The surface modification of the TiV_(2.1)Ni_(0.3) alloy with Ni decreased the maximum discharge capacity, but the cycle durability was greatly improved. On the other hand, the surface modification of the TiV_(2.1)Ni_(0.3) alloy with Raney Ni improved both the discharge capacity and cycle durability. The surface modification of the TiV_(2.1)Ni_(0.3) alloy with Ni and Raney Ni suppressed the positive shift of the plateau potential in the discharge curve and the negative shift of the rest potential. In particular, Ni was more effective than Raney Ni. The high-rate dischargeability was improved by surface modification with Raney Ni.