Improved NiMH performance by a surface treatment that creates magnetic Ni-clusters
2016 (English)In: International journal of hydrogen energy, ISSN 0360-3199, E-ISSN 1879-3487, Vol. 41, no 23, 9933-9938 p.Article in journal, Meeting abstract (Refereed) PublishedText
A surface treatment method has been developed to activate the surface of an AB(5) type (La-20 Ce-7 Pr-1 Nd-4 Al-2 Mn-5 Co-6 Ni-55) alloy. In the process the surface is covered with a porous surface layer containing needle shaped rare earth hydroxides after etching by a potassium hydroxide solution. TEM studies show in addition the presence of a denser surface oxide layer with embedded Ni containing clusters covering the bulk alloy. The magnetic properties of the alloy powders change with the surface treatment. In addition to a paramagnetic component of the bulk alloy, surface treated alloy also displays superparamagnetic and ferromagnetic properties. In electrochemical half-cell tests, the alloy shows better high-rate dischargeability with increasing presence of magnetic clusters in the metal hydride particles surface.
Place, publisher, year, edition, pages
2016. Vol. 41, no 23, 9933-9938 p.
Metal hydrides, NiMH batteries, Surface treatment, Ni clusters, Discharge kinetics, Rare earths hydroxides
Other Physics Topics Engineering and Technology
IdentifiersURN: urn:nbn:se:uu:diva-299714DOI: 10.1016/j.ijhydene.2016.01.145ISI: 000378359400029OAI: oai:DiVA.org:uu-299714DiVA: diva2:950015
1st International Symposium on Materials for Energy Storage and Conversion (ESC-IS), SEP 07-09, 2015, Middle E Tech Univ, Ankara, TURKEY