title: End-of-life nickel-cadmium accumulators: characterization of electrode materials and industrial Black Mass.
abstract: The aim of this paper is the characterization of spent NiCd batteries and the characterization of an industrial Black Mass obtained after crushing spent NiCd batteries and physical separation in a treatment plant. The characterization was first performed with five cylindrical NiCd batteries which were manually dismantled. Their characterization includes mass balance of the components, active powders elemental analysis and phase identification by X-ray powder diffraction. Chemical speciation of the two metals was also investigated. For cadmium, speciation was previously developed on solid synthetic samples. In a spent battery, the active powders correspond to about 43% of the battery weight. The other components are the separator and polymeric pieces (5%), the support plates (25%) and the carbon steel external case (27%). The sequential procedure shows that the nickel in the positive powders from the dismantled Ni-Cd batteries is distributed between Ni0 (39.7%), Ni(OH)2 (58.5%) and NiOOH (1.8%). Cadmium in the negative powder is about 99.9% as the Cd(OH)2 form with 0.1% of metal cadmium. In the industrial Black Mass, the distribution of cadmium is the same, whereas the distribution of nickel is Ni0 (46.9%), Ni(OH)2 (43.2%) and NiOOH (9.9%). This material contains also 1.8% cobalt and approx. 1% iron.
authors.affiliation: a Groupe Chimie et Electrochimie des Matériaux , Institut Jean Lamour, CNRS - Université de Lorraine , 1 Boulevard Arago, Metz Cedex 3 57078 , France.
authors.forename: Claire
authors.initials: C
authors.lastname: Hazotte
authors.forename: Nathalie
authors.initials: N
authors.lastname: Leclerc
authors.forename: Sébastien
authors.initials: S
authors.lastname: Diliberto
authors.forename: Eric
authors.initials: E
authors.lastname: Meux
authors.forename: Francois
authors.initials: F
authors.lastname: Lapicque
mesh_terms: D002104:Cadmium / Q000032:analysis*; D019187:Cadmium Compounds / Q000032:analysis*; D004566:Electrodes; D059029:Electronic Waste / Q000032:analysis*; D006878:Hydroxides / Q000032:analysis*; D009532:Nickel / Q000032:analysis*
chemical_list: D019187:Cadmium Compounds; D006878:Hydroxides; D002104:Cadmium; C037473:nickel hydroxide; D009532:Nickel
keywords: Black Mass; cadmium; nickel; speciation; spent batteries