Characterization of spent nickel–metal hydride batteries and a preliminary economic evaluation of the recovery processes

Abstract

Valuable metal materials can be recovered from spent nickel-metal hydride (NiMH) batteries. However, little attention has been paid to the metal compositions of individual components of NiMH batteries, although this is important for the selection of the appropriate recycling process. In this study, NiMH batteries were manually disassembled to identify the components and to characterize the metals in each of these. A preliminary economic analysis was also conducted to evaluate the recovery of valuable metals from spent NiMH batteries using thermal melting versus simple mechanical separation. The results of this study show that metallic components account for more than 60% of battery weight. The contents of Ni, Fe, Co, and rare earth elements (REEs) (i.e., valuable metals of interest for recovery) in a single battery were 17.9%, 15.4%, 4.41%, and 17.3%, respectively. Most of the Fe was in the battery components of the steel cathode collector, cathode cap, and anode metal grid, while Ni (>90%) and Co (>90%) were mainly in the electrode active materials (anode and cathode metal powders). About 1.88 g of REEs (Ce, La, and Y) could be obtained from one spent NiMH battery. The estimated profits from recovering valuable metals from spent NiMH batteries by using thermal melting and mechanical processes are 2,329 and 2,531 USD/ton, respectively, when including a subsidy of 1,710 USD/ton. The findings of this study are very useful for further research related to technical and economic evaluations of the recovery of valuable metals from spent NiMH batteries.Implications: The spent nickel-metal hydride (NiMH) batteries were manually disassembled and their components were identified. The metals account for more than 60% of battery weight, when Ni, Fe, Co, and rare earth elements (REEs) were 17.9%, 15.4%, 4.41%, and 17.3%, respectively, in a single battery. The estimated profits of recovering valuable metals from NiMH batteries by using thermal melting and mechanical processing are 2,329 and 2,531 USD/ton, respectively, when including a subsidy of 1,710 USD/ton. These findings are very useful to develop or select the recovery methods of valuable metals from spent NiMH batteries.PAPER HISTORY

Recovery of Lanthanum(III) and Nickel(II) Ions from Acidic Solutions by the Highly Effective Ion Exchanger

“…The Ni-MH batteries found applications in electric vehicles and portable electronic devices such as hybrid cars, cameras, laptops, and notebooks. These batteries are rich in nickel, cobalt, rare earth elements (i.e., lanthanum, cerium, praseodymium and neodymium), and iron [11]. Until now, the most economically essential metals applied in the nickel-metal hydride batteries production have been nickel and cobalt, but in the last decade rare earth elements gained importance as a significant material for the battery alloys production due to their increasing consumption.…”

“…The properly recycled batteries may contribute to obtaining possibly cheap metals sources. Therefore, appropriate recycling methods are constantly being developed [6,[10][11][12][13].…”

Simple Preparation of Ni and NiO Nanoparticles Using Raffinate Solution Originated from Spent NiMH Battery Recycling

“…Nickel-metal hydride (NiMH) batteries have been in the market since 1990, and this battery technology reached widespread application in a short time due to its good performance at both low and high temperatures, safety under extreme conditions, good consistency and environmental friendliness [25,26]. NiMH batteries are still extensively used in electric vehicles (EVs), hybrid electric vehicles (HEVs), portable power tools and modern military devices [25,26].…”

“…Nickel-metal hydride (NiMH) batteries have been in the market since 1990, and this battery technology reached widespread application in a short time due to its good performance at both low and high temperatures, safety under extreme conditions, good consistency and environmental friendliness [25,26]. NiMH batteries are still extensively used in electric vehicles (EVs), hybrid electric vehicles (HEVs), portable power tools and modern military devices [25,26]. According to market review [27], the consumption of NiMH batteries will increase slightly up until 2020; their waste is a valuable secondary source not only for Ni and cobalt (Co), but also for rare earth elements (REE) [26,28].…”

“…NiMH batteries are still extensively used in electric vehicles (EVs), hybrid electric vehicles (HEVs), portable power tools and modern military devices [25,26]. According to market review [27], the consumption of NiMH batteries will increase slightly up until 2020; their waste is a valuable secondary source not only for Ni and cobalt (Co), but also for rare earth elements (REE) [26,28]. In 2006, the European Union (EU) passed the Battery Directive, one of whose aims is a higher rate of battery recycling.…”