Journal of Power Sources 436 (2019) 226853 0378-7753/© 2019 Elsevier B.V. All rights reserved. Review article Review on clean recovery of discarded/spent lead-acid battery and trends of recycled products Mingyang Li a, b , Jiakuan Yang a, b, c, * , Sha Liang a, b , Huijie Hou a, b , Jingping Hu a, b , Bingchuan Liu a, b , R.Vasant Kumar d a School of Environmental Science and Engineering, Huazhong University of Science and Technology (HUST), 1037 Luoyu Road, Wuhan, 430074, China b Hubei Provincial Engineering Laboratory of Solid Waste Treatment, Disposal and Recycling, 1037 Luoyu Road, Wuhan, 430074, China c State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology (HUST), 1037 Luoyu Road, Wuhan, 430074, China d Department of Materials Science and Metallurgy, University of Cambridge, 27 Charles Babbage Road, Cambridge, CB3 0FS, United Kingdom HIGHLIGHTS � The latest progress on the clean recovery processes of spent LAB is reviewed. � The applications of the recovered products are reviewed. � Technological challenges in hydrometallurgical recovery process are summarized. � The trends of hydrometallurgical recovery of spent LAB are analyzed. A R T I C L E INFO Keywords: Spent lead-acid battery Environmentally-friendly processes Recovered product ABSTRACT Emissions of lead particulates, sulfur oxides and their potential environmental risks are received great attention in traditional pyrometallurgical process for recycling spent lead-acid battery. In recent years, environmentally- friendly processes operating at near ambient temperatures show a good prospect for the recovery of spent lead- acid batteries, including electrowinning, organic acid leaching-calcination, and alkaline leaching-crystallization processes. The recovered products such as leady oxide (mixture of PbO and metallic Pb) and pure lead oxide from hydrometallurgical processes could be directly re-utilized as active materials in manufacturing of new batteries. A hydrometallurgical recovery route can eliminate the smelting procedure for lead ingot production and the following steps of Ball-milling or Barton liquid lead atomizing for leady oxide production in conventional lead mass fow from spent lead-acid battery to new lead-acid battery. Two technological challenges in hydrometal- lurgical recovery process for spent lead-acid battery are recognized as: removal of impurity elements (such as Fe and Ba) and loop reuse for reducing dosage of leaching reagents. Bibliometric analysis of recovery of spent lead- acid battery based on recent publications from 1987 to 2018 shows that the organic acid leaching-calcination process is the most frequently published technology in hydrometallurgical processes, meanwhile leady oxide and lead oxide are the most recovered products. 1. Introduction Lead-acid battery (LAB) has widespread applications in uninter- rupted power supplies, electric vehicles, energy storage, traction and starting, lighting and ignition (SLI) batteries [1–3]. The signifcant ad- vantages of low-cost raw materials and maturity of the manufacturing technology have ensured continual growth in LAB production trend in recent decades and compare favourably with other key batteries such as lithium-ion, NiCd, NiMH batteries and also fuel cells [4]. LAB accounts for more than 50% of the secondary battery market in 2015 [5]. The lead resource for LAB production mainly comes from nearly equal proportion of primary lead and secondary lead resources. Primary lead resource is mainly in the form of minerals, such as cerussite (PbCO 3 ), galena (PbS), and anglesite (PbSO 4 ) [6]. Secondary lead resource arises * Corresponding author. School of Environmental Science and Engineering, Huazhong University of Science and Technology (HUST), 1037 Luoyu Road, Wuhan, 430074, China. E-mail address: jkyang@mail.hust.edu.cn (J. Yang). Contents lists available at ScienceDirect Journal of Power Sources journal homepage: www.elsevier.com/locate/jpowsour https://doi.org/10.1016/j.jpowsour.2019.226853 Received 25 February 2019; Received in revised form 17 June 2019; Accepted 3 July 2019