Tremendous efforts are being made to develop electrode materials, electrolytes, and separators for energy storage devices to meet the needs of emerging technologies such as electric vehicles, decarbonized electricity, and electrochemical energy storage. However, the sustainability concerns of lithium-ion batteries (LIBs) and next-generation rechargeable batteries have received little attention. Recycling plays an important role in the overall sustainability of future batteries and is affected by battery attributes including environmental hazards and the value of their constituent resources. Therefore, recycling should be considered when developing battery systems. Herein, we provide a systematic overview of rechargeable battery sustainability. With a particular focus on electric vehicles, we analyze the market competitiveness of batteries in terms of economy, environment, and policy. Considering the large volumes of batteries soon to be retired, we comprehensively evaluate battery utilization and recycling from the perspectives of economic feasibility, environmental impact, technology, and safety. Battery sustainability is discussed with respect to life-cycle assessment and analyzed from the perspectives of strategic resources and economic demand. Finally, we propose a 4H strategy for battery recycling with the aims of high efficiency, high economic return, high environmental benefit, and high safety. New challenges and future prospects for battery sustainability are also highlighted.

Sustainable Recycling Technology for Li-Ion Batteries and Beyond: Challenges and Future Prospects.

The utilization of fossil fuels has enabled an unprecedented era of prosperity and advancement of well-being for human society. However, the associated increase in anthropogenic carbon dioxide (CO2) emissions can negatively affect global temperatures and ocean acidity. Moreover, fossil fuels are a limited resource and their depletion will ultimately force one to seek alternative carbon sources to maintain a sustainable economy. Converting CO2 into value-added chemicals and fuels, using renewable energy, is one of the promising approaches in this regard. Major advances in energy-efficient CO2 conversion can potentially alleviate CO2 emissions, reduce the dependence on nonrenewable resources, and minimize the environmental impacts from the portions of fossil fuels displaced. Methanol (CH3OH) is an important chemical feedstock and can be used as a fuel for internal combustion engines and fuel cells, as well as a platform molecule for the production of chemicals and fuels. As one of the promising approaches, thermocatalytic CO2 hydrogenation to CH3OH via heterogeneous catalysis has attracted great attention in the past decades. Major progress has been made in the development of various catalysts including metals, metal oxides, and intermetallic compounds. In addition, efforts are also put forth to define catalyst structures in nanoscale by taking advantage of nanostructured materials, which enables the tuning of the catalyst composition and modulation of surface structures and potentially endows more promising catalytic performance in comparison to the bulk materials prepared by traditional methods. Despite these achievements, significant challenges still exist in developing robust catalysts with good catalytic performance and long-term stability. In this review, we will provide a comprehensive overview of the recent advances in this area, especially focusing on structure-activity relationship, as well as the importance of combining catalytic measurements, in situ characterization, and theoretical studies in understanding reaction mechanisms and identifying key descriptors for designing improved catalysts.

Recent Advances in Carbon Dioxide Hydrogenation to Methanol via Heterogeneous Catalysis.

Recycling of spent lithium-ion batteries (LIBs) has attracted significant attention in recent years due to the increasing demand for corresponding critical metals/materials and growing pressure on the environmental impact of solid waste disposal. A range of investigations have been carried out for recycling spent LIBs to obtain either battery materials or individual compounds. For the effective recovery of materials to be enhanced, physical pretreatment is usually applied to obtain different streams of waste materials ensuring efficient separation for further processing. Subsequently, a metallurgical process is used to extract metals or separate impurities from a specific waste stream so that the recycled materials or compounds can be further prepared by incorporating principles of materials engineering. In this review, the current status of spent LIB recycling is summarized in light of the whole recycling process, especially focusing on the hydrometallurgy. In addition to understanding different hydromet...

A Critical Review and Analysis on the Recycling of Spent Lithium-Ion Batteries

Ever-growing global energy needs and environmental damage have motivated the pursuit of sustainable energy sources and storage technologies. As attractive energy storage technologies to integrate renewable resources and electric transportation, rechargeable batteries, including lead–acid, nickel–metal hydride, nickel–cadmium, and lithium-ion batteries, are undergoing unprecedented rapid development. However, the intrinsic toxicity of rechargeable batteries arising from their use of toxic materials is potentially environmentally hazardous. Additionally, the massive production of batteries consumes numerous resources, some of which are scarce. It is therefore essential to consider battery recycling when developing battery systems. Here, we provide a systematic overview of rechargeable battery recycling from a sustainable perspective. We present state-of-the-art fundamental research and industrial technologies related to battery recycling, with a special focus on lithium-ion battery recycling. We introduce the concept of sustainability through a discussion of the life-cycle assessment of battery recycling. Considering the forecasted trend of a massive number of retired power batteries from the forecasted surge in electric vehicles, their repurposing and reuse are considered from economic, technical, environmental, and market perspectives. New opportunities, challenges, and future prospects for battery recycling are then summarized. A reinterpreted 3R strategy entailing redesign, reuse, and recycling is recommended for the future development of battery recycling.

Toward sustainable and systematic recycling of spent rechargeable batteries

Recycling of lithium-ion batteries: Recent advances and perspectives

Hydrometallurgical recovery of metal values from sulfuric acid leaching liquor of spent lithium-ion batteries

Recovery of valuable metals from waste cathode materials of spent lithium-ion batteries using mild phosphoric acid.

In this study, a green process with prospective environmental and economic significance has been experimentally and theoretically established for the sustainable recovery of metals from spent lithium-ion batteries (LIBs). Three leaching systems were explored for the application of different biomass as reductants. According to leaching results, H3Cit (citric acid) and tea waste and H3Cit/H2O2 systems reveal similar leaching abilities (96% Co and 98% Li; 98% Co and 99% Li, respectively), while the H3Cit/Phytolacca Americana system shows inferior leaching performance (83% Co and 96% Li) under the optimized conditions. Tentative exploration of oxidation mechanism for different biomass indicates that potential reducing substances contained in biomass can be employed as efficient reductants during leaching. Then both metal ions and waste citric acid can be simultaneously recovered by selective precipitation. About 99% Co and 93% Li could be recovered as CoC2O4·2H2O and Li3PO4, and the recycled citric acid demon...

Tao Zhou

Papers

Hydrometallurgical recovery of metal values from sulfuric acid leaching liquor of spent lithium-ion batteries

Recovery of valuable metals from waste cathode materials of spent lithium-ion batteries using mild phosphoric acid.

Sustainable Recovery of Metals from Spent Lithium-Ion Batteries: A Green Process

An atom-economic process for the recovery of high value-added metals from spent lithium-ion batteries

Separation and recovery of metal values from leaching liquor of mixed-type of spent lithium-ion batteries