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The rapid demand growth of lithium-ion batteries (LIBs) will inevitably lead to a shortage of related metal resources. Recycling valuable metals from spent LIB has become imperative. Here, we propose a non-hazardous, reliable, and efficacious process for in situ recovery of valuable components from spent LiNi0.5Co0.2Mn0.3O2 cathode. First, the cathode sheets pre-acquired by disassembly are thermally treated in CO2 atmosphere, and the intact Al foils with obvious metallic luster are recovered. The lithium component (Li2CO3) is preferentially dissolved in water, and the recovery efficiency reached 92.84 %. Meanwhile, the residues concentrated with Ni, Co, and Mn components are easily dissolved in sulfuric acid solution without any additional heat treatment, and no explosive gases are generated. Then, by comparing the thermal reduction characteristics of cathode materials under different atmospheres (Air, Ar, and H2/Ar), the mechanism of pyrolysis of cathode materials under CO2 atmosphere and the role of CO2 in the thermal reduction process are systematically studied. This work not only provides a novel method for the recycling of spent cathode materials but also guarantees the safety of related personnel and properties.

Funding Information: This research is supported by the National Natural Science Foundation of China ( 21773279 , 22075305 , 52061135110 ), Zhejiang Provincial Natural Science Foundation of China ( LD22E020003 ), the Key Research Program of the Chinese Academy of Sciences (ZDRW_CN_2020-1), and the Ningbo Science & Technology Innovation 2025 Major Project (2019B10050, 2019B10113, 2020Z024, 2020Z101, 2020Z025), and Key Laboratory of Bio-based Polymeric Materials of Zhejiang Province. Publisher Copyright: © 2023 High-nickel ternary cathode materials such as LiNi0.8Co0.1Mn0.1O2 (NCM811) are among the most promising cathode materials due to their high capacity and low cost. However, irreversible phase transition and interfacial side reactions over cycles remain critical concerns. In this paper, a two-step carbon coating process is developed to suppress the adverse phase transition and excessive side reactions at the electrode-electrolyte interface. Sucrose is melted firstly at mild temperature to be coated onto the particle surface, which is converted into carbon in situ at elevated temperature under oxygen atmosphere. Both the cyclic (96.7% capacity retention after 100 cycles at 1 C) and rate performance (130 mAh g−1 at 5 C) of the NCM811 cathode are effectively improved by the carbon coating treatment.

An all annealing-free solution-manufacturing is regarded as a technological advancement for the development of flexible organic solar cells (OSCs), which can prevent the distortion of plastic substrates, avoid destroying the active components of the devices, and simplify the device fabrication. Here, we report an efficient all annealing-free solution-processed flexible OSC integrated on a soft polyethylene (PE) substrate. The transparent anodes, hole-transport layers, active layers and electron-transport layers are solution-processed at room temperature without thermal annealing treatments. Thanks to both the as-developed gentle superacid doping and air-drying treatments at room temperature that enable a high-merit flexible anode on the soft PE substrates, the annealing-free flexible OSCs yield a high efficiency of 14.66% along with a high power-per-weight of 6.33 W g−1, which is close to that (15.73%) of thermally annealed rigid OSCs based on indium tin oxide anodes. Due to the mild annealing-free solution-processing and the soft PE substrates having an extremely low Young's modulus of only 0.2 GPa, the flexible OSCs maintain a high flexibility in a harsh bending test.

Gel polymer electrolytes (GPEs) have attracted ever-increasing attention in Li-ion batteries, due to their great thermal stability and excellent electrochemical performance. Here, a flexible poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP)-based GPE doped with an appropriate proportion of the PEO and SiO2 is developed through a universal immersion precipitation method. This porous PVDF-HFP-PEO-SiO2 GPE with high ionic conductivity and lithium-ion transference number (tLi+) can enhance the electrochemical performance of LiFePO4 cells, leading to superior rate capability and excellent cycling stability. Moreover, the PVDF-HFP-PEO-SiO2 GPE effectively inhibits the lithium dendrite growth, thereby improving the safety of Li-ion batteries. In view of the simplicity in using the gel polymer electrolyte, it is believed that this novel GPE can be used as a potential candidate for high-performance Li-ion batteries.

This paper describes the outcomes of a research study of a Robotic Tower Crane (RTC) which is part of a Digital Production Inventory Logistic Management System (DPILMS), that can be viewed as a complex system as it is required to deal with various inputs and perform different tasks in an unpredictable environment such as the construction field. The system has to work day and night, rain or shine under all-weather conditions. The RTC must sense the environment using multiple sensors. The proposed solution consists of various sensors capable of localizing the RTC in real-time, detect and track objects within the surroundings, and subsequently make decisions about how to react correctly within the appropriate time in the perceived environment, and several real-time subsystems. To achieve autonomous hoisting in an unpredictable environment, the real-time subsystems must interoperate with sensor processing, perception, localization, planning and control, processing an enormous amount of sensor data via a high complexity computation pipeline.

The cyclability of lithium-ion batteries (LIBs) is often affected by the components of the solid electrolyte interphase (SEI) layer which is generated from electrochemical decomposition of electrolyte. Here, lithium difluorophosphate (LiPO2F2) is studied in this work. When 1.6 wt% LiPO2F2 additive is incorporated into the reference electrolyte, the capacity retention of graphite/Li half-cell is increased from 82.53% to 98.04% and the capacity retention of LiCoO2/Li half-cell is increased from 89.60% to 97.53% after 160 cycles. Electrochemical impedance spectroscopy (EIS) indicates that the SEI layer containing LiPO2F2 can decrease the surface impedance of cells in the last stage cycle. In situ atomic force microscopy (AFM), DFT calculations and X-ray photoelectron spectroscopy (XPS) results show that LiPO2F2 is deposited on the surface of both LiCoO2 and graphite electrodes, which effectively protects the graphite anode and suppresses the degradation of the cathode during the long-term cycling of LIBs.

Electrochemical prelithiation is a facile, effective and extensively used method to improve the initial coulombic efficiency of SiO. However, much less research attention has been devoted to prelithiation effect on initial several cycles. Here, we introduce a new perspective to evaluate the prelithiation behaviors, which could understand in depth the electrochemical prelithiation behaviors and their effects on the following two cycles. Then X-ray photoelectron spectroscopy was further performed to pinpoint the reaction products. It has been found that the quantity of irreversible Li4SiO4, Li2O and SEI (Li2CO3 and LiF) and reversible LixSi are increasing as the prelithiation time extending. When the prelithiation time extending over 20 min, only alloy reaction of Si has been revealed. The regeneration of SEI discloses at least 7% capacity loss in the first cycle which depends on the prelithiated time. However, the reformation of SEI in the second cycles reveals 3% capacity loss. Because the coulombic efficiencies are independent on prelithiated time in the second cycle which indicates only one discharge/charge cycle is enough to form integrated SEI and adequate irreversible Li4SiO4 and Li2O except part of unreactive SiOx.

Anisotropic disorder along the c-axis results from static disorder.

Titanium dioxide of bronze phase (TiO2(B)) has attracted considerable attention as a promising alternative lithium/sodium-ion battery anode due to its excellent operation safety, good reversible capacity, and environmental friendliness. However, several intrinsic critical drawbacks, including moderate electrochemical kinetics and unsatisfactory long cyclic stability, significantly limit its practical applications. It is crucial to develop reliable strategies to resolve these issues to advance the TiO2(B) based materials into practical applications in lithium/sodium-ion batteries. In this review, both the theoretical and experimental investigations on the TiO2(B) based materials over the last few decades are chronically elaborated. Insights on the general and detailed evolution trends of the research on TiO2(B) anodes are provided. The review also points to future directions for the TiO2(B) anode research to advance the practical application of TiO2(B) anodes.