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Ni−rich cathodes are hopeful materials for advanced lithium−ion batteries (LIBs) due to high capacity. Nonetheless, the chemical crosstalk triggered by reactive oxygen (O*) represents a critical factor in thermal runaway (TR). Currently, there are few effective means to prevent this parasitic reaction. Here, inspired by the O* scavenging effect of β−carotene in living organisms, it is innovatively identified that β−carotene can impede TR by restraining the escape of O* during the thermal decomposition of nickel−rich cathodes. Using LiNi0.6Co0.2Mn0.2O2 as model and extending to higher nickel content cathodes (LiNi0.8Co0.1Mn0.1O2, LiNi0.9Co0.05Mn0.05O2), it is demonstrated that β−carotene can undergo an in situ oxygen copolymerization reaction to trapping O*, thereby attenuating chemical crosstalk. Additionally, the generated oxygen copolymer can also adjust band center of the O 2p orbitals of delithiated cathode, alleviating the charge compensation behavior of oxygen anions, and thus delaying the phase transition of charged LiNi0.8Co0.1Mn0.1O2. As a result, the TR trigger temperature of NCM811∣Graphite pouch cell is increased from 131.0 to 195.0 °C and maximum temperature is reduced from 657.8 to 412.4 °C. This work introduces a new and simple strategy for designing functional additives to block TR, offering a promising avenue for advancing the safety of LIBs. [ABSTRACT FROM AUTHOR]

In order to achieve the exoskeleton steady,reliable and long operation. Taking exoskeleton principle prototype hydraulic power unit as research object,using the method of Fourier series to establish the exoskeleton kinematics model,analyzing the characteristics of exoskeleton hydraulic system to get hydraulic power unit required heat dissipated power. Establish model of the exoskeleton hydraulic power unit and simulation the thermal of exoskeleton hydraulic power unit in ANSYS to analyze the exoskeleton heat dissipated power and temperature field,bring up an appropriate solving scheme.

Summed up six typical working conditions of the rail track replacement device. Its working load is calculated by three kinds of method. And the theoretical model of telescopic rail track replacement car for work equipment is established.Accelerating factor and inertia weight Improved PSO,and adding the chaos algorithm optimize five main parameters of hexagonal cross-section telescopic boom. The optimization results show,telescopic quality has reduced by 29. 6%; overall centroid position has down; counterweight with telescopic functionis smaller; the balance of front and rear axle bogie track replacement has achieved; In other railcars improved machine stability.

Fluorinated solvents emerge as a promising strategy to improve performance of lithium metal batteries (LMBs). However, most of them are prone to produce corrosive HF and deteriorate electrode interface, inducing cathode‐to‐anode detrimental crossover of transition metal‐ions. Here, fluorinated aromatic hydrocarbons in dimethyl carbonate (DMC)‐based diluted highly concentrated electrolyte (DHCE) are employed to juggle formation of HF and LiF, enabling stable cycling of high‐voltage LiNi0.7Co0.1Mn0.2O2 (NCM712) and LiCoO2 (LCO). The nature of aromatics in this carbonate‐based DHCE makes them difficult to undergo β‐hydrogen assisted defluorination, evidencing by the high energy barrier and high bond energy of β‐sites hydrogen. The advanced DHCE restrains HF formation but strengthens LiF formation, which not only suppresses impedance growth, transition‐metal dissolution, and stress crack on the cathode, but achieves highly reversible Li stripping/plating with an outstanding average Coulombic efficiency up to 99.3%. The Li||NCM712 cell and Li||LCO cell both exhibits superior cycling stability at high operation voltage. Even under stringent conditions, the 4.4 V Li||NCM712 full battery retains >95% of the initial capacity over 100 cycles, advancing practical high‐voltage LMBs. This study designs an efficient electrolyte that generates robust electrode/electrolyte interphases and restrains by‐products formation spontaneously, thus shedding new light on electrolyte toward applicable LMBs. [ABSTRACT FROM AUTHOR]