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Conventional Al‐air batteries are not suitable as portable power devices due to their complicated water management and bulky system. To resolve this issue, the fiber paper‐ and cotton cloth‐based Al‐air batteries were proposed, which exploited the capillary force from the paper (FP) and cotton cloth (CC) to deliver the solutions and eliminated the external pump. The physical features of the FP and CC were gained including the surface morphologies, surface elementary analysis, liquid absorption and flow rates. CC owned larger liquid absorption and faster flow rate due to its hierarchically woven‐spun fiber structure, compared to the randomly oriented fibers of the FP, although the surface of the CC demonstrated lower O/C ratio than that of the FP. So, the performance of the CC‐based Al‐air battery was largely higher than that of the FP‐based battery. The performance of the CC‐based Al‐air battery was optimal at 1.0 M NaOH electrolyte and the anode‐to‐cathode surface area ratio of 1 : 4, with the peak power density of 14.95±0.28 mW cm−2, and the maximum current density of 36.61±0.54 mA cm−2. To apply the CC‐based Al‐air battery, the two‐battery pack connected in series was assembled to drive a timer and light 9 LEDs. [ABSTRACT FROM AUTHOR]

Fuel cell distributed drive electric tractor (FCDET) provided a novel pathway for the development of green agricultural machinery technology. However, FCDET faced problems such as low traction efficiency, short endurance, and high hydrogen consumption. Relevant studies have shown that reasonable and effective power allocation strategy can improve the efficiency and reduce the energy consumption of fuel cell systems. In this paper, a drive power allocation strategy based on adaptive multi-resolution analysis theory (AMRA) was proposed. The strategy could realize effective decoupling between various energy sources, reduce the problems of frequent start-stop and large power fluctuation for fuel cells. We started with an equivalent circuit model of the fuel cell system, a total efficiency solution model, an energy dissipation model, and a drive motor response model. The first-time reconstruction strategy was based on Tunable Q-factor Wavelet Transform (TQWT) to obtain a subsequence that responds to the oscillatory characteristics of the power signal. The second-time reconstruction strategy took the low-frequency subsequence through Variational Mode Decomposition (VMD) into a number of discrete sub-signals with special sparse properties. Meanwhile, the Sparrow Search Algorithm (SSA) was used to obtain the optimal combined values of the modal decomposition layers and the quadratic penalty factor in the VMD on real time. Finally, the second-time decomposed subsequences and sub-signals were reconstructed according to the frequency characteristics, and the reconstructed power signals were redistributed among the individual energy sources. In order to validate the proposed power allocation strategy, we used the ET504-H prototype as a research object. The power information of plowing and transportation operating conditions was collected in Mengjin test base of China YTO Group. The MATLAB/Simulink-PXI joint simulation platform was set up and the driving motor bench test was carried out in the New Energy Key Laboratory of Henan Province. The results show that the AMRA-based FCDET drive power allocation strategy can effectively improve the energy utilization of the fuel cell system and the economy of the whole tractor operating unit. Compared to the power-following strategy under plowing and transportation conditions, the average efficiency of the fuel cell system was improved by 8.3 % and 3.3 %, the equivalent hydrogen consumption was reduced by 35.6 % and 43.89 %, respectively. The average efficiency of the drive motor was improved by 2.06 % and 2.08 %, the total energy consumption was reduced by 3.73 % and 2.6 %, respectively. This study can provide a theoretical foundation and a novel technical approach for the development of FCDET control system. • The fuel cell system total efficiency solution model and the energy consumption model were established. • The AMRA based FCDET drive power allocation strategy is proposed. • A joint MATLAB/Simulink-PXI simulation platform was constructed for real-time validation. • The motor cooperative operation characteristics of the distributed drive system were tested. [ABSTRACT FROM AUTHOR]