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A lithium–oxygen battery of double-gas-path structure and porous anode is presented in this work. Different from traditional structure battery, porous anode and the gas channel of anode side are used to provide argon gas for the battery. In order to protect the anode from corrosion of oxygen which penetrates from the cathode to the anode by dynamic gas-phase equilibrium. The improvement of the battery performance is attributed to the novel structure that can protect lithium metal from the corrosion of oxygen and it also reduces the growth of dendrite. The lithium–oxygen battery based on double-gas-path structure shows long cycle life (38 cycles), high discharge specific capacity (2510 mAh g−1) and specific energy density (7200 W h kg−1). More importantly, this work will also provide new ideas and methods for the research of other metal-air battery.

The dynamic response of proton exchange membrane fuel cells (PEMFCs) under mechanical vibration is an important criterion in the application to automotive systems. The effect of mechanical vibration on dynamic response was investigated on an automobile vibrating platform. The PEMFC voltage was acquired according to the current density change under a variety of amplitude, frequency and air stoichiometry. Furthermore, liquid water formation and transport were investigated under the mechanical vibration by employing a transparent PEMFC. The results show that a new steady-state of the voltage under vibration and no vibration take about 50s and 20s respectively after the current density step. The PEMFC dynamic performance was slightly improved under amplitude at 4 mm, compared to operation at no vibration. Also, the voltage fluctuation was detected under the vibration, the small droplets merged into larger droplets is due to the sudden vibration. These larger droplets interfere with the mass-transfer process in the gas channels.

Membrane Electrode Assembly (MEA) is a key component of direct methanol fuel cell. In order to improve the power generation performance of the MEA, it is necessary to reduce polarization losses. The cathode and anode activation polarization, proton exchange membrane ohmic polarization and gas diffusion layer mass transfer polarization were studied under different methanol concentration and operation temperature conditions respectively. A theoretical study of the various polarization fitting and distribution losses was conducted. The polarization distribution results indicated that the activation polarization of cathode and anode are the main over potential contribution and accounted for more than 80%. The ohmic resistance accounted for approximately 10%. By studying the distribution of polarization loss, we got a variety of distribution of polarization losses under different operating conditions, these results provide a theoretical basis for efficient ways to optimize the MEA.

A novel cellulose membrane used for isopropanol (IPA) dehydration was prepared by using N-methylmorpholine-N-oxide monohydrate (NMMO·H 2 O) as the solvent that can dissolve cellulose through a purely physical process. Scanning electron microscopy (SEM) images show that the prepared membrane had a homogeneously dense structure after natural drying. X-ray diffraction (XRD) and mechanical properties characterizations show that the prepared cellulose membrane owned much higher crystallization degree and better mechanical strength compared with traditional cellulose acetate (CA) or cellophane membranes coming from chemical process. The effects of operation conditions including feed concentration and operation temperature on pervaporation (PV) performance were investigated systemically. The results indicate that the permeation flux increased obviously with the increase of either water concentration in feed or operation temperature. Under the condition of 20 wt.% water-containing IPA feed and at 65 °C, a highest total flux of 349 g/m 2 h was achieved with a lowest water content in permeate of 99.50 wt.% (with a separation factor of 972) among all the tested conditions. Water content in permeate reached 99.97 wt.% (with a separation factor of 61,271) with a total flux of 13.4 g/m 2 h at the condition of 5 wt.% water in feed at 25 °C. Compared with other pure polymer membranes such as chitosan and poly(vinyl alcohol) (PVA), the prepared novel cellulose membranes exhibited acceptable fluxes and much higher separation factors. All these results demonstrate that cellulose membrane has great application potential in IPA dehydration process.