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FLAMINGO is developing a service to facilitate for high accuracy positioning in smartphones and IOT devices. Currently, smartphones can only achieve accuracies of several meters at best, and IOT systems desire low power, connectivity, and a highly accurate location. FLAMINGO will deliver a service that targets sub-meter accuracies in both client- and server-side positioning scenarios. Through this, a new suite of location-based applications will be enabled, that were before infeasible, as well as enhancing existing location products. Substantial server infrastructure is developed to remove user GNSS knowledge needs, where an Application Program Interface (API) is provided to simplify integration. Modified PPP and RTK processing procedures are used to provide the high accuracy positioning.

Fuel cells (FCs) are electrochemical devices, which produce electricity (and sometimes heat) without any intermediate step. These units are known for their high total and electrical efficiency, low emission levels, silent operations and scalability. There are several types of fuel cells, which operate at different temperatures, require different fuels and levels of servicing. Some of FC types can be also used for mobile applications – e.g. Unmanned Aerial Vehicles (UAV). Auxiliary Power Units (APU) or main power source is for FC vehicles. Recently, there has been a growing interest in research on mobile applications of fuel cells, both for civilian and military purposes. Several commercial companies focusing on fuel cells have been established, performing their R&D activities in their niches. In addition, there are special dedicated research funds for fuel cell and hydrogen research in countries such as USA, China, Japan, France and Germany. Moreover, the European Commission devotes funds for the fuel cell activities through a public-private partnership. This trend is predicted to continue in coming years, as fuel cells become smaller, easier and cheaper to operate and manufacture. This paper focuses on the current “state of the art” in fuel cell research, both commercial and governmental/military. In addition, some examples of mobile applications, focusing on fuel cell vehicles, spacecrafts and UAVs are presented, together with a predicted outcome for following years.

Two types of micro-tubular hollow fiber SOFCs (MT-HF-SOFCs) were prepared using phase inversion and sintering; electrolyte-supported, based on highly asymmetric Ce0.9Gd0.1O1.95(CGO) HFs and anode-supported based on co-extruded NiO-CGO(CGO)/CGO HFs. Electroless plating was used to deposit Ni onto the inner surfaces of the electrolyte-supported MT-HF-SOFCs to form Ni-CGO anodes. LSCF-CGO cathodes were deposited on the outer surface of both these MT-HF-SOFCs before their electrochemical performances were compared at similar operating conditions. The performance of the anode-supported MT-HF-SOFCs which delivered ca. 480 mW cm–2 at 600 °C was superior to the electrolyte-supported MT-HF-SOFCs which delivered ca. six times lower power. The contribution of ohmic and electrode polarization losses of both FCs was investigated using electrochemical impedance spectroscopy. The electrolyte-supported MT-HF-SOFCs had significantly higher ohmic and electrode polarization ASR values; this has been attributed to the thicker electrolyte and the difficulties associated with forming quality anodes inside the small (

A co-extrusion technique was employed to fabricate a novel dual layer NiO/NiO-YSZ hollow fiber (HF) precursor which was then co-sintered at 1,400 °C and reduced at 700 °C to form, respectively, a meshed porous inner Ni current collector and outer Ni-YSZ anode layers for SOFC applications. The inner thin and highly porous “mesh-like” pure Ni layer of approximately 50 μm in thickness functions as a current collector in micro-tubular solid oxide fuel cell (SOFC), aiming at highly efficient current collection with low fuel diffusion resistance, while the thicker outer Ni-YSZ layer of 260 μm acts as an anode, providing also major mechanical strength to the dual-layer HF. Achieved morphology consisted of short finger-like voids originating from the inner lumen of the HF, and a sponge-like structure filling most of the Ni-YSZ anode layer, which is considered to be suitable macrostructure for anode SOFC system. The electrical conductivity of the meshed porous inner Ni layer is measured to be 77.5 × 105 S m–1. This result is significantly higher than previous reported results on single layer Ni-YSZ HFs, which performs not only as a catalyst for the oxidation reaction, but also as a current collector. These results highlight the advantages of this novel dual-layer HF design as a new and highly efficient way of collecting current from the lumen of micro-tubular SOFC.

As an effective effort in improving the performance of electrolyte/anode dual-layer hollow fibres (HFs) for micro-tubular solid oxide fuel cell (SOFC), high quality dual-layer HFs with controllable electrolyte layer thickness have been developed in this study by adjusting fabrication parameters of a single-step co-extrusion and co-sintering process. Uniform and defect-free outer electrolyte layer from 70 to 10 μm can be achieved when the extrusion rate is reduced from 5 to 0.5 ml min −1 . Although the bending strength and the gas-tightness properties are reduced slightly with the decrease in electrolyte layer thickness, significant improvement in power output of the cell is achieved. Power density as high as 1.11 W cm −2 is obtained on the cell with the electrolyte layer of 10 μm in thickness, which is 114% higher than the one with an electrolyte layer of 65 μm.

A combined phase inversion and sintering technique was used to fabricate highly asymmetric yttria-stabilized zirconia (YSZ) hollow fibers with a 1.9 mm external diameter and 210 μm total wall thick...

NiO–yttria stabilised zirconia (YSZ) hollow fibres with varying NiO content and a desired microstructure were prepared using a phase inversion technique and sintering. By controlling the fabrication parameters, microstructures with predominately finger-like pores near the inner and outer surfaces and a denser central layer with sponge-like pores were produced, for use as substrates for anode-supported hollow fibre solid oxide fuel cells (HF-SOFC). The NiO–YSZ fibres were reduced to Ni–YSZ at 250–700 °C in hydrogen flowing at 20 cm 3 min − 1 to produce Ni–YSZ hollow fibres, the mechanical and electrical properties of which were determined subsequently, reduction to Ni being verified by X-ray diffraction. The effects of NiO concentration and sintering temperature of the fibre precursors on the conductivity, strength and porosity of the reduced hollow fibres were investigated to assess their suitability for use as anode substrates. As expected, increasing Ni concentration increased electrical conductivities and decreased mechanical strength. Sintering temperature had a critical effect in producing axially conductive hollow fibres of sufficient mechanical strength for use as SOFC anodes. The hollow fibres retained their initial microstructure through the reduction process, though ca. 41% volume contraction is predicted on reduction of NiO to Ni, producing increased porosity in the reduced fibres. The mean porosity of the Ni–YSZ hollow fibres was ca. 60% and ca. 40% after sintered at 1250 °C and 1400 °C, respectively. The mean pore sizes for all the fibres after reduction varied between ca. 0.3 and 1 µm. The hollow fibres produced with 60% NiO, of length ca. 300 mm, electrical conductivities of ca. (1–2.25) × 10 5 S m − 1 and a porosity of ca. 43% are being used currently to construct and test the electrical behaviour of an anode-supported HF-SOFC.

Nickel anodes were deposited on hollow fibre yttria-stabilised zirconia (YSZ) electrolyte substrates for use in solid oxide fuel cells (SOFCs). The hollow fibres are characterised by porous external and internal surfaces supported by a central gas-tight layer (300 μm total wall thickness and 1.6 mm external diameter). The YSZ hollow fibres were prepared by a phase inversion technique followed by high temperature sintering in the range 1200 to 1400 °C. Ni anodes were deposited on the internal surface by electroless plating involving an initial catalyst deposition step with PdCl2 followed by Ni plating (with a NiSO4, NaH2PO2 and sodium succinate based solution at 70 °C). Fabrication and nickel deposition parameters (nature of solvents, air gap, temperature, electroless bath composition) and heat treatments in oxidising/reducing environments were investigated in order to improve anode and electrolyte microstructure and fuel cell performance. A parallel study of the effect of YSZ sintering temperature, which influences electrolyte porosity, on electrolyte/anode microstructure was performed on mainly dense discs (2.3 mm thick and 15 mm diameter). Complete cells were tested with both disc and hollow fibre design after a La0.2Sr0.8Co0.8Fe0.2O3−δ (LSCF) cathode was deposited by slurry coating and co-fired at 1200 °C. Anodes prepared by Ni electroless plating on YSZ electrolytes (discs and hollow fibres) sintered at lower temperature (1000–1200 °C) benefited from a greater Ni penetration compared to electrolytes sintered at 1400 °C. Further increases in anode porosity and performance were achieved by anode oxidation in air at 1200–1400 °C, followed by reduction in H2 at 800 °C.

A co-extrusion technique was employed to fabricate a dual layer NiO/NiO-YSZ hollow fibre precursor which was then co-sintered at 1400 °C and reduced at 700 °C to form, respectively, a meshed porous inner Ni current collector and outer Ni-YSZ anode layers for SOFC applications. Achieved morphology consisted of short finger-like voids originating from the inner bore of the hollow fibre, and a sponge-like structure filling most of the Ni-YSZ anode layer, which is considered to be suitable macrostructure for anode SOFC system. The electrical conductivity of the meshed porous inner Ni layer was measured to be 77.5×105 S m−1. This result is significantly higher than previous reported results on single layer Ni-YSZ hollow fibres, which besides performing a catalyst function for the oxidation reaction also act as a current collector. These results highlight the advantages of this dual-layer hollow fibre design especially in developing a new and highly efficient way in current collection for micro-tubular SOFC. Keywords: SOFC, Phase inversion, Sintering, Dual layer, YSZ, Hollow fibre

DOI of original article: 10.1016/j.ssi.2008.12.038. ⁎ Corresponding author. E-mail address: i.metcalfe@newcastle.ac.uk (I.S. Metcalfe). Fig. 3. Ni concentration detected by EDS across Pellet A and Fibre A cross sections immediately after electroless plating (dipping method). Pellet data refers to our previous work [15]. Fig. 4. Ni concentration detected by EDS across Pellet B and Fibre B cross sections immediately after electroless plating (dipping method). Pellet data refers to our previous work [15].