Abstract-An actively controlled battery/ultracapacitor hybrid has broad applications in pulse-operated power systems. A converter is used to actively control the power flow from a battery, to couple the battery to an ultracapacitor for power enhancement, and to deliver the power to a load efficiently. The experimental and simulation results show that the hybrid can achieve much greater specific power while reducing battery current and its internal loss. A specific example of the hybrid built from two size 18650 lithium-ion cells and two 100-F ultracapacitors achieved a peak power of 132 W which is a three-times improvement in peak power compared to the passive hybrid power source (hybrid without a converter), and a seven times improvement as compared to the lithium-ion cells alone. The design presented here can be scaled to larger or smaller power capacities for a variety of applications.Index Terms-Hybrid power source, lithium-ion battery, peak power enhancement, power converter, ultracapacitor.

A novel metal−organic framework (MOF), formulated as [Cd 2 (TTVTC)Cl 2 (H 2 O) 3 ]•2H 2 O (1), was synthesized from a tetracarboxylate ligand ([TTVTC] 2− ) functionalized with the thiazolothiazole extended viologen (TTV 2+ ) fluorophore. The MOF features three-dimensional (10,3)-d frameworks with 6-fold interpenetration. The MOF exhibits reversible photochromism, due to photoinduced electron transfer from carboxylate to TTV 2+ . The photoactivity benefits from the electron donor−acceptor contacts enabled by mutual interpenetration of the frameworks. This is the first demonstration of photochromism in TTV 2+ derivatives. In addition, the fluorescence arising from the TTV 2+ fluorophore can be reversibly modulated during the photochromic process. The work demonstrates the great potential of extended viologen based ligands in the construction of MOFs with dual photomodulable optical properties, which could find future applications in photoelectronics.

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Abstract-Hybrid systems composed of fuel cells and batteries combine the high energy density of fuel cells with the high power density of batteries. A dc/dc power converter is placed between the fuel cell and the battery to balance the power flow between them and greatly increase the peak output power of the hybrid. This paper presents an adaptive control strategy for active power sharing in the hybrid power source. This control strategy can adjust the output current setpoint of the fuel cell according to the state-of-charge (or voltage) of the battery, and is applicable in two topologies of active fuel cell/battery hybrids. The control strategy is implemented in Simulink and then tested under arbitrary load conditions through simulation and experiments. Simulation and experimental results show that the adaptive control strategy is able to adjust the fuel cell output current to adapt to the charge state of the battery, and appropriately distribute the electrical power between the fuel cell and the battery. Experiments demonstrate the generality of the adaptive control strategy.Index Terms-Active power sharing, adaptive control strategy, battery, fuel cell, hybrid power sources, power converter.

We present here a complete dynamic model of a lithium ion battery that is suitable for virtual-prototyping of portable battery-powered systems. The model accounts for nonlinear equilibrium potentials, rate-and temperature-dependencies, thermal effects and response to transient power demand. The model is based on publicly available data such as the manufacturers' data sheets. The Sony US18650 is used as an example. The model output agrees both with manufacturer's data and with experimental results. The model can be easily modified to fit data from different batteries and can be extended for wide dynamic ranges of different temperatures and current rates.

We present a one-step effective synthetic strategy for excellent thermally and mechanically reinforced pseudo-interpenetrating poly(propylene carbonate) networks (PIPPCNs) by CO 2 /propylene oxide/pyromellitic dianhydride terpolymerization. This strategy will enable PPC to be smoothly processed by heat without decomposition and to be used in a wider range of applications such as packaging, commodity and agriculture films.