A new high speed charge and high efficiency Li-Ion battery charger interface using pulse control technique

A new Li-Ion battery charger interface (BCI) using pulse control (PC) technique is designed and analyzed in this paper. Thanks to the use of PC technique, the main standards of the Li-Ion battery charger, i.e. fast charge, small surface area and high efficiency, are achieved. The proposed charger achieves full charge in forty-one minutes passing by the constant current (CC) charging mode which also included the start-up and the constant voltage mode (CV) charging mode. It designed, simulated and layouted which occupies a small size area 0.1 mm2 by using Taiwan Semiconductor Manufacturing Company 180 nm complementary metal oxide semi-conductor technology (TSMC 180 nm CMOS) technology in Cadence Virtuoso software. The battery voltage VBAT varies between 2.9 V to 4.35 V and the maximum battery current IBAT is 2.1 A in CC charging mode, according to a maximum input voltage VIN equal 5 V. The maximum charging efficiency reaches 98%.

Sliding-mode controller for a step up-down battery charger with a single current sensor

This paper proposes a battery charger solution based on the Zeta DC/DC converter to provide a general interface between batteries and microgrid direct current (DC) buses. This solution enables to interface batteries and DC buses with voltage conversion ratios lower, equal, and higher than one using the same components and without redesigning the control system, thus ensuring global stability. The converter controller is designed to require only the measurement of a single inductor current, instead of both inductors currents, without reducing the system flexibility and stability. The controller stability is demonstrated using the sliding-mode theory, and a design procedure for the parameters is developed to ensure a desired bus performance. Finally, simulations and experiments validate the performance of the proposed solution under realistic operation conditions.

Quantum batteries at the verge of a phase transition

Starting from the observation that the reduced state of a system strongly coupled to a bath is, in general, an athermal state, we introduce and study a cyclic battery-charger quantum device that is in thermal equilibrium, or in a ground state, during the charge storing stage. The cycle has four stages: the equilibrium storage stage is interrupted by disconnecting the battery from the charger, then work is extracted from the battery, and then the battery is reconnected with the charger; finally, the system is brought back to equilibrium. At no point during the cycle are the battery-charger correlations artificially erased. We study the case where the battery and charger together comprise a spin-1/2 Ising chain, and show that the main characteristics - the extracted energy and the thermodynamic efficiency - can be enhanced by operating the cycle close to the quantum phase transition point. When the battery is just a single spin, we find that the output work and efficiency show a scaling behavior at criticality and derive the corresponding critical exponents. Due to always present correlations between the battery and the charger, operations that are equivalent from the perspective of the battery can entail different energetic costs for switching the battery-charger coupling. This happens only when the coupling term does not commute with the battery's bare Hamiltonian, and we use this purely quantum leverage to further optimize the performance of the device.

Design and Control of a Battery Charger/Discharger Based on the Flyback Topology

Devices connected to microgrids require safe conditions during their connection, disconnection and operation. The required safety is achieved through the design and control of the converters that interface elements with the microgrid. Therefore, the design of both power and control stages of a battery charger/discharger based on a flyback is proposed in this paper. First, the structure of a battery charger/discharger is proposed, including the battery, the flyback, the DC bus, and the control scheme. Then, three models to represent the battery charger/discharger are developed in this work; a switched model, an averaged model, and a steady-state model, which are used to obtain the static and dynamic behavior of the system, and also to obtain the design equations. Based on those models, a sliding-mode controller is designed, which includes the adaptive calculation of one parameter. Subsequently, a procedure to select the flyback HFT, the output capacitor, and the Kv parameter based on operation requirements of the battery charger/discharger is presented in detail. Five tests developed in PSIM demonstrate the global stability of the system, the correct design of the circuit and controller parameters, the satisfactory regulation of the bus voltage, and the correct operation of the system for charge, discharge and stand-by conditions. Furthermore, a contrast with a classical PI structure confirms the performance of the proposed sliding-mode controller.