Study on closed loop charging strategy of battery based on Maas's law
In the process of battery charging, the influence of different charging methods on battery life is different. Traditional charging methods such as constant voltage charging, constant current charge, two phase charge, or three phase charge, these methods to a certain extent accelerate the aging of the battery. In this paper, based on the theory of Maas best charge curve and closed-loop control, a charging strategy is designed. The experimental results show that the designed charging strategy has a substantial improvement in the aspect of extending battery life and safety protection.
Novel charge/discharge method for lead acid battery by high-pressure crystallization
Abstract The electrical charging and discharging of a battery involves the crystallization of electrolytes or metal oxides on both electrodes. Crystallization technology that can control nucleation, growth, and distribution of solute crystals might be effective for improving battery properties. We performed charge/discharge cycling of a lead acid battery under high pressure. The charging efficiency at high pressure was compared with that at atmospheric pressure. Charging efficiency at high pressure was found to be higher than that at atmospheric pressure under a high charging current. Observation of the positive electrode by scanning electron microscopy revealed that high pressure caused the crystals on the electrode to become extremely fine.
New Li-Ion Battery Charger Based on Charge-Pump Techniques
This paper presents a new Li-ion battery charger using charge-pump techniques. It has small chip size and simple structure. Besides, the proposed charger provides basic functions with voltage and current detecting, end-of-charge detecting and automatic charging speed control. The charger is operated in mixed method and supported from trickle/large constant-current mode to constant-voltage mode with different charging rates. This charger is implemented in TSMC 0.35 mum CMOS process with 5 V power supply. Its output voltage is over or equal to 4.2 V and maximum charging current reaches 700 mA. It has 837 mW chip power dissipation and 67.89% power efficiency and chip area is 1.455times1.348 mm2 only