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.
Determination of crystal nucleus size of potassium chloride from ethanol solution caused by ultrasonic irradiation
Abstract The solubilities of electrolyte salts, such as sodium chloride (NaCl) and potassium chloride (KCl), are small in alcohol solution. As an application of such dilute solubility, nucleation phenomena were investigated by the dynamic laser scattering (DLS) method at different supersaturation degrees, prepared by different solubilities of KCl in aqueous ethanol solutions. The supersaturated solution of KCl was very stable, and therefore ultrasonic irradiation was utilized as a trigger of nucleation. The time-change of the sizes of fine KCl crystals was measured, and the nucleus size was obtained by extrapolating the size of the fine crystals to zero-time. The nucleus size of KCl was correlated by the modified Gibbs–Thomson equation as a function of supersaturation. It was found that the nucleus size tended to increase when supersaturation decreased, but three different curves for three different temperatures could be obtained. The modified Gibbs–Thomson equation represented the nucleus size at three different temperatures. The correlated “minimum supersaturation energy” parameters were converged to zero at the saturated temperature. The parameter “minimum supersaturation energy” could be interpreted as “ultrasonic effective energy” that could be defined as the received energy in the solution from ultrasonic irradiation.