Fast Charging Method For Electric Vehicle Charging Stations

① Pulse charging method not only follows the inherent charging acceptance rate of batteries, but also improves the charging acceptance rate of electric vehicle batteries, breaking the limitations of the battery index charging acceptance curve. This is also a new development in battery charging theory.
② 2REFLEXTM fast charging method is a patented technology in the United States, which mainly targets nickel cadmium batteries for charging. Due to its adoption of a new charging method that solves the memory effect of nickel cadmium batteries, it greatly reduces the fast charging time of the battery. The charging method and detection method of charging status for lead-acid batteries are significantly different from nickel cadmium batteries, but they can borrow from each other. One working cycle of the REFLEXTM charging method includes three stages: forward charging pulse, reverse instantaneous discharge pulse, and stop charging maintenance.
③ The variable current intermittent charging method is based on constant current charging and pulse charging, as shown in Figure 7. Its characteristic is to change the constant current charging section to a limited voltage variable current intermittent charging section. In the early stages of charging, the method of variable current intermittent charging is adopted to ensure that the charging current is increased and the majority of the charging capacity is obtained. In the later stage of charging, a constant voltage charging section is used to obtain the overcharge amount and restore the battery to a fully charged state. By intermittently stopping charging, the oxygen and hydrogen produced by the chemical reaction of the battery have time to recombine and be absorbed, naturally eliminating concentration polarization and Ohmic polarization, thereby reducing the internal pressure of the battery and enabling the next round of constant current charging to proceed more smoothly, allowing the battery to absorb more electricity.
④ The variable voltage intermittent charging method has been proposed based on the variable current intermittent charging method, as shown in Figure 8. The difference from the variable current intermittent charging method is that the first stage is not intermittent constant current, but intermittent constant voltage. At each constant voltage charging stage, due to the constant voltage charging, the charging current naturally decreases exponentially, which is in line with the characteristic that the acceptable rate of battery current gradually decreases with the progress of charging.