Energy Recovery Battery Formation Detection System

Aiming at the problem of how to realize energy recovery in the process of lithium battery formation,a two-way lithium battery formation detection system with energy recovery function is designed.The system includes adjustable constant voltage and current charging function,bidirectional energy recovery function,over-voltage and over-current protection function.The main contents of this paper are as follows:1.Study on charging method of lithium batteiy.It includes four charging methods:constant voltage charging method,constant curnent charging method.pulse charging method and constant voltage and constant current charging method.By comparing the advantages and disadvantages of four charging methods for lithium batteries,it is determined that the charging scheme used in this system is constant current charging before constant voltage charging.2.Study on the scheme of constant voltage and current.Constant voltage scheme is used to build voltage stabilization circuit based on IC chip to realize the function of boost and buck.XL6019 is used as boost and buck chip.By comparing the comparator with the constant cxirrent value,the constant current output is realized through the hardware closed-loop voltage compensation.3.Study on voltage regulation scheme.The adjustable DC voltage is generated by adjusting the duty cycle of PWM wave,and the sampling voltage of sampling foot is controlled to adjust the output voltage.4.Study on energy recovery scheme.A non-isolated bidirectional DCDC c:ircuit is used to control the bidirectional flow of energy through the on-ofif of the MOS transistor controlled by the upper computer.At the same time,when the lithixum battery is discharged,the energy is recovered to the energy storage system and used to power the lower charging module to achieve energy recovery.Finally,the lithium battery of 18650 type was tested for charging and discharging.The test results show that the system can achieve constant voltage output or constant current output,and the charging voltage and current value can be adjusted by the host computer.The adjustment error is less than 1%,and the energy recovery efficiency is between 30%and 40%.In the case of over-charging and over-discharging,the purpose of protecting lithium battery can be achieved by stopping IC chip operation.The system can meet the charging requirements for different types of lithium batteries and has good application prospects.