The Research Of On-line Monitoring The State Of Health And Residual Capacity Of The Nickel Metal Hydride Rechargeable Battery

With the development of The Times,because of the bad atmosphere environment and the shortage of energy,new energy battery is developing rapidly,green development has become the focus of the 13 th five Year Plan,new energy battery cars is the key areas of science and technology research,the nickel metal hydride rechargeable battery with high energy density,long cycle life,the characteristics of the green economy,in the daily life of digital electronic products,new energy automotive and aerospace and other fields has been widely applied.As the application of nickel metal hydride batteries more and more widely,for the battery management becomes more and more important,the battery if the lack of management,can lead to shorten the battery life,affect daily use,the state of health(SOH)of battery and residual capacity of judgment are important content of battery management.This paper mainly studied the judgmentmethod of the SOH and residual capacity of nickel metal hydride rechargeable battery,the correctness of the method is verified by experiment,and applied to engineering practice.This article first introduces several common rechargeable batteries as well as the advantages and disadvantages of various kinds of rechargeable batteries,and then introduces the development course and current situation of the development of nickel metal hydride rechargeable batteries,this paper discusses the structure and basic principle of nickel metal hydride rechargeable batteries,at the same time introduces the nickel metal hydride rechargeable battery charging and discharging characteristics,and the commonly used measuring method of nickel metal hydride rechargeable battery's SOH and residual capacity.In order to study the judgment method of the battery's SOH,this paper conducted a series of experiments,finding out the nickel metal hydride rechargeable batteries charged in the state of the relationship between the resistance and the battery SOH,and then through the MATLAB software for data fitting,by comparing several kinds of mathematical model,establish the Fourth order polynomial model to judge the battery degradation model,the maximum relative error is 4.7%,the model have small error range.For the judgment method of the nickel metal hydride rechargeable battery's residual capacity,this paper analyzes the advantages and disadvantages of several commonly used methods,combining with practical application,puts forward using Ampere-hour method with open circuit voltage method to determine the residual capacity of nickel metal hydride rechargeable battery,the maximum error of this method to judge nickel metal hydride rechargeable battery's residual capacity of is 5.2%,this method is more accurate.Finally,the paper established a complete nickel metal hydride rechargeable battery monitoring system,the system consists of the battery voltage monitoring,temperature monitoring,the monitoring of battery internal resistance,the monitoring of battery's SOH,the monitoring of battery's residual capacity,which can better applied to engineering practice.