The Research And Design Of A Smart Battery Management System

With the progressive consumption of fossil energy,as well as the encouragement of national policy,many companies develop new energy one after another,as a substitute for consuming energy.Lithium-ion battery,as an excellent energy storage device,have played an irreplaceable role in the development of new energy.But in order to get a higher voltage and power,large amounts of single lithium battery are required to connect by series connection.After the lithium battery pack come into being,however,the battery life will seriously shorten due to the inconsistency of the single cells.And in the process of utilizing lithium-ion battery,it tends to occur overcharge,over-discharge,overcurrent and other problems,even burning,explosion and other malignant safety accident.These problems not only hamper the application development of lithium batteries,but also threatened the users' security of lives and properties,so in order to guarantee the effective use of lithium battery pack safely and reliably,corresponding battery management must be adopted for lithium battery pack.At present,portable devices and parts of electric bicycles in the market are mostly used in series lithium battery pack,and corresponding battery management module of lithium battery pack in devices mostly is integrated circuit constituted by lithium battery protection microchips,which can only provide basic protection for lithium battery pack.The intelligent battery management system designed in this paper,can able to general manage the use of series lithium battery pack,and address current integrated protection circuit's problems,including high cost,difficult extension and single function.This paper focuses on lithium battery voltage and current monitoring technology,overcharging management technology and equilibrium management technique.And in order to resolve the current lithium battery's problems,a complex and inflexible equilibrium strategy,using fuzzy-PID control algorithm to design a fine controlled equilibrium strategy.And to design a PIC16F1526 SCM-centered(Single Chip Microcomputer)intelligent battery management system according to technical research results.This system mainly realize charging and discharging real-time battery management of series lithium battery pack,to prevent overcharge,overcurrent,overdischarge and unequalizing charge in the lithium battery pack.Compared to the integrated protection circuit of traditional lithium battery,the entire system is scalable,low cost,high intelligent degree and long service life and other characteristics and practical value is very high.Firstly,this paper brings research background,research status,as well as the real significance of the selected topic.Then to study and analyze technical difficulties of battery management system and to propose the corresponding technical solution according to the research results.Next,to present an overall design scheme of the system according to research results and to design the hardware circuit of intelligent battery management system,including the current and voltage detection circuit,single chip processing,control circuits,equalizing charging control circuit and switching power supply circuit.And then write the software program of intelligent battery management system according to the hardware circuit.Finally,to conduct system verification experiment and work summary,to do the practical application test experiment,system relative error analysis of obtained experimental data and to verify the practicability and accuracy of the system.