Research On Quick Charging Strategy Of On-board Lithium Ion Battery

With the increasing shortage of petroleum energy and the increasingly serious pollution problem,fuel-fueled vehicles are gradually replaced by new energy vehicles.Due to the obvious advantages of zero emission,low decibel noise and energy saving,BatteryElectric vehicles have become the key development object of new energy vehicles.Due to the advantages of high energy ratio,Big output power and long service life,lithium Battery has become the preferred power source for Battery Electric Vehicle(BEV).As a core component of BEV,the power battery has a direct impact on the vehicle's running and safety performance through its management and control.With the development and maturity of BEV tri-electric technology,BEV has been developing rapidly and some problems need to be solved urgently.The main obstacles to the development of BEV include short battery range,slow charging and frequent power battery replacement.This paper adopts a low-cost and effective quick charging technology,taking into account the difficulty of research and development and the development trend of the industry.On the premise of ensuring battery life,improve charging speed and efficiency.Use quick charge to alleviate the electric car range low short board,when the deficiency of BEV,restore life through charging device for short periods of time,compared with the development of high energy density of power battery and improve the utilization efficiency of the energy of the battery pack these two kinds of methods,rapid charging technology scheme of research and development of low cost,shorter development cycle,at this stage are more likely to achieve on the basis of quick charge technology.The existing quick charging technology has a great impact on the power battery life when the charging rate is increased by high-power charging,resulting in frequent battery replacement of BEV,which increases the car owner's vehicle cost.In order to make up for these shortcomings,an optimization strategy of quick charging technology which can not only shorten the charging time of power battery,but also extend the service life of power battery is studied,which is of great significance to promote the development of BEV.For on-board lithium-ion battery charging ways exist rate is slow,low efficiency,large charging damage problem,this paper proposes a BEV intelligent optimization strategy of fast charging method,combining with BEV power battery charging features optimize the current charging methods,get quick charge optimization strategy for on-board lithium-ion batteries,which under the premise of extend the service life of power battery can shorten the charging time of BEV,and design the corresponding implementation plan.The research contents of this paper include the following four aspects:(1)First of all,analyses the basic working principle of lithium-ion batteries,charge characteristic factors and mas charging theory,and then studies the main fast charging method of lithium-ion batteries,summarizes the deficiency existing in the current fast charge method and the principle of optimization,the charging process must be according to real-time adjust the charging current lithium battery inside information to make sure that the battery will always work within the scope of the affordable,on the basis of improving the efficiency of charging speed and charging,and introduces the can reflect the internal information and dynamic information of the battery model.(2)The maximum charging current estimation model of lithium battery was established by using the algorithm of Extreme Learning Machine.The model fitted the functional relationship between the maximum charging current and other characteristic parameters through charging sample data.In the actual charging process,the maximum charging current of lithium battery is estimated in real time by monitoring the performance parameters of the battery,so that the battery is always within the range of the maximum charging current that can be borne,so as to extend the service life of the battery.(3)On the maximum charging current estimate model puts forward a method of intelligent control,fuzzy control algorithm was established using Takagi Sugeno-lithium battery charging control strategy can guarantee the power battery fast science in a variety of charging mode switch,allows charging parameters at the charging of lithium battery can bear range,maximum protection of lithium batteries,under the premise,to speed up the charge rate and improve the charging efficiency.(4)Designed the on-board lithium battery quick charging scheme of an optimization strategy based on lithium battery charging control algorithm is put forward by the corresponding software program and hardware circuit design,the related experiment was done on the experiment platform,compared with four more mainstream charging methods do,in the charging rate,charging efficiency,overcharge probability,cycle times,etc.,in this paper,the synthesis optimization strategy is superior to the other battery.