Abstract

The advantage of the EVs is the mechanical simplicity of the drivetrain. For

example, an EV drive train can convert energy stores into vehicle motion, just like a
conventional  vehicle,  and  it  can  also  reverse  direction  and  convert  vehicle  motion
back  into  energy  stores  through  regeneration  barking,  which  means  that  theirs
energy/work  loop  is  inherent  bi-directional.  Besides,  moving  parts  of  the  electric
motor in the EVs consist primarily of the armature (DC motors) or rotor (AC motors)
and  bearings,  a  relatively  simple  and  far  more  efficient  machine.  other  advantages
include  electric  motor  torque  much  more  suited  to  the  torque  demand  curve  of  a
vehicle. EV drive train often needs only one gear ratio other than two or more. More-
over, a reverse gear is unnecessary because the rotational direction of the motor itself
can be reversed simply by reversing the electrical in-put polarity.

Lithium iron battery pack with the joint design of hardware andsoftware system

debug  and  test  on  electric  vehicles.  The  results  show  that  theintroduction   of   the
battery   management   system   is   reliable,   economianti-interference  ability.  This
battery  management  system  can  achieve:  the  Collection  of  battery  voltage,  current,
temperature; the calculation of the remaining capacity and battery status judgments;
real-time display, fault alarmrelated functions..

The system consists of a data acquisition module, powercalculation module,

protection module. System uses Freescale MC9SO8D216 CPLJ, throug the immediate
acquisition module collects the battery voltage, current, and temperature, prevent the
battery from aver-voltage, aver temperature, over-current, make battery more secure,
continuingprocess in effect, extend battery life span, increase the electric bicycle
security in motion.

This design of lithium battery management system's hardware reliability,

economy, anti-interference ability. the estimated on remaining capacity SaC is
accurate through practice,balanced can basically meet the requirements.
Key words：SOC；

Management system； Energy

摘

要