大学毕设论文__锂电池快速充电系统的设计.doc

锂电池快速充电系统的设计 摘要：充电技术是影响电池寿命和使用性能的重要因素，寻找有效的充电控制方法，有助于增强电池的使用性能，延长其使用寿命。本文分析了锂电池快速充电的方法。将整个充电过程分为预充电、恒流充电、恒压充电、涓流充电四个过程。根据此充电方法设计了一种以51单片机为控制核心的锂电池充电系统。整流电路得到的直流电一部分提供给单片机、ADC0808等芯片的供电电压，另一部分提供给电池充电。单片机根据A/D转换器得到的不同电压数值，输出控制不同的PWM波占空比，占空比改变后电池充电的电压值也相应发生变化。PROTUES仿真中，通过改变滑动变阻器的数值来模拟被充电电池两端电压的变化，三个八位数码管可以实时显示出此电压值的变化，在电压从低到高变化的过程中，可以从示波器看到四中不同的PWM波的占空比，以此来显示四个不同的充电过程。 关键词：快速充电，单片机，protues仿真 The design of Lithium battery quick charging system Abstract: The charge technology is an important factor that influence te life-span and performance of the batteries. So it is helpful to enhancing the performance and prolong the life-span of the batteries to find a effective charge control mode. This paper analyses the method of quick charge used for the lithium battery. This charging process can be divided into four steps ,which including the precharge、the constant current charge、the constant voltage charge、the trickle charge. The paper designs a kind of SCM-51 as control core of lithium battery charging system, according to this charging method. One part of the direct current got from the rectifier circuit supports the normal work the SCM、ADC0808. Another part of it used for charging the battery. The single-chip microcomputer can get different voltage dates depending on the A/D converter, so it can output different duty cycle of PWM, the charge voltage can be changed according. In the protues simulation, we can imitate the voltage variation of the charged battery by changing the slide rheostat value, three eight digital tube can be showed the real-time voltage change. In the process of voltage change from low to high,we can get four different duty cycle from the oscilloscope, so as to display the four different charging process. Keywords: quick charge，single-chip microcomputer，the protues simulation 目 录 1. 绪论 1 1.1 课题研究的背景及意义 1 1.2 本课题研究的基本内容和目的 1 2. 锂电池充电相关理论介绍 3 2.1 电池充电理论基础 3 2.2 快速充电方法的研究 5 2.3 脉冲快速充电原理 6 2.3.1 预充电 6 2.3.2 恒流充电 6 2.3.3 恒压充电 6 2.3.4 涓流充电 7 3. 锂电池快速充