Charging method and circuit for chargeable battery

Abstract

This invention relates to a charge method and a circuit for charge cells, in which, the method includes: controlling the output charged current to rise from zero to the peak value Im of the charge current in the specific time period t1 to t2 by adjusting the duty ratio of PWM control signal, and t1 and t2 are the beginning and ending time of the rising stage of the current, setting t the time as the X shaft, i the charge current as the Y shaft, keeping the peak value in the period of t2 to t3 to output charged current continuously, t3 is the ending time of the stable stage, the circuit includes a MCU process circuit and a current control circuit, and the MCU process circuit outputs PWM control signal of the monotony change of the duty ratio to the switch tube conversion circuit in the specific time period t1 to t2 and the output current of the current control conversion circuit rises to the peak value IM of the charge current.

Description

[technical field] [0001] The invention relates to a charging method and a charging circuit capable of prolonging the service life of a rechargeable battery. [Background technique] [0002] Because rechargeable batteries have the characteristics of being able to be used repeatedly, they have been widely used in portable electronic products, especially in mobile phones. Existing chargers, chargers and other products that charge rechargeable batteries, no matter what charging method is used, such as constant current, constant voltage, PWM multi-section constant charging, will have a great impact on the life of the rechargeable battery. Taking constant current and constant voltage as an example, when the rechargeable battery is over-discharged, the voltage of the rechargeable battery is very low. If the rechargeable battery is directly charged with constant current or constant voltage, it will seriously affect the performance of the rechargeable battery in all aspects, and then ...

AI Technical Summary

Problems solved by technology

[0004] 1. At the moment of starting to charge the rechargeable battery, the output of the charger is an inrush current or pulse current. Since the inrush current is suddenly added to the rechargeable battery in an instant, it is easy to cause damage to the rechargeable battery to a certain extent, thus shortening the charging time. battery life

[0005] 2. The inrush current generated at the moment of charging will also cause chronic damage to the contact points of the switching element, the charger and the rechargeable battery, and will also cause unnecessary troubles

[0006] 3. Although the sawtooth wave charging can buffer the impact current, it will make the charging power not be effectively used, resulting in waste of power, and will also affect the charging effect

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