Battery management circuit, device to be charged, and power management method

Patent metadata

Field	Value
Publication number	US-11322949-B2
Application number	US-201816206117-A
Country	US
Kind code	B2
Filing date	Nov 30, 2018
Priority date	Oct 12, 2016
Publication date	May 3, 2022
Grant date	May 3, 2022

Abstract

Battery management circuits include a first charging channel, a Cuk circuit, and a communication control circuit. A battery is charged through the first charging channel based on charging voltage and/or charging current provided by a power supply device. The battery includes a first cell and a second cell coupled in series. The communication control circuit is configured to communicate with the power supply device, to make magnitude of the charging voltage and/or charging current provided by the power supply device match a present charging stage of the battery, and the communication control circuit is further configured to send a drive signal to the Cuk circuit to drive the Cuk circuit to work, to make energy of the first cell and the second cell be transferred through the Cuk circuit to balance voltage of the first cell and voltage of the second cell.

First claim

What is claimed is:

1. A battery management circuit, comprising:
a first charging channel, a Cuk circuit, and a communication control circuit, wherein
at least one of charging voltage and charging current is received from a power supply device and applied directly to a battery for charging through the first charging channel, the battery comprising a first cell and a second cell coupled in series, wherein the at least one of the charging voltage and the charging current received from the power supply device is applied directly to the battery without being converted; and
the communication control circuit is configured to:
communicate with the power supply device to make a magnitude of at least one of the charging voltage and the charging current received from the power supply device match a present charging stage of the battery, when the power supply device charges the battery through the first charging channel, wherein the present charging stage of the battery is any one of a trickle charging stage, a constant-current charging stage, and a constant-voltage charging stage; and
send a drive signal to the Cuk circuit to drive the Cuk circuit to work, to make energy of the first cell and the second cell be transferred through the Cuk circuit to balance voltage of the first cell and voltage of the second cell, when the voltage of the first cell and the voltage of second cell are unbalanced.

2. The battery management circuit of claim 1 , wherein the communication control circuit is further configured to acquire at least one of present power and present voltage of the first cell, and at least one of present power and present voltage of the second cell, before the drive signal is sent to the Cuk circuit to drive the Cuk circuit to work, and wherein
the communication control circuit configured to send the drive signal to the Cuk circuit to drive the Cuk circuit to work is configured to:
send the drive signal to the Cuk circuit to drive the Cuk circuit to work when a difference between at least one of the present power and the present voltage of the first cell, and at least one of the present power and the present voltage of the second cell is greater than a preset threshold value.

3. The battery management circuit of claim 1 , wherein the communication control circuit is further configured to adjust duty cycle of the drive signal to adjust current in the Cuk circuit, during working of the Cuk circuit.

4. The battery management circuit of claim 3 , further comprising a current detecting circuit configured to detect the current in the Cuk circuit, wherein the communication control circuit configured to adjust the duty cycle of the drive signal, to adjust the current of the Cuk circuit is configured to:
determine a target value of the current in the Cuk circuit, according to the difference between at least one of the present power and the present voltage of the first cell and at least one of the present power and the present voltage of the second cell, and
adjust the duty cycle of the drive signal to make the current in the Cuk circuit detected by the current detecting circuit reach the target value.

5. The battery management circuit of claim 1 , further comprising a second charging channel provided with a boost circuit, wherein the boost circuit is configured to receive initial voltage from the power supply device and increase the initial voltage to a target voltage to charge the battery according to the target voltage, when the power supply device charges the battery through the second charging channel, the initial voltage being lower than total voltage of the battery and the target voltage being higher than the total voltage of the battery.

6. The battery management circuit of claim 5 , wherein the communication control circuit is further configured to control switching between the first charging channel and the second charging channel.

7. The battery management circuit of claim 5 , wherein the first charging channel is provided with a switch transistor to control switching between the first charging channel and the second charging channel.

8. The battery management circuit of claim 1 , wherein the Cuk circuit comprises at least one switch transistor, a first inductor and a second inductor, and a capacitor coupled between the first inductor and the second inductor, the first inductor is further coupled with a positive electrode of the first cell and the second inductor is further coupled with a negative electrode of the second cell, and the at least one switch transistor has one end coupled between the capacitor and one inductor and another end coupled with an electrode of the first cell or the second cell.

9. The battery management circuit of claim 8 , wherein the at least one switch transistor comprises a first switch transistor and a second switch transistor, the first switch transistor has one end coupled between the capacitor and the first inductor, another end coupled with a negative electrode of the first cell, and still another end coupled with the communication control circuit; the second switch transistor has one end coupled between the capacitor and the second inductor, another end coupled with a positive electrode of the second cell, and still another end coupled with the communication control circuit; and the communication control circuit is configured to send the drive signal to the first switch transistor and the second switch transistor respectively in a predetermined time sequence to control direction and speed of energy transfer between the first cell and the second cell.

10. A device to be charged, comprising:
a battery, comprising a first cell and a second cell coupled in series; and
a battery management circuit, comprising a first charging channel, a Cuk circuit, and a communication control circuit, wherein
the first charging channel, through which at least one of charging voltage and charging current is received from a power supply device and applied directly to the battery for charging the at least one of the charging voltage and the charging current received from the power supply device is applied directly to the battery without being converted;
the communication control circuit is configured to communicate with the power supply device to make a magnitude of at least one of the charging voltage and the charging current from the power supply device match a present charging stage of the battery, when the power supply device charges the battery through the first charging channel, the present charging stage of the battery is any one of a trickle charging stage, a constant-current charging stage, and a constant-voltage charging stage; and
the communication control circuit is further configured to send a drive signal to the Cuk circuit to drive the Cuk circuit to work, to make energy of the first cell and the second cell be transferred through the Cuk circuit to balance voltage of the first cell and voltage of the second cell, when the voltage of the first cell and the voltage of second cell are unbalanced.

11. The device of claim 10 , wherein the communication control circuit is further configured to acquire at least one of present power and present voltage of the first cell and at least one of present power and present voltage of the second cell before the drive signal is sent to the Cuk circuit to drive the Cuk circuit to work; and
the communication control circuit configured to send the drive signal to the Cuk circuit to drive the Cuk circuit to work is configured to:
send the drive signal to the Cuk circuit to drive the Cuk circuit to work when a difference between at least one of the present power and the present voltage of the first cell, and at least one of the present power and

Assignees

• Guangdong Oppo Mobile Telecommunications Corp Ltd
• Guangdong Oppo Mobile Telecommunication Corp Ltd

Inventors

• Chen Shebiao
• Zhang Jialiang

Classifications

• H02J7/663

  using battery or load disconnect circuits (H02J9/002 takes precedence) · CPC title

• H02J7/94

  in response to battery current · CPC title

• H02J7/42

  with electronic devices having internal batteries, e.g. mobile phones · CPC title

• H02J7/933

  the cycle being controlled or terminated in response to electric parameters · CPC title

• H02J7/865

  Battery or charger load switching, e.g. concurrent charging and load supply (H02J7/50 takes precedence) · CPC title