Charging control method for a rechargeable battery and portable computer

• US 9,634,511 B2
• Filed: 10/27/2015
• Issued: 04/25/2017
• Est. Priority Date: 04/02/2010
• Status: Active Grant

• Current Assignee: Lenovo (Beijing) Limited (Lenovo Group Ltd.)
• Original Assignee: Lenovo (Beijing) Limited (Lenovo Group Ltd.)
• Inventors: Zhao, Shuangcheng, Cheng, Xiaoren, Yao, Ling, Lin, Weizhi
• Primary Examiner(s): TRAN, VINCENT HUY
• Application Number:
  US14/924,322
• Publication Number:
  US 20160049806A1
• Time in Patent Office: 546 Days
• Field of Search: 713300
• CPC Class Codes: G06F 1/26 Power supply means, e.g. regulation thereof for memories G11C
• CPC Class Codes: H02J 7/00 Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• CPC Class Codes: H02J 7/0071 with a programmable schedule

Abstract

Disclosed are charging control methods for a rechargeable battery and portable computers. The charging control method includes acquiring a control parameter for a charge current of the rechargeable battery; modifying, based on the control parameter, the charge current from a first charge current to a second charge current less than the first charge current; and charging the rechargeable battery with the second charge current. Compared with conventional methods of charging the battery always with the maximal charge current, the present disclosure can improve the battery'"'"'s lifetime.

Claims

1. A charging control method, comprising:

acquiring a decision parameter for a charge mode;

deciding, based on the decision parameter, whether a first charge mode or a second charge mode is adopted in a current charging operation;

charging a rechargeable battery with a first charge voltage in the first charge mode, and charging the rechargeable battery with a second charge voltage larger than the first charge voltage in the second charge mode;

acquiring a control parameter for a charge current of the battery while the battery is charged in the first or second charge mode, wherein the control parameter for the charge current comprises;

a first charge duration counted since starting charge, a second charge duration counted since a voltage of the battery reaches a first preset voltage threshold, and a temperature of the battery;

modifying, based on the control parameter, the charge current from a first charge current to a second charge current less than the first charge current; and

charging the battery with the second charge current;

wherein, time counted from when the voltage of the battery reaches the first preset voltage threshold until the battery is fully charged is divided into at least two non-overlapping time periods each corresponding to a respective charge current, wherein a first one of any adjacent time periods of the at least two time periods corresponds to a charge current larger than that corresponding to a second one of the any adjacent time periods; and

wherein a duration in which the battery is charged with a charge current exceeding a preset current intensity is reduced as the temperature of the battery increases.

2. The charging control method of claim 1, wherein:

when the second charge duration shifts from the first time period to the second time period, the charge current of the battery is modified, based on the control parameter, from a first charge current corresponding to the first time period to a second charge current corresponding to the second time period.

3. The charging control method of claim 2, wherein the charge current of the battery is a maximal charge current until the voltage of the battery reaches the first preset voltage threshold.

4. A portable computer comprising a mainboard, a rechargeable battery connected to the mainboard, and a charging circuit configured to charge the battery,

wherein the portable computer further comprises a first charging control device configured to control charging of the battery provided in the portable computer and comprising:

a second acquisition module configured to acquire a decision parameter for a charge mode;

a mode decision module configured to decide, based on the decision parameter, whether a first charge mode or a second charge mode is adopted in a current charging operation; and

a voltage control module configured to control the charging circuit to charge the battery with a first charge voltage in the first charge mode, and to charge the battery with a second charge voltage larger than the first charge voltage in the second charge mode; and

wherein the portable computer further comprises a second charging control device configured to control charging of the battery in the first or second charge mode and comprising;

a first acquisition module configured to acquire a control parameter for a charge current of the battery while the battery is charged in the first or second charge mode; and

a current control module configured to control the charging circuit based on the control parameter, so that the charge current generated by the charging circuit is modified from a first charge current to a second charge current less than the first charge current, and the battery is charged with the second charge current;

wherein the control parameter for the charge current comprises;

a first charge duration counted since starting charge, a second charge duration counted since a voltage of the battery reaches a first preset voltage threshold, and a temperature of the battery;

wherein time counted from when the voltage of the battery reaches the first preset voltage threshold until the battery is fully charged is divided into at least two non-overlapping time periods each corresponding to a respective charge current, wherein a first time period of any adjacent time periods of the at least two time periods corresponds to a charge current larger than that corresponding to a second time period of the any adjacent time periods;

wherein a duration in which the battery is charged with a charge current exceeding a preset current intensity is reduced as the temperature of the battery increases.

5. The portable computer of claim 4, wherein:

when the second charge duration shifts from the first time period to the second time period, the current control module is configured to control the charging circuit so that the charge current of the battery generated by the charging circuit is modified from a first charge current corresponding to the first time period to a second charge current corresponding to the second time period.

6. The portable computer of claim 5, wherein the charge current of the battery is a maximal charge current until the voltage of the battery reaches the first preset voltage threshold.