Method of and system for controlling charging of secondary battery

• US 20030169017A1
• Filed: 12/27/2002
• Published: 09/11/2003
• Est. Priority Date: 01/10/2002
• Status: Active Grant

• Current Assignee: Honda Giken Kogyo Kabushiki Kaisha (Honda Motor Company)
• Original Assignee: Honda Giken Kogyo Kabushiki Kaisha (Honda Motor Company)
• Inventors: Sone, Takashi, Ariga, Kyoichi
• Granted Patent: US 6,771,046 B2
• Time in Patent Office: Days
• US Class Current: 320/125
• CPC Class Codes: H02J 7/0069 Charging or discharging for charge maintenance, battery initiation or rejuvenation
• CPC Class Codes: H02J 7/0071 with a programmable schedule
• CPC Class Codes: H02J 7/007182 in response to battery voltage

Abstract

A method of controlling the charging of a secondary battery (battery) without deterioration of a charging/discharging characteristic of the battery. An ordinary charging portion performs a first charging control specified to stop the charging at a charge level less than a full-charge level is used in combination with a refresh charging portion for performing a second charging control specified to stop the charging at a charge level more than the full-charge level. When the charging by the ordinary charging portion is continuously repeated by, for example, 10 times, a switching portion is switched such that the next charging is performed by the refresh charging portion. A counter, which is reset when the charging by the refresh charging portion is terminated, is provided for deciding whether or not the number of times of the repeated charging reaches 10. The counter can be replaced with means having a function of outputting, if a random number generated by a random number generator is a specific value, a switching command to the switching portion.

Claims

1. A method of controlling the charging of a secondary battery, comprising the steps of:

controlling the charging of said secondary battery by using both a first charging control specified to stop the charging at a charge level less than a full-charge level and a second charging control specified to stop the charging at a charge level equal to or more than the full-charge level; and

performing the next charging by said second charging control after the charging by said first charging control is continuously repeated by a specific number of times.

2. A system for controlling the charging of a secondary battery, comprising:

first charging control means for stopping the charging at a charge level less than a full-charge level;

second charging control means for stopping the charging at a charge level equal to or more than the full-charge level;

deciding means for deciding that the charging by said first charging control means is continuously repeated by a specific number of times; and

control switching means for switching based on input from the deciding means that the charging by said first charging control means is continuously repeated by the specific number of times thereby switching said first charging control means to said second charging control means so as to perform the next charging by said second charging control means.

3. The system for controlling the charging of a secondary battery according to claim 2, wherein in said deciding means, the specific number of times of the repeated charging by said first charging control means is set to a value less than 20.

6. The system for controlling the charging of a secondary battery according to claim 2, wherein the battery capacity, less than the full-charge level, at which the charging by said first charging control means is to be stopped, is composed of two-step battery capacities;

and

selecting means is provided for selecting either of the two-step battery capacities.

7. The system for controlling the charging of a secondary battery according to claim 3, wherein the battery capacity, less than the full-charge level, at which the charging by said first charging control means is to be stopped, is composed of two-step battery capacities;

and

selecting means is provided for selecting either of the two-step battery capacities.

10. The system for controlling the charging of a secondary battery according to claim 6, wherein if a lower one of the two-step battery capacities is selected by said selecting means and said deciding means determines that the charging to a charge level less than the full-charge level is repeated by the specific number of times, said first charging control means is switched to said second charging control means.

11. The system for controlling the charging of a secondary battery according to claim 10, further comprising:

display means for displaying, when said second charging control means is selected, a signal indicating that said selection is canceled.

4. A system for controlling the charging of a secondary battery, comprising:

first charging control means for stopping the charging at a charge level less than a full-charge level;

second charging control means for stopping the charging at a charge level equal to or more than the full-charge level;

a random number generating means for generating a random number each time one charging by said first charging control means is performed; and

control switching means for switching, if the random number generated by said random number generating means corresponds to a specific value equal to or less than the maximum value among the generated random numbers, thereby switching said first charging control means to said second charging control means so as to perform the next charging by said second charging control means.

5. The system for controlling the charging of a secondary battery according to claim 4, wherein the random number generated by said random number generating means is less than 20.

8. The system for controlling the charging of a secondary battery according to claim 4, wherein the battery capacity, less than the full-charge level, at which the charging by said first charging control means is to be stopped, is composed of two-step battery capacities;

and

selecting means is provided for selecting either of the two-step battery capacities.

9. The system for controlling the charging of a secondary battery according to claim 5, wherein the battery capacity, less than the full-charge level, at which the charging by said first charging control means is to be stopped, is composed of two-step battery capacities;

and

selecting means is provided for selecting either of the two-step battery capacities.

12. A method of controlling the charging of a secondary battery, comprising the steps of:

controlling the charging of said secondary battery by using both a first charging control specified to stop the charging at a charge level less than a full-charge level and a second charging control specified to stop the charging at a charge level equal to or more than the full-charge level;

performing the next charging by said second charging control after the charging by said first charging control is continuously repeated by a specific number of times; and

discharging said secondary battery before the charging of said secondary battery if the state of said secondary battery satisfies a specific refresh discharge reference in said second charging control.

13. The method of controlling the charging of a secondary battery according to claim 12, wherein the refresh discharge reference is determined to be satisfied when the remaining capacity of said secondary battery is less than a specific value.

14. The method of controlling the charging of a secondary battery according to claim 12, wherein the refresh discharge reference is determined to be satisfied each time the charging by said second charging control is repeated by a specific number of times.

15. A system for controlling the charging of a secondary battery, comprising:

first charging control means for stopping the charging at a charge level less than a full-charge level;

second charging control means for stopping the charging at a charge level equal to or more than the full-charge level;

deciding means for deciding that the charging by said first charging control means is continuously repeated by a specific number of times;

control means switching means for switching, if it is decided by said deciding means that the charging by said first charging control means is continuously repeated by the specific number of times, thereby switching said first charging control means to said second charging control means so as to perform the next charging by said second charging control means; and

refresh discharging means for discharging, if the state of said secondary battery satisfies a specific refresh discharge reference in the control by said second charging control means, said secondary battery before the charging of said secondary battery.

16. The system for controlling the charging of a secondary battery according to claim 15, wherein said refresh discharging means is configured to discharge said secondary battery when the remaining capacity of said secondary battery is less than a specific value.

17. The system for controlling the charging of a secondary battery according to claim 15, wherein said refresh discharging means is configured to discharge said secondary battery each time the charging by said second charging control means is repeated by a specific number of times.

18. A method of controlling the charging of a secondary battery, comprising the steps of:

controlling the charging of said secondary battery by using both a first charging control specified to stop the charging at a charge level less than a full-charge level and a second charging control specified to stop the charging at a charge level equal to or more than the full-charge level;

performing the next charging by said second charging control after the charging by said first charging control is continuously repeated by a specific number of times;

performing the charging by said first charging control at a first charging current; and

performing the charging by said second charging control by a preceding charging performed at a second charging current larger than the first charging current and a subsequent charging performed at a third charging current smaller than the first charging current.

19. A system for controlling the charging of a secondary battery, comprising:

cut-off voltage storing means for setting a cut-off voltage corresponding to a specific capacity less than a full-charge level of said second battery;

first charging control means for charging said secondary battery at a first charging current and stopping the charging when a charging voltage of said secondary battery reaches said cut-off voltage;

second charging control means for charging said secondary battery at a second charging current larger than the first charging current until the charging voltage of said secondary battery reaches the cut-off voltage, and then charging said secondary battery at a third charging current smaller than the first charging current until the charge level of said secondary battery reaches the full-charge level; and

switching means for selecting either said first charging control means or said second charging control means.

20. The system for controlling charging a secondary battery according to claim 19, and further comprising:

full-charge voltage storing means for storing a full-charge voltage of said secondary battery when the charging by said second charging control means is terminated; and

correcting means for correcting a deteriorated proportion of said cut-off voltage on the basis of the value of the full-charge voltage stored in said full-charge voltage storing means.

21. The system for controlling the charging of a secondary battery according to claim 20, and further comprising:

full-charge voltage storing means for storing a full-charge voltage of said secondary battery when the charging by said second charging control means is terminated;

setting means for setting a reference full-charge voltage at a specific temperature of said secondary battery;

temperature storing means for storing a temperature of said secondary battery at the time when the full-charge voltage is stored in said full-charge voltage storing means; and

correcting means for correcting a deteriorated proportion of said cut-off voltage on the basis of the value of the full-charge voltage stored in said full-charge voltage storing means, the value of the temperature of said secondary battery stored in said temperature storing means, and the reference full-charge voltage.