Calculating remaining battery capacity based on battery-side end voltage and device-side end voltage

• US 20080164848A1
• Filed: 03/04/2008
• Published: 07/10/2008
• Est. Priority Date: 06/04/2004
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Tsuchiya, Yukio, Sato, Hideyuki, Sakurai, Masaki
• Granted Patent: US 7,649,339 B2
• Time in Patent Office: Days
• US Class Current: 320/136
• CPC Class Codes: G01R 31/3835 involving only voltage measurements
• CPC Class Codes: H01M 10/48 Accumulators combined with arrangements for measuring, testing or indicating the condition of cells, e.g. the level or density of the electrolyte constructional details of current conducting connections for detecting conditions inside cells or batteries, e.g. details of voltage sensing terminals, H01M50/569
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

A remaining battery capacity indicating apparatus includes an end voltage accumulated value setting unit operable to set an accumulated value indicative of a remaining capacity of a lithium-ion secondary battery, the accumulated value being set in a fully charged state of the battery so that the accumulated value reaches zero when a voltage in the battery is a device-side end voltage. It is determined whether a battery-side end voltage which ends discharges from the lithium-ion secondary battery corresponds to the device-side end voltage. If the battery-side end voltage does not correspond to the device-side end voltage, then the accumulated value is corrected in response to the device-side end voltage. A remaining capacity of the battery, corresponding to the device-side end voltage, is calculated based on the corrected accumulated value, and the calculated remaining capacity of the battery is displayed on a display unit. If the device-side end voltage does not correspond to the battery-side end voltage, then the remaining capacity of the battery is displayed on the device side.

Claims

1. A remaining battery capacity indicating apparatus for detecting a remaining capacity of a charge and discharge battery serving as a power supply for supplying a voltage to an electronic device, comprising:

an end voltage setting unit operable to set a device-side end voltage which ends operations of the electronic device;

an accumulated value setting unit operable to set an accumulated value indicative of a remaining capacity of the battery, the accumulated value being set in a fully charged state of the battery so that the accumulated value reaches zero when a voltage in the battery is the device-side end voltage;

a determining unit operable to determine whether a battery-side end voltage which ends discharges from the battery corresponds to the device-side end voltage;

a correcting unit operable to correct the accumulated value in response to the device-side end voltage if the battery-side end voltage does not correspond to the device-side end voltage;

a calculating unit operable to calculate a remaining capacity of the battery corresponding to the device-side end voltage based on the corrected accumulated value; and

a display unit operable to display the calculated remaining capacity of the battery.

2. A remaining battery capacity indicating apparatus according to claim 1, further comprising:

a communication unit operable to transmit the device-side end voltage from the electronic device to a battery pack including the battery.

3. A remaining battery capacity indicating apparatus according to claim 1, further comprising:

a communication unit operable to transmit the corrected accumulated value from a battery pack including the battery to the electronic device.

4. A method for detecting a remaining capacity of a charge and discharge battery serving as a power supply for supplying a voltage to an electronic device, the method comprising:

setting a device-side end voltage which ends operations of the electronic device;

setting an accumulated value indicative of a remaining capacity of the battery, the accumulated value being set in a fully charged state of the battery so that the accumulated value reaches zero when a voltage in the battery is the device-side end voltage;

determining whether a battery-side end voltage which ends discharges from the battery corresponds to the device-side end voltage;

correcting the accumulated value in response to the device-side end voltage if the battery-side end voltage does not correspond to the device-side end voltage;

calculating a remaining capacity of the battery corresponding to the device-side end voltage based on the corrected accumulated value; and

displaying the calculated remaining capacity of the battery.

5. A method according to claim 4, further comprising:

transmitting the device-side end voltage from the electronic device to a battery pack including the battery.

6. A method according to claim 4, further comprising:

transmitting the corrected accumulated value from a battery pack including the battery to the electronic device.

7. A remaining battery capacity indicating apparatus for detecting a remaining capacity of a charge and discharge battery serving as a power supply for supplying a voltage to an electronic device, comprising:

end voltage setting means for setting a device-side end voltage which ends operations of the electronic device;

accumulated value setting means for setting an accumulated value indicative of a remaining capacity of the battery, the accumulated value being set in a fully charged state of the battery so that the accumulated value reaches zero when a voltage in the battery is the device-side end voltage;

judging means for determining whether a battery-side end voltage which ends discharges from the battery corresponds to the device-side end voltage;

correcting means for correcting the accumulated value in response to the device-side end voltage if the battery-side end voltage does not correspond to the device-side end voltage;

calculating means for calculating a remaining capacity of the battery corresponding to the device-side end voltage based on the corrected accumulated value; and

display means for displaying the calculated remaining capacity of the battery.