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

• US 7,649,339 B2
• Filed: 03/04/2008
• Issued: 01/19/2010
• Est. Priority Date: 06/04/2004
• Status: Expired due to Fees

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Sakurai, Masaki, Tsuchiya, Yukio, Sato, Hideyuki
• Primary Examiner(s): TSO, EDWARD H
• Application Number:
  US12/074,477
• Publication Number:
  US 20080164848A1
• Time in Patent Office: 686 Days
• Field of Search: 320/107, 320/132, 320/149, 324/426, 324/430, 324/433
• US Class Current: 320/132
• 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 system for detecting a remaining battery capacity, comprising:

an electronic device and a battery connected together including;

a power supplying means for supplying power to the electronic device;

a storage means for at least one of storing a battery-side end voltage which is set based on a discharge characteristic of the power supplying means and storing a device-side end voltage which ends operations of the electronic device;

a sending means for at least one of sending an accumulated value indicating a remaining capacity of the power supplying means to the electronic device and sending the device-side end voltage stored on the storage means;

a receiving means for at least one of receiving the device-side end voltage and receiving the accumulated value for indicating a remaining capacity of the battery from the battery;

a control means for at least one of controlling correcting of the accumulated value based on the device-side end voltage received from the receiving means and the battery-side end voltage stored on the storage means, and send the corrected accumulated value to the electronic device and controlling displaying of the remaining capacity of the battery based on the accumulated value received from the battery;

wherein the battery provides power to the electronic device and is capable of sending the accumulated value to the electronic device and the accumulated value is corrected based on the device-side end voltage which ends operations of the electronic device and the battery-side end voltage is set based on a discharge characteristic of the battery; and

wherein the electronic device sends a device-side end voltage which ends operations of the electronic device to the battery device and calculates the remaining capacity of the battery device based on the accumulated value received from the electronic device.

2. The system according to claim 1, wherein the control means corrects the accumulated value in case the device-side end voltage is higher than the battery-side end voltage.

3. An electronic device to which a battery is connected, the battery provides power to the electronic device and sending an accumulated value to the electronic device, the accumulated value is corrected based on a device-side end voltage which ends operations of the electronic device and a battery-side end voltage which is set based on a discharge characteristic of the battery, comprising:

a power supplying means for power being supplied by the battery connected to the electronic device;

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

a sending means for sending the device-side end voltage stored on the storage means;

a receiving means for receiving the accumulated value for indicating a remaining capacity of the battery from the battery; and

a display control means for controlling displaying of the remaining capacity of the battery based on the accumulated value received from the battery.

4. A battery device which is connected to an electronic device, the electronic device sends a device-side end voltage which ends operations of the electronic device to the battery device and calculates a remaining capacity of the battery device based on an accumulated value received from the electronic device, comprising;

a battery cell;

a power supplying means for supplying power to the electronic device;

a sending means for sending an accumulated value indicating a remaining capacity of the battery cell to the electronic device;

a receiving means for receiving the device-side end voltage;

a storage means for storing a battery-side end voltage which is set based on a discharge characteristic of the battery cell; and

a control means for controlling correcting of the accumulated value based on the device-side end voltage received from the receiving means and the battery-side end voltage stored on the storage means, and send the corrected accumulated value to the electronic device.

5. The battery device according to claim 4, wherein the control means corrects the accumulated value in case the device-side end voltage is higher than the battery-side end voltage.