Battery pack system

• US 6,955,859 B2
• Filed: 05/22/2002
• Issued: 10/18/2005
• Est. Priority Date: 05/28/2001
• Status: Expired due to Fees

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation), Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Kimura, Tadao, Nakanishi, Toshiaki
• Primary Examiner(s): Barr, Michael
• Assistant Examiner(s): WILLS, MONIQUE M
• Application Number:
  US10/153,467
• Publication Number:
  US 20020177034A1
• Time in Patent Office: 1,245 Days
• Field of Search: 429/3, 429/7, 429/50, 429/90, 429/121, 429/122, 429/125, 429/151, 429/153, 429/161, 429/162, 320/125, 320/151, 320/153, 320/161, 320/162
• US Class Current: 429/7
• CPC Class Codes: H01M 10/30 Nickel accumulators H01M10/34 takes precedence
• CPC Class Codes: H01M 10/42 Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells H01M10/60 takes precedence
• CPC Class Codes: H02J 7/00038 using passive battery identification means, e.g. resistors or capacitors identification by mechanical connections H02J7/0045
• CPC Class Codes: H02J 7/00047 with provisions for charging different types of batteries
• CPC Class Codes: H02J 7/0048 Detection of remaining charge capacity or state of charge [SOC]
• CPC Class Codes: H02J 7/007 Regulation of charging or discharging current or voltage
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

A battery pack system is provided that can be replaced easily without modifying the side of an appliance using this battery pack system, on which charging is controlled by a voltage control, and includes a secondary battery with high performance that undergoes charging by a current control. A battery pack system is provided with a battery including at least one unit cell serving as a secondary battery with a positive electrode containing a nickel oxide as an active material, a detecting portion for detecting a battery state including a charging state in the battery, and a current adjusting portion, that is connected in series with the battery, for adjusting a charging current value according to the charging state detected by the detecting portion.

Claims

1. A battery pack device comprising:

terminals to be connected to a side of an appliance;

a battery comprising at least one unit cell serving as a secondary battery with a positive electrode containing a nickel oxide as an active material;

a detecting portion for detecting a battery state including a charging state in the battery and outputting a control signal according to the detected charging state; and

a current adjusting portion, that is connected in series with the battery, for adjusting a charging current value according to the control signal supplied by the detecting portion;

wherein the detecting portion and the current adjusting portion are part of the device when the terminals are connected to an appliance.

2. The battery pack device according to claim 1, wherein the current adjusting portion comprises a variable resistor for changing a resistance according to the charging state detected by the detecting portion.

3. The battery pack device according to claim 2, wherein the variable resistor comprises:

a plurality of switching elements, and

a plurality of resistance elements, respectively corresponding to the plurality of switching elements,

wherein the plurality of switching elements are opened and closed selectively according to the charging state detected by the detecting portion.

4. The battery pack device according to claim 2, wherein the variable resistor increases the resistance according to the charging state detected by the detecting portion at the time of continuously charging the battery and decreases the resistance at the time of actually using the battery.

5. The battery pack device according to claim 1, further comprising:

a first rectifying element that is connected in series with the current adjusting portion and conducts a current only in a charging direction of the battery; and

a second rectifying element that is connected in parallel with the current adjusting portion and the first rectifying element and conducts a current only in a discharging direction of the battery.

6. The battery pack device according to claim 1, wherein the detecting portion detects the charging state based on a terminal voltage, a charging discharging current and a temperature of the battery.

7. The battery pack device according to claim 1, wherein the secondary battery is a nickel-metal hydride secondary battery.