Battery manager

• US 6,268,711 B1
• Filed: 05/05/2000
• Issued: 07/31/2001
• Est. Priority Date: 05/05/1999
• Status: Expired due to Term

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Bearfield, Jonathan Matthew
• Primary Examiner(s): Wong, Peter S.
• Assistant Examiner(s): LUK, LAWRENCE W
• Application Number:
  US09/565,271
• Time in Patent Office: 452 Days
• Field of Search: 320/117, 320/116, 320/126, 307/64, 307/65, 307/66
• US Class Current: 320/117
• CPC Class Codes: H02J 7/0024 Parallel/serial switching of connection of batteries to charge or load circuit
• CPC Class Codes: H02J 7/0025 Sequential battery discharge in systems with a plurality of batteries
• CPC Class Codes: H02J 7/0063 with circuits adapted for supplying loads from the battery
• CPC Class Codes: H02J 7/36 Arrangements using end-cell switching

Abstract

A battery manager that provides the ability to switch multiple batteries, battery cells, or other forms of power sources to power external devices individually, in series, and/or in parallel. The device is typically electronic based and consists of voltage level detecting circuits for comparing each power source to a reference voltage, FET control logic for controlling the switching matrix, and a switching matrix which accomplishes the required configuration of power sources to provide an output power source. The invention can be extended with the addition of an output power monitor, DC/DC converter, and control signals that augment internal switching. Depending upon implementation requirements, the battery manager can be in the form of a single integrated circuit.

Claims

1. A battery manager comprising:

A. a reference voltage source providing a reference voltage on a reference voltage lead;

B. a plurality of battery voltage level detectors each connected to at least one connector for a storage battery and each connected to the reference voltage lead, each battery voltage level detector providing a detector output signal on a detector output lead, wherein the battery voltage level detectors are each operational amplifier that provide the detector output signal when a battery voltage on the connector for the storage battery falls below the reference voltage;

C. a plurality of switching control circuits having inputs connected to the detector output leads of all the batter level detectors and providing switching output signals on switching output leads, wherein the switching control circuits include logic gates; and

D. a plurality of switching circuits having control inputs connected to the switching output leads, having power inputs connected to individual ones of the connectors for the storage batteries and having output leads providing a supply power output of the battery manager circuit, the switching circuits being arranged selectively to connect the connectors for the storage batteries in series and in parallel.

2. A battery manager comprising:

A. a reference voltage source providing a reference voltage on a reference voltage lead;

B. a plurality of battery voltage level detectors each connected to at least one connector for a storage battery and each connected to the reference voltage lead, each battery voltage level detector providing a detector output signal on a detector output lead;

C. a plurality of switching control circuits having inputs connected to the detector output leads of all the batter level detectors and providing switching output signals on switching output leads; and

D. a plurality of switching circuits having control inputs connected to the switching output leads, having power inputs connected to individual ones of the connectors for the storage batteries and having output leads providing a supply power output of the battery manager circuit, the switching circuits being arranged selectively to connect the connectors for the storage batteries in series and in parallel;

wherein there is one and another connectors for a first storage battery and one and another connectors for a second storage battery and the switching circuits include a first transistor connected between the one connector for the first storage battery and the power output, a second transistor connected between the one connector for the second storage battery and the power output, a third transistor connected between the other connector for the first storage battery and the one connector for the second storage battery and a fourth transistor connected between the other connectors for the first and second storage batteries.

3. A battery manager comprising:

A. a reference voltage source providing a reference voltage on a reference voltage lead;

B. a plurality of battery voltage level detectors each connected to at least one connector for a storage battery and each connected to the reference voltage lead, each battery voltage level detector providing a detector output signal on a detector output lead;

C. a plurality of switching control circuits having inputs connected to the detector output leads of all the batter level detectors and providing switching output signals on switching output leads; and

D. a plurality switching circuits having control inputs connected to the switching output leads, having power inputs connected to individual ones of the connectors for the storage batteries and having output leads providing a supply power output of the battery manager circuit, the switching circuits being arranged selectively to connect the connectors for the storage batteries in series and in parallel, wherein the switching circuits include a parallel control input lead that causes the switching circuits to connect the connectors for the storage batteries in parallel.

4. A, process of selectively connecting plural storage batteries to a power output lead supplying electrical power to an external device comprising;

A. switching a first storage battery into connection with the power output lead to provide electrical power to the external device;

B. sensing the ability of the first storage battery to supply electrical power to the external device;

C. switching at least a second storage battery into a parallel connection with the first storage battery to the power output lead to supply sufficient electrical power to the external device when the first battery is unable to supply sufficient electrical power to the external device;

D. sensing the ability of the first and second storage batteries to supply electrical power to the external device; and

E. switching at least one of the first and second storage batteries out of parallel connection to the power output lead while the other of the first and second storage batteries maintains supplying sufficient electrical power to the external device.

5. The process of claim 4 including switching at least a second storage battery into a parallel connection with the first storage battery at an initial application of electrical power to the external device.

6. A process of selectively connecting plural storage batteries to a power output lead supplying electrical power to an external device comprising;

A. switching a first storage battery into connection with the power output lead to provide electrical power to the external device;

B. sensing the ability of the first storage battery to supply electrical power to the external device;

C. switching a second storage battery into connection with the power output lead and disconnecting the first storage battery from connection with the power output lead to supply sufficient electrical power to the external device when the first battery is unable to supply sufficient electrical power to the external device;

D. sensing the ability of the second storage, battery to supply electrical power to the external device; and

E. switching the first and second storage batteries into series connection to the power output lead to supply sufficient electrical power to the external device when the first and second batteries individually are unable to supply sufficient electrical power to the external device.

7. A process of selectively connecting plural storage batteries to a power output lead supplying electrical power to an external device comprising;

A. sensing the ability of a first storage battery to supply electrical power to the external device;

B. sensing the ability of a second storage battery to supply electrical power to the external device;

C. selectively switching the first and second storage batteries into connection with the power output lead to supply sufficient electrical power to the external device.