CHARGING AND DISCHARGING METHOD FOR LITHIUM ION SECONDARY BATTERIES AND CHARGING AND DISCHARGING SYSTEM FOR THE SAME

• US 20130009605A1
• Filed: 02/17/2011
• Published: 01/10/2013
• Est. Priority Date: 03/23/2010
• Status: Abandoned Application

• Current Assignee: NEC Corporation
• Original Assignee: NEC Corporation
• Inventors: Hongo, Hiroo, Kudo, Koji, Sakuma, Hisato, Kuribayashi, Ryosuke
• Application Number:
  US13/265,414
• Publication Number:
  US 20130009605A1
• Time in Patent Office: Days
• US Class Current: 320/134
• CPC Class Codes: H01M 10/0525 Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
• CPC Class Codes: H01M 10/441 for several batteries or cells simultaneously or sequentially
• CPC Class Codes: H01M 4/505 of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy
• CPC Class Codes: H02J 7/0013 acting upon several batteries simultaneously or sequentially H02J7/1423 takes precedence
• CPC Class Codes: H02J 7/00302 Overcharge protection
• CPC Class Codes: H02J 7/00306 Overdischarge protection
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries

Abstract

A first threshold that is lower than a progressively deteriorating SOC that is an SOC in which a battery performance of the lithium ion secondary battery deteriorates when the lithium ion secondary battery is stored and a second threshold that is greater than the progressively deteriorating SOC are preset. A computer controls a switch provided between electric wires and the lithium ion secondary battery, an electric power supply source that supplies electric power necessary to charge the lithium ion secondary battery and a load that consumes electric power discharged from the lithium ion secondary battery are connected to the electric wires, such that a charging operation for the lithium ion secondary battery is continued from the first threshold to the second threshold when the lithium ion secondary battery is charged based on value of the SOC of the lithium ion secondary battery, the value of the SOC is transmitted from a monitor device that detects the value of the SOC of the lithium ion secondary battery and that controls the switch such that a discharging operation for the lithium ion secondary battery is continued from the second threshold to the first threshold when the lithium ion secondary battery is discharged.

Claims

1. A charging and discharging method for lithium ion secondary batteries having a manganese positive electrode material, the method comprising the steps of:

causing a computer to store a preset first threshold that is lower than a progressively deteriorating SOC that is an SOC in which battery performance of said lithium ion secondary battery deteriorates when the lithium ion secondary battery is stored and to store a preset second threshold that is greater than said progressively deteriorating SOC;

causing said computer to control a switch provided between electric wires and said lithium ion secondary battery, an electric power supply source that supplies electric power necessary to charge said lithium ion secondary battery and a load that consumes electric power discharged from said lithium ion secondary battery that is connected to said electric wires, such that a charging operation for said lithium ion secondary battery is continued from said first threshold to said second threshold when said lithium ion secondary battery is charged based on a value of the SOC of said lithium ion secondary battery, the value of the SOC being transmitted from a monitor device that detects the value of the SOC of said lithium ion secondary battery; and

causing said computer to control said switch such that a discharging operation for said lithium ion secondary battery is continued from said second threshold to said first threshold when said lithium ion secondary battery is discharged.

2. The charging and discharging method for lithium ion secondary batteries according to claim 1,

wherein when said plurality of lithium ion secondary batteries are charged, the first control step is performed by causing said computer to control said plurality of switches provided corresponding to said lithium ion secondary batteries such that said lithium ion secondary batteries that have reached said first threshold are successively charged from said first threshold to said second threshold, and

wherein when said plurality of lithium ion secondary batteries are discharged, the second control step is performed by causing said computer to control said switches provided corresponding to said lithium ion secondary batteries such that said lithium ion secondary batteries that have reached said second threshold are successively discharged from said second threshold to said first threshold.

3. The charging and discharging method for lithium ion secondary batteries according to claim 1,

wherein said positive electrode material of said lithium ion secondary batteries is mainly lithium manganese oxide.

4. A charging and discharging system that controls charging and discharging for lithium ion secondary batteries having a manganese positive electrode material, comprising:

a monitor device that detects SOCs of said lithium ion secondary batteries;

switches that connect or disconnect electric wires and said lithium ion secondary batteries, a power supply source that supplies electric power necessary to charge said lithium ion secondary batteries and a load that consumes electric power discharged from said lithium ion secondary batteries that are connected to said electric wires; and

an information processing device that stores a preset first threshold that is lower than a progressively deteriorating SOC that is an SOC in which battery performance of said lithium ion secondary batteries deteriorates when the lithium ion secondary batteries are stored and a preset second threshold that is greater than said progressively deteriorating SOC and that controls said switches such that a charging operation for said lithium ion secondary batteries is continued from said first threshold to said second threshold when said lithium ion secondary batteries are charged and such that a discharging operation for said lithium ion secondary batteries is continued from said second threshold to said first threshold when said lithium ion secondary batteries are discharged based on values of the SOCs of said lithium ion secondary batteries, the values of the SOCs being detected by said monitor device.

5. The charging and discharging system according to claim 4,

wherein said switches are provided corresponding to said lithium ion secondary batteries,

wherein when said plurality of lithium ion secondary batteries are charged, said information processing device controls said switches such that said lithium ion secondary batteries that have reached said first threshold are successively charged from said first threshold to said second threshold, and

wherein when said plurality of lithium ion secondary batteries are discharged, said information processing device controls said switches such that said lithium ion secondary batteries that have reached said second threshold are successively discharged from said second threshold to said first threshold.

6. The charging and discharging system according to claim 4,

wherein said positive electrode material of said lithium ion secondary batteries is mainly lithium manganese oxide.

7. An information processing device that controls charging and discharging for lithium ion secondary batteries having a manganese positive electrode material, comprising:

a storage device that stores a preset first threshold that is lower than a progressively deteriorating SOC that is an SOC in which battery performance of the lithium ion secondary batteries deteriorates when the lithium ion secondary batteries are stored and that stores a preset second threshold that is greater than said progressively deteriorating SOC; and

a processing device that controls switches provided between electric wires and said lithium ion secondary batteries, an electric power supply source that supplies electric power necessary to charge said lithium ion secondary batteries and a load that consumes electric power discharged from said lithium ion secondary batteries that are connected to said electric wires, such that a charging operation for said lithium ion secondary batteries is continued from said first threshold to said second threshold when said lithium ion secondary batteries are charged and such that a discharging operation for said lithium ion secondary batteries is continued from said second threshold to said first threshold when said lithium ion secondary batteries are discharged based on values of the SOCs of said lithium ion secondary batteries, the values of the SOCs being transmitted from a monitor device that detects the values of the SOCs of said lithium ion secondary batteries.

8. The information processing device according to claim 7,

wherein when said plurality of lithium ion secondary batteries are charged, said information processing device controls said switches provided corresponding to said lithium ion secondary batteries such that said lithium ion secondary batteries that have reached said first threshold are successively charged from said first threshold to said second threshold, and

wherein when said plurality of lithium ion secondary batteries are discharged, said information processing device controls said switches provided corresponding to said lithium ion secondary batteries such that said lithium ion secondary batteries that have reached said second threshold are successively discharged from said second threshold to said first threshold.

9. The information processing device according to claim 7,

wherein said positive electrode material of said lithium ion secondary batteries is mainly lithium manganese oxide.