In-vehicle power storage device and control method thereof

Patent metadata

Field	Value
Publication number	US-11239671-B2
Application number	US-201214397801-A
Country	US
Kind code	B2
Filing date	Oct 10, 2012
Priority date	Oct 10, 2012
Publication date	Feb 1, 2022
Grant date	Feb 1, 2022

Abstract

An in-vehicle power storage device that discharges a battery in a case where collision of a vehicle is detected or predicted, and stops discharging the battery when an over-discharged state has not been reached, and a control method thereof. The in-vehicle power storage device includes: a battery mounted in a vehicle; charge-state detection means for detecting a charge state of the battery; and a discharging load for discharging the battery, and a control device which includes: battery charge-state detection means for detecting a charge state; a battery discharger means for discharging the battery using the load if collision of the vehicle is detected or predicted; and discharge stopping means to stop discharging the battery before the battery becomes over-discharged.

First claim

The invention claimed is:

1. An in-vehicle power storage device comprising: a battery mounted in a vehicle and comprising a plurality of battery cells; battery charge-state detector which detects a charge state of the battery; and a discharging load for discharging the battery, the in-vehicle power storage device further comprising:
a control device, the control device including:
a battery discharger which performs an emergency discharging of the battery by using the load in a case where collision of the vehicle is detected or predicted and which, while discharging the battery, stops discharging the battery when the charge state of the battery detected by the battery charge-state detector becomes less than or equal to a predetermined value at which overdischarge has not been reached yet,
wherein the control device includes a battery abnormality detector which determines whether an abnormality of the battery has occurred, after the emergency discharging is started by the battery discharger and while the emergency discharging is performed but before the battery is discharged to the predetermined value higher than a near-zero value, and in a case where the battery abnormality detector determines that the battery is abnormal, the discharging is not stopped when an overall charge state of the battery detected by the battery charge-state detector becomes less than or equal to the predetermined value, and the battery is discharged until the overall charge state of the battery comprising the plurality of battery cells represents the near-zero value,
wherein the power storage device further includes a notifier providing external notification of said emergency discharging, and
wherein, when the collision of the vehicle is detected or predicted, the battery discharger starts discharging the battery without waiting for the battery abnormality detector to determine whether the abnormality of the battery has occurred, and stops discharging the battery before the battery enters an overdischarged state when the abnormality of the battery does not occur.

2. The in-vehicle power storage device according to claim 1 , wherein the plurality of battery cells are connected in series with or in parallel with each other, and the load is formed by a bypass circuit including a resistor and circuit opening/closing means.

3. The in-vehicle power storage device according to claim 1 , comprising battery disconnecting means provided between the battery and an electric device to which power is supplied from the battery, wherein
in a case where collision of the vehicle is detected or predicted, after supply of power from the battery to the electric device is stopped by the battery disconnecting means, the battery is discharged by the battery discharger.

4. The in-vehicle power storage device according to claim 1 , wherein said notifier comprises an external notifier which makes, to the outside, notification that said emergency discharging by the battery discharger is being performed or has ended.

5. The in-vehicle power storage device according to claim 1 , comprising a memory for recording that said emergency discharging has been performed by the battery discharger.

6. The in-vehicle power storage device according to claim 1 , wherein the battery is a lithium ion battery, and the overdischarged state represents a state where an electrolyte solution of the lithium ion battery is decomposed, or a state where copper used for a negative electrode is ionized and dissolved in the electrolyte solution in the battery.

7. The in-vehicle power storage device according to claim 1 , wherein the load is mounted in a case for accommodating the battery.

8. The in-vehicle power storage device according to claim 1 , wherein the battery discharger performs the emergency discharging in response to the control device receiving a collision detection signal from an air bag control.

9. The in-vehicle power storage device according to claim 1 , wherein the battery discharger performs the emergency discharging in response to the control device receiving a collision prediction signal from a front detection radar or a camera control device.

10. A method for controlling an in-vehicle power storage device that includes: a battery mounted in a vehicle and comprising a plurality of battery cells; battery charge-state detector for detecting a charge state of the battery; and a discharging load for discharging the battery, the method comprising:
a first operation of emergency discharging the battery by using the load in a case where collision of the vehicle is detected or predicted;
a second operation of determining whether an abnormality of the battery has occurred, while the emergency discharging is performed but before the battery is discharged to a predetermined value higher than a near-zero value;
a third operation of stopping the emergency discharging of the battery which is being performed in the first operation when the overall charge state of the battery comprising the plurality of battery cells becomes less than or equal to the predetermined value;
a fourth operation of, in a case where the abnormality of the battery is detected during said second operation of emergency discharging, discharging the battery until the overall charge state of the battery comprising the plurality of battery cells represents the near-zero value, without stopping discharging the battery when the overall charge state of the battery becomes less than or equal to the predetermined value; and
a fifth operation of providing external notification of said emergency discharging,
wherein, when the collision of the vehicle is detected or predicted, the first operation of emergency discharging the battery is started before the second operation of determining whether the abnormality of the battery has occurred, is completed, and performing the third operation of stopping the emergency discharging of the battery before the battery enters an overdischarged state, when the abnormality of the battery does not occur.

11. The method according to claim 10 , wherein said external notification indicates that said emergency discharge is underway.

12. The method according to claim 10 , wherein said external notification indicates that said emergency discharge has been completed.

13. The method according to claim 10 , further comprising the step of recording in a memory that said emergency discharging has been performed.

14. An in-vehicle power storage device comprising: a battery mounted in a vehicle and comprising a plurality of battery cells; battery charge-state detector which detects a charge state of the battery; and a discharging load for discharging the battery, the in-vehicle power storage device further comprising a control device, the control device including:
a battery discharger which, upon detection of a first problem, begins an emergency discharge operation by which said load is used to discharge said battery until the overall charge state of the battery comprising the plurality of battery cells becomes a first charge state, said battery discharger continuing discharge of said battery past said first charge state in response to a second problem detected after commencement of said discharge operation, said discharge operation terminating at said first charge state when said second problem is not detected during said discharge operation; and
a notifier providing external notification of said emergency discharge,
wherein the battery discharger determines whether an abnormality of the battery has occurred, while the emergency discharge operation is performed but before the battery is discharged to a predetermined value higher t

Assignees

• Yamaguchi Shingo
• Date Toshiaki
• Wachi Satoshi
• Mitsubishi Electric Corp

Inventors

• Yamaguchi Shingo
• Date Toshiaki
• Wachi Satoshi

Classifications

• H02J7/977

  of the battery · CPC title

• H02J7/63

  against overdischarge · CPC title

• H02J7/82 Primary

  Control of state of charge [SOC] · CPC title

• Y02E60/10

  Energy storage using batteries · CPC title

• Y02T10/70

  Energy storage systems for electromobility, e.g. batteries · CPC title