JP5845908B2 - Power supply - Google Patents

Description

  The present invention relates to a power supply device mounted on an electric vehicle or a hybrid vehicle.

2. Description of the Related Art A power supply device that supplies electric power to a motor is used in an electric vehicle or a hybrid vehicle that uses a motor as a drive source.
The power supply device is configured by connecting a plurality of battery modules (battery blocks) in which a plurality of battery cells are connected in series since a high-voltage DC power is supplied to the motor.
Depending on the state of use of the battery cell, gas is generated from the electrode body, so that the internal pressure in the battery cell rises and the side surface of the battery cell expands. Battery cells whose deformation exceeds the allowable range have deteriorated performance and need to be replaced.
Therefore, a technique has been proposed in which detection means such as a switch or pressure sensor for detecting deformation of the battery cell is provided (see Patent Documents 1 and 2).

Special table 2011-505650 gazette JP 2006-24445 A

However, in the above prior art, when each battery cell is shaken by acceleration / deceleration or vibration during traveling of the vehicle, the force due to the shake acts on the switch or the pressure sensor, so that the battery cell is not deformed. There is a concern that it may be erroneously detected that there is deformation.
The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a power supply device that is advantageous in accurately notifying deformation of a battery cell.

  In order to achieve the above object, the present invention is a power supply device that is mounted on a vehicle and includes a plurality of battery cells, and the battery cells that are adjacent to the battery cells that are arranged so that the side surfaces face each other at intervals. It is determined that the two side surfaces of the battery cell are in contact with each other by the contact determination unit that determines that the side surfaces of the battery cells are in contact, the shake determination unit that determines that the vehicle is not shaken, and the contact determination unit. And a notifying means for notifying that deformation has occurred in the battery cell, and the notifying means operates when it is determined by the shake determining means that no shaking has occurred.

According to the first aspect of the present invention, when it is determined that no shaking has occurred by the shaking determination means, the battery is determined when the contact determination means determines that the two side surfaces of the battery cell are in contact with each other. The control means notifies that the cell has been deformed.
Therefore, since the determination by the contact determination unit is performed in a state where the possibility that the battery cell is displaced due to the acceleration / deceleration or the vibration caused by the traveling of the vehicle is low, it is advantageous in accurately reporting the deformation of the battery cell. Become.
According to the second aspect of the present invention, when the side surface of the battery cell swells, the pressure sensor is attached to the center of the side surface that is displaced the most, which is advantageous in accurately determining the deformation of the battery cell.
According to the third and fourth aspects of the invention, since the determination by the contact determination unit is performed in a state where the vehicle is completely stopped, it is advantageous in accurately determining the deformation of the battery cell.
According to the invention described in claim 5, since the determination by the contact determination means is performed both in the state where the vehicle is completely stopped and in the state where the vehicle is traveling at a constant speed, the deformation of the battery cell is determined. This is advantageous in determining the deformation of the battery cell earlier.
According to the sixth aspect of the invention, since the battery cell in which the deformation has occurred can be easily specified by the specifying means, it is advantageous in improving the efficiency of the battery cell replacement work.

2 is a block diagram showing a configuration of a power supply device 10. FIG. 2 is a perspective view of a battery cell 12. FIG. 2 is a front view of a battery cell 12. FIG. It is a perspective view which shows an example of the battery module which connected the some battery cell 12 in series. (A) is explanatory drawing which shows the state which both the two side surfaces 3404 which the adjacent two battery cell 12 opposes swelled, (B) is one of the two side surfaces 3404 which the two adjacent battery cells 12 oppose. It is explanatory drawing which shows the swelled state. It is explanatory drawing which shows an example of the data table with which pressure sensor identification information and battery cell identification information were matched. 4 is a flowchart showing the operation of the power supply device 10.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
As shown in FIG. 1, the power supply device 10 is mounted on an electric vehicle such as an electric vehicle or a hybrid vehicle that uses a motor as a drive source, and supplies power to a traveling motor.
The power supply device 10 includes a plurality of battery cells 12, a pressure sensor 14, a vehicle speed sensor 16, a shift position sensor 18, an acceleration sensor 20, a notification lamp 22, a notification buzzer 24, an ECU 26, and an interface 28. It is configured to include.

First, the configuration of the battery cell 12 will be described.
The battery cell 12 is a secondary battery, and in the present embodiment, the case where the battery cell 12 is configured by a lithium ion secondary battery will be described. However, the present invention is applied to a secondary battery other than a lithium ion secondary battery. Is also applicable.
As shown in FIGS. 2 and 3, the battery cell 12 of the present embodiment includes an electrode body 30 and a case 32 that houses the electrode body 30.
The case 32 has a horizontally long rectangular plate shape and includes a main body portion 34 and a lid portion 36. As the material of the main body 34 and the lid 36, various conventionally known metal materials such as stainless steel, aluminum, and steel can be used.
The main body portion 34 includes a bottom surface 3402, a pair of side surfaces 3404 parallel to each other, and a pair of end surfaces 3406 parallel to each other, and has an accommodation space whose upper part is open.
The electrode body 30 is housed in the housing space of the main body 34.
The electrode body 30 is composed of a wound body 30A in which a strip with a separator interposed between a positive electrode and a negative electrode is wound a plurality of times.
More specifically, the electrode body 30 includes a positive electrode, a negative electrode, and two separators.
The positive electrode has a strip shape having a length larger than the width.
The positive electrode has a three-layer structure, and is composed of a positive electrode current collector foil located at the center in the thickness direction and a positive electrode active material formed on both surfaces thereof. The positive electrode current collector foil is connected to a positive electrode 38 described later via a positive current collector 3010.
Aluminum foil is used as the positive electrode current collector foil, and lithium cobaltate or the like is used as the positive electrode active material.

The negative electrode has a strip shape having a length larger than the width.
The negative electrode has a three-layer structure, and is composed of a negative electrode current collector foil located at the center in the thickness direction and negative electrode active materials formed on both surfaces thereof. The negative electrode current collector foil is connected to a negative electrode 40 described later via a negative current collector 3012.
A copper foil is used as the negative electrode current collector foil, and a carbon material or the like is used as the negative electrode active material.
In FIG. 3, reference numeral 3002 indicates an electrode plate constituting a positive electrode or a negative electrode, and reference numeral 3004 indicates an active material application portion to which a positive electrode active material or a negative electrode active material is applied.

The two separators have a strip shape having a length larger than the width, and are composed of a porous insulating film capable of moving lithium ions.
The electrode body 30 has an oval shape in which a positive electrode and a negative electrode are overlapped with each other with two separators interposed therebetween and wound a plurality of times, and the cross section is flat.
Specifically, the separator, the positive electrode, the separator, and the negative electrode are overlapped in this order, and are wound a plurality of times with the separator facing outside and the negative electrode facing inside.

The lid portion 36 is joined to the main body portion 34 so as to close the accommodation space.
The lid 36 is provided with a positive electrode 38 and a negative electrode 40 that are connected to the electrode body 30, and the positive electrode 38 is connected to the positive electrode of the electrode body 30 through a positive current collector. The negative electrode 40 is connected to the negative electrode of the electrode body 30 through a negative current collector.
The battery cell 12 having the case 32 having a horizontally long rectangular plate shape is completed by joining the lid portion 36 to the main body portion 34 in which the electrode body 30 is accommodated.

As shown in FIG. 4, the plurality of battery cells 12 are accommodated and held in the tray 35 in such a state that the side surfaces 3404 of the case 32 are arranged in parallel and facing each other with a space therebetween, and the tray 35 is a frame (not shown). It is attached to the car body via
A plurality of battery cells 12 accommodated in the tray 35 are connected in series to constitute one battery module. In the actual power supply device 10, a plurality of battery modules are connected in series.
Each battery cell 12 is fixed to the tray 35, but when a force due to acceleration / deceleration or vibration associated with traveling of the vehicle acts on the battery cell 12 via the frame and the tray 35, the side surfaces of the adjacent battery cells 12 that face each other. There is a possibility that the frames 3404 may be temporarily displaced in a direction in which they are separated from each other. Such displacement of the battery cell 12 occurs due to a gap between the case 32 of the battery cell 12 and the tray 35, elastic deformation of the tray 35, or the like.

As shown in FIGS. 3 and 4, the pressure sensor 14 has a film shape and is attached to the center of one of the two side surfaces 3404 facing each other in the case 32 of the adjacent battery cell 12. Yes.
The pressure sensor 14 detects the magnitude of the applied pressure and supplies the detection result to the ECU 26.
As the pressure sensor 14, various conventionally known pressure sensors 14 such as a sensor that converts a resistance value that changes according to the magnitude of pressure into an electrical signal can be used.
As shown by a two-dot chain line in FIG. 5A, the pressure sensor 14 is pressed from the two side surfaces 3404 when the cases 32 of the two adjacent battery cells 12 swell and the side surfaces 3404 come into contact with each other. Detect pressure with.
5B, when one case 32 of the two adjacent battery cells 12 does not swell, but the other case 32 swells and the side surfaces 3404 come into contact with each other. The pressure sensor 14 detects pressure by being pressed from the two side surfaces 3404.
The pressure sensor 14 may be attached to a location other than the center of the side surface 3404 of the battery cell 12.
However, when the side surface 3404 of the battery cell 12 swells, the center of the side surface 3404 is most significantly displaced. Therefore, when the pressure sensor 14 is attached to the center of the side surface 3404 of the battery cell 12 as in the present embodiment, the battery This is advantageous in accurately determining the deformation of the cell 12.

As shown in FIG. 1, the vehicle speed sensor 16 detects the traveling speed of the vehicle and supplies the detection result to the ECU 26.
The shift position sensor 18 detects the position of the shift range and supplies the detection result to the ECU 26.
The acceleration sensor 20 detects acceleration applied to the vehicle and supplies the detection result to the ECU 26. Such an acceleration sensor 20 may be an existing acceleration sensor mounted on the vehicle in order to detect vibration or acceleration of the vehicle, or may be newly provided.
For example, the notification lamp 22 is incorporated in an instrument panel, and is lit (flashes) in response to an instruction from the ECU 26 to notify the driver that the battery cell 12 has been deformed.
The notification buzzer 24 is audible in response to an instruction from the ECU 26 to notify the driver that the battery cell 12 has been deformed.
Therefore, the notification lamp 22 and the notification buzzer 24 function as notification means for notifying that deformation has occurred in the battery cell 12.

The ECU 26 receives detection results from the pressure sensor 14, the vehicle speed sensor 16, the shift position sensor 18, and the acceleration sensor 20, and controls the operation of the notification lamp 22 and the notification buzzer 24.
The ECU 26 includes a CPU, a ROM, a RAM, an interface 28, and the like connected via a bus line. The ROM stores a control program executed by the CPU, and the RAM provides a working area. Then, the CPU executes the control program to realize the contact determination unit 26A, the shake determination unit 28B, and the control unit 26C.

The contact determination unit 26 </ b> A determines that two opposing side surfaces 3404 of adjacent battery cells 12 are in contact with each other.
In the present embodiment, the contact determination unit 26 </ b> A determines that the two opposing side surfaces 3404 of the battery cell 12 are in contact with each other based on the detection result from the pressure sensor 14.
Specifically, when the pressure detected by the pressure sensor 14 is equal to or higher than a predetermined reference value, it is determined that the two opposite side surfaces 3404 of the battery cell 12 are in contact with each other.

The shake determination unit 26B determines that the vehicle is not shaken.
The following three types of operations are exemplified as determination operations by the shake determination unit 26B.
1) The shake determination unit 26B determines that the vehicle is not shaken when the shift range detected by the shift position sensor 18 is the parking position.
In this case, it is determined that no shaking has occurred when the vehicle is completely stopped.
2) The shake determination unit 26B determines that the vehicle is not shaken when the vehicle speed detected by the vehicle speed sensor 16 is zero.
In this case, as in 1), it is determined that no shaking has occurred when the vehicle is completely stopped.
3) The shake determination unit 26B determines that the vehicle is not shaken when the acceleration detected by the acceleration sensor 20 is equal to or less than a predetermined threshold.
In this case, it is determined that the vehicle is not shaken in any case where the vehicle is completely stopped or the vehicle is traveling at a constant speed.

The control means 26C is a battery cell when the contact determination means 26A determines that the two side surfaces 3404 of the battery cell 12 are in contact with each other while the vibration determination means 26B determines that no vibration has occurred. 12 is notified by the notification lamp 22 and the notification buzzer 24.
For example, consider a case where the side surface 3404 of the battery cell 12 has a small bulge, the degree of deterioration of the battery cell 12 is slight, and it is not necessary to notify the deformation of the battery cell 12.
In this case, in a state where the vehicle is not shaken, the pressure force is not applied to the pressure sensor 14 by the side surface 3404. However, when the vehicle shakes, the battery cell 12 is temporarily displaced and the pressure sensor 14 is moved to the side surface. 3404 comes into contact. Then, the contact determination unit 26A determines that the two side surfaces 3404 of the battery cell 12 are in contact with each other, and the control unit 26C erroneously detects that the deformation of the battery cell 12 has occurred, resulting in inconvenience of erroneous notification. .
Therefore, when it is determined that the two side surfaces 3404 of the battery cell 12 are in contact with each other in a state where it is determined that no shaking has occurred as in the present embodiment, the battery cell 12 is deformed. If this is detected, it is possible to avoid the erroneous detection and erroneous notification as described above.

The control unit 26C includes an identification unit 26D and a specifying unit 26E.
The identification means 26D holds identification information for identifying individual battery cells 12, and the specifying means 26E contacts the two side surfaces 3404 by the contact determination means 26A when the notification means notifies the deformation of the battery cells 12. Are determined using the battery cell identification information of the two battery cells 12.
More specifically, individual battery cell identification information is assigned to each battery cell 12, and the battery cell 12 can be specified based on the battery cell identification information.
Specifically, battery cell identification information is written on each battery cell 12. Alternatively, it is set so that the arrangement position of the battery cell 12 can be specified based on the battery cell identification information.
Further, individual pressure sensor identification information is assigned to each pressure sensor 14.

The identification means 26D has a data table as shown in FIG.
That is, the pressure sensor identification information of the first to nth n pressure sensors 14 is P1 to Pn. The battery cell identification information of the first to m-th m battery cells 12 is C1 to Cm. Note that n and m are integers of 1 or more, and m = 2n.
For example, the first pressure sensor 14 (P1) is provided on one side surface 3404 of the two side surfaces 3404 facing each other of the first and second battery cells 12 (C1, C2).
The second pressure sensor 14 (P2) is provided on one side surface 3404 of the two side surfaces 3404 facing each other of the second and third battery cells 12 (C2, C3).
The third pressure sensor 14 (P3) is provided on one side surface 3404 of the two side surfaces 3404 facing each other of the third and fourth battery cells 12 (C3, C4).
Hereinafter, the same applies to the n-th pressure sensor 14 (Pn), the (m−1) -th, and the m-th battery cell 12.
That is, two pieces of battery cell identification information are stored in association with each other for one pressure sensor identification information.
The identification unit 26D is configured to identify the pressure sensor identification information P1 to Pn from the detection result received from each pressure sensor 14.
The specifying unit 26E is based on the data table of FIG. 6 from the pressure sensor identification information of the pressure sensor 14 that has received the detection result when the control unit 26C notifies the deformation of the battery cell 12 by the notification lamp 22 and the notification buzzer 24. To identify two battery cell identification information.
The specifying unit 26E stores the specified battery cell identification information in a storage unit such as a ROM or a RAM.

  The interface 28 exchanges information between the ECU 26 and an external device installed in a repair shop or the like. In the present embodiment, the interface 28 is a battery stored in the storage means. Cell identification information is provided to an external device. Thereby, battery cell identification information can be obtained by the display of an external device.

Next, the operation of the power supply apparatus 10 will be described with reference to the flowchart of FIG.
The processing of FIG. 7 is started when the power supply device 10 is activated.
First, the contact determination unit 26A determines whether there is contact between the side surfaces 3402 of the battery cells 12 based on the detection results from the pressure sensors 14 (step S10).
If step S10 is negative, the process returns to step S10.
If step S10 is affirmative, the shaking determination means 26B determines whether or not the vehicle is shaking (step S12).
If step S12 is negative, the process returns to step S10.
If step S12 is positive, the control unit 26C notifies the deformation of the battery cell 12 by the notification lamp 22 and the notification buzzer 24 (step S14).
Then, the specifying unit 26E specifies the pressure sensor identification information from the detection result received from the pressure sensor 14, specifies the battery cell identification information from the specified pressure sensor identification information based on the data table of FIG. Store (step S16) and return to step S10.

As described above, according to the present embodiment, the two side surfaces 3404 of the battery cells 12 are in contact with each other by the contact determination unit 26A in a state in which it is determined that the vibration is not generated by the vibration determination unit 26B. When it is determined that the battery cell 12 is deformed, the control means 26C notifies the notification lamp 22 and the notification buzzer 24 that the deformation has occurred.
Therefore, since the determination by the contact determination unit 26A is performed in a state where the possibility that the battery cell 12 is displaced by a force due to acceleration / deceleration or vibration accompanying traveling of the vehicle is low, the deformation of the battery cell 12 can be accurately notified. Is advantageous.
Thus, the driver can drive the vehicle to the repair shop and replace the battery cell 12 by accurately notifying the deformation of the battery cell 12 in this way.

Further, when the shake determination unit 26B determines that the vehicle is not shaken when the shift range detected by the shift position sensor 18 is the parking position, and the vehicle detected by the vehicle speed sensor 16 When it is determined that the vehicle is not shaken when the vehicle speed of the vehicle is zero, the contact determination means 26A is in a state where the vehicle is completely stopped, that is, in a state where the shake of the battery cell 12 is zero. Since the determination is performed, it is advantageous in accurately determining the deformation of the battery cell 12.
In addition, when the shake determination unit 26B determines that the vehicle is not shaken when the acceleration detected by the acceleration sensor 20 is equal to or less than a predetermined threshold, the vehicle is completely stopped. Since the determination by the contact determination means 26A is performed in both the state where the vehicle is traveling and the state where the vehicle is traveling at a constant speed, the frequency of determining the deformation of the battery cell 12 can be increased, and the deformation of the battery cell 12 can be further improved. This is advantageous for early determination.

Further, in the present embodiment, the control unit 26 </ b> C is configured such that when the notification lamp 22 and the notification buzzer 24 notify the deformation of the battery cell 12, the control unit 26 </ b> A The battery cell 12 is specified, and the battery cell identification information of the two specified battery cells 12 is specified.
Therefore, the battery cell 12 that has been deformed can be easily specified based on the specified battery cell identification information, which is advantageous in improving the efficiency of the replacement work of the battery cell 12.

As described above, when the shake determination unit 26B determines that the vehicle is not shaken when the acceleration detected by the acceleration sensor 20 is equal to or less than a predetermined threshold, the vehicle Even when the vehicle is traveling at a constant speed, the determination by the contact determination unit 26A can be performed.
In this case, when it is determined that the two side surfaces 3404 are in contact with each other by the contact determination unit 26A in a state where the vehicle is traveling at a constant speed, and the deformation of the battery cell 12 is notified by the control unit 26C, the vehicle travel mode is changed. You may make it switch to limp form driving | running | working. The limp form travel is a travel mode in which the travel speed of the vehicle is limited to a predetermined regulation speed or less.
If the battery cell 12 is deformed, the performance of the battery cell 12 is lowered, and the battery capacity supplied to the traveling motor may be insufficient.
Therefore, by switching to limp-form travel, it is possible to suppress the power consumption and secure the travel distance of the vehicle, and to replace the battery cell 12 by urgently traveling the vehicle to the repair shop.

  DESCRIPTION OF SYMBOLS 10 ... Power supply device, 12 ... Battery cell, 14 ... Pressure sensor, 16 ... Vehicle speed sensor, 18 ... Shift position sensor, 20 ... Acceleration sensor, 22 ... Notification lamp, 24 ... Notification buzzer, 26 ...... ECU, 26A ... contact determination means, 28B ... swing determination means, 26C .... control means, 26D .... identification means, 26E .... specification means, 28 .... interface, 30 ... electrode body, 32 .... Case: 34... Body part, 3402... Bottom surface, 3404 .. side surface, 3406 .. end face, 36 .. lid part, 35 .. tray, 38.

Claims (6)

A power supply device mounted on a vehicle and comprising a plurality of battery cells,
Battery cells that are arranged so that the side surfaces face each other at an interval;
Contact determination means for determining that the side surfaces of the adjacent battery cells are in contact with each other;
Shaking determination means for determining that the vehicle is not shaking;
Informing means for informing that deformation has occurred in the battery cell when the contact determining means determines that the two side surfaces of the battery cell are in contact with each other;
With
The power supply apparatus according to claim 1, wherein the notification unit is activated when it is determined by the shaking determination unit that no shaking has occurred. A pressure sensor is attached to the approximate center of each battery cell side surface of the plurality of battery cells,
The contact determination means determines contact between the two side surfaces based on a detection result of the pressure sensor;
The power supply device according to claim 1. The shake determining means determines that the vehicle is not shaken when a shift range of the vehicle is a parking position;
The power supply device according to claim 1 or 2, wherein The shake determination means determines that the vehicle is not shaken when the vehicle speed is zero;
The power supply device according to claim 1 or 2, wherein The shake determination means determines that the vehicle is not shaken when an acceleration detected by an acceleration sensor provided in the vehicle is equal to or less than a predetermined threshold;
The power supply device according to claim 1 or 2, wherein The power supply device
Identification means for identifying individual battery cells;
The battery cell identified by the identifying means comprises a specifying means for specifying a battery cell that has been contact-determined by the contact determining means,
The power supply device according to any one of claims 1 to 5.

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