JP6287637B2 - Battery module - Google Patents

Description

  The present invention relates to a battery module.

  Conventionally, a battery module in which a plurality of battery cells such as lithium ion secondary batteries are arranged is known. In such a battery module, for example, when an abnormality such as an overcurrent state occurs due to deterioration of the battery cell or malfunction of the connected device, a high-temperature gas may be generated inside the battery cell due to a rapid progress of the battery reaction. is there.

  For such a problem, a technique for preventing overcharging of the battery module when an abnormality of the battery cell is detected is used. For example, in the battery pack described in Patent Document 1, a protection circuit board having various elements such as a protection IC element, an FET element, and a PTC element is resin-molded together with a unit cell. In this pack battery, the protection IC element mounted on the protection circuit board detects the state of the unit cell, and stops power supply to the unit cell from the outside, for example, when overcharge occurs.

JP 2010-198769 A

  By the way, each battery cell constituting the battery module is provided with an open valve for releasing the gas to the outside of the case in order to prevent an increase in the case internal pressure when a high temperature gas is generated in the battery cell due to an abnormality. There is a case. In this case, if the high-temperature gas released from the open valve directly hits the substrate in the battery module, the element may not operate normally due to the influence of heat on the substrate. If it does so, abnormality may not be detected appropriately at the time of abnormality of a battery cell, and there exists a possibility that the electric power feeding to a battery cell from the outside cannot be stopped.

  An aspect of the present invention has been made to solve the above-described problem, and an object of the present invention is to provide a battery module that can protect a monitoring substrate from a high-temperature gas generated when a battery cell is abnormal.

  In order to solve the above problems, a battery module according to an aspect of the present invention is a battery module in which a plurality of battery cells are arranged, and for monitoring in which a state detection device that receives information indicating the state of the battery module is mounted. And a switching board on which a switching element for switching power supply to the battery cell from the external device based on information indicating the state of the battery module is mounted. The battery cell includes a gas in the battery cell. The switching substrate is disposed between the battery cell and the monitoring substrate so as to face at least the opening valve.

  In this battery module, the switching substrate is disposed between the battery cell and the monitoring substrate so as to face at least the open valve. Therefore, even when a high-temperature gas is released from the release valve when the battery cell is abnormal, it is possible to prevent the high-temperature gas from directly hitting the monitoring substrate by the switching substrate. Therefore, in this battery module, the monitoring substrate can be protected from high-temperature gas.

  The switching substrate may be disposed on a heat resistant member having heat resistance against the gas. Thereby, since a heat resistant member is further arrange | positioned between a battery cell and the monitoring board | substrate, the monitoring board | substrate can be protected more suitably.

  The monitoring substrate may be erected on the heat resistant member via the spacer member. Thereby, since the monitoring substrate is disposed apart from the switching substrate and the heat resistant member, heat conduction from the switching substrate and the heat resistant member to the monitoring substrate can be suppressed.

  According to one aspect of the present invention, the monitoring substrate can be protected from high-temperature gas generated when the battery cell is abnormal.

It is sectional drawing which shows one Embodiment of the battery module which concerns on this invention. It is a perspective view which shows the battery cell which comprises the battery module shown in FIG. It is sectional drawing which shows the internal structure of the battery cell shown in FIG. It is sectional drawing which shows the effect | action of the battery module which concerns on a comparative example. It is sectional drawing which shows the effect | action of the battery module shown in FIG.

  Hereinafter, preferred embodiments of a battery module according to the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a cross-sectional view showing an embodiment of a battery module according to the present invention. As shown in FIG. 1, the battery module 1 includes a hollow casing 2 having a substantially rectangular parallelepiped shape, for example, and a plurality of battery cells 3 accommodated in the casing 2. The plurality of battery cells 3 are arranged so as to be connected to each other in series, for example.

  FIG. 2 is a perspective view showing the battery cell 3 constituting the battery module 1 shown in FIG. 3 is a cross-sectional view showing an internal configuration of the battery cell 3 shown in FIG. The battery cell 3 is configured as an in-vehicle non-aqueous electrolyte secondary battery such as a lithium ion secondary battery. The battery cell 3 includes, for example, a hollow case 31 having a substantially rectangular parallelepiped shape and an electrode assembly 32 accommodated in the case 31.

  The case 31 includes, for example, a bottomed battery case can 33 whose one side is open, and a lid portion 34 provided so as to close the opening of the battery case 33. A positive electrode terminal 35 and a negative electrode terminal 36 are spaced apart from each other on the lid 34. The positive electrode terminal 35 is fixed to the lid portion 34 via an insulating ring 37, and the negative electrode terminal 36 is fixed to the lid portion 34 via an insulating ring 38. Further, for example, an opening valve 39 that opens the gas in the case 31 to the outside when the internal pressure of the case 31 exceeds a predetermined pressure is provided at a substantially central portion of the lid portion 34. The case 31 is filled with, for example, a non-aqueous electrolyte solution 40.

  The electrode assembly 32 includes, for example, a positive electrode (not shown), a negative electrode 41, and a bag-like separator (not shown) disposed between the positive electrode and the negative electrode 41. In the electrode assembly 32, the positive electrode is accommodated in the separator, and in this state, the positive electrode and the negative electrode 41 are alternately stacked via the separator.

  The positive electrode has, for example, a metal foil made of an aluminum foil and a positive electrode active material layer formed on both surfaces of the metal foil. The positive electrode active material layer is formed including a positive electrode active material and a binder. Examples of the positive electrode active material include composite oxide, metallic lithium, and sulfur. The composite oxide includes, for example, at least one of manganese, nickel, cobalt, and aluminum and lithium. A tab 42 is formed on the upper edge of the positive electrode corresponding to the position of the positive electrode terminal 35. The tab 42 extends upward from the upper edge portion of the positive electrode and is connected to the positive electrode terminal 35 via the conductive connection member 43.

  On the other hand, the negative electrode 41 includes, for example, a metal foil made of copper foil and a negative electrode active material layer formed on both surfaces of the metal foil. The negative electrode active material layer is formed including a negative electrode active material and a binder. Examples of the negative electrode active material include carbon such as graphite, highly oriented graphite, mesocarbon microbeads, hard carbon, and soft carbon, alkali metals such as lithium and sodium, metal compounds, SiOx (0.5 ≦ x ≦ 1.5 ) And the like, and boron-added carbon. A tab 44 is formed on the upper edge of the negative electrode 41 in correspondence with the position of the negative electrode terminal 36. The tab 44 extends upward from the upper edge portion of the negative electrode 41 and is connected to the negative electrode terminal 36 via a conductive connection member 45.

  The separator is formed in a bag shape, for example, and contains only the positive electrode inside. Examples of the material for forming the separator include a porous film made of a polyolefin resin such as polyethylene (PE) and polypropylene (PP), a woven fabric or a non-woven fabric made of polypropylene, polyethylene terephthalate (PET), methylcellulose and the like. In addition, a separator is not restricted to a bag shape, You may use a sheet-like thing.

  As shown in FIG. 1, the battery module 1 further includes a monitoring substrate 4, a switching substrate 5, and a heat resistant member 6 in the housing 2.

  In the monitoring substrate 4, a state detection device 8 that receives information indicating the state of the battery module 1 (current value, voltage value, temperature, temperature inside the housing, temperature outside the housing, etc. of the battery cell 3) is mounted on the substrate 7. ing. The monitoring substrate 4 of this embodiment is assumed to receive temperature information of the battery module 1. The substrate 7 is made of, for example, a glass epoxy resin.

  The state detection device 8 of the present embodiment transmits the received temperature information of the battery module 1 to a monitoring ECU (not shown). Based on the temperature information received from the state detection device 8, the monitoring ECU transmits to the switching substrate 5 a control signal for controlling the switching element 10 mounted on the switching substrate 5 described later.

  In the switching substrate 5, the switching element 10 is mounted on the substrate 9. The substrate 9 is made of, for example, a glass epoxy resin. The switching element 10 is provided between the battery cell 3 and an external device (not shown). Based on the information indicating the state of the battery module 1, the switching element 10 supplies power to the battery cell 3 and stops power supply. It is to switch. The switching element 10 of this embodiment is a MOSFET, for example, and is turned on / off based on a signal from the monitoring ECU. When the switching element 10 is turned on, power is supplied from the external device to the battery cell 3.

  The heat-resistant member 6 is formed of a material that has heat resistance to a gas that is opened from the open valve 39 of the battery cell 3 when an abnormality occurs (for example, a resin material that has a melting temperature higher than the temperature of the gas). The heat resistant member 6 is attached to the side wall of the housing 2 by, for example, a restraining member so as to face each open valve 39 of each battery cell 3.

  For example, the monitoring substrate 4 is erected on the surface of the heat-resistant member 6 opposite to the battery cell 3 via the spacer member 11. The switching substrate 5 is disposed, for example, on the surface of the heat resistant member 6 opposite to the battery cell 3 via the spacer member 12 so as to face each open valve 39 of each battery cell 3. The spacer members 11 and 12 are made of, for example, the same material as that forming the heat-resistant member 6. Thus, in the battery module 1, the switching substrate 5 and the heat-resistant member 6 are arranged between each battery cell 3 and the monitoring substrate 4 so as to face each open valve 39 of the battery cell 3. Yes.

  Hereinafter, the function and effect of the battery module 1 will be described. First, a battery module according to a comparative example will be described. FIG. 4 is a cross-sectional view showing a battery module according to a comparative example. As shown in the figure, the battery module 21 includes a plurality of battery cells 3 accommodated in the housing 2 and a monitoring substrate 4. The battery module 21 does not include the switching substrate 5, but the switching substrate 5 is virtually shown in FIG.

  In the battery module 21, for example, when an abnormality occurs in the battery cell 3 and the high-temperature gas G is released from the release valve 39, the switching substrate 5 is disposed between the release valve 39 and the monitoring substrate 4. Therefore, the high-temperature gas G directly hits the state detection device 8 (the monitoring substrate 4). As a result, the state detection device 8 (the monitoring substrate 4) may not operate normally due to the influence of heat. Therefore, the battery module 21 may not be able to properly detect the abnormality.

  FIG. 5 is a cross-sectional view showing the operation of the battery module 1 of the present embodiment. As shown in the figure, in the battery module 1, for example, when an abnormality occurs in the battery cell 3 and the high-temperature gas G is released from the release valve 39, the heat-resistant member 6 faces each release valve 39. Since each battery cell 3 and the monitoring substrate 4 are arranged, the high temperature gas G can be prevented from directly hitting the monitoring substrate 4. Further, a switching substrate 5 is disposed between each battery cell 3 and the monitoring substrate 4 so as to face each open valve 39. Therefore, for example, even when the heat-resistant member 6 is damaged by the high temperature gas G, the switching substrate 5 can prevent the high temperature gas G from directly hitting the monitoring substrate 4. Therefore, in the battery module 1, the monitoring substrate 4 can be protected from the high-temperature gas G generated when the battery cell 3 is abnormal, so that the abnormality of the battery module 1 is appropriately detected. Even if the switching substrate 5 does not operate normally due to the high-temperature gas G, the monitoring substrate 4 operates normally. For example, the monitoring ECU sends detection information regarding abnormality detection from the monitoring substrate 4. It can be received and the abnormality of the battery module 1 can be grasped appropriately.

  In the battery module 1, since the monitoring substrate 4 is erected on the heat-resistant member 6 via the spacer member 11, the monitoring substrate 4 is arranged apart from the switching substrate 5 and the heat-resistant member 6. Will be. For this reason, heat conduction from the switching substrate 5 and the heat-resistant member 6 heated by the high-temperature gas G to the monitoring substrate 4 can be suppressed. Therefore, the influence of heat on the monitoring substrate 4 can be reduced, and normal operation of the monitoring substrate 4 can be suitably ensured.

  The battery module according to the present invention can take other modifications in addition to the above-described embodiment. For example, in the above embodiment, the monitoring substrate 4 is erected on the heat-resistant member 6, but the monitoring substrate 4 may be attached to the side wall of the housing 2 by, for example, a restraining member.

  Moreover, in the said embodiment, although the board | substrate 5 for switching was arrange | positioned through the spacer member 13 in the heat resistant member 6, the board | substrate 5 for switching is directly arrange | positioned in the heat resistant member 6 without a spacer member. May be.

  Moreover, in the said embodiment, although the battery module 1 was equipped with the heat resistant member 6, the battery module 1 does not need to be equipped with the heat resistant member 6. FIG. In this case, the monitoring substrate 4 and the switching substrate 5 are each attached to the side wall of the housing 2 by, for example, a restraining member. Even in this case, since the switching substrate 5 is disposed between each battery cell 3 and the monitoring substrate 4 so as to face each open valve 39, the high-temperature gas G is used for monitoring, as in the above embodiment. Direct contact with the substrate 4 can be prevented. Further, in this case, since the heat resistant member 6 does not need to be provided, the configuration of the battery module 1 can be simplified.

  Moreover, although the state detection apparatus 8 of the said embodiment had the structure which transmits the information which shows the state of the received battery module 1 to monitoring ECU (not shown), it is not restricted to this. For example, the state detection device 8 may transmit a control signal for controlling the switching element 10 mounted on the switching substrate 5 to the switching substrate 5 based on the received information indicating the state of the battery module 1.

  DESCRIPTION OF SYMBOLS 1 ... Battery module, 3 ... Battery cell, 4 ... Monitoring board, 5 ... Switching board, 6 ... Heat-resistant member, 8 ... State detection apparatus, 10 ... Switching element, 11 ... Spacer member, 39 ... Release valve, G …gas.

Claims (3)

A battery module comprising a plurality of battery cells arranged,
A monitoring board on which a state detection device that receives information indicating the state of the battery module is mounted;
A switching board on which a switching element for switching power supply and power supply suspension from an external device based on information indicating the state of the battery module is mounted;
The plurality of battery cells, the monitoring substrate, and the switching substrate are arranged in the same casing,
The battery cell has an open valve that opens the gas in the battery cell to the outside,
The monitoring substrate and the switching substrate are disposed in the gas discharge path released from the release valve,
The battery module is disposed between the battery cell and the monitoring board so that the switching board faces at least the open valve.   The battery module according to claim 1, wherein the switching substrate is disposed on a heat-resistant member having heat resistance to the gas.   The battery module according to claim 2, wherein the monitoring substrate is erected on the heat-resistant member via a spacer member.

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