JP2014182970A - Abnormality detection device for battery and abnormality detection method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an abnormality detection device and an abnormality detection method of improving accuracy in abnormality detection of a battery.SOLUTION: An electrode laminate 11 which is formed by laminating a positive electrode plate and a negative electrode plate, and an electrolyte are encapsulated within an insulative outer package 10, and electrode terminals 12 of positive and negative electrodes electrically connected to the electrode laminate 11 via a lead part 13 are partially led outside of the outer package 10. Before encapsulating the electrolyte, air within the outer package 10 is sucked and the outer package 10 is adhered to at least the lead part 13. In such an adhered state, a voltage is applied to a battery and by detecting the voltage or a resistance value, abnormality of the battery is detected.

Description

  The present invention relates to a battery abnormality detection device and a battery abnormality detection method in which an electrode laminate and an electrolytic solution are enclosed in an exterior body.

  As described in Patent Document 1, an electrode laminate in which positive and negative electrode plates are alternately laminated is enclosed with an electrolytic solution in an insulating outer body formed of a laminate film, and the lead portion is interposed therebetween. A laminate type battery in which a part of electrode terminals connected to the electrode laminate is led out of the exterior body is known.

JP 2008-243439 A

  In such a battery, if foreign matter (contamination) such as dust is mixed in the exterior body, there is a risk of causing a short circuit or the like. Therefore, a continuity test that detects battery abnormality before product shipment. Is done. Specifically, after pressing the exterior body containing the electrode laminate from both sides, a voltage is applied to the battery, and the presence or absence of abnormality is diagnosed by detecting the voltage and resistance value.

  However, even if the exterior body is pressed from both sides, a hollow portion (space) is inevitably generated inside the exterior body. In particular, the lead portion composed of a plurality of leads that electrically connect each positive electrode plate / negative electrode plate of the electrode laminate and the electrode terminal thereof is changed from a thick electrode laminate having a large size in the plate pressure direction to a thin electrode terminal. A hollow portion is likely to be formed between the lead portion and the exterior body because of the complicated shape in which the dimension in the plate thickness direction gradually decreases toward.

  When the above continuity test is performed in such a situation where a hollow portion is generated, an abnormality cannot be detected even if there is foreign matter in the hollow portion, and it is mistaken for a normal product despite the presence of foreign matter. There is a risk of judging.

  The present invention has been made in view of such circumstances, and an object thereof is to improve the accuracy of battery abnormality detection.

  The battery according to the present invention encloses an electrode laminate formed by laminating a positive electrode plate and a negative electrode plate and an electrolyte in an insulating exterior body, and leads the electrode laminate via a lead portion. A part of the electrode terminals of the positive electrode and the negative electrode which are electrically connected are led out of the outer package.

  In the battery abnormality detection device according to the present invention, before the electrolytic solution is sealed in the exterior body in which the electrode laminate is disposed, air in the exterior body is sucked to at least lead the exterior body. Detecting an abnormality in the battery by applying a voltage to the battery and detecting the voltage or resistance value in a state where the suction means is in close contact with the part, and the exterior body and the lead part are in close contact with the suction means. And an anomaly detecting means.

  Preferably, the suction means presses the exterior body against the lead portion and sucks air in the exterior body to bring the exterior body into close contact with the lead portion.

  Further, the battery abnormality detection method according to the present invention includes at least leading the exterior body by sucking air in the exterior body before enclosing the electrolyte in the exterior body in which the electrode laminate is disposed. A suction step for tightly contacting the part, and an abnormality detecting step for detecting an abnormality of the battery by applying a voltage to the battery and detecting the voltage or resistance value in a state where the exterior body is in close contact with the lead part. And an injection step of injecting an electrolytic solution into the exterior body in which the electrode laminate is disposed, and a sealing step of sealing a peripheral portion of the exterior body into which the electrolytic solution has been injected. Yes.

  According to the present invention, before the electrolytic solution is sealed in the exterior body in which the electrode laminate is arranged, the exterior body and the exterior body It is possible to suppress or avoid the formation of a hollow portion between the lead portion. As a result, it is possible to suppress and avoid an erroneous determination in which the foreign matter present in the cavity is determined to be normal without being detected, and the detection accuracy of abnormality detection can be improved.

Explanatory drawing which illustrates the aspect at the time of performing abnormality detection of a battery using the abnormality detection apparatus of the battery which concerns on one Example of this invention. The top view which shows the battery of the said Example. 3 (a) is an enlarged cross-sectional view showing the main part of the battery of the above embodiment, FIG. 3 (b) is an enlarged cross-sectional view of part B of FIG. 3 (a), and FIG. 3 (c) is FIG. The expanded sectional view of the C section of a). The flowchart which shows the flow of the abnormality detection process of a present Example. Explanatory drawing which illustrates notionally the aspect at the time of performing battery abnormality detection using the battery abnormality detection apparatus which concerns on a comparative example.

  Hereinafter, the present invention will be described with reference to illustrated embodiments. FIG. 1 is an explanatory diagram conceptually illustrating an aspect when battery abnormality detection is performed using a battery abnormality detection device according to an embodiment of the present invention.

  An abnormality detection target battery is a laminate type battery using a laminate film in which both surfaces of a metal layer are covered with an insulating layer as an exterior body, and will be described in detail later by exemplifying a specific structure. An electrode laminate 11 is encapsulated with an electrolyte in a laminate film 10, and a positive electrode / negative electrode current collector tab 12 (12A, 12B) serving as an electrode terminal partially led to the outside has a large number of positive electrodes / negative electrodes. It is electrically connected to the electrode laminate 11 via a lead portion 13 made of a lead (wire).

  This battery will be described in detail with reference to FIG. 2 and FIG. Here, FIG. 2 is a plan view of the whole battery, FIG. 3 (a) is an enlarged cross-sectional view showing the main part of the battery, FIG. 3 (b) is an enlarged cross-sectional view of part B of FIG. 3 (a), FIG.3 (c) is an expanded sectional view of the C section of Fig.3 (a).

  First, the overall structure will be described. The battery includes an electrode laminated body 11 as a power generation element, and this electrode laminated body 11 is disposed at the center of a laminate film 10 constituting an outer package of the battery. The electrode laminate 11 is welded over the entire periphery of the outer edge portion of the electrode laminate 11 so as to be sandwiched between the laminate films 10 in the plate pressure direction and sealed together with an electrolyte (not shown). Yes.

  Next, as shown in FIG. 3C, the electrode laminate 11 is configured by laminating a plurality of positive plates 14 and negative plates 15 alternately with separators 16 for short circuit suppression. The planar shape is substantially rectangular. The positive electrode plate 14 is obtained by applying a positive electrode active material on both surfaces of a sheet-like positive electrode current collector 17, and the negative electrode plate 15 is obtained by applying a negative electrode active material on both surfaces of a sheet-like negative electrode current collector 18. is there. Each positive electrode plate 14 is connected to a positive electrode tab 12A as a positive electrode terminal via a positive electrode lead (wire). Each negative electrode plate 15 is connected to a negative electrode tab 12B (not shown in FIG. 3) as a negative electrode terminal via a negative electrode lead.

  The positive electrode lead and the negative electrode lead are each formed of a metal foil. Specifically, for example, the positive electrode lead is formed from an aluminum foil, and the negative electrode lead is formed from a copper foil. And each positive electrode lead withdraw | derived from each positive electrode plate is piled up mutually in layers, and is joined to the positive electrode tab 12A by methods, such as welding. In addition, the respective negative electrode leads drawn from the respective negative electrode plates are laminated in layers and joined to the negative electrode tab 12B by a technique such as welding. The positive electrode lead is formed by extending the positive electrode current collector 17 to the positive electrode tab 12A. Similarly, the negative electrode lead is formed by extending the negative electrode current collector 18 to the negative electrode tab 12B.

  The positive electrode tab 12A and the negative electrode tab 12B are each formed of a metal plate. Specifically, for example, the positive electrode tab 12A is formed from an aluminum plate, and the negative electrode tab 12B is formed from a nickel plate. Then, the positive electrode tab 12A and the negative electrode tab 12B are pulled out from the edge on one short side of the battery exterior and function as a positive electrode terminal and a negative electrode terminal.

  Further, as shown in FIG. 3B, the laminate film 10 constituting the battery exterior has, for example, an aluminum alloy layer 10A as a base material, and PE (polyethylene) or PP (polypropylene) inside the aluminum alloy layer 10A. A polymer resin layer 10B made of, for example, is coated. The laminate film 10 has a protective layer 10D made of nylon or the like bonded to the outside of the aluminum alloy layer 10A via an adhesive layer 10C. Further, in a region corresponding to the tab 12 in the welded portion, a resin film 19 such as polypropylene is interposed on both surfaces of each tab 12 from the viewpoint of improving the sealing performance.

  An example of the production of such a battery will be described. The positive electrode plate 14 and the negative electrode plate 15 are alternately arranged while the separator 16 is interposed between the negative electrode plate 15 and the positive electrode plate 14 so that the negative electrode plate 15 is the outermost part. Thus, the electrode laminate 11 is produced. The number of stacked electrode plates is set to a value that provides a predetermined battery capacity (for example, 2 [Ah]). Next, an aluminum positive electrode tab 12A is joined to the lead portion 13 of the electrode laminate 11 by ultrasonic welding. Similarly, the negative electrode tab 12B made of nickel is joined to the lead portion 13 of the electrode laminate 11 by ultrasonic welding.

  Next, after the electrode tab 12A and the negative electrode tab 12B welded to the electrode group are accommodated in a pair of laminate films 10, the film periphery is a total of three sides, two sides on the short side and one side on the long side. Is welded by heat sealing. At this time, the pair of laminate films 10 has a cup shape provided with a recess to accommodate the electrode group, and has a shape in which the positive electrode tab 12A and the negative electrode tab 12B are led out from one side of the short side, respectively. . The laminate film 10 has, for example, a three-layer structure of a nylon layer as a protective layer 10D, an aluminum alloy layer 10A as a metal layer, and a polypropylene resin layer as a polymer resin layer 10B from the outside of the battery. used.

  Thus, before the electrode laminated body 11 which laminated | stacked the positive electrode plate 14 and the negative electrode plate 15 on the inside of the laminate film 10 is accommodated, and inject | pouring electrolyte solution, the abnormality detection process mentioned later is implemented. And, in the state where there is no abnormality by this abnormality detection processing, that is, it is determined to be normal, after injecting the electrolytic solution from the opening (non-welded long side) of the laminate film 10, The battery is manufactured by welding the opening.

  As shown in FIG. 1, the battery abnormality detection device of this embodiment includes a measuring instrument 21 and measurement terminals 22 and 23. The measuring instrument 21 includes at least a power source for applying a DC voltage or an AC voltage between the metal layer of the laminate film 10 and one electrode terminal (for example, the negative electrode tab 12B), and a metal of the laminate film 10 when the voltage is applied. Resistance measuring means for measuring a resistance value (or voltage) between the electrode layer and one electrode terminal (for example, the negative electrode tab 12B), a defect in the insulating layer of the laminate film 10, a short circuit of the battery, etc. based on the measured resistance value Abnormality detecting means for detecting / determining whether or not there is any abnormality.

  Next, with reference to FIG.4 and FIG.5, the abnormality detection process of the battery which makes the principal part of a present Example is demonstrated. In the state before the electrode laminate 11 in which the positive electrode plates 14 and the negative electrode plates 15 are alternately laminated is accommodated in the laminate film 10 and before the electrolyte solution is injected, as shown in FIG. Even if it is pressed from both sides, the cavity 24 is unavoidably generated inside. In particular, in the portion of the lead portion 13 connecting the tab 12 and the electrode laminate 11, the electrode laminate 11 has a larger plate pressure direction dimension than the tab 12 or the electrode laminate 11 having a flat shape. Due to the complicated shape in which the dimension in the plate pressure direction gradually decreases toward the thin tab 12, the hollow portion 24 is inevitably easily formed. When the abnormality detection process is performed in such a situation where the cavity portion 24 remains, it cannot be detected even if there is a foreign substance in the cavity portion 24, and it is erroneously determined as a normal product although it is actually a defective product. There is a risk of being.

  Therefore, in the present embodiment, in the suction process of step S11 in FIG. 4, the air in the laminate film 10 is sucked before injecting the electrolyte into the laminate film 10 in which the electrode laminate 11 is accommodated. The hollow portion 24 is eliminated by being elastically deformed and closely contacting the flat tab 12 and the electrode laminate 11 as well as the lead portion 13 having a complicated three-dimensional shape without a gap.

  At this time, the laminate film 10 is pressed against the inner side in which the tabs 12 and the electrode laminate 11 are accommodated from both sides, and the air in the laminate film 10 is sucked in order to bring the laminate film 10 into contact with each other more securely. You may make it closely_contact | adhere to the lead | read | reed part 13 grade | etc.,.

  In the subsequent inspection process of step S12, a voltage is applied to the battery while the laminate film 10 is in close contact with the lead portion 13 and the like, and the abnormality of the battery due to a short circuit or the like is detected by detecting the voltage or resistance value. . Since the abnormality detection method itself is well-known, detailed description is omitted here. For example, if a threshold value of a voltage value or a resistance value for determining the presence or absence of an abnormality (defect) is set in advance and the threshold value is exceeded, The product is determined to be a non-defective product if the product is below the threshold value.

  Then, as described above, the electrolyte solution is injected into the laminate film 10 in the electrolyte solution injection process in step S13 for the normal product that has not been determined to be abnormal. In the subsequent sealing step of Step S14, the peripheral edge of the laminate film 10 into which the electrolytic solution has been injected is sealed to manufacture a battery.

  As described above, according to the present embodiment, it is possible to suppress / avoid the formation of the cavity portion 24 in the lead portion 13 and the like by providing the suction step of Step S1. As a result, it is possible to suppress / avoid erroneous determination that is determined to be normal without detecting foreign matter adhering to the hollow portion, and it is possible to improve determination accuracy of abnormality detection.

  As described above, the present invention has been described based on the specific embodiments. However, the present invention is not limited to the above-described embodiments, and includes various modifications and changes. For example, in the above embodiment, both the two tabs which are electrode terminals are led out from the edge on one short side of the rectangular battery, but the electrode terminals are connected to the respective short side edges of the battery. You may comprise so that it may pull out outside from an edge.

10 ... Laminate film (exterior body)
11 ... Electrode laminated body 12 ... Tab (electrode terminal)
DESCRIPTION OF SYMBOLS 13 ... Lead part 14 ... Positive electrode plate 15 ... Negative electrode plate 16 ... Separator 21 ... Measuring instrument 22, 23 ... Measurement terminal 24 ... Hollow part

Claims (3)

A positive electrode plate in which an electrode laminate formed by laminating a positive electrode plate and a negative electrode plate and an electrolytic solution are enclosed in an insulating exterior body and electrically connected to the electrode laminate via a lead portion And a battery abnormality detection device in which part of the electrode terminal of the negative electrode is led out of the exterior body,
A suction means for sucking the air in the outer package before adhering the electrolytic solution into the outer package in which the electrode laminate is disposed, and for bringing the outer package into close contact with at least the lead part;
An abnormality detecting means for detecting an abnormality of the battery by applying a voltage to the battery in a state where the exterior body and the lead part are in close contact with each other by the suction means, and detecting the voltage or the resistance value;
A battery abnormality detection device comprising:   2. The battery abnormality detection device according to claim 1, wherein the suction unit presses the exterior body against the lead portion and sucks air in the exterior body to bring the exterior body into close contact with the lead portion. . A positive electrode plate in which an electrode laminate formed by laminating a positive electrode plate and a negative electrode plate and an electrolytic solution are enclosed in an insulating exterior body and electrically connected to the electrode laminate via a lead portion And a battery abnormality detection method in which a part of the electrode terminal of the negative electrode is led out of the exterior body,
A suction step of sucking the air in the outer package before adhering the electrolytic solution inside the outer package in which the electrode laminate is disposed, and bringing the outer package into close contact with at least the lead part;
An abnormality detection step of detecting an abnormality of the battery by applying a voltage to the battery and detecting a voltage or a resistance value in a state where the exterior body and the lead part are in close contact with each other.
An injection step of injecting an electrolyte into the exterior body in which the electrode laminate is disposed;
A sealing step of sealing the peripheral portion of the outer package into which the electrolyte solution has been injected;
A battery abnormality detection method characterized by comprising:

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