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EP-4459271-B1 - APPARATUS AND METHOD FOR DIAGNOSING A BATTERY

EP4459271B1EP 4459271 B1EP4459271 B1EP 4459271B1EP-4459271-B1

Inventors

  • KIM, DAE-SOO
  • KIM, YOUNG-DEOK

Dates

Publication Date
20260506
Application Date
20230515

Claims (10)

  1. An apparatus (100) for diagnosing a battery (10), comprising: a discharging unit (110) electrically connected to a battery (10) and configured to discharge the battery (10); an X-ray diffraction analyzing unit (120) configured to output, while the battery (10) is discharging, an X-ray toward a plurality of negative electrode tabs (21) included in the battery (10) and generate a graphite profile for each of the plurality of negative electrode tabs (21) based on the output X-ray; and a control unit (130) configured to determine a charge and discharge behavior of each of the plurality of negative electrode tabs (21) based on the generated plurality of graphite profiles, and diagnose the state of the battery (10) based on the determined plurality of charge and discharge behaviors.
  2. The apparatus (100) for diagnosing a battery (10) according to claim 1, wherein the control unit (130) is configured to determine the charge and discharge behavior of each of the plurality of negative electrode tabs (21) as a charge behavior or a discharge behavior by checking an integrated intensity of graphite in each of the plurality of negative electrode tabs (21) based on the plurality of graphite profiles.
  3. The apparatus (100) for diagnosing a battery (10) according to claim 2, wherein the control unit (130) is configured to determine the charge and discharge behavior of the negative electrode tab (21, 21a-d) in which the integrated intensity decreases as the discharge behavior, and to determine the charge and discharge behavior of the negative electrode tab (21, 21a-d) in which the integrated intensity increases as the charge behavior.
  4. The apparatus (100) for diagnosing a battery (10) according to claim 2, wherein when the discharge behavior is confirmed in the plurality of negative electrode tabs (21), the control unit (130) is configured to diagnose the state of the battery (10) as a normal state, and wherein when the charge behavior is confirmed in at least one of the plurality of negative electrode tabs (21), the control unit (130) is configured to diagnose the state of the battery (10) as an abnormal state.
  5. The apparatus (100) for diagnosing a battery (10) according to claim 4, wherein the control unit (130) is configured to diagnose the state of the negative electrode tab (21, 21a-d) in which the charge behavior is confirmed as a disconnected state.
  6. The apparatus (100) for diagnosing a battery (10) according to claim 1, wherein the X-ray diffraction analyzing unit (120) is configured to output the X-ray in a direction through which the plurality of negative electrode tabs (21) pass.
  7. The apparatus (100) for diagnosing a battery (10) according to claim 1, wherein the X-ray diffraction analyzing unit (120) is configured to output the X-ray in a stacking direction of the plurality of negative electrode tabs (21).
  8. The apparatus (100) for diagnosing a battery (10) according to claim 1, wherein the X-ray diffraction analyzing unit (120) is configured to determine an integrated intensity of graphite for each of the plurality of negative electrode tabs (21) based on diffraction information of the X-ray whenever the X-ray is output, and to generate the graphite profile representing the correspondence between time and the integrated intensity for each the plurality of negative electrode tabs (21).
  9. A battery test device, comprising the apparatus (100) for diagnosing a battery (10) according to any one of claims 1 to 8.
  10. A method for diagnosing a battery (10), comprising: a discharging step of discharging a battery (10); an X-ray outputting step of outputting, while the battery (10) is discharging, an X-ray toward a plurality of negative electrode tabs (21) included in the battery (10); a graphite profile generating step of generating a graphite profile for each of the plurality of negative electrode tabs (21) based on the output X-ray; a charge and discharge behavior determining step of determining a charge and discharge behavior of each of the plurality of negative electrode tabs (21) based on the plurality of graphite profiles generated in the graphite profile generating step; and a battery state diagnosing step of diagnosing the state of the battery (10) based on the determined plurality of charge and discharge behaviors.

Description

TECHNICAL FIELD The present application claims priority to Korean Patent Application No. 10-2022-0066560 filed on May 31, 2022 in the Republic of Korea. The present disclosure relates to an apparatus and method for diagnosing a battery, and more particularly, to an apparatus and method for diagnosing a battery, which is capable of diagnosing whether an internal tab is disconnected. BACKGROUND ART Recently, the demand for portable electronic products such as notebook computers, video cameras and portable telephones has increased sharply, and electric vehicles, energy storage batteries, robots, satellites and the like have been developed in earnest. Accordingly, high-performance batteries allowing repeated charging and discharging are being actively studied. Batteries commercially available at present include nickel-cadmium batteries, nickel hydrogen batteries, nickel-zinc batteries, lithium batteries and the like. Among them, the lithium batteries are in the limelight since they have almost no memory effect compared to nickel-based batteries and also have very low self-charging rate and high energy density. In general, a battery has a structure in which a positive electrode material, a separator, and a negative electrode material are stacked in parallel. Here, a positive electrode tab is connected to each of the plurality of positive electrode materials, and the plurality of positive electrode tabs may be electrically connected to each other through a positive electrode lead. Similarly, a negative electrode tab is connected to each of the plurality of negative electrode materials, and the plurality of negative electrode tabs may be electrically connected to each other through a negative electrode lead. For example, there is a high possibility that disconnection occurs in the electrode tabs (positive electrode tab and negative electrode tab) of the battery. Since the positive electrode tab and the negative electrode tab are made of a very thin metal film like a positive electrode plate and a negative electrode plate, there is a high probability of being disconnected before other components when an impact is applied to the secondary battery. If at least one positive electrode tab or at least one negative electrode tab is damaged and disconnected, battery performance may deteriorate and an accident such as fire or explosion may occur. Therefore, it is necessary to develop a technology capable of accurately diagnosing whether the internal tab of the battery is disconnected. KR 20210053748 A discloses: Provided is a method of predicting a lifespan characteristic of a secondary battery including a carbon-based hybrid negative electrode. The method includes: measuring a lattice spacing (d-spacing) of a carbon-based negative electrode active material of a target carbon-based hybrid negative electrode by using an X-ray diffractometer to plot a variation of a lattice spacing value according to a charging/discharging capacity (X-axis) as a graph during charging and discharging of a target secondary battery including the target carbon-based hybrid negative electrode including the carbon-based negative electrode active material and a non-carbon-based negative electrode active material; calculating a target gradient difference that is a difference between gradient values changed with respect to an inflection point of the graph during the discharging in the plotted graph; comparing the target gradient difference with a reference gradient difference that is a difference between gradient values with respect to an inflection point in a graph showing a variation of a lattice spacing value according to a charging/discharging capacity (X-axis) of a reference secondary battery; and predicting whether a lifespan characteristic of the target secondary battery is improved as compared with the reference secondary battery from a comparison result. Accordingly, the life characteristic is improved. DISCLOSURE Technical Problem The present disclosure is designed to solve the problems of the related art, and therefore the present disclosure is directed to providing an apparatus and method for diagnosing a battery, which is capable of accurately diagnosing whether an internal tab of the battery is disconnected. These and other objects and advantages of the present disclosure may be understood from the following detailed description and will become more fully apparent from the exemplary embodiments of the present disclosure. Also, it will be easily understood that the objects and advantages of the present disclosure may be realized by the means shown in the appended claims and combinations thereof. Technical Solution The invention is set out in the appended claims. An apparatus for diagnosing a battery according to one aspect of the present disclosure comprises: a discharging unit electrically connected to a battery and configured to discharge the battery; an X-ray diffraction analyzing unit configured to output, while the battery is discha