Apparatus and Method for Battery Abnormal Condition Prediction, and Battery Management System Providing the Same Method

Abstract

An apparatus and method to detect an abnormal behavior of a battery, including a receiving portion receiving information indicating a temperature value, a pressure value, and a gas concentration value respectively from a temperature sensor measuring temperature inside a battery module, a pressure sensor measuring pressure inside the battery module, and a gas sensor measuring gas concentration inside the battery module, a comparison portion comparing the temperature value, the pressure value, and the gas concentration value with first, second, and third threshold values, respectively, and a detection portion determining occurrence of abnormal behavior of the battery when the comparison result shows the pressure value exceeding the second threshold value falling below the second threshold value or the gas concentration value exceeding the third threshold value, while the temperature value exceeds the first threshold value.

Claims

1. A battery abnormal condition prediction apparatus that detects an abnormal behavior of a battery, comprising: a receiving portion configured to receive information indicating a temperature value from a temperature sensor that measures a temperature inside a battery module, a pressure value from a pressure sensor that measures a pressure inside the battery module, and a gas concentration value from a gas sensor that measures a gas concentration inside the battery module; a comparison portion configured to compare the temperature value, the pressure value, and the gas concentration value with a first threshold value, a second threshold value, and a third threshold value, respectively; and a detection portion configured to determine occurrence of an abnormal behavior of the battery in response to at least one of: the pressure value falling from above the second threshold value to below the second threshold value; or the gas concentration value exceeding the third threshold value, while the temperature value exceeds the first threshold value.

2. A battery abnormal condition prediction apparatus that detects an abnormal behavior of a battery, comprising: a receiving portion configured to receive information indicating a first voltage from a temperature sensor corresponding to a temperature inside a battery module, a second voltage from a pressure sensor corresponding to a pressure inside the battery module, and a third voltage from a gas sensor corresponding to a gas concentration inside the battery module; a first comparator configured to compare the first voltage with a first threshold voltage; a second comparator configured to compare the second voltage with a second threshold voltage; a third comparator configure to compare the third voltage with a third threshold voltage; and a detection portion configured to determine occurrence of an abnormal behavior in the battery in response to at least one of: a level change in an output signal of the second comparator; or a level change in an output signal of the third comparator and an output signal of the first comparator when the first voltage is higher than the first threshold voltage.

3. The battery abnormal condition prediction apparatus of claim 2, wherein the detection portion is configured to detect occurrence of thermal runaway in the battery in response to the output signal of the second comparator when the second voltage is lower than the second threshold voltage and the output signal of the first comparator when the first voltage is higher than the first threshold voltage.

4. The battery abnormal condition prediction apparatus of claim 2, wherein the detection portion is configure to detect occurrence of thermal runaway in the battery in response to the output signal of the third comparator when the third voltage is higher than the third threshold voltage and the output signal of the first comparator when the first voltage is higher than the first threshold voltage.

5. The battery abnormal condition prediction apparatus of claim 2, wherein the detection portion is configured to determine occurrence of an electrolyte solution leakage of the battery in response to the output signal of the third comparator when the third voltage is higher than the third threshold voltage.

6. (canceled)

7. A method for predicting an abnormal behavior of a battery, comprising: receiving information that indicates a first voltage from a temperature sensor corresponding to a temperature inside a battery module, a second voltage from a pressure sensor corresponding to a pressure inside the battery module, and a third voltage from a gas sensor corresponding to a gas concentration inside the battery module; outputting, by a first comparator, either a high level signal when the first voltage is higher than a first predetermined threshold voltage or a low level signal when the first voltage is not higher than the first predetermined threshold voltage; outputting, by a second comparator, either a high level signal when the second voltage is higher than a second threshold voltage, or a low level signal when the second voltage is lower than the second threshold voltage; outputting, by a third comparator, either a high level signal when the third voltage is higher than a third threshold voltage, or a low level signal when the third voltage is lower than the third threshold voltage; and determining occurrence of an abnormal behavior in the battery based on output signals of the first comparator, the second comparator, and the third comparator.

8. The method for predicting the abnormal behavior of the battery of claim 7, wherein determining occurrence of the abnormal behavior in the battery comprises determining occurrence of thermal runaway of the battery in response to the first comparator outputting the high level signal and the second comparator changing to the low level signal from the high level signal.

9. The method for predicting the abnormal behavior of the battery of claim 7, wherein determining occurrence of the abnormal behavior in the battery comprises determining occurrence of thermal runaway of the battery in response to the first comparator outputting the high level signal and the third comparator outputting the high level signal.

10. The method for predicting the abnormal behavior of the battery of claim 7, wherein determining occurrence of the abnormal behavior in the battery comprises determining an electrolyte solution leakage of the battery in response to the third comparator outputting the high level signal.

11. A battery management system including the battery abnormal condition prediction apparatus of claim 1.

12. A battery management system including the battery abnormal condition prediction apparatus of claim 2.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0022] FIG. 1 shows a battery abnormal condition prediction apparatus according to an embodiment.

[0023] FIG. 2 is provided for description of an output signal of a first comparator according to a temperature voltage input according to the embodiment.

[0024] FIG. 3 is provided for description of an output signal of a second comparator according to a pressure voltage input according to the embodiment.

[0025] FIG. 4 is provided for description of an output signal of a third comparator according to a gas voltage input according to the embodiment.

[0026] FIG. 5 is provided for description of an output signal of a first determining portion using the output signals of the first comparator and the second comparator as inputs according to the embodiment.

[0027] FIG. 6 is provided for description of an output signal of a second determining portion using the output signals of the first comparator and the third comparator as inputs according to the embodiment.

[0028] FIG. 7 is a flowchart provided for description of a battery abnormal condition prediction method according to an embodiment.

[0029] FIG. 8 shows a battery system that includes a battery management system providing a battery abnormal condition prediction method according to an embodiment.

DETAILED DESCRIPTION

[0030] Hereinafter, a preferable embodiment of the present invention will be described in more detail with reference to the accompanying drawings. Like reference numerals refer to like elements for easy overall understanding, and a duplicated description of like elements will be omitted. Further, the terms “module” and “unit” which are suffixes for the components used in the specification are granted or mixed by considering only easiness in preparing the specification and do not have meanings or roles distinguished from each other in themselves. Further, in describing the present invention, when it is determined that the detailed description of the publicly known art related to the present invention may obscure the gist of the present invention, the detailed description thereof will be omitted. Further, the accompanying drawings are only for easily understanding the embodiment disclosed in the specification and the technical spirit disclosed in the specification is not limited by the accompanying drawings, and it should appreciated that the accompanying drawings include all changes, equivalents, or substitutions included in the spirit and the technical scope of the present invention.

[0031] Terms including an ordinal number, such as first and second, are used for describing various constituent elements, but the constituent elements are not limited by the terms. The above terms are used only to discriminate one component from the other component.

[0032] It should be understood that, when it is described that an element is “coupled” or “connected” to another element, the element may be “directly coupled” or “directly connected” to the another element or “coupled” or “connected” to the another element through a third element. In contrast, it should be understood that, when it is described that an element is “directly coupled” or “directly connected” to another element, it is understood that no element is present between the element and the another element.

[0033] In this specification, it should be understood that the term “include” or “have” indicates that a feature, a number, a step, an operation, a component, a part, or a combination thereof described in the specification is present, but does not exclude a possibility of presence or addition of one or more other features, numbers, steps, operations, components, parts or combinations, in advance.

[0034] FIG. 1 shows a battery abnormal condition prediction apparatus according to an embodiment, FIG. 2 is provided for description of an output signal of a first comparator according to a temperature voltage input according to the embodiment, FIG. 3 is provided for description of an output signal of a second comparator according to a pressure voltage input according to the embodiment, FIG. 4 is provided for description of an output signal of a third comparator according to a gas voltage input according to the embodiment, FIG. 5 is provided for description of an output signal of a first determining portion using the output signals of the first comparator and the second comparator as inputs according to the embodiment, and FIG. 6 is provided for description of an output signal of a second determining portion using the output signals of the first comparator and the third comparator as inputs according to the embodiment.

[0035] Referring to FIG. 1, a battery abnormal condition prediction apparatus 100 includes a receiving portion 10, a comparison portion 20, and a detection portion 30.

[0036] Each configuration shown in FIG. 1 is an example to describe the configuration of the battery abnormal condition prediction apparatus 100, and changes such as at least two components being combined, one component being separated into at least two components, or an additional component being added are possible, and the embodiment shown in FIG. 1 does not limit the present invention.

[0037] FIG. 7 is a flowchart provided for description of a battery abnormal condition prediction method according to an embodiment.

[0038] Hereinafter, referring to FIG. 1 to FIG. 7, an apparatus for predicting a battery abnormal condition, and a method thereof according to an embodiment, will be described.

[0039] First, the receiving portion 10 receives information indicating a temperature value, a pressure value, and a gas concentration value of a battery module measured by a temperature sensor 1, a pressure sensor 2, and a gas sensor 3, respectively (S10). For example, the receiving portion 10 may receive information indicating a temperature voltage V.sub.T, a pressure voltage V.sub.P, and a gas voltage V.sub.G, which respectively correspond to the temperature value, the pressure value, and the gas concentration value of the battery module.

[0040] Next, the comparison portion 20 compares the temperature value, the pressure value, and the gas concentration value of the battery module respectively with a first threshold value, a second threshold value, and a third threshold value, and may transmit a comparison result to the detection portion 320 (S20).

[0041] Specifically, the comparison portion 20 compares a temperature voltage V.sub.T, a pressure voltage V.sub.P, and a gas voltage V.sub.G, which respectively correspond to the temperature value, the pressure value, and the gas concentration value of the battery module with predetermined threshold values, and may output a comparison result as a digital signal. For example, the comparison portion 20 may include a voltage comparator that outputs a signal of a high level H when a voltage to be compared is greater than a predetermined threshold voltage, and outputs a signal of a low level L when the voltage to be compared is not larger than the threshold voltage.

[0042] Referring to FIG. 1, the comparison portion 20 may include a first comparator 21 that compares the temperature voltage V.sub.T with the first threshold voltage, a second comparator 22 that compares the pressure voltage V.sub.P with the second threshold voltage, and a third comparator 23 that compares the gas voltage V.sub.G with the third threshold voltage.

[0043] Referring to FIG. 2, (a) is a graph provided for description of a change over time of the temperature voltage V.sub.T corresponding to the temperature value of the battery module, and (b) is a graph displaying an output signal VC1 of the first comparator 21, which has the temperature voltage V.sub.T as an input. The first comparator 21 receives the temperature voltage V.sub.T in real time, compares the received temperature voltage V.sub.T with a first threshold voltage V.sub.aT, and outputs an output signal VC1 of a high level H or a low level L.

[0044] Since the temperature voltage V.sub.T is not greater than the first threshold voltage V.sub.aT until reaching T1, the output signal VC1 of the first comparator 21 is a low level L. At T1, the temperature voltage V.sub.T becomes higher than the first threshold voltage V.sub.aT, and therefore the output signal VC1 of the first comparator 21 is increased to the high level H.

[0045] Referring to FIG. 3, (a) is a graph provided for description of a change over time of the pressure voltage V.sub.P corresponding to the pressure value of the battery module, and (b) displays an output signal VC2 of the second comparator 22, which has the pressure voltage V.sub.P, as an input. The second comparator 22 receives the pressure voltage V.sub.P in real time, compares the received pressure voltage V.sub.P with a second threshold voltage V.sub.aP, and outputs a signal VC2 of a high level H or low level L.

[0046] Since the pressure voltage V.sub.P is not higher than the second threshold voltage V.sub.aP until reaching T2, the output signal VC2 of the second comparator 22 has a low level L. At T2, the pressure voltage V.sub.P becomes higher than the second threshold voltage V.sub.aP, and therefore the output signal VC2 of the second comparator 22 is increased to a high level H. At T3, the pressure voltage V.sub.P becomes lower than second threshold voltage V.sub.aP again, and thus output signal VC2 of the second comparator 22 is decreased to the low level L.

[0047] Referring to FIG. 4, (a) is a graph provided for description of a change over time of the gas voltage V.sub.G corresponding to the gas concentration value of the battery module, and (b) displays an output signal VC3 of the third comparator 23. The third comparator 23 receives the gas voltage V.sub.G in real time, compares the received gas voltage V.sub.G with a third threshold voltage V.sub.aG, and outputs a signal VC3 of a high level H or a low level L.

[0048] Since the gas voltage V.sub.G is not higher than the third threshold voltage V.sub.aG until reaching T4, the output signal VC3 of the third comparator 23 has a low level L. At T4, the gas voltage V.sub.G becomes higher than the third threshold voltage V.sub.aG, and therefore the output voltage VC3 of the third comparator 23 is increased to the high level H.

[0049] Next, the detection portion 30 receives a comparison result of the first threshold value, the second threshold value, and the third threshold value for each of the temperature value, the pressure value, and the gas concentration value of the battery module from the comparison portion 20, and determines whether an abnormal behavior of the battery occurs based on the comparison result (S30).

[0050] For example, the detection portion 30 determines that thermal runaway of the battery occurs when the pressure value exceeding the second threshold value falls below the second threshold value or the gas concentration value exceeds the third threshold value while the temperature value exceeds the first threshold value. In addition, the detection portion 30 may determine the occurrence of electrolyte solution leakage when the gas concentration value exceeds the third threshold value.

[0051] Referring to FIG. 1, the detection portion 30 includes a first determining portion 31, a second determining portion 32, a thermal runaway notifying portion 33, and an electrolyte solution leakage notifying portion 34, and determines abnormal behavior occurrence of the battery based on the signals VC1, VC2, and VC3 respectively from the first comparator 21, the second comparator 22, and the third comparator 23 and generates a corresponding notifying message.

[0052] Before thermal runaway occurs due to overcharge, over-discharge, or aging of the battery module, the temperature and gas concentration inside the battery module continuously rise until ignition, while the pressure increases rapidly and then decreases. That is, the pressure inside the battery module increases due to gas generation and then decreases when gas is discharged due to venting of the battery case. In the embodiment, a change in temperature and gas concentration inside the battery module may be monitored, or a change in temperature and pressure may be monitored, to detect whether battery thermal runaway occurs with high reliability.

[0053] Next, the first determining portion 31 and the second determining portion 32 respectively determine whether battery thermal runaway occurs based on the signals VC1, VC2, and VC3 output from the first comparator 21, the second comparator 22, and the third comparator 23 (S31).

[0054] The first determining portion 31 outputs a signal FF of the high level H when the output signal VC1 of the first comparator 21, used as a first input, is the high level H and the output signal VC2 of the second comparator 22, used as a second input, is changed to the low level L from the high level H.

[0055] For example, the first determining portion 31 includes a negative edge trigger flip-flop, and may output the signal FF of the high level H when a clock pulse receiving through the first input is “1 (high level)” and a clock pulse receiving through the second input is changed to “0 (low level)” from “1 (high level)”. That is, the first determining portion 31 detects the occurrence of thermal runaway by detecting a temperature change that continuously rises inside the battery module and the pressure change that increases and decreases rapidly.

[0056] Referring to FIG. 5, (a) shows the output signal VC1 of the first comparator 21, (b) shows the output signal VC2 of the second comparator 22, and (c) shows the output signal FF of the first determining portion 31, which has the output signals of the first comparator 21 and the second comparator 22 as inputs. At T3, the output signal VC1 of the first comparator 21 has the high level H and the output signal VC2 of the second comparator 22 is changed to the low level L from the high level H, the output signal FF of the first determining portion 31 has the high level H.

[0057] The second determining portion 32 outputs a signal AG of the high level H when the output signal V1 of the first comparator 21, which is used as the first input, and the output signal VC3 of the third comparator 23, which is used as the second input, both have the high level H.

[0058] For example, the second determining portion 32 includes an AND gate and thus may output the signal AG of “1 (high level)” when the first input and the second input both have “1 (high level)” and output the signal AG of “0 (low level)” in the remaining cases. That is, the second determining portion 32 detects the occurrence of thermal runaway by detecting a temperature change that continuously rises inside the battery module and the pressure change that increases and decreases rapidly.

[0059] Referring to FIG. 6, (a) shows the output signal VC1 of the first comparator 21, (b) shows the output signal VC3 of the third comparator 23, and (c) shows the output signal AG of the second determining portion 32 which uses the outputs of the first comparator 21 and the third comparator 23 as inputs. At T4, the output signal VC1 of the first comparator 21 and the output signal VC3 of the third comparator 23 both have the high level H, and the output signal AG of the second determining portion 32 has the high level H.

[0060] Next, the thermal runaway notifying portion 33 determines occurrence of thermal runaway of the battery when at least one of the output signals of the first determining portion 31 and the second determining portion 32 has the high level H (S31, Yes), and may generate a corresponding notification message (S33). In this case, when the output signal VC3 of the third comparator 23 corresponds to “1 (high level)”, the electrolyte solution leakage notifying portion 34 may determine occurrence of an electrolyte solution leakage due to thermal runaway and generate a corresponding notification message.

[0061] For example, the thermal runaway notifying portion 33 includes an OR gate, and thus may receive the output signal FF of the first determining portion 31 and the output signal AG of the second determining portion 32, and outputs a signal of “1 (high level)” when at least one of the received signals is “1 (high level)” and outputs a signal of “0 (low level)” when both of the received signals are “0 (low level)”.

[0062] Next, when no thermal runaway occurs in the battery (S31, No), the electrolyte solution leakage notifying portion 34 additionally determines whether an electrolyte solution leakage has occurred due to problems other than the thermal runaway (S35). The electrolyte solution leakage may also occur due to soft venting caused by a problem in battery case sealing.

[0063] When the output signal VC3 of the third comparator 23 corresponds to “1 (high level)”, the electrolyte solution leakage notifying portion 34 determines that the electrolyte solution leakage has occurred (S35, Yes) and may generate a corresponding notification message (S37).

[0064] FIG. 8 shows a battery system that includes a battery management system providing a battery abnormal condition prediction method according to an embodiment.

[0065] Referring to FIG. 8, a battery system 1000 includes a temperature sensor 1, a pressure sensor 2, a gas sensor 3, a battery module 4, and a battery management system (BMS) 5.

[0066] The temperature sensor 1 measures a temperature inside the battery module 4, and transmits information indicating the measured temperature to the BMS 5. The temperature sensor 1 may be implemented as a thermistor, and a value measured by the thermistor may be information that indicates the measured temperature. In FIG. 8, one temperature sensor 1 is attached to the battery module 4, but the present invention is not limited thereto, and the temperature sensor 1 may be representatively attached to a cell where heat is concentrated, or two or more temperature sensors 1 may be attached to two or more cells.

[0067] The temperature sensor 1 is implemented as a negative temperature coefficient (NTC) type of thermistor, and thus may measure a temperature inside the battery module 4 and convert the measured temperature to a temperature voltage V.sub.T. The temperature sensor 1 may transmit information that indicates the temperature voltage V.sub.T to the BMS 5.

[0068] The pressure sensor 2 measures a pressure inside the battery module 4, and transmits information that indicates the measured pressure to the BMS 5. The pressure sensor 2 is implemented as a pressure sensitive resistor (PSR) type, and thus may measure a pressure (force) applied to a case surface of the battery module 4 and convert the measured pressure to a corresponding pressure voltage V.sub.P. The pressure sensor 2 may transmit information that indicates the pressure voltage V.sub.P to the BMS 5. In FIG. 8, the pressure sensor 2 is attached between the outermost cell in the battery module 4 and a case of the battery module 4, but the present invention is not limited thereto, and two or more pressure sensors 2 may be attached between two or more cells.

[0069] The gas sensor 3 measures a gas concentration inside the battery module 4 and transmits information that indicates the measured gas concentration to the BMS 5. The gas sensor 3 measures a concentration of predetermined gas such as CO, CO.sub.2, and the like, and converts the measured gas concentration to a corresponding gas voltage V.sub.G. The gas sensor 3 may transmit information that indicates the gas voltage V.sub.G to the BMS 5.

[0070] The battery module 4 may supply requisite power to a plurality of battery cells that are connected in parallel/series. In FIG. 8, the battery module 4 includes a plurality of battery cells that are connected in series between two output terminals OUT1 (+) and OUT2 (−) of the battery system 1000, but the configurations and the connection relationship between the configurations shown in FIG. 8 are examples, and the present invention is not limited thereto.

[0071] The BMS 5 includes the battery abnormal condition prediction apparatus 100 according to the above-described embodiment of FIG. 1 to FIG. 7. The battery abnormal condition prediction apparatus 100 may predict occurrence of battery thermal runaway or an electrolyte solution leakage based on a temperature value, a pressure value, and a gas concentration of the battery module 4, respectively measured by the temperature sensor 1, the pressure sensor 2, and the gas sensor 3.

[0072] While this invention has been described in connection with what is presently considered to be practical embodiments, it is to be understood that the invention is not limited to the disclosed embodiments. On the contrary, it is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.