Apparatus and method for diagnosing battery

Abstract

An apparatus for diagnosing a battery according to one embodiment of the present disclosure comprises: a curve acquisition unit for acquiring a battery curve indicating a correspondence relationship between a voltage and a capacity of the battery; a curve adjustment unit that adjusts a preset reference cathode curve and a reference anode curve so as to correspond to the battery curve, thereby generating an adjusted cathode curve and an adjusted anode curve; and a control unit for extracting a diagnostic factor for the battery from the adjusted cathode curve and / or the adjusted anode curve, and diagnosing a state of the battery based on the extracted diagnostic factor.

Description

Technical Field

[0001] This application is based on and claims priority to Korean Patent Application No. 10-2024-0015252, filed with the Korean Intellectual Property Office on January 31, 2024, the disclosure of which is incorporated herein by reference in its entirety.

[0002] This disclosure relates to an apparatus and method for diagnosing a battery, and more specifically, to an apparatus and method for diagnosing the state of a battery. Background Technology

[0003] In recent years, demand for portable electronic products such as laptops, cameras, and mobile phones has grown dramatically, and electric vehicles, energy storage batteries, robots, and satellites have also seen significant development. Correspondingly, research is actively underway on high-performance batteries that allow for repeated charging and discharging.

[0004] Currently available batteries include nickel-cadmium batteries, nickel-metal hydride batteries, nickel-zinc batteries, and lithium batteries. Among them, lithium batteries have attracted much attention due to their almost non-existent memory effect compared to nickel-based batteries, as well as their very low self-discharge rate and high energy density.

[0005] While much research has been conducted on these batteries in terms of high capacity and high density, improving lifespan and safety is equally important. To improve battery safety, technologies for accurately diagnosing the current state of the battery are needed. Summary of the Invention

[0006] Technical issues

[0007] This disclosure is designed to address the problems of the prior art, and therefore aims to provide an apparatus and method for diagnosing the state of a battery in a non-destructive manner.

[0008] These and other objects and advantages of this disclosure may be understood from the following detailed description and will become more apparent from exemplary embodiments of this disclosure. Furthermore, it will be readily understood that the objects and advantages of this disclosure may be achieved by the means shown in the appended claims and combinations thereof.

[0009] Technical solution

[0010] An apparatus for diagnosing a battery according to one aspect of the present disclosure may include: a curve acquisition unit configured to acquire a battery curve representing the correspondence between the battery's voltage and capacity; a curve adjustment unit configured to adjust preset reference positive and negative electrode curves to correspond to the battery curves to generate adjusted positive and adjusted negative electrode curves; and a control unit configured to extract diagnostic factors for the battery from at least one of the adjusted positive and adjusted negative electrode curves, and diagnose the state of the battery based on the extracted diagnostic factors.

[0011] The control unit can be configured to calculate a degradation parameter, including at least one of available lithium loss rate, positive electrode loss rate, negative electrode loss rate and capacity loss rate, based on the extracted diagnostic factors, and to diagnose the state of the battery based on the calculated degradation parameter.

[0012] The control unit can be configured to determine a first characteristic value based on the adjustment of the positive electrode curve, and to calculate the available lithium loss rate based on the first characteristic value, a preset first reference characteristic value, and a preset reference difference.

[0013] The control unit can be configured to compare the available lithium loss rate with a preset first threshold and diagnose the battery state as a state of available lithium loss based on the comparison result.

[0014] The control unit can be configured to determine a second characteristic value based on the adjustment of the positive electrode curve, and to calculate the positive electrode loss rate based on the second characteristic value, a preset second reference characteristic value, and a preset reference difference.

[0015] The control unit can be configured to calculate the positive electrode change rate of the adjusted positive electrode curve, and calculate the positive electrode loss rate based on the positive electrode change rate and a preset reference positive electrode change rate.

[0016] The control unit can be configured to compare the positive electrode loss rate with a preset second threshold and diagnose the battery state as a positive electrode loss state based on the comparison result.

[0017] The control unit can be configured to calculate the negative electrode change rate of the adjusted negative electrode curve, and calculate the negative electrode loss rate based on the negative electrode change rate and a preset reference negative electrode change rate.

[0018] The control unit can be configured to compare the negative electrode loss rate with a preset third threshold and diagnose the battery state as a negative electrode loss state based on the comparison result.

[0019] The control unit can be configured to determine a first characteristic value and a second characteristic value based on the adjustment of the positive electrode curve, and to calculate the capacity loss rate based on the first characteristic value, the second characteristic value and a preset reference difference.

[0020] The control unit can be configured to determine a third characteristic value and a fourth characteristic value based on the adjustment of the negative electrode curve, and to calculate the capacity loss rate based on the third characteristic value, the fourth characteristic value and a preset reference difference.

[0021] The control unit can be configured to compare the capacity loss rate with a preset fourth threshold and diagnose the battery state as a capacity loss state based on the comparison result.

[0022] According to another aspect of this disclosure, a battery pack may include means for diagnosing the battery according to one aspect of this disclosure.

[0023] A vehicle according to another aspect of this disclosure may include a device for diagnosing a battery according to one aspect of this disclosure.

[0024] A method for diagnosing a battery according to another aspect of this disclosure may include a curve acquisition step, which acquires a battery curve representing the correspondence between the battery's voltage and capacity; a curve adjustment step, which adjusts preset reference positive and negative electrode curves to correspond to the battery curves to generate adjusted positive and adjusted negative electrode curves; a diagnostic factor extraction step, which extracts diagnostic factors for the battery from at least one of the adjusted positive and adjusted negative electrode curves; and a diagnosis step, which diagnoses the state of the battery based on the extracted diagnostic factors.

[0025] Beneficial effects

[0026] According to embodiments of this disclosure, an apparatus for diagnosing a battery can non-destructively estimate the positive and negative electrode curves of the battery, and specifically distinguish and diagnose the state of the battery based on the estimated positive and negative electrode curves.

[0027] In other words, the device used to diagnose batteries has the advantage of being able to generate positive / negative electrode curves that reflect the current state of the battery, and also being able to diagnose the state of the battery very specifically.

[0028] The effects of this disclosure are not limited to those mentioned above, and those skilled in the art will clearly understand from the description of the claims other effects not mentioned. Attached Figure Description

[0029] The accompanying drawings illustrate preferred embodiments of the present disclosure and, together with the foregoing disclosure, are provided to further understand the technical features of the present disclosure; therefore, the present disclosure is not to be construed as limited to the drawings.

[0030] Figure 1 This is a schematic diagram illustrating an apparatus for diagnosing a battery according to an embodiment of the present disclosure.

[0031] Figure 2 This is a diagram schematically illustrating the adjustment results of the reference positive electrode curve and the reference negative electrode curve according to embodiments of the present disclosure.

[0032] Figure 3 This is a schematic diagram illustrating the battery curve and a reference full-cell curve according to an embodiment of the present disclosure.

[0033] Figure 4 This is a diagram schematically illustrating degradation parameters according to an embodiment of the present disclosure.

[0034] Figure 5 This is a schematic diagram illustrating a battery pack according to another embodiment of the present disclosure.

[0035] Figure 6 This is a schematic diagram illustrating a vehicle according to another embodiment of the present disclosure.

[0036] Figure 7 This is a schematic diagram illustrating a method for diagnosing a battery according to yet another embodiment of the present disclosure. Detailed Implementation

[0037] It should be understood that the terms used in the specification and appended claims should not be construed as limited to their general or dictionary meanings, but rather interpreted based on their meanings and concepts corresponding to the technical aspects of this disclosure, in accordance with the principle that the inventors are permitted to define the terms appropriately for the best explanation.

[0038] Therefore, the descriptions presented herein are merely preferred examples for illustrative purposes and are not intended to limit the scope of this disclosure. It should be understood that other equivalents and modifications may be made thereto without departing from the scope of this disclosure.

[0039] Additionally, in describing this disclosure, detailed descriptions of known elements or functions are omitted herein if they would obscure the key subject matter of the disclosure.

[0040] Ordinal numbers, such as “first” and “second”, can be used to distinguish one element from another among various elements, but are not intended to limit these elements through these terms.

[0041] Throughout this specification, when a part is referred to as “comprising” or “including” any element, unless otherwise expressly stated, it means that the part may further include other elements, without excluding other elements.

[0042] Furthermore, throughout this specification, when a part is referred to as being “connected” to another part, it is not limited to the case where they are “directly connected” but also includes the case where they are “indirectly connected”, in which another element is inserted between them.

[0043] Preferred embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings.

[0044] Figure 1 This is a schematic diagram illustrating a device 100 for diagnosing batteries according to an embodiment of the present disclosure.

[0045] refer to Figure 1 The device 100 for diagnosing batteries may include a curve acquisition unit 110, a curve adjustment unit 120, and a control unit 130.

[0046] Here, a battery refers to a single, physically separable cell with negative and positive terminals. For example, a lithium-ion battery or a lithium polymer battery can be considered a battery. Additionally, the type of battery can be cylindrical, prismatic, or pouch-shaped. Furthermore, a battery can refer to a battery bank, battery module, or battery pack in which multiple cells are connected in series and / or in parallel. Hereafter, for ease of explanation, a battery is explained as referring to a single, independent cell.

[0047] The curve acquisition unit 110 can be configured to acquire a battery curve M, which represents the relationship between the battery's voltage and capacity.

[0048] For example, battery curve M represents the relationship between voltage V and capacity Q as the battery's state of charge (SOC) increases from a preset start-of-charge SOC or 0% to a preset end-of-charge SOC or 100%. As another example, battery curve M can represent the relationship between voltage V and capacity Q as the battery's state of charge increases from a preset start-of-discharge SOC or 100% to a preset end-of-discharge SOC or 0%.

[0049] For example, there are no particular restrictions on the charging or discharging rate (C) used to generate the battery profile M. However, it is preferable to charge or discharge the battery at a low rate to obtain a more accurate battery profile M. For example, the battery profile M can be generated during charging or discharging of the battery at 0.05C.

[0050] For example, the curve acquisition unit 110 can directly receive the battery curve M from the outside. That is, the curve acquisition unit 110 can obtain the battery curve M by connecting to the outside via a wired and / or wireless connection and receiving the battery curve M.

[0051] As another example, the curve acquisition unit 110 can receive battery information regarding the battery's voltage and capacity. Then, the curve acquisition unit 110 can generate a battery curve M based on the received battery information. In other words, the curve acquisition unit 110 can obtain the battery curve M by directly generating the battery curve M based on the battery information.

[0052] The curve acquisition unit 110 can be connected to communicate with the control unit 130. For example, the curve acquisition unit 110 can be connected to the control unit 130 via wired and / or wireless means. The curve acquisition unit can transmit the acquired battery curve M to the control unit 130.

[0053] The curve adjustment unit 120 can be configured to adjust preset reference positive curve Rp and reference negative curve Rn to correspond to the battery curve M, thereby generating an adjusted positive curve Rp' and an adjusted negative curve Rn'.

[0054] Here, the reference positive electrode curve Rp can be a curve representing the correspondence between the capacity and voltage of a preset reference positive electrode cell, corresponding to the positive electrode of the battery. For example, the reference positive electrode cell can be the positive electrode of a button cell or a three-electrode cell. As a specific example, the reference positive electrode curve Rp can be preset to correspond to the positive electrode of a battery in the early life (BOL) state. That is, the reference positive electrode curve Rp can be estimated as the positive electrode curve of a battery in the BOL state.

[0055] Additionally, the reference negative electrode curve Rn can be a curve representing the correspondence between the capacity and voltage of a preset reference negative electrode cell, corresponding to the negative electrode of the battery. For example, the reference negative electrode cell can be the negative electrode of a button cell or a three-electrode cell. As a specific example, the reference negative electrode curve Rn can be preset to correspond to the negative electrode of a battery in the BOL state. That is, the reference negative electrode curve Rn can be estimated as the negative electrode curve of a battery in the BOL state.

[0056] Specifically, the curve adjustment unit 120 can adjust the reference positive electrode curve Rp and the reference negative electrode curve Rn to correspond to the battery curve M. More specifically, the curve adjustment unit 120 can generate an adjusted positive electrode curve Rp' and an adjusted negative electrode curve Rn' by adjusting the reference positive electrode curve Rp and the reference negative electrode curve Rn. Furthermore, the curve adjustment unit 120 can generate a comparison curve based on the adjusted positive electrode curve Rp' and the adjusted negative electrode curve Rn'. The curve adjustment unit 120 can adjust the reference positive electrode curve Rp and the reference negative electrode curve Rn until the comparison curve corresponds to the battery curve M.

[0057] For example, the curve adjustment unit 120 can generate multiple comparison curves by shifting or capacity scaling the reference positive electrode curve Rp and the reference negative electrode curve Rn, and can specify the comparison curve with the smallest error to the battery curve M among the multiple comparison curves. Then, the curve adjustment unit 120 can determine the adjusted positive electrode curve Rp' corresponding to the specified comparison curve as the positive electrode curve of the battery. Then, the curve adjustment unit 120 can determine the adjusted negative electrode curve Rn' corresponding to the specified comparison curve as the negative electrode curve of the battery. That is, the adjusted positive electrode curve Rp' and the adjusted negative electrode curve Rn' corresponding to the specified comparison curve can be estimated as the positive electrode curve and the negative electrode curve of the battery, respectively.

[0058] Figure 2 This is a diagram schematically illustrating the adjustment results of the reference positive electrode curve Rp and the reference negative electrode curve Rn according to embodiments of the present disclosure.

[0059] Specifically, in Figure 2 In this embodiment, the curve adjustment unit 120 can generate the adjusted positive curve Rp' and the adjusted negative curve Rn' by adjusting the reference positive curve Rp and the reference negative curve Rn. That is, the adjusted positive curve Rp' and the adjusted negative curve Rn' are generated based on the intrinsic relationship between the reference positive curve Rp and the reference negative curve Rn.

[0060] Figure 3 This is a schematic diagram illustrating the battery curve M and the reference whole cell curve R according to an embodiment of the present disclosure.

[0061] exist Figure 3 In this embodiment, the reference full-cell curve R can be a curve based on the reference positive curve Rp and the reference negative curve Rn. Specifically, the voltage difference between the reference positive curve Rp and the reference negative curve Rn for the capacity can be expressed as the reference full-cell curve R.

[0062] Since the reference single-cell curve R is significantly different from the battery curve M, the curve adjustment unit 120 can generate multiple comparison curves corresponding to the battery curve M by adjusting the reference positive electrode curve Rp and the reference negative electrode curve Rn. The curve adjustment unit 120 can specify the comparison curve with the smallest error to the battery curve M from among the multiple comparison curves. Furthermore, the adjusted positive electrode curve Rp' and adjusted negative electrode curve Rn' based on the specified comparison curves can be set as the positive and negative electrode curves of the battery.

[0063] The control unit 130 can be configured to extract diagnostic factors for the battery from at least one of the positive electrode curve Rp' and the negative electrode curve Rn'.

[0064] Specifically, adjusting the positive electrode curve Rp' includes a first characteristic point corresponding to the positive electrode participation start point (hereinafter referred to as pi) and a second characteristic point corresponding to the positive electrode participation end point (hereinafter referred to as pf). Here, the positive electrode participation start point (pi) refers to the positive electrode point where the reaction begins during the charging process or where the reaction ends during the discharging process. The positive electrode participation end point (pf) refers to the positive electrode point where the reaction ends during the charging process or where the reaction begins during the discharging process.

[0065] Similarly, adjusting the negative electrode curve Rn' includes a third characteristic point (hereinafter referred to as ni) corresponding to the negative electrode participation start point and a fourth characteristic point (hereinafter referred to as nf) corresponding to the negative electrode participation end point. Here, the negative electrode participation start point (ni) refers to the negative electrode point where the reaction begins during the charging process or where the reaction ends during the discharging process. The negative electrode participation end point (nf) refers to the negative electrode point where the reaction ends during the charging process or where the reaction begins during the discharging process.

[0066] For example, in Figure 2 In this embodiment, adjusting the positive electrode curve Rp' may include a first characteristic point (pi') and a second characteristic point (pf'). Adjusting the negative electrode curve Rn' may include a third characteristic point (ni') and a fourth characteristic point (nf').

[0067] Adjust the first characteristic value (pi) of the positive electrode curve Rp' MOL ) is a value representing at least one of the capacitance, voltage, or state of charge (SOC) of the first characteristic point (pi'). Preferably, the first characteristic value (pi) MOL ) is the SOC of the first feature point (pi').

[0068] For example, the first eigenvalue (pi) MOL The first characteristic value (pi') can be calculated as the state of charge (SOC) of the capacity at the first characteristic point (pi') relative to the adjusted positive electrode curve Rp'. Assume the entire capacity range of the adjusted positive electrode curve Rp' is Qi[Ah] to Qf[Ah], and assume the capacity at the first characteristic point (pi') is Qpi[Ah]. MOL ) can be based on the formula " "Be calculated."

[0069] As another example, the first eigenvalue (pi) MOL It can also be calculated as the SOC of the capacity of the first characteristic point (pi') relative to the adjusted negative electrode curve Rn'.

[0070] As yet another example, the first eigenvalue (pi) MOL It can also be calculated as the SOC of the capacity of the first characteristic point (pi') relative to the battery curve M.

[0071] Adjust the second characteristic value (pf) of the positive electrode curve Rp' MOL ) is a value representing at least one of the capacitance, voltage, or state of charge (SOC) of the second characteristic point (pf'). Preferably, the second characteristic value (pf) MOL ) is the SOC of the second feature point (pf').

[0072] For example, the second eigenvalue (pf) MOL The second characteristic value (pf') can be calculated as the state of charge (SOC) of the capacity at the second characteristic point (pf') relative to the adjusted positive electrode curve Rp'. Assume the entire capacity range of the adjusted positive electrode curve Rp' is Qi[Ah] to Qf[Ah], and assume the capacity at the second characteristic point (pf') is Qpf[Ah]. MOL ) can be based on the formula " "Be calculated."

[0073] As another example, the second eigenvalue (pf) MOL It can also be calculated as the SOC of the capacity of the second characteristic point (pf') relative to the adjusted negative electrode curve Rn'.

[0074] As another example, the second eigenvalue (pf) MOL It can also be calculated as the SOC of the capacity at the second characteristic point (pf') relative to the battery curve M.

[0075] Adjust the third characteristic value (ni) of the negative electrode curve Rn' MOL ) is a value representing at least one of the capacitance, voltage, or SOC of the third characteristic point (ni'). Preferably, the third characteristic value (ni') MOL ) is the SOC of the third feature point (ni').

[0076] For example, the third eigenvalue (ni) MOL The third characteristic value (ni') can be calculated as the SOC at the third characteristic point (ni') relative to the capacity of the adjusted negative electrode curve Rn'. Assume the entire capacity range of the adjusted negative electrode curve Rn' is Qi[Ah] to Qf[Ah], and the capacity at the third characteristic point (ni') is Qni[Ah]. MOL ) can be based on the formula " "Be calculated."

[0077] As another example, the third eigenvalue (ni) MOL It can also be calculated as the SOC of the capacity of the third characteristic point (ni') relative to the adjusted negative electrode curve Rn'.

[0078] As yet another example, the third eigenvalue (ni) MOL It can also be calculated as the SOC of the capacity at the third characteristic point (ni') relative to the battery curve M.

[0079] Adjust the fourth characteristic value (nf) of the negative electrode curve Rn' MOL ) is a value representing at least one of the capacitance, voltage, or state of charge (SOC) of the fourth characteristic point (nf'). Preferably, the fourth characteristic value (nf') MOL ) is the SOC of the fourth feature point (nf').

[0080] For example, the fourth eigenvalue (nf) MOL The fourth eigenvalue (nf') can be calculated as the state of charge (SOC) of the capacity at the fourth eigenpoint (nf') relative to the adjusted negative electrode curve Rn'. Assume the entire capacity range of the adjusted negative electrode curve Rn' is Qi[Ah] to Qf[Ah], and the capacity at the fourth eigenpoint (nf') is Qnf[Ah]. MOL ) can be based on the formula " "Be calculated."

[0081] As another example, the fourth eigenvalue (nf) MOL It can also be calculated as the SOC of the capacity of the fourth characteristic point (nf') relative to the adjusted negative electrode curve Rn'.

[0082] As yet another example, the fourth eigenvalue (nf) MOL It can also be calculated as the SOC of the capacity at the fourth characteristic point (nf') relative to the battery curve M.

[0083] Adjusting the positive electrode change rate (ps) of the positive electrode curve Rp' MOL The value represents the rate of change of the adjusted positive electrode curve Rp' relative to the reference positive electrode curve Rp. In other words, the positive electrode change rate (ps) MOL ) is a scaling factor that adjusts the positive electrode curve Rp' relative to the reference positive electrode curve Rp. For example, the positive electrode change rate (ps) MOL The expression can be expressed as the ratio of the capacity difference between two points (pi', pf') on the positive electrode curve Rp' to the capacity difference between two points (pi0, pf0) on the reference positive electrode curve Rp. Here, pi0 corresponds to the positive electrode participation start point of the reference positive electrode curve Rp, and pf0 corresponds to the positive electrode participation end point of the reference positive electrode curve Rp.

[0084] Adjusting the negative electrode change rate (ns) of the negative electrode curve Rn' MOL The value (ns) represents the rate of change of the adjusted negative electrode curve Rn' relative to the reference negative electrode curve Rn. In other words, the negative electrode change rate (ns) MOL ) is a scaling factor that adjusts the negative electrode curve Rn' relative to the reference negative electrode curve Rn. For example, the negative electrode change rate (ns) MOLThe expression can represent the ratio of the capacity difference between two points (ni', nf') on the adjusted negative electrode curve Rn' to the capacity difference between two points (ni0, nf0) on the reference negative electrode curve Rn. Here, ni0 corresponds to the negative electrode participation start point of the reference negative electrode curve Rn, and nf0 corresponds to the negative electrode participation end point of the reference negative electrode curve Rn.

[0085] Specifically, the control unit 130 can extract the first feature value (pi). MOL ), second eigenvalue (pf) MOL ), third eigenvalue (ni) MOL ), fourth eigenvalue (nf) MOL ), positive electrode change rate (ps) MOL ) and negative electrode change rate (ns) MOL At least one of the following can be used as a diagnostic factor:

[0086] The control unit 130 can be configured to diagnose the state of the battery based on the extracted diagnostic factors.

[0087] Specifically, the control unit 130 can calculate degradation parameters for diagnosing the state of the battery based on diagnostic factors extracted from the positive electrode curve Rp' and / or the negative electrode curve Rn'.

[0088] For example, control unit 130 can be configured to output based on the extracted diagnostic factors, including the available lithium loss rate (Loss). Li ), positive electrode loss rate (Loss) P ), negative electrode loss rate (Loss) N ) and capacity loss rate (Loss) Q At least one of the degradation parameters in ).

[0089] Here, the lithium loss rate (Loss) is available. Li This refers to the percentage of usable lithium lost from a battery. In other words, the usable lithium loss rate (Loss) Li The available lithium loss refers to the extent to which lithium that can be used for charging and discharging is lost. Specifically, the available lithium loss rate (Loss) Li This can represent the amount of available lithium in a battery in its current state, based on how much of the available lithium was lost when the battery was in a BOL state. For example, if the available lithium loss rate (Loss) Li A 1% loss rate means that the available lithium capacity of a battery in its current state is 1% less than that of a battery in its BOL (Bottom of the Lithium) state. In other words, if the available lithium loss rate (Loss) is 1%, then the available lithium capacity of the battery in its current state is 1% less than that of a battery in its BOL state. Li If the lithium loss rate is 1%, then the state of available lithium health (SOH) of the battery in its current state is 99%. For example, the available lithium loss rate (Loss) Li It can be based on the first eigenvalue (pi)MOL ) is calculated.

[0090] Next, the positive electrode loss rate (Loss) P The positive electrode loss rate (or positive electrode loss rate) refers to the percentage of positive electrode loss in a battery. P This can represent how much the positive electrode capacity of a battery in its current state has been lost compared to its state of BOL (Best Before Least) positive electrode capacity. For example, if the positive electrode loss rate (Loss) P If the positive electrode capacity is 1%, it means that the positive electrode capacity of the battery in its current state is 1% lower than that of the battery in its BOL state. In other words, if the positive electrode loss rate (Loss) is 1%, then the positive electrode capacity of the battery in its current state is 1% lower than that of the battery in its BOL state. P If the positive electrode loss rate is 1%, then the state of shock (SOH) at the positive electrode of the battery in its current state is 99%. For example, the positive electrode loss rate (SOH) is... P It can be based on the second eigenvalue (pf) MOL ) or positive electrode change rate (pf) MOL ) is calculated.

[0091] Next, the negative electrode loss rate (Loss) N The negative electrode loss rate (or negative electrode loss rate) refers to the percentage of negative electrode losses in a battery. N The negative electrode capacity (or negative electrode loss rate) can represent how much the negative electrode capacity of a battery in its current state has been lost compared to that of a battery in its BOL state. For example, if the negative electrode loss rate (or negative electrode loss rate) is... N If the negative electrode loss rate is 1%, it means that the negative electrode capacity of the battery in its current state is 1% lower than that of the battery in its BOL state. In other words, if the negative electrode loss rate (Loss) is 1%, it means that the negative electrode capacity of the battery in its current state is 1% lower than that of the battery in its BOL state. N If the loss rate is 1%, then the negative electrode SOH of the battery in its current state is 99%. For example, the negative electrode loss rate (Loss) N It can be based on the negative electrode change rate (ns) MOL ) is calculated.

[0092] Finally, capacity loss rate (Loss) Q This represents the rate of capacity loss in a battery. In other words, the capacity loss rate (Loss) is... Q This can represent how much capacity a battery in its current state has lost compared to when it was in a BOL (Bottom of the Line) state. For example, if the capacity loss rate (Loss) is... Q A capacity loss rate of 1% means that the battery's capacity in its current state is 1% lower than that of a battery in its BOL (Bottom of the Line) state. In other words, if the capacity loss rate (Loss) is 1%, then the battery's capacity in its current state is 1% lower than that of a battery in its BOL state. Q If the capacity loss rate (Loss) is 1%, then the battery's current capacity (SOH) is 99%. For example, the capacity loss rate (Loss) QIt can be based on the first eigenvalue (pi) MOL ) and second eigenvalue (pf MOL The capacity loss rate (Loss) is calculated. As another example, the capacity loss rate (Loss) is... Q It can be based on the third eigenvalue (ni) MOL ) and the fourth eigenvalue (nf MOL ) is calculated.

[0093] Figure 4 This is a diagram schematically illustrating degradation parameters according to embodiments of the present disclosure. Specifically, Figure 4 This is a summary of data used for lithium loss rate (Loss) Li ), positive electrode loss rate (Loss) P ), negative electrode loss rate (Loss) N ) and capacity loss rate (Loss) Q The diagram shows the formula for ( ). The control unit 130 uses... Figure 4 A specific example of how the formula in the diagram calculates the degradation parameter will be described later.

[0094] Additionally, the control unit 130 can be configured to diagnose the battery's condition based on calculated degradation parameters.

[0095] Specifically, the control unit 130 can diagnose the state of the battery corresponding to the calculated degradation parameters. In other words, the battery state that can be calculated for each degradation parameter can be preset.

[0096] For example, the battery state that the control unit 130 can diagnose can be a state of available lithium loss, a state of positive electrode loss, a state of negative electrode loss, a state of capacity loss, or a normal state.

[0097] Specifically, the control unit 130 can be based on the available lithium loss rate (Loss Li This can be used to diagnose whether the battery is in a state of available lithium loss. Furthermore, the control unit 130 can base its diagnosis on the positive electrode loss rate (Loss). P This can be used to diagnose whether the battery is in a positive electrode loss state. Furthermore, the control unit 130 can base its diagnosis on the negative electrode loss rate (Loss...). N This can be used to diagnose whether the battery is in a negative electrode loss state. Furthermore, the control unit 130 can base its diagnosis on the capacity loss rate (Loss). Q The control unit 130 diagnoses whether the battery is in a state of capacity loss. Finally, if the battery is not in a state of available lithium loss, positive electrode loss, negative electrode loss, or capacity loss, the control unit 130 can diagnose the battery as being in a normal state.

[0098] Preferably, a threshold can be set for each degradation parameter. Here, the threshold is a preset value used to distinguish between normal and abnormal states. For example, values ​​less than or equal to the threshold can be considered to be in a normal state, and values ​​exceeding the threshold can be considered to be in an abnormal state. The control unit 130 can compare the degradation parameter with the corresponding threshold and diagnose the battery state based on the comparison result.

[0099] The battery diagnostic apparatus 100 according to embodiments of the present disclosure can non-destructively estimate the positive and negative electrode curves of the battery, and specifically distinguish and diagnose the battery state based on the estimated positive and negative electrode curves. That is, according to the battery diagnostic apparatus 100, positive / negative electrode curves reflecting the current state of the battery are generated, and the battery state can be diagnosed very specifically.

[0100] Meanwhile, the curve acquisition unit 110, curve adjustment unit 120, and control unit 130 included in the battery diagnostic device 100 may optionally include processors, application-specific integrated circuits (ASICs), other chipsets, logic circuits, registers, communication modems, data processing devices, etc., known in the art, to execute the various control logics performed in this disclosure. Furthermore, when the control logic is implemented as software, the curve acquisition unit 110, curve adjustment unit 120, and control unit 130 can be implemented as a collection of program modules. In this case, the program modules can be stored in memory and executed by the curve acquisition unit 110, curve adjustment unit 120, and control unit 130. The memory can be located internally or externally to the curve acquisition unit 110, curve adjustment unit 120, and control unit 130, and can be connected to the curve acquisition unit 110, curve adjustment unit 120, and control unit 130 by various well-known means.

[0101] Additionally, the device 100 for diagnosing the battery may further include a storage unit 140. The storage unit 140 may store data necessary for the operation and function of each component of the device 100 for diagnosing the battery, data generated during the execution of operations or functions, etc. The type of storage unit 140 is not particularly limited, as long as it is a known information storage means capable of recording, erasing, updating, and retrieving data. As examples, information storage means may include RAM, flash memory, ROM, EEPROM, registers, etc. Furthermore, the storage unit 140 may store program code that defines the processes that can be executed by the curve acquisition unit 110, the curve adjustment unit 120, and the control unit 130.

[0102] For example, storage unit 140 can store data for diagnosing the state of the battery, such as battery curve M, reference positive electrode curve Rp, reference negative electrode curve Rn, adjusted positive electrode curve Rp', adjusted negative electrode curve Rn', comparison curves, and degradation parameters.

[0103] Below, will describe Figure 4 Each parameter included in the embodiments.

[0104] (1) Loss Li This refers to the rate of loss of usable lithium.

[0105] (2) Loss P This refers to the positive electrode loss rate.

[0106] (3) Loss N This refers to the negative electrode loss rate.

[0107] (4) Loss Q This refers to the capacity loss rate.

[0108] (5) pi BOL This refers to the first reference characteristic value of the first reference characteristic point (pi0) of the reference positive electrode curve Rp. For example, pi BOL It can be the SOC of the first reference feature point (pi0). That is, the first reference feature value (pi0) BOL ) is the characteristic value of the positive electrode participation start point of the reference positive electrode curve Rp.

[0109] For example, the first reference eigenvalue (pi) BOL The first reference characteristic point (pi0) can be calculated as the state of charge (SOC) of the capacity relative to the reference cathode curve Rp. Assume the entire capacity range of the reference cathode curve Rp is Qi0[Ah] to Qf0[Ah], and the capacity of the first reference characteristic point (pi0) is Qpi0[Ah]. The first reference characteristic value (pi0) BOL ) can be based on the formula " "is calculated. As another example, the first reference eigenvalue (pi)" BOL The first reference eigenpoint (pi0) can be calculated as the state of charge (SOC) of the capacity at the first reference eigenpoint (pi0) relative to the reference negative electrode curve Rn. As another example, the first reference eigenpoint (pi0)... BOL ) can be calculated as the SOC of the capacity of the first reference feature point (pi0) relative to the reference full monomer curve R.

[0110] (6) pf BOL This refers to the second reference characteristic value of the second reference characteristic point (pf0) of the reference positive electrode curve Rp. For example, pf BOL It can be the SOC of the second reference feature point (pf0). That is, the second reference eigenvalue (pf0) BOL) is the characteristic value of the positive electrode participation termination point of the reference positive electrode curve Rp.

[0111] For example, the second reference eigenvalue (pf) BOL The second reference characteristic point (pf0) can be calculated as the state of charge (SOC) of the capacity relative to the reference cathode curve Rp. Assume the entire capacity range of the reference cathode curve Rp is Qi0[Ah] to Qf0[Ah], and the capacity of the second reference characteristic point (pf0) is Qpf0[Ah]. The second reference characteristic value (pf0) BOL ) can be based on the formula " "is calculated. As another example, the second reference eigenvalue (pf)" BOL The value of the second reference eigenpoint (pf0) can be calculated as the state of charge (SOC) of the capacity at the second reference eigenpoint relative to the reference negative electrode curve Rn. As another example, the second reference eigenpoint (pf0) can be calculated as the state of charge (SOC) of the capacity at the second reference eigenpoint relative to the reference negative electrode curve Rn. BOL ) can be calculated as the SOC of the capacity of the second reference feature point (pf0) relative to the reference full monomer curve R.

[0112] (7)ni BOL This refers to the third reference characteristic value of the third reference characteristic point (ni0) of the reference negative electrode curve Rn. For example, ni BOL It can be the SOC of the third reference feature point (ni0). That is, the third reference eigenvalue (ni0) BOL ) is the characteristic value of the negative electrode participation starting point of the reference negative electrode curve Rn.

[0113] For example, the third reference eigenvalue (ni) BOL The third reference characteristic point (ni0) can be calculated as the state of charge (SOC) of the capacity relative to the reference negative electrode curve Rn. Assume the entire capacity range of the reference negative electrode curve Rn is Qi0[Ah] to Qf0[Ah], and the capacity of the third reference characteristic point (ni0) is Qni0[Ah]. The third reference characteristic value (ni0) BOL ) can be based on the formula " "is calculated. As another example, the third reference eigenvalue (ni)" BOL The third reference eigenpoint (ni0) can also be calculated as the state of charge (SOC) of the capacity at the third reference eigenpoint (ni0) relative to the reference negative electrode curve Rn. As yet another example, the third reference eigenpoint (ni0)... BOL It can also be calculated as the SOC of the capacity of the third reference feature point (ni0) relative to the reference full monomer curve R.

[0114] (8) nf BOL This refers to the fourth reference characteristic value of the fourth reference characteristic point (nf0) of the reference negative electrode curve Rn. For example, nf BOL It can be the SOC of the fourth reference feature point (nf0). That is, the fourth reference eigenvalue (nf0)BOL ) is the characteristic value of the negative electrode participation termination point of the reference negative electrode curve Rn.

[0115] For example, the fourth reference eigenvalue (nf) BOL The fourth reference eigenvalue (nf0) can be calculated as the state of charge (SOC) of the capacity at the fourth reference eigenvalue (nf0) relative to the reference negative electrode curve Rn. Assume the entire capacity range of the reference negative electrode curve Rn is Qi0[Ah] to Qf0[Ah], and the capacity at the fourth reference eigenvalue (nf0) is Qnf0[Ah]. BOL ) can be based on the formula " "is calculated. As another example, the fourth reference eigenvalue (nf)" BOL The fourth reference eigenpoint (nf0) can also be calculated as the state of charge (SOC) of the capacity at the fourth reference eigenpoint (nf0) relative to the reference negative electrode curve Rn. As another example, the fourth reference eigenpoint (nf0)... BOL It can also be calculated as the SOC of the capacity of the fourth reference feature point (nf0) relative to the reference full monomer curve R.

[0116] (9) ps BOL This refers to the reference positive electrode change rate of the reference positive electrode curve Rp. Specifically, ps BOL This refers to the rate of change of the reference positive electrode curve Rp relative to the initial positive electrode curve. Here, if the initial positive electrode curve and the reference positive electrode curve Rp are the same, then ps BOL It can be 1 or 100%. In the following text, for ease of explanation, the initial positive electrode curve is defined to be the same as the reference positive electrode curve Rp.

[0117] (10) ns BOL This refers to the rate of change of the reference negative electrode in the reference negative electrode curve Rn. Specifically, ns BOL This refers to the rate of change of the reference negative electrode curve Rn relative to the initial negative electrode curve. Here, if the initial negative electrode curve and the reference negative electrode curve Rn are the same, then ns BOL It can be 1 or 100%. In the following text, for ease of explanation, the initial negative electrode curve is defined to be the same as the reference negative electrode curve Rn.

[0118] (11)pi MOL This refers to adjusting the first characteristic value of the first characteristic point (pi') of the positive electrode curve Rp'. For example, pi MOL It can be the SOC of the first feature point (pi').

[0119] (12) pf MOL This refers to adjusting the second characteristic value of the second characteristic point (pf') of the positive electrode curve Rp'. For example, pf MOL It can be the SOC of the second feature point (pf').

[0120] (13)niMOL This refers to adjusting the third characteristic value of the third characteristic point (ni') of the negative electrode curve Rn'. For example, ni MOL It can be the SOC of the third feature point (ni').

[0121] (14) nf MOL This refers to adjusting the fourth characteristic value of the fourth characteristic point (nf') of the negative electrode curve Rn'. For example, nf MOL It can be the SOC of the fourth feature point (nf').

[0122] (15) ps MOL This refers to adjusting the positive electrode change rate of the positive electrode curve Rp'. Specifically, ps MOL This refers to adjusting the rate of change of the positive electrode curve Rp' relative to the reference positive electrode curve Rp.

[0123] (16) ns MOL This refers to adjusting the rate of change of the negative electrode in the negative electrode curve Rn'. Specifically, ns MOL This refers to adjusting the rate of change of the negative electrode curve Rn' relative to the reference negative electrode curve Rn.

[0124] (17) Diff ref This refers to a preset reference difference. Specifically, the reference difference can be set to a first reference feature value (pi). BOL ) and the second reference eigenvalue (pf) BOL The difference between ) or the third reference eigenvalue (ni) BOL ) and the fourth reference eigenvalue (nf BOL The difference between the first reference eigenvalues ​​(pi). BOL ) and the second reference eigenvalue (pf) BOL The difference between ) and the third reference eigenvalue (ni) BOL ) and the fourth reference eigenvalue (nf BOL The difference between them is the same. In the following text, for ease of explanation, the reference difference will be referred to as Diff. ref .

[0125] (18) Preferably, if the first characteristic value (pi) MOL The value is calculated for the capacity of the adjusted positive electrode curve Rp', then the first reference characteristic value (pi) is... BOL It can also be a value calculated for the capacity of a reference positive electrode curve Rp. If the first characteristic value (pi) MOL The value is calculated for the capacity of the adjusted negative electrode curve Rn', then the first reference characteristic value (pi) BOL It can also be a value calculated for the capacity of the reference negative electrode curve Rn. If the first characteristic value (pi) MOLThe value is the capacity calculated for battery curve M. The first reference characteristic value (pi) is... BOL It can also be a value calculated for the capacity of a reference full monomer curve R.

[0126] Below is an example in which the control unit 130 diagnoses the state of the battery as a state of available lithium loss.

[0127] Control unit 130 can be configured to determine a first characteristic value (pi) based on the adjustment of the positive electrode curve Rp'. MOL ).

[0128] For example, in Figure 2 In one embodiment, the control unit 130 can determine the first characteristic point (pi') based on the adjustment of the positive electrode curve Rp'. Furthermore, the control unit 130 can determine the first characteristic value (pi) based on the SOC of the first characteristic point (pi'). MOL ).

[0129] The control unit 130 can be configured to be based on a first feature value (pi) MOL ), the preset first reference feature value (pi) BOL The available lithium loss rate (Loss) is calculated using the difference between the available lithium loss rate and a preset reference value. Li ).

[0130] Here, the first reference eigenvalue (pi) BOL ) and reference difference (Diff) ref (It is as described above.)

[0131] Specifically, the control unit 130 can be based on a first feature value (pi). MOL ), first reference eigenvalue (pi) BOL ) and reference difference (Diff) ref To calculate the available lithium loss rate (Loss) Li ).

[0132] For example, in Figure 4 In one embodiment, the control unit 130 can transfer the first feature value (pi) MOL ) and the first reference eigenvalue (pi) BOL The difference between the two values ​​divided by the reference difference (Diff) ref To calculate the available lithium loss rate (Loss) Li ).

[0133] Control unit 130 can be configured to control the available lithium loss rate (Loss) Li It is compared with a preset first threshold.

[0134] Here, the first threshold is used to determine the available lithium loss rate (Loss) LiThis refers to a preset reference value indicating whether the condition is within a normal range. For example, the first threshold can be preset experimentally and / or theoretically. Preferably, the first threshold can be preset by taking into account the battery type and condition (degree of degradation, etc.).

[0135] Specifically, the control unit 130 can measure the available lithium loss rate (Loss) Li The value is directly compared with a first threshold. For example, the control unit 130 can compare the available lithium loss rate (Loss) with the first threshold. Li The size of ) is compared with the first threshold.

[0136] The control unit 130 can be configured to diagnose the state of the battery as a state of available lithium loss based on the comparison results.

[0137] For example, if the available lithium loss rate (Loss) Li If the degree of loss of available lithium exceeds the first threshold, the control unit 130 can diagnose the battery state as a state of available lithium loss.

[0138] When available lithium is lost, the lost lithium can be deposited as a metal on the surface of the battery's negative electrode. This phenomenon of lithium deposition as a metal is called lithium plating. Because this phenomenon leads to internal short circuits in the battery, it is a major cause of battery fires and / or explosions. Therefore, the device 100 for diagnosing the battery can non-destructively diagnose the battery's condition based on extracted diagnostic factors, thereby preventing accidents in advance.

[0139] Below is an example in which the control unit 130 diagnoses the state of the battery as a positive electrode loss state.

[0140] In one embodiment, the control unit 130 can be configured to determine a second characteristic value (pf) based on the adjustment of the positive electrode curve Rp'. MOL ).

[0141] For example, in Figure 2 In one embodiment, the control unit 130 can determine a second characteristic point (pf') corresponding to the end point of positive electrode participation in the adjustment positive electrode curve Rp'. Then, the control unit 130 can determine a second characteristic value (pf) based on the capacity of the second characteristic point (pf'). MOL ).

[0142] Control unit 130 can be configured to be based on a second characteristic value (pf) MOL ), and the preset second reference eigenvalue (pf) BOL The positive electrode loss rate is calculated using the difference between the positive electrode and a preset reference value. P ).

[0143] Here, the second reference eigenvalue (pf) BOL ) and reference difference (Diff) ref (It is as described above.)

[0144] Specifically, the control unit 130 can be based on the second characteristic value (pf) MOL ), second reference eigenvalue (pf) BOL ) and reference difference (Diff) ref To calculate the positive electrode loss rate (Loss) P ).

[0145] For example, in Figure 4 In one embodiment, the control unit 130 can transfer the second feature value (pf) MOL ) and the second reference eigenvalue (pf) BOL The difference between the two values ​​divided by the reference difference (Diff) ref To calculate the positive electrode loss rate (Loss) P ).

[0146] Control unit 130 can be configured to control the positive electrode loss rate (Loss P It is compared with a preset second threshold.

[0147] Here, the second threshold can be used to determine the positive electrode loss rate (Loss). P This refers to a preset reference value indicating whether the condition is within a normal range. For example, the second threshold can be preset experimentally and / or theoretically. Preferably, the second threshold can be preset by taking into account the battery type and condition (degree of degradation, etc.).

[0148] Specifically, the control unit 130 can control the positive electrode loss rate (Loss P The first threshold is directly compared to the second threshold. For example, the control unit 130 can directly compare the positive electrode loss rate (Loss) with the second threshold. P The size of the threshold is compared with the second threshold.

[0149] The control unit 130 can be configured to diagnose the state of the battery as a positive electrode loss state based on the comparison results.

[0150] For example, if the positive electrode loss rate (Loss P If the degree of positive electrode loss exceeds the second threshold, the control unit 130 can diagnose the battery state as a positive electrode loss state.

[0151] In another embodiment, the control unit 130 can be configured to calculate the positive electrode change rate (ps) of the adjusted positive electrode curve Rp'. MOLFurthermore, the control unit 130 can be configured to base its operation on the positive electrode change rate (ps). MOL ) and preset reference positive electrode change rate (ps) BOL To calculate the positive electrode loss rate (Loss) P ).

[0152] Here, we refer to the positive electrode change rate (ps) BOL ) and positive electrode change rate (ps) MOL (It is as described above.)

[0153] Specifically, the control unit 130 can be based on the reference positive electrode change rate (ps). BOL ) and positive electrode change rate (ps) MOL To calculate the positive electrode loss rate (Loss) P ).

[0154] For example, in Figure 4 In one embodiment, the control unit 130 can control the reference positive electrode change rate (ps) BOL ) and positive electrode change rate (ps) MOL The difference between the two is divided by the reference positive electrode change rate (ps). BOL To calculate the positive electrode loss rate (Loss) P ).

[0155] In other words, the device 100 for diagnosing batteries can calculate the positive electrode loss rate (Loss) in multiple ways. P This is used to diagnose whether the battery is in a state of positive electrode loss.

[0156] Below is an example in which the control unit 130 diagnoses the state of the battery as a negative electrode loss state.

[0157] Control unit 130 can be configured to calculate the rate of change of the negative electrode (ns) of the adjusted negative electrode curve Rn'. MOL Additionally, the control unit 130 can be configured to base its operation on the negative electrode change rate (ns). MOL ) and the preset reference negative electrode change rate (ns) BOL To calculate the negative electrode loss rate (Loss) N ).

[0158] Here, the negative electrode change rate (ns) is referenced. BOL ) and negative electrode change rate (ns) MOL (It is as described above.)

[0159] Specifically, the control unit 130 can be based on the reference negative electrode change rate (ns). BOL ) and negative electrode change rate (ns) MOL To calculate the negative electrode loss rate (Loss) N ).

[0160] For example, in Figure 4 In one embodiment, the control unit 130 can control the reference negative electrode change rate (ns) BOL ) and negative electrode change rate (ns) MOL The difference between the two is divided by the reference negative electrode change rate (ns). BOL To calculate the negative electrode loss rate (Loss) N ).

[0161] Control unit 130 can be configured to control the negative electrode loss rate (Loss) N It is compared with a preset third threshold.

[0162] Here, the third threshold can determine the negative electrode loss rate (Loss). N This refers to a preset reference value indicating whether the condition is within a normal range. For example, the third threshold can be preset experimentally and / or theoretically. Preferably, the third threshold can be preset by taking into account the battery type and condition (degree of degradation, etc.).

[0163] Specifically, the control unit 130 can control the negative electrode loss rate (Loss N The loss rate can be directly compared with the third threshold. For example, the control unit 130 can compare the loss rate with the negative electrode loss rate. N The size of the threshold is compared with the third threshold.

[0164] The control unit 130 can be configured to diagnose the state of the battery as a negative electrode loss state based on the comparison results.

[0165] For example, if the negative electrode loss rate (Loss N If the degree of negative electrode loss exceeds the third threshold, the control unit 130 can diagnose the battery state as a negative electrode loss state.

[0166] Below is an example in which the control unit 130 diagnoses the state of the battery as a state of capacity loss.

[0167] In one embodiment, the control unit 130 can be configured to determine a first characteristic value (pi) based on the adjustment of the positive electrode curve Rp'. MOL ) and second eigenvalue (pf MOL Additionally, the control unit 130 can be configured to base its operation on a first feature value (pi). MOL ), second eigenvalue (pf) MOL The capacity loss rate is calculated using the difference between the target value and a preset reference value. Q ).

[0168] Here, the first eigenvalue (pi) MOL), second eigenvalue (pf) MOL ) and reference difference (Diff) ref (It is as described above.)

[0169] Specifically, the control unit 130 can be based on a first feature value (pi). MOL ), second eigenvalue (pf) MOL ) and reference difference (Diff) ref To calculate the capacity loss rate (Loss) Q ).

[0170] For example, in Figure 4 In one embodiment, the control unit 130 can calculate a first feature value (pi) MOL ) and the second eigenvalue (pf MOL The positive difference (pf) is calculated from the difference between the two. MOL -pi MOL Then, the control unit 130 can use the reference difference (Diff) to... ref ) and positive difference (pf) MOL -pi MOL The difference between the two values ​​divided by the reference difference (Diff) ref To calculate the capacity loss rate (Loss) Q ).

[0171] Control unit 130 can be configured to control the capacity loss rate (Loss) Q It is compared with the preset fourth threshold.

[0172] Here, the fourth threshold is used to determine the capacity loss rate (Loss). Q This refers to a preset reference value indicating whether the condition is within a normal range. For example, the fourth threshold can be preset experimentally and / or theoretically. Preferably, the fourth threshold can be preset by taking into account the battery type and condition (degree of degradation, etc.).

[0173] Specifically, the control unit 130 can measure the capacity loss rate (Loss Q The capacity loss rate can be directly compared with the fourth threshold. For example, the control unit 130 can compare the capacity loss rate with the fourth threshold. Q The size of ) is compared with the fourth threshold.

[0174] The control unit 130 can be configured to diagnose the state of the battery as a state of capacity loss based on the comparison results.

[0175] For example, if the capacity loss rate (Loss) QIf the degree of positive electrode loss exceeds the fourth threshold, the control unit 130 can diagnose the battery state as a positive electrode loss state.

[0176] In another embodiment, the control unit 130 may be configured to determine a third characteristic value (ni) based on the adjustment of the negative electrode curve Rn'. MOL ) and the fourth eigenvalue (nf MOL Furthermore, the control unit 130 can be configured based on a third characteristic value (ni). MOL ), fourth eigenvalue (nf) MOL The capacity loss rate is calculated using the difference between the target value and a preset reference value. Q ).

[0177] Here, the third eigenvalue (ni) MOL ), fourth eigenvalue (nf) MOL ) and reference difference (Diff) ref (It is as described above.)

[0178] Specifically, the control unit 130 can be based on a third feature value (ni). MOL ), fourth eigenvalue (nf) MOL ) and reference difference (Diff) ref To calculate the capacity loss rate (Loss) Q ).

[0179] For example, in Figure 4 In one embodiment, the control unit 130 can calculate a third feature value (ni) MOL ) and the fourth eigenvalue (nf MOL The negative range (nf) is calculated by the difference between the two. MOL -ni MOL Then, the control unit 130 can use the reference difference (Diff) to... ref ) and negative extreme difference (nf) MOL -ni MOL The difference between the two values ​​divided by the reference difference (Diff) ref To calculate the capacity loss rate (Loss) Q ).

[0180] In other words, the device 100 for diagnosing batteries can calculate the capacity loss rate (Loss) in various ways. Q This can be used to diagnose whether a battery is in a state of capacity loss.

[0181] Below is an example in which the control unit 130 diagnoses the battery's state as normal.

[0182] Specifically, if the battery is not in a state of available lithium loss, positive electrode loss, negative electrode loss, or capacity loss, the control unit 130 can diagnose the battery as being in a normal state.

[0183] In other words, if the available lithium loss rate (Loss Li ) equal to or less than the first threshold, positive electrode loss rate (Loss) P ) equal to or less than the second threshold, negative pole loss rate (Loss) N ) equal to or less than the third threshold, and the capacity loss rate (Loss) Q If the value is equal to or less than the fourth threshold, the control unit 130 can diagnose the battery state as normal.

[0184] The battery diagnostic apparatus 100 according to embodiments of the present disclosure can conservatively set the battery state to be diagnosed as normal. That is, the battery state can only be diagnosed as normal when all diagnostic results using the four degradation parameters are positive. Therefore, the battery diagnostic apparatus 100 can rigorously detect batteries exhibiting abnormal behavior, thereby preventing accidents caused by abnormal behavior in advance.

[0185] Additionally, the control unit 130 can be configured to change the preset usage conditions of the battery based on diagnostic results.

[0186] For example, the control unit 130 may appropriately change at least one of the maximum permissible temperature, maximum C rate, upper limit voltage (or upper limit SOC), and lower limit voltage (or lower limit SOC) to correspond to the state of the battery.

[0187] In other words, according to one embodiment of this disclosure, the battery diagnostic apparatus 100 can prevent further degradation of the battery's condition by changing the battery's usage conditions based on a rigorously diagnosed battery state. Additionally, the battery diagnostic apparatus 100 can increase the battery's expected lifespan by appropriately changing the usage conditions to correspond to the battery's state.

[0188] The battery diagnostic apparatus 100 according to this disclosure can be applied to a battery management system (BMS). That is, the BMS according to this disclosure may include the battery diagnostic apparatus 100 described above. In this configuration, at least some of the components of the battery diagnostic apparatus 100 can be implemented by supplementing or adding the functionality of components included in a conventional BMS. For example, the curve acquisition unit 110, curve adjustment unit 120, control unit 130, and storage unit 140 of the battery diagnostic apparatus 100 can be implemented as components of the BMS.

[0189] Additionally, the device 100 for diagnosing batteries according to this disclosure may be provided in a battery pack. That is, a battery pack according to this disclosure may include the device 100 for diagnosing batteries and at least one battery cell as described above. Additionally, the battery pack may further include electrical components (relays, fuses, etc.) and a housing.

[0190] Figure 5 This is a schematic diagram illustrating a battery pack 10 according to another embodiment of the present disclosure.

[0191] The positive terminal of battery 11 can be connected to the positive terminal P+ of battery pack 10, and the negative terminal of battery 11 can be connected to the negative terminal P- of battery pack 10.

[0192] The measuring unit 12 can be connected to a first sensing line SL1, a second sensing line SL2, and a third sensing line SL3. Specifically, the measuring unit 12 can be connected to the positive terminal of the battery 11 via the first sensing line SL1 and to the negative terminal of the battery 11 via the second sensing line SL2. The measuring unit 12 can measure the voltage of the battery 11 based on the voltage measured at each of the first sensing line SL1 and the second sensing line SL2.

[0193] Furthermore, the measurement unit 12 can be connected to the current measurement unit A via the third sensing line SL3. For example, the current measurement unit A can be an ammeter or a shunt resistor capable of measuring the charging current and discharging current of the battery 11. The measurement unit 12 can measure the charging current of the battery 11 via the third sensing line SL3 to calculate the amount of charge. Additionally, the measurement unit 12 can measure the discharging current of the battery 11 via the third sensing line SL3 to calculate the amount of discharge.

[0194] For example, the curve acquisition unit 110 can receive battery information about the battery's voltage and current from the measurement unit 12. Then, the curve acquisition unit 110 can generate a battery curve M based on the battery information.

[0195] As another example, curve acquisition unit 110 can receive battery curve M from measurement unit 12.

[0196] An external device can be connected to the positive terminal P+ and the negative terminal P- of the battery pack 10. For example, the external device can be a charging device or a load. In addition, the positive terminal of the battery 11, the positive terminal P+ of the battery pack 10, the external device, the negative terminal P- of the battery pack 10, and the negative terminal of the battery 11 can be electrically connected.

[0197] Figure 6 The figure schematically illustrates a vehicle 600 according to yet another embodiment of the present disclosure.

[0198] refer to Figure 6 The battery pack 610 according to embodiments of this disclosure can be included in a vehicle 600, such as an electric vehicle (EV) or a hybrid vehicle (HV). Additionally, the battery pack 610 can supply power to a motor via an inverter provided in the vehicle 600 to drive the vehicle 600. Here, the battery pack 610 may include a device 100 for diagnosing the battery. That is, the vehicle 600 may include a device 100 for diagnosing the battery. In this case, the device 100 for diagnosing the battery may be an on-board device included in the vehicle 600.

[0199] Figure 7 This is a schematic diagram illustrating a method for diagnosing a battery according to yet another embodiment of the present disclosure.

[0200] refer to Figure 7 The method for diagnosing a battery may include: a curve acquisition step (S100), a curve adjustment step (S200), a diagnostic factor extraction step (S300), and a diagnostic step (S400).

[0201] Preferably, each step of the method for diagnosing the battery can be performed by the device 100 for diagnosing the battery. Hereinafter, for ease of explanation, content overlapping with the above description will be omitted or briefly described.

[0202] The curve acquisition step (S100) is a step of obtaining a battery curve M that represents the correspondence between the battery's voltage and capacity, and can be executed by the curve acquisition unit 110.

[0203] For example, the curve acquisition unit 110 can directly receive the battery curve M from the outside. That is, the curve acquisition unit 110 can obtain the battery curve M by connecting to the outside via a wired and / or wireless connection and receiving the battery curve M.

[0204] As another example, the curve acquisition unit 110 can receive battery information regarding the battery's voltage and capacity. Then, the curve acquisition unit 110 can generate a battery curve M based on the received battery information. In other words, the curve acquisition unit 110 can obtain the battery curve M by directly generating the battery curve M based on the battery information.

[0205] The curve adjustment step (S200) is a step of adjusting the preset reference positive electrode curve Rp and reference negative electrode curve Rn to correspond to the battery curve M to generate the adjusted positive electrode curve Rp' and the adjusted negative electrode curve Rn', and can be executed by the curve adjustment unit 120.

[0206] For example, the curve adjustment unit 120 can generate multiple comparison curves by shifting or capacity scaling the reference positive electrode curve Rp and the reference negative electrode curve Rn, and specify the comparison curve with the smallest error relative to the battery curve M among the multiple comparison curves. Then, the curve adjustment unit 120 can determine the adjusted positive electrode curve Rp' corresponding to the specified comparison curve as the positive electrode curve of the battery. Then, the curve adjustment unit 120 can determine the adjusted negative electrode curve Rn' corresponding to the specified comparison curve as the negative electrode curve of the battery.

[0207] The diagnostic factor extraction step (S300) is a step of extracting diagnostic factors of the battery from at least one of the positive electrode curve Rp' and the negative electrode curve Rn', and can be executed by the control unit 130.

[0208] For example, the control unit 130 can extract the first feature value (pi). MOL ), second eigenvalue (pf) MOL ), third eigenvalue (ni) MOL ), fourth eigenvalue (nf) MOL ), positive electrode change rate (ps) MOL ) and negative electrode change rate (ns) MOL At least one of the following can be used as a diagnostic factor:

[0209] The diagnostic step (S400) is a step of diagnosing the state of the battery based on the extracted diagnostic factors, and can be executed by the control unit 130.

[0210] For example, control unit 130 can be configured to calculate, based on the extracted diagnostic factors, including the available lithium loss rate (Loss). Li ), positive electrode loss rate (Loss) P ), negative electrode loss rate (Loss) N ) and capacity loss rate (Loss) Q At least one of the degradation parameters in ).

[0211] Additionally, the control unit 130 can be configured to diagnose the battery's state based on the generated degradation parameters. For example, the control unit 130 can diagnose the battery's state as at least one of a usable lithium loss state, a positive electrode loss state, a negative electrode loss state, a capacity loss state, and a normal state.

[0212] The embodiments of this disclosure described above can be implemented not only by apparatus and methods, but also by a program with functions corresponding to the configuration of the embodiments of this disclosure, or by a recording medium on which the program is recorded. Those skilled in the art can readily implement the program or recording medium based on the above description of the embodiments.

[0213] This disclosure has been described in detail. However, it should be understood that while the detailed description and specific examples indicate preferred embodiments of this disclosure, they are given by way of illustration only, as various changes and modifications within the scope of this disclosure will become apparent to those skilled in the art based on this detailed description.

[0214] Additionally, those skilled in the art can make many substitutions, modifications and variations to the present disclosure described above without departing from the technical aspects of the present disclosure; and the present disclosure is not limited to the embodiments and drawings described above, and various embodiments can be selectively combined in part or in whole to allow for various modifications.

[0215] (Explanation of the labels in the attached diagram)

[0216] 10: Battery Pack

[0217] 11: Battery

[0218] 12: Measurement Unit

[0219] 100: Devices for diagnosing batteries

[0220] 110: Curve Acquisition Unit

[0221] 120: Curve Adjustment Unit

[0222] 130: Control Unit

[0223] 140: Storage unit

[0224] 600: Vehicles

[0225] 610: Battery Pack

Claims

1. A device for diagnosing a battery, comprising: A curve acquisition unit is configured to acquire a battery curve representing the relationship between the battery's voltage and capacity. A curve adjustment unit is configured to adjust preset reference positive and negative curves to correspond to the battery curve, thereby generating an adjusted positive and negative curve. as well as A control unit configured to extract diagnostic factors for the battery from at least one of the adjusted positive electrode curve and the adjusted negative electrode curve, and to diagnose the state of the battery based on the extracted diagnostic factors.

2. The device for diagnosing batteries according to claim 1, in, The control unit is configured to calculate a degradation parameter, including at least one of available lithium loss rate, positive electrode loss rate, negative electrode loss rate and capacity loss rate, based on the extracted diagnostic factors, and to diagnose the state of the battery based on the calculated degradation parameter.

3. The device for diagnosing batteries according to claim 2, in, The control unit is configured to determine a first characteristic value based on the adjusted positive electrode curve, and to calculate the available lithium loss rate based on the first characteristic value, a preset first reference characteristic value, and a preset reference difference.

4. The device for diagnosing batteries according to claim 2, in, The control unit is configured to compare the available lithium loss rate with a preset first threshold, and diagnose the state of the battery as a state of available lithium loss based on the comparison result.

5. The device for diagnosing batteries according to claim 2, in, The control unit is configured to determine a second characteristic value based on the adjusted positive electrode curve, and to calculate the positive electrode loss rate based on the second characteristic value, a preset second reference characteristic value, and a preset reference difference.

6. The apparatus for diagnosing batteries according to claim 2, in, The control unit is configured to calculate the positive electrode change rate of the adjusted positive electrode curve, and to calculate the positive electrode loss rate based on the positive electrode change rate and a preset reference positive electrode change rate.

7. The apparatus for diagnosing batteries according to claim 2, in, The control unit is configured to compare the positive electrode loss rate with a preset second threshold, and diagnose the state of the battery as a positive electrode loss state based on the comparison result.

8. The apparatus for diagnosing batteries according to claim 2, in, The control unit is configured to calculate the negative electrode change rate of the adjusted negative electrode curve, and to calculate the negative electrode loss rate based on the negative electrode change rate and a preset reference negative electrode change rate.

9. The apparatus for diagnosing batteries according to claim 2, in, The control unit is configured to compare the negative electrode loss rate with a preset third threshold, and diagnose the state of the battery as a negative electrode loss state based on the comparison result.

10. The apparatus for diagnosing batteries according to claim 2, in, The control unit is configured to determine a first characteristic value and a second characteristic value based on the adjusted positive electrode curve, and to calculate the capacity loss rate based on the first characteristic value, the second characteristic value and a preset reference difference.

11. The apparatus for diagnosing batteries according to claim 2, in, The control unit is configured to determine a third characteristic value and a fourth characteristic value based on the adjusted negative electrode curve, and to calculate the capacity loss rate based on the third characteristic value, the fourth characteristic value, and a preset reference difference.

12. The apparatus for diagnosing batteries according to claim 2, in, The control unit is configured to compare the capacity loss rate with a preset fourth threshold, and diagnose the state of the battery as a capacity loss state based on the comparison result.

13. A battery pack comprising means for diagnosing the battery according to any one of claims 1 to 12.

14. A vehicle comprising a device for diagnosing a battery according to any one of claims 1 to 12.

15. A method for diagnosing a battery, comprising: The curve acquisition step obtains a battery curve representing the relationship between the battery's voltage and capacity. The curve adjustment step adjusts the preset reference positive electrode curve and reference negative electrode curve to correspond with the battery curve to generate the adjusted positive electrode curve and adjusted negative electrode curve. A diagnostic factor extraction step, wherein the diagnostic factor extraction step extracts diagnostic factors for the battery from at least one of the adjusted positive electrode curve and the adjusted negative electrode curve; as well as A diagnostic step, which diagnoses the state of the battery based on extracted diagnostic factors.

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