KR101835375B1 - Apparatus for estimating state-of-health of battery group and method thereof - Google Patents

Abstract

The present invention provides an apparatus for estimating a health state of a battery group which comprises: a resistance measurement unit for measuring an internal resistance of each battery cell in a group composed of a plurality of battery cells; a battery cell selection unit for selecting a high-resistance battery cell having the largest internal resistance, a low-resistance battery cell having the smallest internal resistance, and an arbitrary battery cell having an arbitrary internal resistance from the group; and a health state estimation unit for measuring a health state of the group by using an internal resistance of the high-resistance battery cell, an internal resistance of the low-resistance battery cell, and an internal resistance of the arbitrary battery cell.

Description

[0001] APPARATUS FOR ESTIMATING STATE-OF-HEALTH OF BATTERY GROUP AND METHOD THEREOF [0002]

The present invention relates to a technique for estimating a health state of a battery group, and more particularly, to an apparatus and method for estimating a health state of a battery group using an internal resistance of a battery group.

In order to build high-voltage and high-capacity applications such as electric vehicles (EV) and energy storage systems (ESS), serial, parallel, and series-parallel combinations of lithium-ion battery cells are required. This is called a battery pack.

Like the unit battery cell, a battery management system (BMS: Battery Management System) is absolutely necessary for stable operation of the battery pack. In such a battery management system, it is required to precisely measure the state of charge (SOC) of the battery cell and the state of health of the battery cell (SOH: State Of Health) and to balance the voltage and charging state of the cells inside the battery pack.

Battery Pack Charged State In terms of precise measurement, an algorithm for estimating the state of charge (SOC) of a battery pack is essential. If the state of charge of the battery pack is correctly checked by the estimation algorithm, it is possible to avoid the degradation of lifetime due to over-charge and over-discharge.

In view of the voltage and charge state balance of the cells inside the battery pack, a screening technique, a unit cell discrimination technique and a balancing technique are currently applied in which a cell having a uniform electrochemical characteristic is selected in advance and a battery pack is constructed. However, the unit cell discrimination technique is costly and time consuming, and the balancing technique has disadvantages in that the circuit design requires an additional cost. Because of these disadvantages, most battery pack manufacturers actually implement unit cell identification techniques simply and minimize balancing techniques.

Battery Cell Health State In terms of precise measurement, the health state of a battery cell is defined by the internal capacitor or internal resistance of the battery cell. In the case of using an internal capacitor, the health state of the battery cell can be expressed as the difference between a full charge discharge capacity and a full discharge discharge capacity and a random discharge capacity and a full discharge discharge capacity. The full discharge capacity is the discharge capacity at the time when the battery cell starts discharging and the full discharge capacity is the discharge capacity in the state where all of the battery cells are discharged to cause aging and the optional discharge capacity means the discharge capacity of the current battery cell do. At this time, the full discharge capacity is defined as 80% of the full discharge capacity.

On the other hand, in the case of using the internal resistance, the health state of the battery cell can be represented by the difference between the internal resistance and the internal internal resistance for the difference between the full internal resistance and the internal internal resistance. The full internal resistance is the internal resistance when the battery cell starts discharging and the internal internal resistance is the internal resistance in the state where all of the battery cells are discharged and aged and the internal resistance is the internal resistance of the current battery cell do. At this time, unlike the global discharge capacity, there is no specific definition as to what standard is defined as the internal resistance. Therefore, it is ambiguous to estimate the health state of the battery cell by the internal resistance of the battery cell. Furthermore, it is also vague to estimate the health status of a battery group or battery pack consisting of a set of battery cells. Since there is no specific definition of internal resistance, it is not known what to choose as a group internal resistance. Since the internal resistance of the group battery cells is different, the health state of the group is changed according to the internal resistance value of the battery cell selected as the internal resistance. Therefore, a reasonable algorithm is needed to estimate health status based on internal resistance. Accordingly, the present invention provides an apparatus and method for estimating a health condition for a population group including a plurality of battery cells.

SUMMARY OF THE INVENTION An object of the present invention is to provide a battery health state estimating apparatus and method using battery cell internal resistance.

Another object of the present invention is to provide an apparatus and method for estimating the health state of a plurality of group groups using the internal resistance of a battery cell when there are a plurality of group groups.

In order to achieve the above object, in one aspect, the present invention provides a battery pack comprising: a resistance measuring unit for measuring an internal resistance of each battery cell in a group consisting of a plurality of battery cells; A battery cell selector for selecting a high-resistance battery cell having the largest internal resistance in the group, a low-resistance battery cell having the smallest internal resistance, and any battery cell having an arbitrary internal resistance; And a health state estimating unit for calculating a health state of the group using the internal resistance of the high resistance battery cell, the internal resistance of the low resistance battery cell, and the internal resistance of the arbitrary battery cell. Thereby providing a health condition estimating device.

According to another aspect of the present invention, there is provided a battery pack comprising: a resistance measuring unit for measuring an internal resistance of each battery cell in a first group and a second group of a plurality of battery cells; A battery cell selector for selecting a high-resistance battery cell having the largest internal resistance in the first group or a second group, a low-resistance battery cell having the smallest internal resistance, and any battery cell having an arbitrary internal resistance; And a health state calculating unit for calculating a health state of the entire group including the first group and the second group using the internal resistance of the high resistance battery cell, the internal resistance of the low resistance battery cell and the internal resistance of the arbitrary battery cell. And an estimating unit for estimating a health state of the battery group.

In another aspect, the present invention provides a method comprising: measuring the internal resistance of each battery cell in a population group consisting of a plurality of battery cells; Selecting a high resistance battery cell having the largest internal resistance in the group; Selecting a low resistance battery cell having the smallest internal resistance in the group; Selecting any of the battery cells having an arbitrary internal resistance in the group; And calculating the health status of the population using the internal resistance of the high resistance battery cell, the internal resistance of the low resistance battery cell, and the internal resistance of the arbitrary battery cell. Estimation method is provided.

In another aspect, the present invention provides a method comprising: measuring the internal resistance of each battery cell in a first group of cells comprising a plurality of battery cells; Measuring an internal resistance of each battery cell in a second group of the plurality of battery cells; Selecting a high resistance battery cell having the largest internal resistance in the first group or the second group; Selecting a low resistance battery cell having the smallest internal resistance in the first group or the second group; Selecting any battery cell having an arbitrary internal resistance in the first group or the second group; And calculating the health status of the entire group including the first group and the second group using the internal resistance of the high resistance battery cell, the internal resistance of the low resistance battery cell, and the internal resistance of the arbitrary battery cell A battery group health state estimating method comprising the steps of:

The present invention provides a health state estimation based on a reasonable internal resistance, thereby providing a health state for a reliable battery group.

In addition, the present invention has an effect of providing a health state for a reliable whole battery group regardless of an estimation object by estimating a health state of a plurality of battery group groups.

1 is a block diagram of a battery group health state estimation system according to an embodiment
2 is a configuration diagram of a battery group group health state estimation system according to another embodiment.
3 is a flow diagram of a battery group health state estimation method in accordance with an embodiment.
4 is a flowchart of a battery group health state estimation method according to another embodiment.

Hereinafter, some embodiments of the present invention will be described in detail with reference to exemplary drawings. It should be noted that, in adding reference numerals to the constituent elements of the drawings, the same constituent elements are denoted by the same reference symbols as possible even if they are shown in different drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

In describing the components of the present invention, terms such as first, second, A, B, (a), and (b) may be used. These terms are intended to distinguish the constituent elements from other constituent elements, and the terms do not limit the nature, order or order of the constituent elements. When a component is described as being "connected", "coupled", or "connected" to another component, the component may be directly connected to or connected to the other component, It should be understood that an element may be "connected," "coupled," or "connected."

1 is a block diagram of a battery group health state estimation system according to an embodiment.

Referring to FIG. 1, a battery group health state estimation system may include a population group 10 and a battery group state health state estimation device 100. [ The group 10 is configured in series and / or in parallel with a plurality of battery cells 10a, 10b, ..., 10n.

The battery health state estimating apparatus 100 may internally include a resistance measuring unit 110, a battery cell selecting unit 120 and a health state estimating unit 130.

The resistance measuring unit 110 measures the internal resistance of each battery cell 10a, 10b, ..., 10n in the group 10 composed of a plurality of battery cells 10a, 10b, ..., 10n. The battery cells 10a, 10b, ..., 10n are modeled as a circuit including a capacitor and a resistor therein. The internal resistance is a resistance included in the modeling circuit of the battery cells 10a, 10b, ..., 10n, the internal capacitor is a capacitor included in the modeling circuit of the battery cells 10a, 10b, ..., 10n, Is the capacitance (capacitance) of the internal capacitor. The internal resistance increases as the battery cells 10a, 10b, ..., 10n are discharged and becomes smaller as the battery cells 10a, 10b, ..., 10n are charged. Conversely, the discharge capacity becomes smaller as the battery cells 10a, 10b, ..., 10n are discharged and becomes larger as the battery cells 10a, 10b, ..., 10n are charged. Therefore, if the discharge capacity or the value of the internal resistance is measured, the current discharge level of the battery cells 10a, 10b, ..., 10n is known. This means that the health status of the battery cells 10a, 10b, ..., 10n can be indirectly measured.

The health states of the battery cells 10a, 10b, ..., 10n through the discharge capacities of the internal capacitors have the relationship of the formula (1).

수식(1)

Equation (1)

는 배터리셀(10a, 10b, ..., 10n)의 건강상태이고,

은 배터리셀(10a, 10b, ..., 10n)의 현재의 방전용량이고,

은 배터리셀(10a, 10b, ..., 10n)의 만방시의 방전용량이고,

은 배터리셀(10a, 10b, ..., 10n)의 만충시의 방전용량이다.here,

Is a health state of the battery cells 10a, 10b, ..., 10n,

Is the current discharge capacity of the battery cells 10a, 10b, ..., 10n,

Is a discharge capacity at the time of full discharge of the battery cells 10a, 10b, ..., 10n,

Is the discharge capacity at full charge of the battery cells 10a, 10b, ..., 10n.

The health states of the battery cells 10a, 10b, ..., 10n through the internal resistors have the relationship of Equation (2).

수식(2)

Equation (2)

는 배터리셀(10a, 10b, ..., 10n)의 건강상태이고,

은 배터리셀(10a, 10b, ..., 10n)의 현재의 내부저항이고,

은 배터리셀(10a, 10b, ..., 10n)의 만방시의 내부저항이고,

은 배터리셀(10a, 10b, ..., 10n)의 만충시의 내부저항이다.here,

Is a health state of the battery cells 10a, 10b, ..., 10n,

Is the current internal resistance of the battery cells 10a, 10b, ..., 10n,

Is an internal resistance when the battery cells 10a, 10b, ..., 10n are fully charged,

Is the internal resistance of the battery cells 10a, 10b, ..., 10n at full load.

는

의 80%로 구체적으로 정의가 되어 있으나,

는 무엇인지 그 정의가 없다. 따라서 내부저항으로 배터리셀(10a, 10b, ..., 10n)의 건강상태를 측정하는 것은 무리일 수 있다.Nevertheless,

The

And 80%

There is no definition of what is. Therefore, it may be difficult to measure the health state of the battery cells 10a, 10b, ..., 10n with the internal resistance.

However, in terms of obtaining the health state of the group 10 composed of the plurality of battery cells 10a, 10b, ..., 10n, the health state estimation method through the internal resistance can be used. The present invention focuses on estimating the health status of the group 10, which is an aggregate thereof, rather than the unit battery cells 10a, 10b, ..., 10n. The resistance measuring unit 110 measures the internal resistance of each battery cell 10a, 10b, ..., 10n to estimate the health state of the group 10. In detail, each battery cell 10a, 10b, ..., 10n is modeled, and the internal resistance, which is the element value of the modeling circuit or the discharge of the internal capacitor, is calculated by using an EIS (Electrochemical Impedance Spectroscopy) Capacity can be obtained.

The battery cell selection unit 120 selects a high resistance battery cell having the largest internal resistance, a low resistance battery cell having the smallest internal resistance, and any battery cell having any internal resistance in the group 10. The battery cell selection unit 120 transmits the internal resistance of the selected high resistance battery cell, the internal resistance of the low resistance battery cell, and the internal resistance of any battery cell to the health state estimator 130.

The health state estimating unit 130 calculates the health state of the population group 10 using the internal resistance of the high-resistance battery cell, the internal resistance of the low-resistance battery cell, and the internal resistance of any battery cell, Estimate the state. The health state estimating unit 130 may calculate the health state estimating unit 130 based on the internal resistance of the high-resistance battery cell, the internal resistance of the low-resistance battery cell, and the internal resistance of any battery cell received from the battery cell selecting unit 120, ) To estimate the health status of the group (10).

수식(3)

Equation (3)

는 집단군(10)의 건강상태이고,

은 집단군(10)의 임의의 배터리셀의 내부저항이고,

은 집단군(10)의 고저항 배터리셀의 내부저항이고,

은 집단군(10)의 저저항 배터리셀의 내부저항이다.here,

Is the health condition of the group 10,

Is the internal resistance of any battery cell of the group 10,

Is the internal resistance of the high resistance battery cell of the group 10,

Is the internal resistance of the low resistance battery cell of the group 10.

의 관계를 가진다. 이 관계는 이하에서 설명할 다른 실시예에서도 공통적으로 적용된다.For reference, the internal resistors selected in the group 10

. This relationship is commonly applied to other embodiments to be described below.

2 is a configuration diagram of a battery group group health state estimation system according to another embodiment.

Referring to FIG. 2, the battery health state estimation system may include a plurality of population groups 10-1, 10-2, ..., 10-n, and a battery group group estimation apparatus 100. FIG. The group of the plurality of groups 10-1, 10-2, ..., 10-n includes a plurality of battery cells 10-1a, 10-1b, 10-1c ..., 10-1n, 10-2a, 10- 10 -nb, 10-nc, ..., 10-nn are formed in serial and /

As described above, in the present embodiment, the battery group group health state estimation apparatus 100 may internally include the resistance measurement unit 110, the battery cell selection unit 120, the health state estimation unit 130, and the like Its function is the same. 10-2, ..., 10-n in the case where there are a plurality of group groups 10, the health state of the whole group 10-1, 10-2, ..., 10-n is estimated. Hereinafter, the first group group 10-1 and the second group group 10-2, which are two group groups, will be described by way of example with reference to this point.

The resistance measuring unit 110 includes a plurality of battery cells 10-1a, 10-1b, 10-1c, ..., 10-1n, 10-2a, 10-2b, 10-2c, ..., 10-2n The internal resistance of each battery cell is measured in the first group 10-1 and the second group 10-2.

The battery cell selection unit 120 selects a high-resistance battery cell having the largest internal resistance in the first group 10-1 or the second group 10-2, a low-resistance battery cell having the smallest internal resistance, And selects any battery cell having an internal resistance. The battery cell selection unit 120 transmits the internal resistance of the selected high resistance battery cell, the internal resistance of the low resistance battery cell, and the internal resistance of any battery cell to the health state estimator 130.

The health state estimating unit 130 estimates the health state of the first group 10-1 and the second group 10-2 using the internal resistance of the high resistance battery cell, the internal resistance of the low resistance battery cell, ) To estimate the health status of the entire group (10-1, 10-2). The health state estimating unit 130 has the internal resistance of the high-resistance battery cell received from the battery cell selecting unit 120, the internal resistance of the low-resistance battery cell, and the internal resistance of any battery cell, And calculate the health status of the whole group (10-1, 10-2).

The health state estimating unit 130 determines that the internal resistance of the battery cell of the first group 10-1 is greater than the internal resistance of the battery cell of the second group 10-2, (10-1, 10-2).

수식(4)

Equation (4)

는 전체 집단군(10-1, 10-2)의 건강상태이고,

은 제1집단군(10-1) 또는 제2집단군(10-2)의 임의의 배터리셀의 내부저항이고,

은 제1집단군(10-1)의 고저항 배터리셀의 내부저항이고,

은 제2집단군(10-2)의 저저항 배터리셀의 내부저항이다.Here, the high-resistance battery cell is selected in the first group 10-1, the low-resistance battery cell is selected in the second group 10-2,

Is the health status of the entire group (10-1, 10-2)

Is the internal resistance of any battery cell of the first group 10-1 or the second group 10-2,

Is the internal resistance of the high-resistance battery cell of the first group 10-1,

Is the internal resistance of the low resistance battery cell of the second group 10-2.

The health state estimating unit 130 may calculate the health state estimating unit 130 based on Equation 5 when the internal resistance of the battery cells of the first group 10-1 is smaller than the internal resistance of the battery cells of the second group 10-2, (10-1, 10-2).

수식(5)

Equation (5)

는 전체 집단군(10-1, 10-2)의 건강상태이고,

은 제1집단군(10-1) 또는 제2집단군(10-2)의 임의의 배터리셀의 내부저항이고,

은 제2집단군(10-2)의 고저항 배터리셀의 내부저항이고,

은 제1집단군(10-1)의 저저항 배터리셀의 내부저항이다.Here, the high-resistance battery cell is selected in the second group 10-2, the low-resistance battery cell is selected in the first group 10-1,

Is the health status of the entire group (10-1, 10-2)

Is the internal resistance of any battery cell of the first group 10-1 or the second group 10-2,

Is the internal resistance of the high resistance battery cell of the second group 10-2,

Is the internal resistance of the low resistance battery cell of the first group 10-1.

The health state estimating unit 130 may calculate the health state estimating unit 130 based on Equation 6 when the internal resistance range of the battery group of the first group group 10-1 includes all of the internal resistance range of the battery group of the second group group 10-2 To estimate the health status of the entire group (10-1, 10-2).

수식(6)

Equation (6)

는 전체 집단군(10-1, 10-2)의 건강상태이고,

은 제1집단군(10-1) 또는 제2집단군(10-2)의 임의의 배터리셀의 내부저항이고,

은 제1집단군(10-1)의 고저항 배터리셀의 내부저항이고,

은 제1집단군(10-2)의 저저항 배터리셀의 내부저항이다.Here, the high-resistance battery cell and the low-resistance battery cell are selected in the first group 10-1,

Is the health status of the entire group (10-1, 10-2)

Is the internal resistance of any battery cell of the first group 10-1 or the second group 10-2,

Is the internal resistance of the high-resistance battery cell of the first group 10-1,

Is the internal resistance of the low resistance battery cell of the first group 10-2.

The health state estimating unit 130 may calculate the health state estimating unit 130 based on the formula 7 when the internal resistance range of the battery cell of the second group 10-2 includes all of the internal resistance range of the battery cell of the first group 10-1 To estimate the health status of the entire group (10-1, 10-2).

수식(7)

Equation (7)

는 전체 집단군(10-1, 10-2)의 건강상태이고,

은 제1집단군(10-1) 또는 제2집단군(10-2)의 임의의 배터리셀의 내부저항이고,

은 제2집단군(10-2)의 고저항 배터리셀의 내부저항이고,

은 제2집단군(10-2)의 저저항 배터리셀의 내부저항이다.Here, the high-resistance battery cell and the low-resistance battery cell are selected in the second group 10-2,

Is the health status of the entire group (10-1, 10-2)

Is the internal resistance of any battery cell of the first group 10-1 or the second group 10-2,

Is the internal resistance of the high resistance battery cell of the second group 10-2,

Is the internal resistance of the low resistance battery cell of the second group 10-2.

3 is a flow diagram of a battery group health state estimation method in accordance with an embodiment.

Referring to FIG. 3, the resistance measuring unit 110 measures the internal resistance of the battery cells 10a, 10b, ..., 10n of the group 10 (S301). The battery cell selection unit 120 selects a high resistance battery cell among the population group 10 (S303). The battery cell selection unit 120 selects a low resistance battery cell among the population group 10 (S305). The battery cell selection unit 120 selects an arbitrary battery cell among the group 10 (S307). The health state estimating unit 130 calculates and estimates the health state of the population 10 using the internal resistance of the selected high resistance battery cell, the internal resistance of the low resistance battery cell, and the internal resistance of any battery cell (S309) .

4 is a flowchart of a battery group health state estimation method according to another embodiment.

4, the resistance measuring unit 110 measures the resistance values of the battery cells 10-1a, 10-1b, 10-1c, ..., 10-2 of the first group 10-1 or the second group 10-2, 10-1n, 10-2a, 10-2b, 10-2c ..., 10-2n are measured (S401). The battery cell selection unit 120 selects a high resistance battery cell among the first group 10-1 or the second group 10-2 (S403). The battery cell selection unit 120 selects a low resistance battery cell among the first group 10-1 or the second group 10-2 (S405). The battery cell selection unit 120 selects an arbitrary battery cell among the first group 10-1 or the second group 10-2 (S407). The health state estimating unit 130 estimates the health state of the first group 10-1 and the second group 10-B using the internal resistance of the selected high resistance battery cell, the internal resistance of the low resistance battery cell, 2) are calculated and estimated (S409).

It is to be understood that the terms "comprises", "comprising", or "having" as used in the foregoing description mean that the constituent element can be implanted unless specifically stated to the contrary, But should be construed as further including other elements. All terms, including technical and scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs, unless otherwise defined. Commonly used terms, such as predefined terms, should be interpreted to be consistent with the contextual meanings of the related art, and are not to be construed as ideal or overly formal, unless expressly defined to the contrary.

The foregoing description is merely illustrative of the technical idea of the present invention, and various changes and modifications may be made by those skilled in the art without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are intended to illustrate rather than limit the scope of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The scope of protection of the present invention should be construed according to the following claims, and all technical ideas within the scope of equivalents should be construed as falling within the scope of the present invention.

Claims (10)

A resistance measuring unit for measuring an internal resistance of each battery cell in a group of a plurality of battery cells;
A battery cell selector for selecting a high-resistance battery cell having the largest internal resistance in the group, a low-resistance battery cell having the smallest internal resistance, and any battery cell having an arbitrary internal resistance; And
A health state estimating unit for calculating a health state of the group using the internal resistance of the high resistance battery cell, the internal resistance of the low resistance battery cell, and the internal resistance of the arbitrary battery cell,
The health status of the group is defined as follows,

here,

Is the health status of the group,

Is the internal resistance of any battery cell in the group,

Is the internal resistance of the high resistance battery cell of the group,

Is the internal resistance of the low-resistance battery cells of the group
A battery group health state estimating device. delete delete A resistance measuring unit for measuring an internal resistance of each battery cell in a first group and a second group including a plurality of battery cells;
A battery cell selector for selecting a high-resistance battery cell having the largest internal resistance in the first group or a second group, a low-resistance battery cell having the smallest internal resistance, and any battery cell having an arbitrary internal resistance; And
Estimating a health condition of the entire group including the first group and the second group using the internal resistance of the high-resistance battery cell, the internal resistance of the low-resistance battery cell, and the internal resistance of the arbitrary battery cell, ≪ / RTI >
When the internal resistance of the first group battery cell is greater than the internal resistance of the second group battery cell, the high resistance battery cell is selected in the first group, the low resistance battery cell is selected in the second group,
The health status of the whole population group is defined as follows,

here,

Is the health status of the whole group,

Is an internal resistance of any battery cell of the first group or the second group,

Is the internal resistance of the high-resistance battery cell of the first group of cells,

Is the internal resistance of the low resistance battery cell of the second group
A battery group health state estimating device. A resistance measuring unit for measuring an internal resistance of each battery cell in a first group and a second group including a plurality of battery cells;
A battery cell selector for selecting a high-resistance battery cell having the largest internal resistance in the first group or a second group, a low-resistance battery cell having the smallest internal resistance, and any battery cell having an arbitrary internal resistance; And
Estimating a health condition of the entire group including the first group and the second group using the internal resistance of the high-resistance battery cell, the internal resistance of the low-resistance battery cell, and the internal resistance of the arbitrary battery cell, ≪ / RTI >
Wherein when the internal resistance of the first group battery cell is less than the internal resistance of the second group battery cell, the high resistance battery cell is selected in the second group, the low resistance battery cell is selected in the first group,
The health status of the whole population group is defined as follows,

here,

Is the health status of the whole group,

Is an internal resistance of any battery cell of the first group or the second group,

Is the internal resistance of the high resistance battery cell of the second group of cells,

Is the internal resistance of the low resistance battery cell of the first group
A battery group health state estimating device. A resistance measuring unit for measuring an internal resistance of each battery cell in a first group and a second group including a plurality of battery cells;
A battery cell selector for selecting a high-resistance battery cell having the largest internal resistance in the first group or a second group, a low-resistance battery cell having the smallest internal resistance, and any battery cell having an arbitrary internal resistance; And
Estimating a health condition of the entire group including the first group and the second group using the internal resistance of the high-resistance battery cell, the internal resistance of the low-resistance battery cell, and the internal resistance of the arbitrary battery cell, ≪ / RTI >
When the internal resistance range of the first group battery cell includes all the internal resistance ranges of the second group battery cell, the high resistance battery cell and the low resistance battery cell are selected in the first group,
The health status of the whole population group is defined as follows,

here,

Is the health status of the whole group,

Is an internal resistance of any battery cell of the first group or the second group,

Is the internal resistance of the high-resistance battery cell of the first group of cells,

Is the internal resistance of the low resistance battery cell of the first group
A battery group health state estimating device. A resistance measuring unit for measuring an internal resistance of each battery cell in a first group and a second group including a plurality of battery cells;
A battery cell selector for selecting a high-resistance battery cell having the largest internal resistance in the first group or a second group, a low-resistance battery cell having the smallest internal resistance, and any battery cell having an arbitrary internal resistance; And
Estimating a health condition of the entire group including the first group and the second group using the internal resistance of the high-resistance battery cell, the internal resistance of the low-resistance battery cell, and the internal resistance of the arbitrary battery cell, ≪ / RTI >
When the internal resistance range of the second group battery cell includes all the internal resistance ranges of the first group battery cell, the high resistance battery cell and the low resistance battery cell are selected in the second group group,
The health status of the whole population group is defined as follows,

here,

Is the health status of the whole group,

Is an internal resistance of any battery cell of the first group or the second group,

Is the internal resistance of the high resistance battery cell of the second group of cells,

Is the internal resistance of the low resistance battery cell of the second group
A battery group health state estimating device. Measuring the internal resistance of each battery cell in a group of a plurality of battery cells;
Selecting a high resistance battery cell having the largest internal resistance in the group;
Selecting a low resistance battery cell having the smallest internal resistance in the group;
Selecting any of the battery cells having an arbitrary internal resistance in the group; And
Computing the health state of the population using the internal resistance of the high resistance battery cell, the internal resistance of the low resistance battery cell, and the internal resistance of the arbitrary battery cell,
The health status of the group is defined as follows,

here,

Is the health status of the group,

Is the internal resistance of any battery cell in the group,

Is the internal resistance of the high resistance battery cell of the group,

Is the internal resistance of the low-resistance battery cells of the group
The method comprising the steps of: delete delete

Images