KR102091771B1 - Apparatus and method for counting a cycle of a battery - Google Patents

Abstract

The present invention relates to a battery cycle counting device and method. A battery cycle counting apparatus according to an embodiment of the present invention includes a memory storing a correction table indicating a correlation between predetermined battery parameters for a battery and corresponding weights; A measurement unit coupled to the battery and outputting battery information including measurement values for each of the battery parameters every predetermined period; A calculator configured to calculate an additional current amount indicating the degree of use of the battery during the current period based on the battery information; A correction unit that obtains weights corresponding to at least some of the measured values from the correction table and corrects the additional current amount using the obtained weights; An updating unit updating the accumulated current amount indicating the degree of total use of the battery until the current period based on the corrected additional current amount; And a counting unit determining whether to increase the value of the cycle count of the battery based on a result of comparing the predetermined reference current amount with the updated accumulated current amount.

Description

Battery cycle counting device {Apparatus and method for counting a cycle of a battery}

The present invention relates to an apparatus and method for counting cycles of a battery, and more particularly, to an apparatus and method for accurately counting a battery cycle based on an amount of current according to charging and discharging of the battery.

In recent years, as demand for portable electronic products such as laptops, video cameras, and portable telephones has rapidly increased, and electric vehicles, energy storage batteries, robots, and satellites have been developed in earnest, high-performance secondary batteries capable of repeated charging and discharging are possible. Research is actively underway.

Currently commercialized secondary batteries include nickel cadmium batteries, nickel hydrogen batteries, nickel zinc batteries, and lithium secondary batteries. Among these, lithium secondary batteries have little memory effect compared to nickel-based secondary batteries, and thus charge / discharge. This free, self-discharge rate is very low, and it is spotlighted for its high energy density.

For stable use of various devices or systems that receive energy from a battery, accurate information about the state of charge (SOC) of the battery is essential. In particular, the SOC is a measure of how long the battery can be used, so it is very important information for the user to use the device. For example, battery-equipped devices such as laptops, cell phones, and automobiles estimate SOC, and provide the user with information converted by using the estimated SOC as an available time.

In general, SOC of a battery in which the remaining capacity relative to the reference capacity is expressed as a percentage may be largely classified into an ASOC (Absolute SOC) and a RSOC (Relative SOC). ASOC is a value representing the ratio of Remain Capacity (RC) to design capacity (DC) of the battery, and RSOC is the ratio of the remaining capacity to the full charge capacity (FCC) of the battery. It is a value to indicate.

Here, the full charge capacity represents the maximum amount of charge that the battery can actually accommodate. Unlike the design capacity, it gradually decreases as the battery charges and discharges are repeated, so it is updated to a new value each time the battery is fully charged or fully discharged. It also becomes.

The cycle count of the battery is a value indicating the number of times the battery has been charged and discharged. For example, each time the battery is discharged by a full charge capacity, the cycle count of the battery is increased by one. How often the battery has been charged and discharged is one of the most important data in the use of the battery, so it is necessary to accurately calculate the cycle count.

Conventionally, a technique of accumulating a value of a discharge capacity obtained by simply integrating a charge / discharge current of a battery and dividing the accumulated value by a value of a predetermined reference capacity to update the previous cycle count is used.

Depending on the battery usage environment (eg, SOC, temperature), an error may occur between the value of the charge / discharge current measured by the current sensor coupled to the battery and the value of the actual charge / discharge current. It may continue to accumulate over time. However, most of the prior arts take a method of counting cycles of a battery based only on a value obtained by integrating a charge / discharge current without proper consideration of the environment in which the battery is used. As a result, there is a problem in that an inaccurate cycle count value reflecting the accumulated error is notified to the user.

The present invention has been devised to solve the above problems, and based on the measured values of a plurality of parameters related to the battery, by appropriately correcting the amount of current according to charging and discharging of the battery by cycle, the cycle count of the battery It is an object of the present invention to provide a battery cycle counting device and method for accurately calculating a value.

Other objects and advantages of the present invention can be understood by the following description, and will be more clearly understood by examples of the present invention. In addition, it will be readily understood that the objects and advantages of the present invention can be realized by means and combinations thereof.

A battery cycle counting apparatus according to an aspect of the present invention for achieving the above object includes: a memory storing a correction table indicating a correlation between predetermined battery parameters for a battery and corresponding weights; A measurement unit coupled to the battery and outputting battery information including measurement values for each of the battery parameters every predetermined period; A calculator configured to calculate an additional current amount indicating the degree of use of the battery during the current period based on the battery information; A correction unit that obtains weights corresponding to at least some of the measured values from the correction table and corrects the additional current amount using the obtained weights; An updating unit updating the accumulated current amount indicating the degree of total use of the battery until the current period based on the corrected additional current amount; And a counting unit determining whether to increase the value of the cycle count of the battery based on a result of comparing the predetermined reference current amount with the updated accumulated current amount.

Preferably, the predetermined battery parameters may include charge and discharge current, temperature, and SOC of the battery. In some cases, the correction table may include: a first sub-table indicating a correlation between a plurality of predetermined SOC periods and weights corresponding thereto; A second sub-table showing a correlation between a plurality of predetermined charge / discharge rate intervals and corresponding weights; And a third sub-table indicating a correlation between a plurality of predetermined temperature intervals and weights corresponding thereto.

In addition, the correction unit acquires a first weight corresponding to a section to which the measured SOC belongs, among a plurality of SOC sections of the first sub table, from the first sub table, and a plurality of charges of the second sub table. Among the discharge rate periods, a second weight corresponding to a section to which a charge / discharge rate corresponding to the measured charge / discharge current belongs is obtained from the second sub table, and the measured temperature among a plurality of temperature sections of the third sub table The third weight corresponding to the section to which it belongs may be obtained from the third sub table. In this case, the correction unit may correct the additional current amount using the first weight, the second weight, and the third weight.

Preferably, the counting unit may increase the value of the cycle count by a predetermined value whenever the updated cumulative current amount increases by the reference current amount.

Energy storage system according to another aspect of the present invention, the battery cycle counting device described above; And at least one battery pack coupled to the battery cycle counting device.

A battery cycle counting method according to another aspect of the present invention includes: storing a correction table indicating a correlation between predetermined battery parameters and corresponding weights for a battery; Outputting battery information including measurement values for each of the battery parameters every predetermined period; Calculating, based on the battery information, an additional amount of current indicating the degree to which the battery has been used during the current period; Obtaining weights corresponding to at least some of the measured values from the correction table; Correcting the amount of additional current using the obtained weights; Updating, based on the corrected additional current amount, a cumulative current amount indicating the degree of total use of the battery until the current period; And determining whether to increase the value of the cycle count of the battery, based on a result of comparing the predetermined reference current amount with the updated cumulative current amount.

Preferably, the predetermined battery parameters may include charge and discharge current, temperature, and SOC of the battery. In this case, the correction table may include: a first sub-table indicating a correlation between a plurality of predetermined SOC periods and corresponding weights; A second sub-table showing a correlation between a plurality of predetermined charge / discharge rate intervals and corresponding weights; And a third sub-table indicating a correlation between a plurality of predetermined temperature intervals and weights corresponding thereto.

In addition, the obtaining of the weights may include: obtaining a first weight corresponding to a section to which the measured SOC belongs from among the plurality of SOC sections of the first sub table from the first sub table; Obtaining a second weight corresponding to a section to which a charge / discharge rate corresponding to the measured charge / discharge current belongs among a plurality of charge / discharge rate sections of the second sub table from the second sub table; And obtaining a third weight corresponding to a section to which the measured temperature belongs, among a plurality of temperature sections of the third sub table, from the third sub table. In this case, the step of correcting the additional current amount may include correcting the additional current amount using the first weight, the second weight, and the third weight.

The method may further include increasing the value of the cycle count by a predetermined value whenever the updated cumulative current amount increases by the reference current amount.

Specific details of other embodiments are included in the detailed description and drawings.

According to at least one of the embodiments of the present invention, based on the measured values of a plurality of parameters related to the battery, the current amount according to charging and discharging of the battery is appropriately corrected periodically, and based on the corrected amount of current of the battery By calculating the value of the cycle count, there is an advantage that more accurate cycle counting results can be provided.

The effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description of the claims.

The following drawings attached to this specification are intended to illustrate preferred embodiments of the present invention, and serve to further understand the technical idea of the present invention together with the detailed description of the invention described below, and thus the present invention is described in such drawings. It is not limited to interpretation.
1 is a block diagram schematically showing a functional configuration of a battery cycle counting device according to an embodiment of the present invention.
2 to 4 schematically show sub-tables included in a correction table according to an embodiment of the present invention.
FIG. 5 is a flowchart schematically showing a method of calculating a value of a cycle count of a battery by the battery cycle counting device illustrated in FIG. 1.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, the terms or words used in the present specification and claims should not be construed as being limited to ordinary or lexical meanings, and the inventor appropriately explains the concept of terms to explain his or her invention in the best way. Based on the principle that it can be defined, it should be interpreted as meanings and concepts consistent with the technical spirit of the present invention.

Therefore, the configuration shown in the embodiments and drawings described in this specification is only one of the most preferred embodiments of the present invention and does not represent all of the technical spirit of the present invention. It should be understood that there may be equivalents and variations.

In addition, in the description of the present invention, when it is determined that detailed descriptions of related well-known structures or functions may obscure the subject matter of the present invention, detailed descriptions thereof will be omitted.

Throughout the specification, when a part “includes” a certain component, this means that other components may be further included, rather than excluding other components, unless otherwise specified. In addition, terms such as “unit” described in the specification mean a unit that processes at least one function or operation, and may be implemented by hardware or software, or a combination of hardware and software.

In addition, throughout the specification, when a part is "connected" to another part, it is not only "directly connected" but also "indirectly connected" with another element in between. Includes.

Hereinafter, a battery cycle counting device according to an embodiment of the present invention will be described.

1 is a block diagram schematically showing a functional configuration of a battery cycle counting device 100 according to an embodiment of the present invention.

Referring to FIG. 1, the battery cycle counting device 100 includes a memory 110, a measurement unit 120, a calculation unit 130, a correction unit 140, an update unit 150, and a counting unit 160 can do. Any one of the above components may be operably connected to at least another one. Further, the battery 10 may be one battery cell, or two or more battery cells may be connected in series or in parallel.

The memory 110 may store various data and commands required for the overall operation of the battery cycle counting device 100. For example, the memory 110 includes a flash memory type, a hard disk type, a solid state disk type, an SDD type (Silicon Disk Drive type), and a multimedia card micro type. micro type (RAM), random access memory (RAM), static random access memory (SRAM), read-only memory (ROM), electrically erasable programmable read-only memory (EPMROM), programmable read-only memory (PROM) It may include at least one type of storage medium.

The memory 110 may store at least a correction table. The correction table may be pre-written in a look up table (LUT) format or the like and stored in the memory 110. Here, the correction table may indicate a correlation between predetermined battery parameters for the battery 10 and weights corresponding thereto. Further, the correction table may include a sub-table for each battery parameter. For example, when there are three types of predetermined battery parameters, three sub-tables for each of the three types of battery parameters may be included in the correction table. Of course, information processed by other components included in the battery cycle counting device 100 or data related thereto may be temporarily or permanently stored in the memory 110.

The measurement unit 120 may be combined with the battery 10 to output battery information of the battery 10. Here, the battery information may include at least measurement values for each of the battery parameters. Preferably, the measurement unit 120 may be configured to measure the battery information every predetermined period. At this time, each measurement value may be an average value for a specific period. Alternatively, each measurement value may be a value measured at a specific time point within a specific period.

In addition, the time length for each cycle is a fixed value or a changeable value, and may be appropriately set according to a device 100 in which the battery 10 is used or an environment in which the battery 10 is installed, and according to a user's need can be changed. Preferably, the measurement unit 120 may adjust the time length for each period according to a rate of change of at least one of the measured values for the battery parameters. For example, when the measured value of the charge / discharge current of the battery rapidly increases or decreases within the time limit, the measurement unit 120 may decrease the time length for each period.

The measurement unit 120 may include at least one sensor that measures at least one of a charge / discharge current, a terminal voltage, and a temperature of the battery 10 while the battery 10 is being charged or discharged.

Specifically, the measurement unit 120 may include a current sensor for measuring the charging and discharging current of the battery 10, a voltage sensor for measuring the terminal voltage of the battery 10, and a temperature sensor for measuring the temperature of the battery 10. You can. The temperature sensor may be configured to be attached directly to the battery 10 or may be configured to be spaced apart from the battery 10 by a predetermined interval.

The voltage sensor may measure a voltage applied to both ends of the battery 10 while the battery 10 is being used, that is, while the battery 10 is being charged or discharged.

The current sensor may measure the charging and discharging current of the battery 10 while charging or discharging of the battery 10 is in progress. In addition, the current sensor may measure a charge / discharge rate based on a current when charging or discharging the battery 10. The charge / discharge rate may be referred to as a 'C-rate'. At this time, the charge / discharge rate is a value obtained by dividing the discharge current or charge current of the battery 10 by the rated capacity value minus the unit, and the unit may be C.

To this end, the memory 110 may further include data indicating the design capacity of the battery 10. For example, when the design capacity is 1000mAh, the discharge current is 100mA, the charge and discharge rate is 0.1C, the discharge current is 500mA, the charge and discharge rate is 0.5C, and the discharge current is 1000mA, the charge and discharge rate can be measured as 1C. In this case, the discharge current may be a value measured at a specific time. Alternatively, the discharge current may be an average of discharge current values measured multiple times during a predetermined time period. Of course, the same method can be applied to the charging current.

The measurement unit 120 may include a sensor that measures the time when the battery 10 is used. For example, the measurement unit 120 may include a Real Time Clock (RTC) and a Real Time Clock (RTC) may measure the time the battery 10 is used. In the present invention, that the battery 10 is used may mean at least one of a state in which the battery 10 is being discharged or being charged. In other words, if none of the charging and discharging of the battery 10 proceeds, it may mean that the battery 10 is not in use.

The measurement unit 120 may measure the SOC of the battery 10 based on at least some of the measured values for each of the battery parameters. For example, the measurement unit 120 may estimate the SOC of the battery 10 every predetermined period by using the extended Kalman filter, and output data indicating the estimated SOC. Data representing the estimated SOC may be included in the battery information. Since the principle of the extended Kalman filter is well known to those skilled in the art, a detailed description thereof will be omitted.

The calculation unit 130 may receive battery information from the measurement unit 120. The calculator 130 may calculate an additional current amount indicating the degree of use of the battery 10 for each period, based on at least a part of the received battery information. That is, the additional current amount may be a value obtained by summing the discharge current amount and the charging current amount of the battery 10 during the current period. More specifically, the additional current amount may represent a value obtained by summing a value obtained by turning the current charged in the battery 10 from the start time to the end time of the current cycle and a value obtained by integrating the current discharged from the battery 10. have.

Specifically, the calculator 130 may integrate the charge / discharge current of the battery 10 during the current period, and set the accumulated current amount as the additional current amount. In this case, the unit of the additional current amount may be Ah.

For example, suppose the time length per cycle is 1 second. If neither of the charging and discharging of the battery 10 has progressed during one cycle, the amount of additional current measured by the measuring unit 120 may be 0 Ah. If the charging or discharging of the battery 10 is performed for a very short time during the corresponding period, the additional current amount measured by the measuring unit 120 will be a value greater than 0 Ah.

The correction unit 140 may obtain weights corresponding to at least some of the measured values from the correction table stored in the memory 110. In addition, when receiving the data representing the amount of the additional current from the calculator 130, the correction unit 140 may correct the amount of the additional current using the obtained weights. For various examples of correcting the amount of additional current, it will be described later in more detail with reference to FIGS. 2 to 4.

The update unit 150 may receive data indicating the corrected additional current amount from the correction unit 140. The updating unit 150 may update the accumulated current amount indicating the degree to which the battery 10 has been used up to the current period, based on the corrected additional current amount. That is, the accumulated amount of power is supplied to the battery 10 by the amount of current supplied to the outside by the discharge of the battery 10 and the charging of the battery 10 from the time the battery 10 is shipped to the end of the current cycle. It may be a value obtained by summing the amount of current supplied. In the memory 110, data indicating an accumulated current amount up to a previous cycle may be already stored.

For example, assuming that the n-th cycle is currently in progress, the accumulated current amount up to the (n-1) -th cycle A in the memory 110 may be already stored. If, in the nth period, the additional current amount calculated by the calculator 130 is a, and the additional current amount corrected by the correction unit 140 is a ', the updated accumulated current amount is the (n-1) th cycle It may be equal to (A + a '), which is the sum of the cumulative current amount up to A and the corrected additional current amount a' of the nth period.

Also, the update unit 150 may store data indicating the updated accumulated current amount in the memory 110. In other words, whenever the accumulated current amount is updated, the update unit 150 may store data indicating the updated accumulated current amount in the memory 110. That is, the update unit 150 may store data representing a new current amount in the memory 110 every predetermined period.

The counting unit 160 may receive data indicating the updated cumulative current amount from the memory 110 or the updating unit 150. Further, the counting unit 160 may compare the reference current amount and the updated cumulative current amount.

The reference current amount may be a value that can be expressed by Ah in the same manner as the unit current amount and the accumulated current amount. In addition, the reference current amount is a value corresponding to the capacity used when the full charge and full discharge of the battery 10 are repeated at least once under a predetermined condition, and may be determined in advance through experiments or simulations.

For example, through the experiment, based on the result of performing a full charge and a full discharge of the battery 10 with a design current at a normal temperature (eg, 25 ° C.) over a predetermined number of times, the SOC of the battery 10 is 0 A reference current amount indicating the sum of the charge current amount accumulated from% to 100% and the discharge current amount accumulated from SOC to 100% to 0% can be determined. Depending on the implementation, the reference amount may be updated according to a predetermined rule when the value of the battery cycle of the battery increases. Preferably, whenever the value of the battery cycle increases by a predetermined value, the counting unit 160 may reduce the reference current amount by a predetermined ratio. For example, suppose that the first reference current amount is 1000 Ah, and a rule is defined to deduct 1% of the reference current amount every time the value of the battery cycle increases by 100. If the value of the battery cycle is 100, the counting unit 160 may change the reference current amount from 1000 Ah to 990 Ah. Thereafter, when the value of the battery cycle reaches 200, the counting unit 160 may change the reference current amount from 990 Ah to 980.1 Ah.

Data indicating the reference current amount may be previously stored in at least one of the counting unit 160 and the memory 110.

Also, the counting unit 160 may determine whether to increase the value of the cycle count of the battery 10 based on the result of the comparison. Preferably, the counting unit 160 may increase the value of the cycle count by a predetermined value whenever the updated cumulative current amount increases by the reference current amount.

For example, the reference current amount is 100mAh, the accumulated current amount updated in the (n-2) th cycle is 5000mAh, and whenever the updated accumulated current amount increases by the reference current amount, the value of the cycle count is increased by the predetermined value P. Assume that it is set. For example, P may be 1. In this case, the cycle count at the end of the (n-2) th cycle will be (5000mAh / 100mAh) × P = 50. If the corrected additional current amount of the (n-1) th period, which is the cycle immediately following the (n-2) th period, is 50mAh, the accumulated current amount will be updated to 5000mAh + 50mAh = 5050mAh. In this case, the cumulative current amount up to the (n-1) th period is increased by 50 mAh from the cumulative current up to the (n-2) th period, which is smaller than the reference current amount of 100 mAh, so the counting unit 160 is ( At the end of the n-1) th cycle, the cycle count can be maintained at the same 50 as before. Thereafter, if the corrected additional current amount of the n-th period, which is the cycle immediately following the (n-1) -th period, is 100 mAh, the accumulated current amount will be updated to 5050 mAh + 100 mAh = 5150 mAh. In this case, the cumulative current amount up to the n-th period is increased by 150 mAh than the cumulative current amount up to the (n-2) -th period, which is greater than the reference current amount of 100 mAh, so the counting unit 160 ends the n-th period At the time, the cycle count can be increased from 50 to 51.

The above-described calculation unit 130, correction unit 140, update unit 150, and counting unit 160 are hardware, respectively, ASICs (application specific integrated circuits), DSPs (digital signal processors), DSPDs (digital signal) It can be implemented using at least one of processing devices, programmable logic devices (PLDs), field programmable gate arrays (FPGAs), micro-controllers, microprocessors, and electrical units for performing other functions. . Alternatively, at least two of the calculation unit 130, the correction unit 140, the update unit 150, and the counting unit 160 may be integrally implemented using a single hardware means.

Meanwhile, FIG. 1 shows that one of the components is connected to the other through at least one connection line. However, this is exemplary, and the actual implementation between the components of the battery cycle counting device 100 should not be understood as being limited by the connection line shown in FIG. 1.

In addition, some of the components of the battery cycle counting device 100 shown in FIG. 1 may be omitted from the battery cycle counting device 100. Accordingly, the battery cycle counting device 100 may be configured to have fewer components than those listed above, or to further include additional components not listed above.

The battery cycle counting device 100 according to the present invention may be implemented in a form included in a battery pack coupled thereto. That is, the battery pack according to the present invention may include a battery cycle counting device 100.

Further, the battery cycle counting device 100 according to the present invention may be included in a small device such as a mobile phone. Alternatively, the battery cycle counting device 100 may be included in a medium- or large-sized device such as a vehicle or an energy storage system (ESS). In particular, since the electric vehicle including the hybrid vehicle is supplied with the driving power of the motor by the battery 10, it is very important to accurately count the cycle of the battery 10.

2 to 4 schematically show sub-tables included in a correction table according to an embodiment of the present invention.

First, FIG. 2 illustrates the first sub table 111. In the present invention, the first sub-table 111 may be a table showing a correlation between a plurality of predetermined SOC periods and corresponding weights.

Looking at it, SOC sections of the first sub-table 111 are divided into a total of 10, 10% from 0% to 100%. In addition, the weights of the first sub-table 111 are also divided into a total of 10. In the first sub-table 111, it can be seen that any one weight is related to any one SOC section. In addition, in the first sub-table 111, it can be confirmed that any one SOC section has a relationship corresponding to any one weight.

In addition, in the first sub-table 111, a weight of a relatively small value may be created to have a correlation corresponding to a SOC section of a relatively low value. For example, the weight corresponding to the SOC section of 0 to 10% is 0.8, while the weight corresponding to the SOC section of 10 to 20%, which is relatively high, may be 0.85 greater than 0.8.

Next, FIG. 3 illustrates the second sub table 112. In the present invention, the second sub-table 112 may be a table indicating a correlation between a plurality of predetermined charge / discharge rate intervals and corresponding weights.

Looking at it, the charge / discharge rate intervals of the second sub-table 112 are divided into a total of 10 from 0 C to 1C by 0.1C. In addition, the weights of the second sub-table 112 are also divided into 10. In the second sub-table 112, it can be confirmed that any one weight has a relationship corresponding to any one charge / discharge rate section. In addition, in the second sub-table 112, it can be confirmed that any one charge / discharge rate interval has a relationship corresponding to any one weight.

In addition, in the second sub-table 112, a weight of a relatively small value may be created to have a correlation corresponding to a charge / discharge rate section of a relatively low value. For example, while the weight corresponding to the charge-discharge rate section of 0.5 to 0.6C is 1.1, the weight corresponding to the relatively high charge-discharge rate section of 0.6 to 0.7% may be 1.2, which is greater than 1.1.

Subsequently, FIG. 4 illustrates the third sub table 113. In the present invention, the third sub-table 113 may be a table showing a correlation between a plurality of predetermined temperature sections and weights corresponding thereto.

Looking at it, the temperature sections of the third sub-table 113 are divided into a total of 7 pieces each of -10 ° C to 60 ° C by 10 ° C. In addition, the weights of the third sub table 113 are also divided into a total of seven. In the third sub table 113, it can be confirmed that any one weight is related to any one temperature range. In addition, in the second sub-table 112, it can be confirmed that any one of the temperature sections has a relationship corresponding to any one of the weights.

In addition, in the third sub-table 113, a weight corresponding to a temperature section relatively distant from the appropriate temperature section may be created to have a greater correlation than a weight corresponding to a temperature section relatively close to the appropriate temperature section. . For example, assuming that the appropriate temperature range is 20 to 30 ° C, the weight corresponding to the temperature range of 10 to 20 ° C relatively close to the appropriate temperature range is 1.1, while 0 to relatively distant from the appropriate temperature range. The weight corresponding to the temperature range of 10 ° C is 1.3, which is greater than 1.1.

Preferably, each section of the first to third sub tables 111, 112, and 113 may be set so as not to overlap with the section adjacent thereto. Also, the first to third sub-tables 111, 112, and 113 may be created in the form of a look up table.

Meanwhile, the first to third sub tables 111, 112, and 113 are not limited to the examples illustrated in FIGS. 2 to 4. For example, although the range of one section of the first sub-table 111 is shown to be the same as that of the other section, it may have different ranges for each section. As another example, the third sub-table 113 is composed of a total of seven temperature sections, but may be changed to consist of more or fewer temperature sections as needed.

Hereinafter, a method of counting the number of cycles of the battery 10 by the battery cycle counting device 100 will be described in detail with reference to FIGS. 1 to 4. For convenience of description, it is assumed that the current cycle is the n-th cycle. In addition, the symbol '[]' used in Equations 1 and 2 below denotes a floor function. That is, when x is a real number, [x] is the largest integer not greater than x.

Specifically, when a predetermined condition is satisfied, the battery cycle counting device 100 may set the unit of the additional current amount to Ah. Preferably, if the condition that the terminal voltage of the battery 10 being charged and discharged is within a predetermined error range (eg, ± 3%) from the design voltage (eg, 4V), the battery cycle counting device 100 is added The unit of amperage can be set to Ah.

The battery cycle counting apparatus 100 may calculate the value of the cycle count of the battery 10 using Equation 1 below.

Here, CC _n is the value of the cycle count at the end of the nth cycle, Q _ref is the reference current amount, C _k is the additional current amount of the kth period, H1 _k is the first weight of the kth period, H2 _k Is the second weight of the k-th period, and H3 _k is the third weight of the k-th period. As described above, the calculator 130 can calculate C _k based on the battery information.

In addition, C _n 'is a value obtained by correcting C _n using H1 _n , H2 _n and H3 _n . The correction unit 140 obtains H1 _n , H2 _n and H3 _n from each of the first to third sub tables 111, 112, and 113. Then, the correction unit 140 may calculate C _n ′ by multiplying all of C _n , H1 _k , H2 _k, and H3 _k . That is, C _n corrected by H1 _n , H2 _n and H3 _n is C _n '.

In addition, D _{n -1} is an accumulated current amount up to the (n-1) th period, and may be stored in the memory 110 before the n th period starts. In addition, D _n is the cumulative current amount up to the n-th cycle. That is, D _n is the _sum of D _{n - 1} and C _n '. In other words, the value obtained by updating D _{n - 1} using C _n 'is D _n .

For example, suppose that Q _ref is 4000mAh, D _{n -1} is 198000mAh, and C _n is 1300mAh. The cycle count at the end of the (n-1) th cycle, CC _{n - 1,} would have been [198000mAh / 4000mAh] = [49.5] = 49. If, in the n-th cycle, the SOC of the battery 10 is 65%, the charge / discharge rate is 0.25C, and the temperature is -5 ° C, the correction unit 140 belongs to 65% from the first sub-table 111. The weight corresponding to the SOC section, 1.2, can be obtained. Accordingly, H1 _n may be set to 1.2. In addition, the correction unit 140 may obtain a weight of 0.9 corresponding to the charge / discharge rate section to which 0.25C belongs from the second sub table 112. Accordingly, H2 _n may be set to 0.9. In addition, the correction unit 140 may obtain a weight of 1.5 corresponding to a temperature range to which -5 ° C belongs from the third sub table 113. Accordingly, H3 _n may be set to 1.5. Next, correction section 140 may calculate the C _{n 'n} is multiplied by the H1, H2 and H3 _{n n} to C _n. Accordingly, C _n ′ becomes 2106mAh, and D _n becomes 200106mAh. Therefore, CC _n calculated by the counting unit 160 is [200106mAh / 4000mAh] = 50, which is a value greater than CC _{n -1} by one.

On the other hand, the battery cycle counting apparatus 100 according to another embodiment of the present invention, instead of using a single reference current amount as in Equation 1, two different criteria for each of the charging and discharging operations of the battery 10 Using the current amount, the cycle count of the battery 10 can be calculated.

Hereinafter, the two different reference current amounts will be referred to as 'reference discharge capacity' and 'reference charge capacity', respectively. The 'reference discharge capacity' and the 'reference charge capacity' may be values determined in advance through prior experiments. For example, at room temperature (eg, 25 ° C.), SOC of the battery 10 is 0% to 100% based on the result of performing a full charge and a full discharge to the battery 10 over a predetermined number of times with a design current. The accumulated amount of current until is set as the reference charging capacity, and the accumulated amount of current until the SOC of the battery 10 is from 100% to 0% can be determined as the reference discharge capacity.

The battery cycle counting apparatus 100 may calculate the value of the cycle count of the battery 10 using Equation 2 below.

Here, CC _n is the value of the cycle count at the end of the nth cycle, Q1 _ref is the reference discharge capacity, and Q2 _ref is the reference charge capacity. The calculator 130 may calculate the discharge current and the charging current for each cycle based on the battery information. In addition, C1 _k is an additional discharge current amount indicating a value obtained by integrating the discharge current of the battery 10 during the kth period, and C2 _k is an additional charge current amount indicating a value obtained by integrating the charging current of the battery 10 during the kth period. to be.

Also, J1 _k , J2 _k and J3 _k are weights obtained from the first to third sub tables 111, 112 and 113 during discharge of the k-th cycle in order. In addition, _k R1, _k R2 and R3 are the weight _k is the order that is obtained from the first to third sub-table (111, 112, 113) during filling of the k-th cycle.

The correction unit 140 obtains the J1 _n , J2 _n , J3 _n , R1 _n , R2 _n and R3 _n from each of the first to third sub tables 111, 112 and 113. Then, the correction unit 140 may calculate C1 _n 'by multiplying all of C1 _n , J1 _n , J2 _n, and J3 _n . That is, C1 _n corrected by J1 _n , J2 _n and J3 _n is C1 _n '. At the same time or separately, the correction unit 140 may calculate C2 _n 'by multiplying all of C2 _n , R1 _n , R2 _n and R3 _n . That is, C2 _n corrected by R1 _n , R2 _n and R3 _n is C2 _n '.

Further, D1 _{n -1} is the cumulative discharge amount up to the (n-1) th cycle, and D2 _{n -1} is the cumulative charge amount up to the (n-1) th cycle, each of which is before the nth period starts. It may be stored in the memory 110.

In addition, D1 _n is the cumulative discharge amount up to the nth cycle. That is, D1 _n is the _sum of D1 _{n - 1} and C1 _n '. In other words, the value D1 _{n - 1} updated by using C1 _n 'is D1 _n . In addition, D2 _n is the cumulative charge amount up to the nth cycle. That is, D2 _n is the _sum of D2 _{n - 1} and C2 _n '. In other words, the value of D2 _{n - 1} updated using C2 _n 'is D2 _n .

For example, suppose that Q1 _ref is 1900mAh, Q2 _ref is 2100mAh, D1 _{n -1} is 94000mAh, D2 _{n -1} is 104000mAh, C1 _n is 600mAh, and C2 _n is 700mAh. In this case, CC _{n - 1, which} is the cycle count at the end of the (n-1) th cycle, would have been [94000mAh / (2 × 1900mAh) + 10400mAh / (2 × 2100mAh)] = 49.

If, during the nth cycle, the battery 10 is discharged, if the SOC of the battery 10 is 65%, the charge and discharge rate is 0.25C, and the temperature is -5 ° C, the correction unit 140 first sub table From (111), a weight corresponding to SOC section to which 65% belongs can be obtained 1.2. Accordingly, J1 _n may be set to 1.2. In addition, the correction unit 140 may obtain a weight of 0.9 corresponding to the charge / discharge rate section to which 0.25C belongs from the second sub table 112. Accordingly, J2 _n may be set to 0.9. In addition, the correction unit 140 may obtain a weight of 1.5 corresponding to a temperature range to which -5 ° C belongs from the third sub table 113. Accordingly, J3 _n may be set to 1.5. Next, correction section 140 may calculate the C1 _{n 'n} is multiplied by the J1, J2 and J3 _{n n} the _n C1. Accordingly, C1 _n 'becomes 972mAh, and D1 _n becomes 94972mAh.

If the battery 10 is being charged in the n-th cycle, the SOC of the battery 10 is 55%, the charge / discharge rate is 0.45C, and the temperature is -5 ° C, the correction unit 140 first sub-table From (111), a weight corresponding to an SOC section to which 55% belongs can be obtained. Accordingly, R1 _n may be set to 1. In addition, the correction unit 140 may obtain a weight corresponding to a charging / discharging rate section to which 0.45C belongs, from the second sub table 112. Accordingly, R2 _n may be set to 1. In addition, the correction unit 140 may obtain a weight of 1.5 corresponding to a temperature range to which -5 ° C belongs from the third sub table 113. Accordingly, R3 _n may be set to 1.5. Next, correction section 140 may calculate the C2 _{n 'n} is multiplied by R1, R2 and R3 _{n n} the _n C2. Accordingly, C2 _n 'becomes 1050mAh, and D2 _n becomes 105500mAh.

Therefore, CC _n calculated by the counting unit 160 is [94972mAh / (2 × 1900mAh) + (105500mAh / (2 × 2100mAh)] = 50, which is a value increased by ₁ than CC _{n -1} .

5 is a flowchart schematically showing a method of calculating the value of the cycle count of the battery 10 by the battery cycle counting device 100 illustrated in FIG. 1.

Referring to FIG. 5, in step S510, the battery cycle counting device 100 stores the correction table in the memory 110. For example, the correction table may be received through the interface provided separately to the battery cycle counting device 100 and then stored in the memory 110. The correction table indicates a correlation between predetermined battery parameters for the battery 10 and weights corresponding thereto, and may be prepared in the form of a look-up table. In some cases, the calibration table may already be stored at the time of manufacture of the battery 10 or the battery cycle counting device 100, in which case step S510 may be omitted.

In step S515, the measurement unit 120 of the battery cycle counting device 100 outputs battery information every predetermined period. Here, the battery information may include at least measurement values for each of the battery parameters. For example, the battery parameters may include the terminal voltage of the battery 10, charge / discharge current, temperature, charge / discharge time, and the like. Further, the battery information may include data (eg, SOC) calculated based on the measured value of each of the battery parameters.

In step S520, the calculator 130 of the battery cycle counting device 100 may calculate an additional amount of current indicating the degree to which the battery 10 has been used during the current period, based on the outputted battery information. The additional current amount may be an amount of current obtained by accumulating the charge / discharge current of the battery 10 from the start time to the end time of the current cycle.

In step S525, the correction unit 140 of the battery cycle counting apparatus 100 may obtain weights corresponding to at least some of the measurement values included in the battery information for the current period from the correction table.

In step S530, the correction unit 140 of the battery cycle counting apparatus 100 may correct the additional current amount using the obtained weights. Preferably, the correction unit 140 may correct the additional current amount by multiplying the obtained weights by an additional current amount.

In step S535, the updating unit 150 of the battery cycle counting device 100 updates the accumulated current amount indicating the degree to which the battery 10 has been used up to the current period, based on the corrected additional current amount. For example, the updater 150 may update the previous accumulated current amount by adding the additional current amount to the accumulated current amount up to the previous period.

In step S540, the counting unit 160 of the battery cycle counting device 100 may determine whether the increase amount of the accumulated current amount is greater than or equal to a predetermined reference current amount. That is, the counting unit 160 may compare a predetermined reference current amount with the updated cumulative current amount, and determine whether to increase the value of the cycle count of the battery 10 based on the result of the comparison. If it is determined that the increase amount of the accumulated current amount is equal to or greater than the predetermined reference current amount, step S545 is performed. If it is determined that the increase amount of the accumulated current amount is less than the predetermined reference current amount, the process may return to step S515.

In step S545, the counting unit 160 of the battery cycle counting device 100 may increase the value of the cycle count of the battery 10. For example, each time the updated cumulative current amount increases by the reference current amount, the value of the cycle count may be increased by one.

Although the present invention has been described above by way of limited examples and drawings, the present invention is not limited by this, and will be described below and the technical idea of the present invention by those skilled in the art to which the present invention pertains. Of course, various modifications and variations are possible within the equal scope of the claims.

Features described in individual embodiments herein may be implemented in combination in a single embodiment. Conversely, various features that are described in this specification in a single embodiment may be individually implemented in various embodiments, or may be implemented in appropriate subcombinations.

10: battery
100: battery cycle counting device
110: memory
111: first sub table
112: second sub table
113: third sub table
120: measuring unit
130: calculation unit
140: correction unit
150: update unit
160: counting unit

Claims (11)

A memory for storing a correction table indicating a correlation between predetermined battery parameters for a battery and corresponding weights;
A measurement unit coupled to the battery and outputting battery information including measurement values for each of the battery parameters every predetermined period;
A calculator configured to calculate an additional current amount indicating the degree of use of the battery during the current period based on the battery information;
A correction unit for obtaining weights corresponding to at least some of the measured values from the correction table and correcting the additional current amount using the obtained weights;
An updating unit updating the accumulated current amount indicating the degree of total use of the battery until the current period based on the corrected additional current amount; And
It includes; counting unit for determining whether to increase the value of the cycle count of the battery, based on the result of comparing the predetermined reference current amount and the updated cumulative current amount;
The predetermined battery parameters include SOC, current rate and temperature of the battery,
The correction table,
A first sub-table indicating a first correlation between a plurality of predetermined SOC periods and corresponding weights;
A second sub-table indicating a second correlation between a plurality of predetermined current rate periods and corresponding weights; And
And a third sub-table indicating a third correlation between a plurality of predetermined temperature intervals and weights corresponding thereto.
According to the first correlation, a relatively high SOC period among the plurality of SOC periods of the first sub-table corresponds to a relatively large weight among the weights of the first sub-table,
According to the second correlation, a relatively high current rate period among the plurality of current rate periods of the second sub table corresponds to a relatively large weight among the weights of the second sub table,
According to the third correlation, a temperature section relatively far from a predetermined suitable temperature section among the plurality of temperature sections of the third sub table corresponds to a relatively large weight among the weights of the third sub table. ,
The correction unit,
Obtain a first weight corresponding to the SOC section to which the measured SOC belongs, among a plurality of SOC sections of the first sub table, from the first sub table,
A second weight corresponding to a current rate period to which the measured current rate belongs among a plurality of current rate periods of the second sub table is obtained from the second sub table,
A third weight corresponding to a temperature section to which the measured temperature belongs among the plurality of temperature sections of the third sub table is obtained from the third sub table,
The calibrated additional current amount is a product of the first weight, the second weight, and the third weight and the additional current amount, a battery cycle counting device.
delete delete delete According to claim 1,
The counting unit,
The battery cycle counting device increases the value of the cycle count by a predetermined value whenever the updated cumulative current amount increases by the reference current amount. The battery cycle counting device according to any one of claims 1 and 5; And
And; at least one battery pack coupled to the battery cycle counting device. Storing a correction table indicating a correlation between predetermined battery parameters for the battery and corresponding weights;
Outputting battery information including measurement values for each of the battery parameters every predetermined period;
Calculating, based on the battery information, an additional amount of current indicating the degree to which the battery has been used during the current period;
Obtaining weights corresponding to at least some of the measured values from the correction table;
Correcting the additional amount of current using the obtained weights;
Updating, based on the corrected additional current amount, a cumulative current amount indicating the degree of total use of the battery until the current period; And
And determining whether to increase the value of the cycle count of the battery based on a result of comparing the predetermined reference current amount with the updated cumulative current amount.
The predetermined battery parameters include SOC, current rate and temperature of the battery,
The correction table,
A first sub-table indicating a first correlation between a plurality of predetermined SOC periods and corresponding weights;
A second sub-table indicating a second correlation between a plurality of predetermined current rate periods and corresponding weights; And
And a third sub-table indicating a third correlation between a plurality of predetermined temperature intervals and weights corresponding thereto.
According to the first correlation, a relatively high SOC period among the plurality of SOC periods of the first sub-table corresponds to a relatively large weight among the weights of the first sub-table,
According to the second correlation, a relatively high current rate period among the plurality of current rate periods of the second sub table corresponds to a relatively large weight among the weights of the second sub table,
According to the third correlation, a temperature section relatively far from a predetermined suitable temperature section among the plurality of temperature sections of the third sub table corresponds to a relatively large weight among the weights of the third sub table. ,
The step of obtaining the weights,
Obtaining a first weight corresponding to the SOC section to which the measured SOC belongs from among the plurality of SOC sections of the first sub-table from the first sub-table;
Obtaining a second weight corresponding to a current rate period to which the measured current rate belongs among a plurality of current rate periods of the second subtable from the second subtable; And
And obtaining a third weight corresponding to a temperature range to which the measured temperature belongs from among the plurality of temperature sections of the third sub table from the third sub table.
The corrected additional current amount is the product of the first weight, the second weight, and the third weight and the additional current amount, the battery cycle counting method. delete delete delete The method of claim 7,
Incrementing the value of the cycle count by a predetermined value each time the updated cumulative current amount increases by the reference current amount;
Further comprising, a battery cycle counting method.

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