TWI710780B - Battery control apparatus and method for detecting internal short of battery - Google Patents

Abstract

Disclosed are a battery control apparatus and a method for detecting an internal short of a battery, which may include: acquiring first charge state information related to a charge state of the battery; detecting a first reference time point when the first charge state information satisfies a reference condition; acquiring second charge state information related to the charge state of the battery; detecting a second reference time point when the second charge state information satisfies a reference condition; and detecting an internal short of the battery based on a difference between a charge amount from the first reference time point to the second reference time point and a discharge amount from the first reference time point to the second reference time point.

Description

Battery control device and method for detecting internal short circuit of battery law

An exemplary embodiment of the present invention relates to a battery control device and a method for detecting an internal short circuit of a battery.

[Cross reference of related applications]

This application claims the Korean Patent Application No. 10-2018-0094543 filed with the Korean Intellectual Property Office on August 13, 2018, and the Korean patent application filed with the Korean Intellectual Property Office on July 22, 2019 The priority and rights of No. 10-2019-0088298, the entire content of the Korean patent application is incorporated into this application for reference.

With the development of electrical technology and electronic technology, the use of small and light portable electronic products with various functions is rapidly increasing. Batteries are generally used as power supply components for the operation of portable electronic products, and rechargeable batteries that are rechargeable and reusable are mainly used.

Unlike the non-rechargeable primary battery, the rechargeable The battery is a rechargeable and dischargeable battery. Rechargeable batteries are used in portable small electronic components (for example, portable phones or laptops), or are widely used as power sources for driving power tools, motors, etc. . The internal components of the rechargeable battery may be formed of a positive electrode, a negative electrode, a separation film, an electrolyte, etc., and a case may be formed of a metal plate or a pouch.

Rechargeable batteries with high energy density may cause safety problems, such as thermal runaway, and specifically, the positive and negative electrodes inside the rechargeable battery are short-circuited, causing the rechargeable battery to overheat (overheated). ) Is a representative example. The internal short circuit is caused by the loss of the function of the isolation film, and examples of the loss of the function of the isolation film include deformation caused by external impact, metallic foreign substances contained in the manufacturing process, and formation of lithium or copper through electrochemical reactions. Dendritic crystals (dendrite).

In the prior art, technology has been developed to detect the internal short-circuit state of the rechargeable battery in advance and prevent the internal short-circuit. In the prior art solution, when the voltage of the rechargeable battery is extremely stable (no load or extremely low load), an inspection time of tens of minutes or longer is required. Therefore, there is a disadvantage that it is impossible to detect an internal short circuit that occurs in a state where the rechargeable battery is continuously charged or discharged.

The above information disclosed in this background technology section is only used to enhance the understanding of the background technology of the present invention, and therefore it may include the prior art that is not formed in the country for those with ordinary knowledge of the technology. News.

The present invention aims to provide a battery control device and a method for detecting an internal short circuit of a battery. The battery control device and the method for detecting an internal short circuit of the battery can effectively detect the internal short circuit of the battery to prevent the battery Heat dissipation caused by the internal short circuit.

An exemplary embodiment of the present invention provides a method for detecting an internal short circuit of a battery. The method may include: acquiring first state of charge information related to the state of charge of the battery; and detecting when the first state of charge information A first reference time point when a reference condition is satisfied; acquiring second state of charge information related to the state of charge of the battery; detecting a second reference time point when the second state of charge information satisfies the reference condition; and Based on the difference between the charge amount from the first reference time point to the second reference time point and the discharge amount from the first reference time point to the second reference time point to detect the battery Internal short circuit.

The detecting the internal short circuit may include determining that the internal short circuit occurs in the battery when the difference between the charged amount and the discharged amount is equal to or greater than a threshold value.

Each of the first state of charge information and the second state of charge information may include a state of charge (SOC) of the battery, and the reference condition may include a reference state of charge.

The reference condition may include a full charge condition. In an exemplary embodiment, each of the first state of charge information and the second state of charge information may respectively include a current value and a voltage value of the battery, and the reference condition may include Reference current value and reference voltage value. In addition, the detecting the first reference time point may include detecting when the current value of the battery included in the first state of charge information is equal to or less than the reference current value and the first state of charge The first reference time point when the voltage value of the battery included in the information is equal to or greater than the reference voltage value, and the detecting the second reference time point may include detecting when the second reference time point is The current value of the battery included in the state of charge information is equal to or less than the reference current value and the voltage value of the battery included in the second state of charge information is equal to or greater than the reference voltage Value at the second reference time point.

The method may further include: determining whether the first state of charge information and the second state of charge information are similar to each other within a predetermined range, wherein when the first state of charge information and the second state of charge information are When they are similar to each other within the predetermined range, the detection of the internal short circuit can be performed.

The method may further include: determining whether at least one of the charge amount and the discharge amount is equal to or greater than a predetermined value, wherein when at least one of the charge amount and the discharge amount is equal to or greater than the At a predetermined value, the detection of the internal short circuit can be performed.

The method may further include: determining whether a time interval between the first reference time point and the second reference time point is within a threshold range, wherein when the time interval is within the threshold range, The detection of the internal short circuit can be carried out.

The threshold range may be a maximum of 48 hours.

The method may further include: when the first reference time point is detected, accumulating the amount of charging current supplied from the charging element to the battery and the amount of discharge current supplied from the battery to the load; and when detecting When the second reference time point is reached, the charging amount and the discharging amount are calculated based on the accumulated charging current amount and the discharging current amount.

The method may further include: resetting the accumulated amount of charging current and the amount of discharge current after the calculating the amount of charge and the amount of discharge.

Another exemplary embodiment of the present invention provides a battery control device. The battery control device may include: a measurement unit configured to measure the voltage, current, and temperature of the battery; and a detector, based on the measurement The unit measures at least one of the voltage value, current value, and temperature value of the battery to obtain state-of-charge information related to the state of charge of the battery, and to detect a reference when the state-of-charge information satisfies a reference condition Time point; an accumulator, when the detector detects the first reference time point, accumulates the charge current and discharge current of the battery until the detector detects the second reference time point, and is based on The accumulated amount of charging current and the amount of discharging current are used to calculate the amount of charge and discharge of the battery; and an internal short-circuit detector based on the time from the first reference time point to the second reference time point The difference between the charged amount and the discharged amount from the first reference time point to the second reference time point is used to detect an internal short circuit of the battery.

When the difference between the charged amount and the discharged amount is equal to or greater than a threshold value, the internal short circuit detector may determine that the internal short circuit has occurred in the battery.

The state of charge information may include the state of charge of the battery, and the reference condition may include a reference state of charge.

The reference condition may include a full charge condition. In an exemplary embodiment, the charge state information may include a current value and a voltage value of the battery, and the reference condition may include a reference current value and a reference voltage value. In addition, when the current value of the battery is equal to or less than the reference current value and the voltage value of the battery is equal to or greater than the reference voltage value, the detector may detect the reference time point .

When the state of charge information of the battery at the first reference time point and the state of charge information of the battery at the second reference time point are similar to each other within a predetermined range, the internal short circuit The detector may detect the internal short circuit based on the difference between the charged amount and the discharged amount.

When at least one of the charge amount and the discharge amount is equal to or greater than a predetermined value, the internal short circuit detector may detect the internal short circuit based on the difference between the charge amount and the discharge amount Short circuit.

When the time interval between the first reference time point and the second reference time point is within a threshold range, the internal short circuit detector may be based on the difference between the charged amount and the discharged amount To detect the internal short circuit.

The threshold range may be a maximum of 48 hours.

According to the exemplary embodiment of the present invention, there is an effect that the internal short circuit of the battery can be effectively detected and the heat dissipation of the battery can be prevented.

1: Battery control device

10: battery

20: Measuring unit

30: detection unit

31: Detector

32: accumulator

33: Internal short circuit detector

40: control unit

B+, B-: terminal

C: charge/discharge

cc1, cc2, cc3: charge capacity

d1, d2: poor

dc1, dc2, dc3: discharge capacity

Ds: short circuit detection signal

I: current

I _short : short circuit current

p1, p2, p3: comparison period

R _B : internal resistance

R _s : short-circuit resistance

S: switch

S10, S11, S12, S13, S14, S15, S16, S17, S18, S19, S20: steps

t: time

T: temperature

t1, t2, t3, t4: reference time point

V: voltage

FIG. 1 is a block diagram showing the configuration of a battery control device according to an exemplary embodiment of the present invention.

FIG. 2 is an equivalent circuit (equivalent circuit) of a battery according to an exemplary embodiment of the present invention.

FIG. 3 is a graph showing how the charge amount and the discharge amount change according to the occurrence of an internal short circuit of the battery.

4 is a flowchart showing a method for detecting an internal short circuit of a battery of a battery control device according to an exemplary embodiment of the present invention.

Hereinafter, the battery control device according to an exemplary embodiment of the present invention will be explained in more detail with reference to FIGS. 1 and 2.

FIG. 1 is a block diagram showing the configuration of a battery control device according to an exemplary embodiment of the present invention, and FIG. 2 is an equivalent circuit of a battery according to an exemplary embodiment of the present invention.

1, a battery control device 1 according to an exemplary embodiment of the present invention may include a battery 10, a measurement unit 20, a detection unit 30, and a control unit 40, and may prevent battery heat by sensing an internal short circuit of the battery 10 Dissipate.

The battery 10, which is a rechargeable and dischargeable secondary battery, may be referred to as a cell.

2, the battery 10 may include two terminals B+ and B- and can be charged by an external charging element (not shown) through the two terminals B+ and B- or by an external load (not shown) (Shown) discharge. For ease of description, it is stated that the charging element is provided outside the battery control device 1, but the exemplary embodiment of the present invention is not limited to this.

As shown in FIG. 2, the battery 10 may include an internal resistance R _B, and R _B may be the internal resistance of a few milliohms (milliohms) to several hundred milli-ohms resistance value. When an internal short circuit occurs in the battery 10, the same effect as the effect that the switch S inside the battery 10 is electrically connected will be produced.

When the switch S is electrically connected, a short current I _short flows in the short-circuit resistance R _s , thereby causing the battery 10 to be discharged. In this case, the short-circuit resistance R _s may have a wide range of resistance values from several milliohms to several kiloohms (kΩ).

The battery 10 is charged by one or more charging methods among constant current (CC) charging, constant voltage (constant voltage, CV) charging, and constant current-constant voltage (CC-CV) charging; ) In charging, the battery is charged with a constant current from the initial stage to the completion stage of self-charging; in constant voltage (CV) charging, the battery is charged with a constant voltage from the initial stage to the completion stage of self-charging; at constant current-constant voltage ( In CC-CV) charging, the battery is charged at a constant current at the initial stage of charging and at a constant voltage at the completion stage of charging. Constant current charging is a charging method for supplying a constant current to the battery 10 and charging the battery 10 until the battery 10 reaches a predetermined set voltage. While performing constant current charging, the voltage of battery 10 can be The charging capacity increases together. In this specification, the amount of charge means the amount of electric charge or capacity (or capacity) supplied by a charging element (not shown) to the battery 10 to charge the battery 10, and it means the amount of charge or capacity (or capacity). The state of charge (SOC) of the charge level is different. In addition, the discharge amount refers to the amount of charge or capacitance supplied from the battery 10 to a load (not shown).

When the charging and discharging of the battery 10 are repeated under the same conditions, the time point of full charging of the battery 10 (that is, after the battery 10 is fully charged and then discharged, until the battery 10 is fully charged again) The charge capacity is slightly larger than the discharge capacity. This difference is attributed to various energy losses (including heat generation, self-discharge, etc.) of the battery 10 during the charging/discharging process.

When an internal short circuit occurs in the battery 10, a short circuit current I _{short is} generated as shown in FIG. 2, and this causes energy loss due to the short circuit resistance R _s in the battery. Therefore, when an internal short circuit occurs in the battery 10, the amount of charge (discharge) that the battery 10 can supply to the load (not shown) is compared with the amount of charge (charge) that the charging element (not shown) can supply to the battery 10. The amount) is significantly less than before the internal short circuit occurred. That is, in the battery 10 where the internal short circuit occurs, some of the charge amount (charge amount) supplied by the charging element for charging the battery 10 during charging is included in the short-circuit resistance R _s . The internal short-circuit path consumes; compared with the amount of charge supplied by the self-charging element, the amount of charge actually accumulated in the battery 10 is less than before the occurrence of the internal short-circuit. In addition, in the battery 10 where an internal short circuit occurs, energy is consumed by the internal short circuit path including the short circuit resistance R _s at the time of discharge, and therefore, the charge supplied from the battery 10 to the external load is compared with the amount of charge actually discharged from the battery 10 The amount is less than before the internal short circuit occurred.

With reference to such characteristics, the battery control device 1 according to the exemplary embodiment monitors the charge amount and discharge amount of the battery 10 to detect an internal short circuit of the battery 10. The detailed configuration of detecting the internal short circuit of the battery 10 by monitoring the charge and discharge of the battery 10 will be described below.

The measuring unit 20 continuously measures the voltage V, current I, and temperature T of the battery 10, and transmits the measured voltage value, current value, and temperature value to the detection unit 30. In this specification, the current I of the battery 10 represents the charging current supplied to the battery 10 from a charging element (not shown) or the discharging current supplied from the battery 10 to an external load (not shown).

The detection unit 30 includes a detector 31, an accumulator 32, and an internal short-circuit detector 33. The detection unit 30 monitors the charge and discharge of the battery 10 and detects the internal short-circuit of the battery 10, and generates a short-circuit detection signal Ds.

The detector 31 freely acquires the state of charge information related to the state of charge of the battery 10 from the temperature value, voltage value and current value of the battery 10 received by the measuring unit 20 when the battery 10 is being charged. Here, the state of charge information may include the temperature value, voltage value, and current value of the battery 10 measured by the measurement unit 20, or may include the SOC of the battery 10.

In addition, the detector 31 detects a point in time when the state of charge information of the battery 10 satisfies a predetermined reference condition (hereinafter referred to as a "reference point in time").

In the detector 31, the reference condition for detecting the reference time point may include a reference SOC. In this case, the detector 31 can detect the SOC of the battery 10 The time point when the predetermined reference SOC is reached is used as the reference time point. The reference SOC may be an SOC that becomes a reference for determining that the battery 10 is in a fully charged state, but exemplary embodiments are not limited to this, and therefore, the reference SOC may be set to be a reference SOC for determining a fully charged state Low or high value.

In the detector 31, the reference condition used to detect the reference time point as the fully charged condition of the battery 10 may include at least one condition for determining the fully charged state of the battery 10.

As an example, the reference condition may include a reference voltage value and a reference current value for determining the fully charged state of the battery 10. In this case, the detector 31 may detect the time point when the voltage value of the battery 10 is equal to or greater than the reference voltage value and the current value of the battery 10 is equal to or less than the reference current value as the reference time point. The full charge condition may include other conditions besides the reference voltage value and the reference current value, and this may vary according to the scheme of the battery control device 1 determining the fully charged state of the battery 10.

In the detector 31, the reference condition for detecting the reference time point may include a reference voltage value and a reference current value to determine a predetermined state other than the fully charged state of the battery 10. In this case, the reference voltage value and the reference current value may correspond to the voltage value and the current value that become a reference for determining whether the battery 10 reaches the predetermined state of charge before or after the battery 10 reaches the fully charged state. In this case, similar to the detection of the fully charged state, the detector 31 can detect the time point when the voltage value of the battery 10 is equal to or greater than the reference voltage value and the current value of the battery 10 is equal to or less than the reference current value as the reference time point.

The accumulator 32 accumulates the amount of charge and discharge of the battery 10 until the next reference time point is detected when the detector 31 detects the reference time point to calculate the time period between the two reference time points ( Hereinafter referred to as and used as the “comparison period”) the charge and discharge capacity of the battery 10. Here, the accumulator 32 can accumulate the amount of charging current supplied from the charging element to the battery 10 during the comparison period, acquire the amount of charge from the accumulated amount of charging current during the comparison period, and provide information on the amount of charging current supplied from the battery 10 during the comparison period. The discharge current amount to the external load is accumulated, and the discharge amount is obtained from the accumulated discharge current amount during the comparison period.

In this solution, the accumulator 32 may use two different reference time points as the start reference time point and the end reference time point to calculate the charging capacity and the discharging capacity of each of the multiple comparison periods. For this reason, when the reference time point is detected, the accumulator 32 is reset to reset the amount of charge current and the amount of discharge current accumulated during the previous comparison period and to newly start the accumulation of the amount of charge current and discharge current. . The start reference time point of each comparison period may be the same as the end reference time point of the previous comparison period, and the end reference time point may be the same as the start reference time point of the next comparison period.

The accumulator 32 may be a single accumulator with a symbol, and may include two accumulators to respectively accumulate the amount of charging current and the amount of discharging current, but the exemplary embodiment is not limited to this.

When the accumulator 32 calculates the amount of charge and discharge during each comparison period, the internal short circuit detector 33 detects the internal short circuit of the battery 10 based on the calculated amount of charge and discharge, and will include information about whether an internal short occurs. Test news The number Ds is transmitted to the control unit 40.

The control unit 40 can control the connection or disconnection of an external charging device (not shown) or a load (not shown) connected to the battery 10 based on the detection signal Ds received from the internal short circuit detector 33. For example, when the internal short circuit detector 33 generates the detection signal Ds indicating the occurrence of the internal short circuit of the battery 10, the control unit 40 can interrupt the external charging device (not shown) or the load (not shown) connected to the battery 10 Connection.

Therefore, the battery control device 1 can detect the internal short circuit of the battery 10 and control the connection between the battery 10 and the charging device (or load) based on the detection result of the internal short circuit, thereby preventing the battery 10 from heating due to the internal short circuit. Dissipate.

As described above, when the internal short circuit of the battery 10 is detected by comparing the charge amount and the discharge amount of the battery 10 during the comparison period with the start reference time point and the end reference time point, at the start reference time point of the comparison period The amount of charge (or SOC) held by the battery 10 at the location and the amount of charge (or SOC) held by the battery 10 at the end reference time point need to be equal to each other or similar to each other at a predetermined level or higher. This is because the difference between the amount of charge held by the battery 10 at the start reference time point of the comparison period and the amount of charge held by the battery 10 at the end reference time point of the comparison period, in addition to the internal short circuit The difference between the charged capacity and the discharged capacity of the battery 10 during the comparison period is affected, and therefore it is difficult to detect the internal short circuit by comparing the charged capacity and the discharged capacity.

Therefore, the battery control device 1 sets the reference condition to detect that when the state of charge of the battery 10 reaches the amount of charge held by the battery 10, it is determined to have a period of time compared with The time when the start reference time point and the end reference time point coincide with a predetermined value state (for example, a fully charged state).

In addition, when the internal short circuit detector 33 determines that the state of charge of the battery 10 at the start reference time point of a comparison period and the state of charge of the battery 10 at the end reference time point are at a predetermined level or due to changes in the surrounding environment of the battery 10 When higher levels are different from each other, the internal short circuit detector 33 can omit the detection of the internal short circuit. For example, when the full charge condition used to determine the full charge state of the battery 10 is set to change according to changes in the surrounding environment (such as temperature, etc.), the full charge condition at the start reference time point of a comparison period and the end The full charge conditions at the reference time point may be different from each other. Therefore, the internal short circuit detector 33 compares the charge state information (for example, voltage value, current value, temperature value, etc.) of the battery 10 at the start reference time point of the comparison period with the charge state information at the end reference time point (for example, Voltage value, current value, temperature value, etc.) are compared with each other to determine whether an internal short circuit is detected.

In addition, the internal short circuit detector 33 may detect the internal short by comparing the charged amount and the discharged amount only when at least one of the charged amount and the discharged amount generated during the comparison period is equal to or greater than a predetermined value. This is because if the charging and discharging amounts during the comparison period are too small, the difference between the charging and discharging due to the internal short circuit is not significant, and the reliability of the internal short circuit detection will be reduced.

In addition, the internal short circuit detector 33 only works when the length of the comparison period (that is, the time interval between the start reference time point and the end reference time point of the comparison period) When within a predetermined threshold range, the charge and discharge are compared with each other to detect internal short circuits. This is to prevent the detection reliability from being reduced due to the detection of an internal short circuit in the following cases: the time interval between the start reference time point and the end reference time point is too short, so that the internal short circuit caused the charge and discharge capacity The difference between the two is not significant, or the time interval between the start reference time point and the end reference time point is so long that the information of the accumulator 32 may be unreliable. Therefore, the internal short circuit detector 33 sets the threshold range so that the minimum time for the difference between the charge and discharge due to the internal short circuit to reach a detectable level is set to the minimum value, and it will be used to secure the accumulator 32 The maximum time for the reliability to reach a predetermined level or higher is set to the maximum value, and only when the length of the comparison period (the time interval between the start reference time point and the end reference time point) is within the threshold range The charge and discharge are compared to compare the charge and discharge to detect internal short circuits. The threshold range can be set to a minimum of 2 hours and a maximum of 48 hours, but the exemplary embodiment is not limited to this.

Hereinafter, a method for detecting the internal short circuit of the battery 10 by the battery control device 1 will be explained with reference to FIG. 3.

FIG. 3 is a graph schematically showing the change in the amount of charge and discharge according to the occurrence of an internal short circuit of the battery 10, and shows that the battery 10 is repeatedly charged and discharged by the CC-CV charging method and the CC discharging method The situation serves as an example.

In the graph of FIG. 3, t represents time, I represents the charging current supplied from the charging element to the battery 10 or the discharging current supplied from the battery 10 to the load, and C represents the amount of charge or discharge. 3, while the charging current is supplied to the battery 10, the charging capacity of the battery 10 continuously increases, and the discharge current is supplied from the battery 10 At this time, the discharge capacity of the battery 10 continuously increases.

In FIG. 3, as an example, the detector 31 uses the information obtained by the measurement unit 20 to obtain information about the state of charge of the battery 10, and detects multiple times when the state of charge information of the battery 10 satisfies the fully charged condition. Points are used as reference time points t1, t2, t3, and t4. In addition, whenever the reference time points t1, t2, t3, and t4 are detected, the detector 31 stores the information about the charging state of the battery 10 at the corresponding time points in a memory (not shown).

When the reference time points t1, t2, t3, and t4 are detected, the accumulator 32 sets each of the reference time points t1, t2, t3, and t4 as the start reference time point or the end reference time point for multiple comparisons. Periods p1, p2, and p3 are used to calculate the charge amounts cc1, cc2, and cc3 and the discharge amounts dc1, dc2, and dc3. The accumulator 32 can calculate the charge during each of the comparison periods p1, p2, and p3 by accumulating the amount of charging current and the amount of discharge current in each of the plurality of comparison periods p1, p2, and p3. Quantity and discharge capacity.

Specifically, when the reference time point t1 is detected, the accumulator 32 then accumulates each of the charging current amount and the discharging current amount until the reference time point t2 is detected. In addition, when the reference time point t2 is detected, the charging amount cc1 and the discharging amount dc1 of the comparison period p1 are calculated based on the amount of charging current and the amount of discharge current accumulated from the reference time point t1 to the reference time point t2. In addition, the amount of charge current and the amount of discharge current accumulated so far are reset, and then the amount of charge current and the amount of discharge current are respectively accumulated until the reference time point t3 is detected after the start of the new accumulation.

In addition, when the reference time point t3 is detected, the charge amount cc2 and the discharge amount dc2 of the comparison period p2 are calculated based on the amount of charging current and the amount of discharge current accumulated from the reference time point t2 to the reference time point t3. In addition, the amount of charging current and the amount of discharge current accumulated so far are reset, and then the amount of charging current and the amount of discharging current are respectively accumulated until the reference time point t4 is detected after the start of the new accumulation.

In addition, when the reference time point t4 is detected, the charging amount cc3 and the discharging amount dc3 of the comparison period p3 are calculated based on the amount of charge current and the amount of discharge current accumulated from the reference time point t3 to the reference time point t4.

In this scheme, the internal short circuit detector 33 compares the calculated charge and discharge amount each time the charge amount and the discharge amount in each of the comparison periods p1, p2, and p3 are calculated, and when the charge amount When the difference with the discharge amount is equal to or greater than the threshold, it is determined that an internal short circuit has occurred. In addition to the internal short circuit, while charging/discharging of the battery 10 is in progress, the energy of the battery 10 may be lost due to heat generation or the like. However, the amount of energy lost in this case is insignificant and can be ignored by appropriately setting the threshold value when detecting an internal short circuit. That is, the battery control device 1 sets the threshold value for internal short-circuit detection to a predetermined value or greater, and then determines that the energy loss is caused by factors other than the internal short-circuit.

Taking FIG. 3 as an example, the comparison period p1 is the period before the internal short circuit occurs, and the charge and discharge amounts during the comparison period p1 are very similar to each other.

Thereafter, an internal short circuit occurs during the charging of the battery 10 in the comparison period p2, thereby making the charge amount cc2 in the comparison period p2 greater than that of the battery 10 The charge amount cc1 in the comparison period p1 in the normal state. Therefore, the difference d1 between the discharge amount dc2 and the charge amount cc2 during the comparison period p2 becomes equal to or greater than the threshold value, and the internal short circuit detector 33 can detect the internal short circuit of the battery 10.

Thereafter, in the comparison period p3, charging and discharging are performed in a state where an internal short-circuit occurs, thereby further increasing the energy loss due to the internal short-circuit. Therefore, the difference d2 between the discharged amount dc3 and the charged amount cc3 during the comparison period p3 increases compared to the difference d1 during the previous comparison period p2. Therefore, the internal short circuit detector 33 detects the internal short circuit of the battery 10 again.

In the above-mentioned battery control device 1, the measurement unit 20, the detection unit 30, or the control unit 40 can be implemented by one or more central processing units (CPU) or processors implemented by other chipsets, microprocessors, etc. Implement.

Hereinafter, a battery control method according to an exemplary embodiment of the present invention will be explained with reference to FIG. 4.

FIG. 4 is a flowchart illustrating a method for detecting an internal short circuit according to an exemplary embodiment of the present invention.

The method for detecting the internal short circuit in FIG. 4 can be implemented by the battery control device 1 described with reference to FIGS. 1 and 2.

4, the detection unit 30 obtains the charge state information of the battery 10 (S10), and compares the charge state information with the reference condition to determine whether the reference time point when the charge state information of the battery 10 meets the reference condition is detected (S11) .

In step S10, the detection unit 30 receives the measurement results of the voltage, current, and temperature of the battery 10 from the measurement unit 20, and the self-measurement results are Charge state information related to the charge state of the battery 10. Here, the state of charge information may include the temperature value, voltage value, and current value of the battery 10 measured by the measurement unit 20, or may include the SOC of the battery 10.

In step S11, the reference time point is used as the start time point or the end time point of the comparison period, and the reference condition for detecting the reference time point may include a reference SOC, a full charge condition, or a reference voltage value and a reference current value.

The detection unit 30 repeatedly executes the step S10 of acquiring the charge state information of the battery 10 until the reference time point is detected, and executes the step S11 of judging whether the reference time point is detected by comparing the charge state information with the reference condition. In addition, when the reference time point is detected by step S11, the detection unit 30 accumulates the amount of charging current supplied from the charging element to the battery 10 and the amount of discharge current supplied from the battery 10 to the load (S12). In addition, the detection unit 30 obtains the charge state information of the battery 10 (S13), and determines whether the reference time when the charge state information of the battery 10 meets the reference condition is detected by comparing the obtained charge state information with the reference condition Click (S14).

The detection unit 30 repeatedly executes the step S12 of accumulating the amount of charging current and the amount of discharge current until the reference time point is detected, executes the step S13 of acquiring the state of charge information of the battery 10, and executes the step S13 of acquiring the state of charge information of the battery 10, and executes Step S14 of comparing to determine whether the reference time point is detected. In addition, when the reference time point is detected in step S14, the charge and discharge currents accumulated so far are used to calculate the charge and discharge of the battery 10 (S15). In addition, by resetting the accumulator 32, the amount of charging current accumulated so far and the release The electric current is reset (S16).

In step S15, the amount of charging current and the amount of discharging current accumulated from the reference time point detected in step S11 to the reference time point detected in step S14 are used to calculate the amount of charge and discharge. That is, in this case, in the comparison period for calculating the charged amount and the discharged amount, the start time point may become the reference time point detected by step S11, and the end time point may become the reference time point detected by step S14 Reference time point.

On the other hand, before detecting the internal short circuit of the battery 10 by comparing the charge amount and the discharge amount in the comparison period, the detection unit 30 first checks whether the current situation is a state where internal short circuit detection can be performed to ensure detection reliability (S17). In addition, if it is determined that the current situation is a state where internal short-circuit detection can be performed, the charge amount and the discharge amount in the comparison period are compared, and the process proceeds to step S18 to implement internal short-circuit detection.

For example, in step S17, the detection unit 30 checks the state of charge information (for example, voltage value, current value, temperature value, etc.) of the battery 10 when the reference time point is detected in step S11 and the reference time in step S14 Whether the charge state information (for example, voltage value, current value, temperature value, etc.) of the battery 10 at a point is similar to each other at a predetermined level or higher, and if the two charge state information are at a predetermined level or higher Similarly, the process can proceed to step S18. Specifically, when the difference between the temperature value of the battery 10 at the reference time point detected by step S11 and the temperature value of the battery 10 at the reference time point detected by step S14 is equal to or less than a predetermined value , The battery at the reference time point detected by step S11 The difference between the current value of 10 and the current value of the battery 10 at the reference time point detected by step S14 is equal to or less than a predetermined value, and the difference between the current value of the battery 10 at the reference time point detected by step S11 When the difference between the voltage value and the voltage value of the battery 10 at the reference time point detected by step S14 is equal to or less than a predetermined value, the detection unit 30 may determine the battery 10 at the two reference time points. The charging status information is similar.

In addition, for example, in step S17, the detection unit 30 may check whether at least one of the charged capacity and the discharged capacity from the reference time point detected in step S11 to the reference time point detected in step S14 It is equal to or greater than a predetermined value, and when at least one of the charge amount and the discharge amount is equal to or greater than the predetermined value, the process may proceed to step S18.

In addition, for example, in step S17, the detection unit 30 may set the reference time point detected by step S11 as the start time point and the reference time point detected by step S14 as the end time point. The length of the comparison period is compared with a threshold range (for example, from a minimum of 2 hours to a maximum of 48 hours), and if the length of the comparison period is within the threshold range, the process can proceed to step S18.

In step S17, if all the conditions listed above as an example are met, the detection unit 30 may proceed to step S18 to perform internal short-circuit detection by comparing the charge amount and the discharge amount in the comparison period. However, since the exemplary embodiment is not limited to this, even if only some of the conditions listed above as examples are satisfied, the detection unit 30 may proceed to step S18 to compare the charge and discharge in the period of time. The quantity is compared to implement internal short circuit detection.

The above step S17 is to prevent the difference between the charge and discharge calculated during the comparison period from increasing to a threshold value or greater due to factors other than the internal short Internal short-circuit detection is performed when the difference between the charge and discharge caused by an internal short circuit does not reach a detectable level, or to prevent internal short-circuit detection when the reliability of the calculated charge and discharge is low .

When it is determined by step S17 that the current situation is not a situation that enables internal short-circuit detection, the detection unit 30 proceeds to step S12 to start the accumulation of the charge current amount and the discharge current amount in the new comparison period. In this case, the reference time point previously detected by step S14 becomes the start time point of the new comparison period, and the reference time point detected later becomes the end time point of the new comparison period.

If it is determined in step S17 that the current situation is capable of internal short-circuit detection, the detection unit 30 determines the amount of charge and discharge from the reference time point detected in step S11 to the reference time point detected in step S14 Whether the difference between is equal to or greater than the threshold value (S18). In addition, when the difference between the charged capacity and the discharged capacity is equal to or greater than the threshold, it is determined that an internal short circuit has occurred in the battery 10 (S19), and the battery 10 and the charging element (not shown) or the battery 10 and The load is connected (S20) to prevent the heat of the battery 10 from escaping.

Meanwhile, in this specification, it is explained as an example that the battery control device 1 detects an internal short circuit of one battery 10, but the exemplary embodiment is not limited to this. For example, the battery control device 1 can detect each battery by applying the internal short-circuit detection method to even a battery module in which multiple batteries are arranged in series and/or in parallel. The internal short circuit of a battery. In this case, the voltage value of the battery 10 can correspond to the voltages of the terminals B+ and B- of the battery 10, and the current value of the battery 10 can correspond to the charging current supplied to the battery module by the self-charging element or from the battery. The discharge current supplied by the module to the load corresponds.

Although the present invention has been described in conjunction with exemplary embodiments that are currently considered to be actual, it should be understood that the present invention is not limited to the disclosed embodiments. On the contrary, the present invention is intended to cover various modifications and equivalent arrangements included in the spirit and scope of the appended patents.

S10, S11, S12, S13, S14, S15, S16, S17, S18, S19, S20: steps

Claims (18)

A method for detecting an internal short circuit of a battery, the method comprising: acquiring first state of charge information related to the state of charge of the battery; detecting a first reference time when the first state of charge information satisfies a reference condition Point; acquiring second state-of-charge information related to the state of charge of the battery; detecting a second reference time point when the second state-of-charge information satisfies the reference condition; and based on the first reference The difference between the charge amount from the time point to the second reference time point and the discharge amount from the first reference time point to the second reference time point is used to detect the internal short circuit of the battery. The method according to claim 1, wherein: the detecting the internal short circuit includes determining the battery when the difference between the charged capacity and the discharged capacity is equal to or greater than a threshold value The internal short circuit occurred in the. The method according to claim 1, wherein: each of the first state of charge information and the second state of charge information includes the state of charge of the battery, and the reference condition includes a reference charge status. The method described in item 1 of the scope of patent application, wherein: the reference condition includes a fully charged condition. The method described in item 1 of the scope of patent application, wherein: Each of the first state of charge information and the second state of charge information includes a current value and a voltage value of the battery, the reference condition includes a reference current value and a reference voltage value, and the detecting The first reference time point includes detecting when the current value of the battery included in the first state of charge information is equal to or less than the reference current value and the battery included in the first state of charge information The first reference time point when the voltage value is equal to or greater than the reference voltage value, and the detecting the second reference time point includes detecting when the second charge state information includes the The second reference time when the current value of the battery is equal to or less than the reference current value and the voltage value of the battery included in the second state of charge information is equal to or greater than the reference voltage value point. The method described in item 1 of the scope of patent application further includes: determining whether the first state of charge information and the second state of charge information are similar to each other within a predetermined range, wherein when the first state of charge information is When the second state of charge information is similar to each other within the predetermined range, the detection of the internal short circuit is performed. The method described in item 1 of the scope of patent application further includes: judging whether at least one of the charging capacity and the discharging capacity is equal to or greater than a predetermined value, wherein when the charging capacity and the discharging capacity are When at least one of them is equal to or greater than the predetermined value, the detection of the internal short circuit is performed. The method described in item 1 of the scope of patent application further includes: Determine whether the time interval between the first reference time point and the second reference time point is within a threshold range, wherein when the time interval is within the threshold range, the internal short circuit is executed The detection. The method as described in item 1 of the scope of patent application further includes: when the first reference time point is detected, the amount of charging current supplied from the charging element to the battery and the discharge from the battery supplied to the load The amount of current is accumulated; and when the second reference time point is detected, the amount of charge and the amount of discharge are calculated based on the accumulated amount of charging current and the amount of discharge current. The method described in item 9 of the scope of patent application further includes: resetting the accumulated charging current amount and the discharging current amount after the calculation of the charging amount and the discharging amount. A battery control device, comprising: a measuring unit configured to measure the voltage, current and temperature of the battery; a detector based on the voltage value, current value and temperature value of the battery measured by the measuring unit At least one of to obtain state-of-charge information related to the state of charge of the battery, and to detect a reference time point when the state-of-charge information meets a reference condition; an accumulator, when the detector detects a first reference At the time point, the charge current amount and the discharge current amount of the battery are accumulated until the detector detects the second reference time point, and based on the accumulated charge current amount and the discharge current amount The amount of current is used to calculate the amount of charge and discharge of the battery, wherein the first state of charge information at the first reference time point and the second state of charge information at the second reference time point both satisfy the reference condition And an internal short circuit detector, based on the amount of charge from the first reference time point to the second reference time point and the discharge from the first reference time point to the second reference time point To detect the internal short circuit of the battery. The device according to item 11 of the scope of patent application, wherein: when the difference between the charged capacity and the discharged capacity is equal to or greater than a threshold value, the internal short circuit detector determines that the battery is The internal short circuit. The device according to claim 11, wherein: the state of charge information includes the state of charge of the battery, and the reference condition includes a reference state of charge. The device described in item 11 of the scope of patent application, wherein: the reference condition includes a fully charged condition. The device according to claim 11, wherein: the state of charge information includes the current value and the voltage value of the battery, the reference condition includes the reference current value and the reference voltage value, and when the battery is When the current value is equal to or less than the reference current value and the voltage value of the battery is equal to or greater than the reference voltage value, the detector detects the reference time point. The device according to item 12 of the scope of patent application, wherein: when the charge state information of the battery at the first reference time point is When the state of charge information of the battery at the second reference time point is similar to each other within a predetermined range, the internal short circuit detector detects based on the difference between the charged amount and the discharged amount The internal short circuit. The device according to claim 11, wherein: when at least one of the charged amount and the discharged amount is equal to or greater than a predetermined value, the internal short circuit detector is based on the charged amount and the The difference between the discharge amounts is used to detect the internal short circuit. The device according to claim 11, wherein: when the time interval between the first reference time point and the second reference time point is within a threshold range, the internal short circuit detector is based on the The difference between the charged amount and the discharged amount is used to detect the internal short circuit.

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