TW201716793A - Degradation degree detection method of lead battery and charging control method of lead battery detect degradation degree based upon information obtained in charging so as to prevent error from accumulating - Google Patents

Abstract

The purpose of the invention is to provide a degradation degree detection method and charging control method to prevent detection error of degradation degree of lead battery from accumulating. The method of the invention comprises the following steps: detecting a first time at which voltage or current achieves predetermined threshold value during ongoing charging by way of first charging, detecting a second time achieving the predetermined charging state during ongoing charging by way of first charging or second charging after first time, detecting degradation degree based upon elapsed time between the first time and the second time, based upon degradation degree and times of common charging process implemented after finally implementing balanced charging process, deciding to implement common charging process or to implement balanced charging process during next charging.

Description

Method for detecting deterioration degree of lead battery and charging control method for lead battery

The present invention relates to a lead battery, and more particularly to the detection of the degree of deterioration and the control of charging.

As the deterioration of the battery occurs, the characteristics of the lead battery also change. Therefore, detecting the degree of deterioration contributes to high-precision control. For example, Patent Document 1 listed below discloses a technique of controlling a lead battery using a deterioration count value associated with the degree of deterioration, and specifically, switching between normal charging and equalizing charging according to the degree of deterioration.

[Previous Technical Literature] [Patent Literature]

Patent Document 1: Japanese Laid-Open Patent Publication No. 2010-112853

However, in the prior art, there is a problem that the detection error of the degree of deterioration is accumulated. For example, in the method of Patent Document 1, the deterioration count value is only accumulated and does not reset. Therefore, when an error occurs between the actual deterioration degree and the deterioration count value, the error is accumulated. As a result, the detection error of the degree of deterioration becomes large.

The error in the degree of deterioration may cause various problems, and an example thereof will be described in accordance with Patent Document 1. If the deterioration count value is larger than the actual deterioration degree, the frequency of the equalization charging will increase unnecessarily, causing the liquid temperature to rise and the deterioration to be intensified. Further, if the deterioration count value is smaller than the actual deterioration degree, the frequency of the equalization charging may be insufficient, resulting in insufficient charging, and for example, the difference between the battery cells may not be sufficiently eliminated.

The present invention has been made in order to solve the above problems, and an object of the present invention is to provide a deterioration degree detecting method and a charging control method for preventing accumulation of a detection error of a deterioration degree of a lead battery.

The method for detecting deterioration degree of a lead battery according to the present invention includes the step of detecting a first time point when a voltage or a current reaches a predetermined threshold value during charging by the first charging method; after the first time point a step of detecting a second time point of reaching a predetermined state of charge during charging by the first charging method or charging by a second charging method different from the first charging method; and according to the first time point The elapsed time between the second time points, the amount of change in the amount of charge, or the amount of change in the charge rate, the step of detecting the degree of deterioration.

According to the above configuration, the degree of deterioration is detected based on the amount of change (i.e., time) between the first time point and the second time point during charging, the amount of change in the amount of charge, or the amount of change in the charge rate.

Alternatively, the degree of deterioration may be detected based on the elapsed time.

Further, the method for detecting deterioration degree of a lead battery according to the present invention includes the steps of: detecting a first time point when a voltage or a current reaches a predetermined threshold value during charging; and charging according to the first time point The amount or rate of charge, the step of detecting the degree of deterioration.

According to the above configuration, the degree of deterioration is detected based on the amount of charge or the charging rate at the first time point during charging.

Alternatively, the degree of deterioration is detected based only on information related to the previous charging process.

Further, the charge control method of the lead battery of the present invention selectively uses a normal charge process and an equalization charge process, and has the following steps: a step of detecting the degree of deterioration by the above method; and a balance according to the degree of deterioration and the last implementation. The number of ordinary charging processes performed after the charging process determines the step of performing a normal charging process or performing a balanced charging process at the next charging.

According to the present invention, the degree of deterioration is detected based on the information acquired during charging, so that the accumulation of errors can be avoided.

Ith‧‧‧ current threshold (predetermined threshold)

Vth‧‧‧ voltage threshold (predetermined threshold)

T11 to t13‧‧‧ (1st hour)

Time t14‧‧‧ (2 o'clock)

T1a, T1b, T1c‧‧‧ time difference (time)

T21, t22‧‧‧ time (1st hour)

T23, t24‧‧‧ time (2 o'clock)

T2a, T2b‧‧‧ time difference (time)

Time t31‧‧‧ (1st hour)

Time t33‧‧‧ (2 o'clock)

T3‧‧‧ time difference (time)

Time t41‧‧‧ (1st hour)

Time t42‧‧‧ (2 o'clock)

T4‧‧‧ time difference (after time)

Time t51‧‧‧ (1st hour)

Time t52‧‧‧ (1st hour)

Time t53‧‧‧ (2 o'clock)

T54‧‧‧ Time (2 o'clock)

T5a, T5b‧‧‧ time difference (time)

E61 to e63‧‧‧Charging capacity (1st hour)

E64‧‧‧Charging capacity (2nd hour)

E6a, E6b, E6c‧‧‧Changes in charge

Fig. 1 is a view showing the configuration of a lead-containing battery according to Embodiment 1 of the present invention.

Fig. 2 is a graph showing an embodiment of the method of the first embodiment.

Fig. 3 is a graph showing an example of a method of calculating the deterioration count value.

Fig. 4 is a graph showing an embodiment of the method of the second embodiment.

Fig. 5 is a graph showing an embodiment of the method of the third embodiment.

Fig. 6 is a graph showing an embodiment of the method of the fourth embodiment.

Fig. 7 is a graph showing an embodiment of the method of the fourth embodiment.

Fig. 8 is a graph showing an embodiment of the method of the fifth embodiment.

Hereinafter, embodiments of the present invention will be described based on the drawings.

Embodiment 1.

Fig. 1 is a view showing the configuration of a lead-containing battery according to Embodiment 1 of the present invention. The lead battery is charged by being connected to a generator to receive power supply, and is supplied with electric power by discharging by being connected to a load. A lead battery system can also have a plurality of battery cells. The lead battery is, for example, an open type lead battery, but may be a sealed lead battery, and is a liquid lead battery, but is not limited to a liquid type.

A control device for controlling the charge and discharge operation of the lead battery in the lead battery connection. The control device is constituted by, for example, a computer, and includes a computing means such as a microprocessor and a memory means such as a semiconductor memory. The control device implements the method of the present invention by executing a program stored in a memory means.

The control device is capable of measuring, calculating, or obtaining at least one of time, voltage between terminals of the lead battery, and current flowing through the lead battery. Further, the control device can measure, calculate, or obtain the charge rate of the lead battery, the charge and discharge power of the lead battery, the charge and discharge amount of the lead battery, and the charge rate of the lead battery. In the present specification, the "charge amount" may refer to the amount of power to be charged, and the "discharge amount" may refer to the amount of power discharged.

The lead battery is mounted on a vehicle, for example. At this time, the generator system may be a motor generator, and the load system may include an auxiliary machine. Device.

Fig. 2 is a graph showing an embodiment of the method of the embodiment. This graph schematically shows the relationship between the elapsed time and the voltage (voltage between terminals) in the charging process of the constant current mode of the lead battery. The curve 11 is a curve of a lead battery of a new product (small degree of deterioration), and the curve 12 is a curve of a lead battery in a state in which the new product is deteriorated (in the degree of deterioration), and the curve 13 is a state in which the deterioration is more (the degree of deterioration is large). The curve of the lead battery. No matter which curve is the curve of the charging process after discharging the same amount of power.

In the lead battery (curve 11) having a small degree of deterioration, the voltage does not reach the predetermined voltage threshold value Vth at the start of charging, and as the charging progresses, the voltage rises and reaches Vth at time t13 (first time point). The control device detects the first time point. After the first time, the charging is continued, and the charging rate reaches 100% at time t14 (second time point). The control device detects the second time point. The time difference between the first time point and the second time point (which can also be referred to as elapsed time. The same applies hereinafter) is t14-t13=T1a.

The charging rate of 100% is, for example, a state in which the charging amount is the same as the amount of discharge of the previous discharging operation. At this time, the control device can calculate the charging rate by measuring the amount of discharge and the amount of charge. In addition, the charging rate is 100%, and it can also be detected by the method described in JP-A-2015-12653, and it can also be detected by another method.

In general, in a lead battery, the internal resistance rises as the deterioration of the battery increases, so that the voltage is advanced to Vth. For example, in the lead battery (curve 12) in the degree of deterioration, Vth is reached at time t12 (first time point) earlier than time t13. The time difference between the first time point and the second time point T14-t12=T1b (where T1b>T1a). Further, in the lead battery (curve 13) having a large degree of deterioration, Vth is reached at time t11 (first time point) earlier than time t12. The time difference between the first time point and the second time point is t14-t11=T1c (where T1c>T1b). As described above, as the deterioration of the lead battery is intensified, the time difference between the first time point and the second time point becomes large. From the above principle, it can be said that the time difference is related to the degree of deterioration of the lead battery.

The control device detects the degree of deterioration based on the elapsed time (T1a, T1b, T1c) between the first time point and the second time point. The elapsed time can be calculated, for example, by subtracting the time of the first time point from the time of the second time point. As a specific method of determining the degree of deterioration, for example, the value of the elapsed time can be directly used as the degree of deterioration, or the degree of deterioration can be calculated as a value including a function of elapsed time (for example, compensation based on temperature).

As described above, according to the first embodiment of the present invention, the degree of deterioration is detected based on information (time, voltage, charging rate, and the like) acquired during charging. In particular, in the illustrated embodiment, the degree of degradation is detected based only on information related to the previous (latest or last) charging process. Therefore, the degree of deterioration can be independently detected for each charging operation, and the error of the degree of deterioration of the previous charging operation is not accumulated.

The degree of deterioration detected can be used for various purposes, and an example of the use of the embodiment will be described below.

In the case of the charging control method of the lead battery, the control device utilizes the degree of deterioration when selectively using the normal charging process and the equalizing charging process. The normal charging process is, for example, a process in which the amount of charge is 115% of the amount of discharge; the so-called equalization charging process is For example, a process of charging more than the normal charge (for example, an increase of only 10%) is performed.

In the present embodiment, the control device memorizes the charge count value indicating the number of times of normal charge processing that has been continuously performed at the current point. For example, when the discharge, normal charging, discharging, equalizing charging, discharging, normal charging, discharging, normal charging, discharging, normal charging, and discharging operations are performed so far, the charging count value is 3. In other words, the charge count value represents the number of ordinary charge processes performed after the last implemented equalization charge process.

The control device determines whether to perform normal charging processing or perform equalization charging processing at the next charging based on the degree of deterioration detected as described above and the charging count value. For example, the deterioration count value is calculated based on the degree of deterioration, and a value including a predetermined determination function of the deterioration count value and the charge count value is calculated, and if the value of the determination function is equal to or greater than a predetermined threshold, it is determined to perform equalization charging. Processing, if otherwise decided to implement normal charging processing. The predetermined determination function is, for example, a sum of the deterioration count value and the charge count value, but may be a linear function including a weighted sum, may also contain two or more items, and may contain variables or constants other than the above.

Fig. 3 is a graph showing an example of a method of calculating the deterioration count value. The graph can be said to map a degree of deterioration using a real value (or a continuous value) to a generalized monotonically increasing function of a deterioration count value using an integer value (or a discrete value). That is, when the degree of deterioration is small, the degree of deterioration is small, and the sum of the charge count values is also small, so the frequency of the equalization charging process is relatively low; and the greater the degree of deterioration, the larger the deterioration count value, and the sum of the charge count values is also It becomes larger, so the frequency of equalization charging processing increases. plus. The form of the function that specifically expresses the graph of Fig. 3 can be appropriately designed according to experiments and the like by those skilled in the art.

As described above, according to the first embodiment of the present invention, the frequency of the equalization charging process can be appropriately maintained. Therefore, it is possible to reduce the frequency of the equalization charging while suppressing the increase in the liquid temperature, and it is possible to reduce the shortage of charging and the variation between the battery cells.

In addition, compared with the control method of the prior art, since there is no continuous, cumulative parameter that is not reset during equalization charging, even if an error occurs, it does not accumulate and expand, and thus the error The impact is relatively small.

Further, in the first embodiment, since the degree of deterioration is detected based on the elapsed time between the first time point and the second time point, the degree of deterioration can be accurately detected without depending on the amount of discharge. That is, when the discharge amount is small, both the first time point and the second time point are reached from the start of charging for a short period of time. When the discharge amount is large, the first time point and the second time point are long from the start of charging, so the first The time difference between the 1 o'clock point and the 2 o'clock point can be regarded as constant and non-dependent on the amount of discharge, and the degree of deterioration can be accurately detected regardless of the amount of discharge.

In the first embodiment described above, the value of the voltage threshold value Vth is preferably set in a region where the lead battery is not gassing (in other words, in a region where the charging voltage rises with deterioration). This area can be said to be the area below the pole of the lead battery. The specific value of Vth in this region can be appropriately determined by experiments or the like in the field to which the present invention pertains.

In the first embodiment, although the charging rate is detected to be 100%. The time point is the second time point, but the detection time at the second time point can also be performed based on other criteria. For example, the detection threshold of the charging rate may be a value other than 100%, and the time when the detection threshold is reached may be the second time point, and the amount other than the charging rate may be used as a reference to reach the predetermined charging state. The time is 2 o'clock.

In the first embodiment, the degree of deterioration is used for the switching control of the charging process, but the usability of the degree of deterioration is not limited thereto. For example, it can also be used to calculate the amount of power that can be discharged at a certain amount of charge. Or, even if the degree of deterioration is converted into a numerical value to inform the user of the lead battery, it is also useful.

Embodiment 2.

The first embodiment is based on a constant current charging process, and the second embodiment is based on a constant voltage charging process. Hereinafter, differences between the first embodiment and the first embodiment will be described.

Fig. 4 is a graph showing an embodiment of the method of the embodiment. Unlike the second drawing, the graph of Fig. 4 schematically shows the relationship between the elapsed time and the current in the charging process of the constant voltage mode. The curve 21 is a curve of a lead battery of a new product (small degree of deterioration), and the curve 22 is a curve of a lead battery in a state in which the new product is deteriorated (the degree of deterioration is large). No matter which curve is the curve of the charging process after discharging the same amount of power.

In the lead battery (curve 21) having a small degree of deterioration, the current is larger than the predetermined current threshold Ith at the start of charging, and as the charging progresses, the current decreases, and Ith is reached at time t22 (first time point). The control device detects the first time point. After the first time, the charging is continued, and the charging rate reaches 100% at time t23 (second time point). Control device detection The second time is out. The time difference between the first time point and the second time point is t23-t22=T2a.

On the other hand, in the lead battery (curve 22) having a large degree of deterioration, the current reaches Ith at time t21 (first time point), and the charging rate reaches 100% at time t24 (second time point). The time difference between the first time point and the second time point is t24-t21=T2b (where T2b>T2a).

According to the first embodiment, the control device detects the degree of deterioration based on the elapsed time (T2a, T2b) between the first time point and the second time point. As described above, in the second embodiment, the degree of deterioration is detected based on the information (time, current, charging rate, and the like) acquired during charging. Therefore, the error of the degree of deterioration of the previous charging operation is not accumulated.

Further, in the second embodiment, as in the second embodiment, the charge control method of the lead battery can be used in the case where the normal charge processing and the equalization charge processing are selectively used.

The first embodiment is based on a constant current charging process, and the second embodiment is based on a constant voltage charging process. However, the present invention can also be applied to a charging method other than the above. For example, when the power mode is used, the time when the voltage reaches the voltage threshold value can be set as the first time point, and the time point when the current reaches the current threshold value can be set as the first time point. In addition, when the voltage is in the quasi-fixed voltage mode, the time when the voltage reaches the voltage threshold can be set as the first time point, and the time when the current reaches the current threshold value can also be set as the first time point. In other modes, the present invention can be applied as long as the relationship between voltage and current during charging is a given unique value.

Embodiment 3.

In the first and second embodiments, the charging method up to the first time point is The charging method up to the 2nd time is the same charging method. That is, both the first time point and the second time point are detected in the charging by the single charging method. In the third embodiment, the charging method up to the first time is different from the charging method up to the second time. Hereinafter, differences from Embodiments 1 and 2 will be described.

Fig. 5 is a graph showing an embodiment of the method of the embodiment. The graph of Fig. 5 schematically shows the relationship between the elapsed time and the current in the charging process in which the constant voltage method and the constant current method are combined.

At the start of charging, charging is performed by a constant voltage method (first charging method), and the current is larger than a predetermined current threshold Ith. As charging progresses, the current decreases, and Ith is reached at time t31 (first time). The control device detects the first time point during charging by the first charging method.

After the first time, the predetermined condition is satisfied at time t32, and accordingly, the control device switches the charging mode to the constant current mode (second charging mode). The predetermined conditions can be appropriately determined by those skilled in the art to which the present invention pertains. For example, when the first charging mode is the constant voltage mode, the current can be set to a predetermined switching threshold Ix (where Ix < Ith). Further, it is also possible to switch the charging method in accordance with the detection of the first time point.

Then, charging continues, and the charging rate reaches 100% at time t33 (2nd time). As described above, after the first time, the control device detects the second time point in the charging performed by the second charging method different from the first charging method. The time difference between the first time point and the second time point is t33-t31=T3.

In the first and second embodiments, the control device detects the degree of deterioration based on the elapsed time (T3) between the first time point and the second time point. As above, In the third embodiment, as in the first and second embodiments, the degree of deterioration is detected based on the information (time, current, charging rate, and the like) acquired during charging. Therefore, the error of the degree of deterioration of the previous charging operation is not accumulated.

Further, in the third embodiment, since different charging methods can be employed in accordance with the stage of the charging operation, the charging process can be configured elastically, and the degree of freedom of control is high.

Further, in the third embodiment, the charging control method for the lead battery is the same as the first and second embodiments, and the degree of deterioration can be utilized when the normal charging processing and the equalization charging processing are selectively used.

In the third embodiment, the first charging method may be any one of a constant current method, a constant voltage method, a constant power method, and a quasi-fixed voltage method. In the case of the constant current mode, the first time point is the time when the voltage reaches the voltage threshold value Vth. In the case of using the constant power mode or the quasi-fixed voltage mode, the first time point can be set as the time when the current reaches the current threshold Ith, and can also be set as the time when the voltage reaches the voltage threshold value Vth.

The second charging method may be any one of a constant current method, a constant voltage method, a constant power method, and a quasi-fixed voltage method as long as it is different from the first charging method.

In addition, different charging methods can be used in combination for both the first and second charging methods. Specifically, another charging method may be used before the first charging method, or another charging method may be used between the first charging method and the second charging method, or another charging method may be used after the second charging method. For example, charging may be started in the third charging mode, and then switching to the first charging mode in response to the predetermined condition being satisfied, detecting the first time point, corresponding to satisfying the predetermined time at the time of detection or after the detection. The condition is switched to the fourth charging mode, and then the second charging mode is switched in accordance with the predetermined condition, and the second time point is detected, and the fifth charging mode is switched at the time of detection or after the detection, in accordance with the predetermined condition being satisfied.

Embodiment 4.

In the first to third embodiments, the voltage threshold value Vth or the current threshold value Ith is a fixed value. The fourth embodiment is configured such that in the first to third embodiments, the threshold values vary with temperature. The control device may also be provided with a liquid temperature sensor that detects the liquid temperature of the lead battery.

Fig. 6 is a graph showing an embodiment of the method of the embodiment. This figure shows an example in which the voltage threshold value is a variable in the first embodiment. In this example, the voltage threshold Vth varies with temperature, and Vth = Vth0 + Cv. Where Vth0 is the threshold value (constant) and Cv is the temperature compensation term and is a function of temperature. Vth0 and Cv are memory means that can be stored in the control device.

The curve 41 and the curve 42 of Fig. 6 are the charging processes of the lead battery in the same degraded state after discharging the same amount of power. At normal temperature (curve 41), Cv = 0, and the voltage threshold is Vth = Vth0. The control device detects the first time point at time t41 and detects the second time point at time t42. The time difference between the first time point and the second time point is t42-t41=T4.

At low temperatures (curve 42), Cv > 0, and the voltage threshold is Vth > Vth0. At a low temperature, as shown in the figure, when the voltage changes differently from the normal temperature, the control device can be configured to detect the first time at the time t41 as in the normal temperature (curve 41) as long as the function of the temperature compensation term Cv is appropriately set. At the time point, the second time point is detected at time t42. The time difference between the first time point and the second time point is t42-t41=T4. In addition, in this example, the time difference T4 is Although it is equal to the normal temperature and the low temperature, it is not necessarily set to be equal, and Cv can be defined in such a manner that the error of the time difference caused by the temperature is reduced.

Fig. 7 is a view showing an example in which the current threshold value is changed in the second embodiment. In this example, the current threshold Ith varies with temperature, and Ith = Ith0 + Ci. Where Ith0 is the threshold value (constant) and Ci is the temperature compensation term and is a function of temperature. Ith0 and Ci can be stored in the memory means of the control device.

The curve 51 and the curve 52 of Fig. 7 are the charging processes of the lead batteries in the same degraded state after discharging the same amount of power. At normal temperature (curve 51), Ci = 0, and the current threshold is Ith = Ith0. The control device detects the first time point at time t51 and detects the second time point at time t53. The time difference between the first time point and the second time point is t53-t51=T5a.

At low temperatures (curve 52), Ci < 0 and the voltage threshold is Ith < Ith0. The control device detects the first time point at time t52 and detects the second time point at time t54. The time difference between the first time point and the second time point is t54-t52=T5b. At a low temperature, as shown in the figure, the change in current is different from the normal temperature, but as long as the function of the temperature compensation term Ci is appropriately set, T5a = T5b can be configured. In this example, although the time difference is equal to the low temperature at normal temperature and T5a=T5b, it is not necessarily set to be equal, and Ci may be defined in such a manner that the error of the time difference caused by the temperature becomes smaller.

In the first to third embodiments, the control device detects the degree of deterioration based on the elapsed time (T5a, T5b) between the first time point and the second time point. As described above, the fourth embodiment is also the same as the first to third embodiments, depending on the charging. The acquired information (time, voltage, current, temperature, charging rate, etc.) detects the degree of deterioration, and therefore does not accumulate errors in the degree of deterioration of the previous charging operation.

Further, in the fourth embodiment, since the degree of deterioration is compensated based on the liquid temperature, the detection accuracy of the degree of deterioration can be further improved.

Further, in the charging method of the lead battery, in the fourth embodiment, as in the first to third embodiments, the degree of deterioration can be utilized when the normal charging process and the equalizing charging process are selectively used.

Embodiment 5.

In the first to fourth embodiments, the degree of deterioration is detected based on the elapsed time between the first time point and the second time point (that is, the amount of change in time). In the fifth embodiment, in the first to fourth embodiments, the degree of deterioration is detected based on the amount of change in the physical quantity other than the elapsed time. Hereinafter, differences from Embodiments 1 to 4 will be described.

Fig. 8 is a graph showing an embodiment of the method of the embodiment. In this embodiment, in the first embodiment, the degree of deterioration is detected based on the amount of change in the amount of charge, not the time. The curve 61 is a curve of a lead battery of a new product (small degree of deterioration), and the curve 62 is a curve of a lead battery in a state in which the new product is deteriorated (in the degree of deterioration), and the curve 63 is a state in which the deterioration is more (the degree of deterioration is large). The curve of the lead battery. No matter which curve is the curve of the charging process after discharging the same amount of power.

In the lead battery (curve 61) having a small degree of deterioration, the voltage does not reach the predetermined voltage threshold value Vth at the start of charging, and as the charging progresses, the voltage rises and reaches the Vth at the charging amount e63 (first time point). The control device detects the first time point. After the 1st hour, charging continues. The amount of charge reaches a predetermined value at the charge amount e64 (second time point). The predetermined value is, for example, a charge amount equivalent to 100% of the charge rate. The control device detects the second time point. The amount of change in the amount of charge between the first time point and the second time point is e64-e63=E6a.

In the lead battery (curve 62) in the degree of deterioration, the charge amount e62 (first time point) which is smaller than the charge amount e63 reaches Vth. The amount of change in the amount of charge between the first time point and the second time point is e64-e62=E6b (where E6b>E6a). Further, in the lead battery (curve 63) having a large degree of deterioration, the charge amount e61 (first time point) which is smaller than the charge amount e62 reaches Vth. The amount of change in the amount of charge between the first time point and the second time point is e64-e61=E6c (where E6c>E6b).

The control device detects the degree of deterioration based on the amount of change (E6a, E6b, E6c) of the amount of charge between the first time point and the second time point. The amount of change can be calculated by integrating the current values from the first time point to the second time point. Alternatively, it can be calculated by subtracting the amount of charge at the first time point from the amount of charge at the second time point.

As described above, in the fifth embodiment, as in the first to fourth embodiments, the degree of deterioration is detected based on the information (voltage, current, charge amount, and the like) acquired during charging. Therefore, the degree of deterioration of the previous charging operation is not accumulated. error.

Further, in the fifth embodiment, since the amount of charge is used as a reference and not based on time, the calculation error of the conversion time and the amount of charge can be reduced, and the calculation of the calculation method can achieve more accurate determination.

Further, in the fifth embodiment, as in the fifth embodiment, the charge control method for the lead battery can be selectively used. This degree of deterioration is utilized in the charging process and the equalization charging process.

In the fifth embodiment, the degree of deterioration is detected based on the amount of change in the amount of charge between the first time point and the second time point. In the modified example, the charging rate between the first time point and the second time point may be used. The amount of change to detect the degree of deterioration.

In addition, in the fifth embodiment, the charge amount or the charge rate at the second time can be determined in advance as a charge rate of 100%, for example, and therefore a predetermined value (charge amount or charge rate) can be used and omitted. The step of detecting the second time point (the detection of the charge amount or the charge rate at the second time point). In other words, it is also possible to detect the degree of deterioration based on the amount of charge or the charging rate at the first time point at the first time point when the voltage or current is detected to reach the predetermined threshold value during charging.

At this time, the degree of deterioration can be detected by subtracting the charge amount or the charge rate at the first time point by a predetermined reference charge amount or a reference charge rate. For example, when the reference at the second time point is set to "the state in which the charging rate is 100%", it is possible to subtract the first time point by 100% before the second time point is actually detected after detecting the first time point. The degree of deterioration is detected based on the result of the charging rate.

11 to 13‧‧‧ Curve

Vth‧‧‧ voltage threshold (predetermined threshold)

T11 to t13‧‧‧ (1st hour)

Time t14‧‧‧ (2 o'clock)

T1a, T1b, T1c‧‧‧ time difference (time)

Claims (5)

A method for detecting a deterioration degree of a lead battery, comprising the steps of: detecting a first time point when a voltage or a current reaches a predetermined threshold value in charging by the first charging method; After the time, in the charging by the first charging method or the charging by the second charging method different from the first charging method, the step of reaching the second time point of the predetermined charging state is detected; and The elapsed time between the first time point and the second time point, the amount of change in the amount of charge, or the amount of change in the charge rate, the step of detecting the degree of deterioration. The method of claim 1, wherein the degree of deterioration is detected based on the elapsed time. A method for detecting a deterioration degree of a lead battery, comprising the steps of: detecting a first time point when a voltage or a current reaches a predetermined threshold value during charging; and charging amount according to the first time point or The charging rate is a step of detecting the degree of deterioration. The method of any one of claims 1 to 3, wherein the degree of deterioration is detected based only on information related to the previous charging process. A method of selectively controlling a charge control of a lead battery using a normal charge process and a balanced charge process, comprising the steps of: detecting the degree of deterioration by the method of any one of claims 1 to 4. And the step of performing a normal charging process or performing a balanced charging process at the next charging according to the degree of deterioration and the number of times of normal charging processing performed after the last implemented equalization charging process.