JP2003204632A - Charging method, storage battery system, and air- conditioning system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make use of low-cost, general-purpose electronic components and detect overcharging and insufficient charging of a valve-regulated lead acid battery with accuracy. <P>SOLUTION: A threshold time τ<SB>2</SB>and a threshold time τ<SB>1</SB>are set as margins, respectively before and after time t<SB>3</SB>, when charging to a usage-based charging amount is completed. If the time for peaking falls within the margins, a first charging is decided as being appropriate. If the time for peaking is before the time when charging to the usage-based charging amount is completed beyond the corresponding margin, the first charging is decided as being overcharging. If the time for peaking is after the time when charging to the usage-based charging amount is completed beyond the corresponding margin, the first charging is decided as being insufficient charging. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a storage battery, and more particularly to a technique for charging a sealed lead storage battery.

[0002]

2. Description of the Related Art Various charging methods for charging a lead acid battery have been devised. As a charging method that secures a predetermined discharge amount and has a high charging efficiency, it is desirable to charge the lead storage battery with a charge amount such that the lead storage battery does not reach a fully charged state but is incompletely charged, while depending on the discharge amount.

However, if only such a charging method is adopted and charging and discharging are repeated, the lead storage battery becomes insufficiently charged,
This leads to a decrease in capacity. Therefore, overcharge is regularly adopted to refresh the lead acid battery.

When charging a lead-acid battery in which charge and discharge are alternately repeated, the charge amount obtained by multiplying the discharge amount P discharged after the previous charge by a predetermined coefficient x (in this case, " The lead-acid battery is charged with x · P. In this case, such charging is referred to as first charging. It is desirable that the first charging be incomplete charging as described above, and for example, the predetermined coefficient x is selected to be 1.02 as a default value.

Then, in overcharging for refreshing (this is referred to as "second charging" in this case), the charge amount x.
The lead storage battery is overcharged with a charge amount x · P + Q obtained by adding a predetermined charge amount Q to P. For example, the predetermined charge amount Q is set to 10% of the rated discharge amount of the lead storage battery. The second charging is not continuously performed, but is performed at least once between the first charging.

[0006]

In order to accurately perform the first charging, the discharge amounts P ₁ , P ₂ ,
P ₃ , ... or the amount of charge after each x x P ₁ , x x P
_It is necessary to accurately grasp ₂ , x · P ₃ , .... Otherwise, in the first charging, not complete charging but full charging or overcharging may be performed, or even incomplete charging may result in insufficient charging. If the first charge is overcharged, the charge efficiency is deteriorated, and if the charge is insufficient, deep discharge is likely to occur as the charge / discharge is repeated. This shortens the life of the lead acid battery or makes it impossible to secure the rated discharge amount.

In order to accurately grasp the charge / discharge amount at each time, it is necessary to measure the charge / discharge current with high accuracy (for example, about ± 1%). For example, when the rated charge / discharge amount is constantly repeated, a certain degree of prediction is possible by tracking the trend of the lead-acid battery voltage immediately before the end of charging and the discharge end-voltage. However, the above-mentioned high accuracy cannot be obtained.

In order to measure the charging / discharging current with high accuracy, a detection circuit using an effective current sensor and fine adjustment of the initial value are necessary, which is expensive and time-consuming.

In view of such circumstances, the present invention provides a technique for utilizing inexpensive general-purpose electronic parts and detecting with high accuracy overcharge or undercharge of a sealed lead-acid battery. Further, it also provides a technique for appropriately setting the charge amount in the first charge when overcharge or insufficient charge is detected. Such a technique can be applied to a storage battery system including the sealed lead storage battery. Therefore, it is also applicable to an air conditioning system including the storage battery system.

[0010]

[Means for Solving the Problems] Claim 1 of the present invention
Is a method of charging a sealed lead-acid battery (220) that is repeatedly charged and discharged alternately, and has a predetermined coefficient (x) with respect to the discharge amount (P) discharged after the previous charging. A first charge for charging the sealed lead-acid battery with a charge amount (x · P) obtained by multiplying by, and a charge amount (x · P + Q) obtained by adding a predetermined charge amount (Q) to the charge amount And a second charge for overcharging the sealed lead-acid battery. The second charging is performed at least once between the first charging. The state of charge of the sealed lead acid battery charged by the first charging is determined based on the time when the voltage of the sealed lead acid battery reaches a peak in the second charging.

According to claim 2 of the present invention,
The charging method according to claim 1, wherein (a) the peak voltage of the sealed lead-acid battery in the second charging is:
The sealed lead-acid battery is obtained when the second charge is obtained (s ₃ ) later than the time (t ₃ ) at which the charging of the sub-charge amount is finished and after a first time (τ ₁ ). Includes a step of determining that the first charge is insufficiently charged.

According to claim 3 of the present invention,
The charging method according to claim 2, wherein the step (a) is performed.
In, when the sealed lead-acid battery is determined to be insufficiently charged by the first charging, the predetermined coefficient adopted in the first charging executed thereafter is increased and updated. To do.

According to claim 4 of the present invention,
The charging method according to claim 2 or 3, wherein (b)
The peak of the voltage of the sealed lead-acid battery in the second charge exceeds the second time (τ ₂ ) earlier than the time when the charging of the secondary charge amount ends in the second charge (s _2). ) If obtained, the method further comprises the step of determining that the sealed lead-acid battery is overcharged by the first charging.

According to claim 5 of the present invention,
The charging method according to claim 4, wherein the step (b) is performed.
In, when it is determined that the sealed lead-acid battery is overcharged by the first charging, the predetermined coefficient used in the first charging performed thereafter is reduced and updated. .

According to claim 6 of the present invention,
The charging method according to any one of claims 1 to 3, wherein at least the second charging is performed using a gradually decreasing charging current, and the voltage of the sealed lead-acid battery is reduced. The maximum value of the voltage of the sealed lead-acid battery at the final stage (T _E ) is adopted as the peak.

According to claim 7 of the present invention,
The charging method according to any one of claims 4 and 5, wherein at least the second charging is performed using a gradually decreasing charging current, and the voltage of the sealed lead-acid battery is reduced. The maximum value of the voltage of the sealed lead-acid battery at the final stage (T _E ) is adopted as the peak.

According to claim 8 of the present invention,
8. The charging method according to claim 7, wherein the second-stage first stage to the final stage first half (T ₁ , T ₂ , T ₃ ) of the _second charge is charged with the _secondary charge amount, and the final stage first half is charged. When the time (T ₃ ) is shorter than the predetermined time, exceptionally in the step (b), the overcharging is not performed by the first charging.

According to claim 9 of the present invention,
The charging method according to claim 6, wherein when the voltage of the sealed lead storage battery reaches a predetermined voltage, the charging in the first stage ends.

A tenth aspect of the present invention is a storage battery system that employs the charging method according to any one of the first to ninth aspects and that includes the sealed lead storage battery.

According to a tenth aspect of the present invention, there is provided an air conditioning system including the storage battery system according to the tenth aspect.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION A. Configuration to which the present invention is applicable. FIG. 1 is a block diagram showing a configuration of a storage battery unit 200 in which the charging method according to the present invention is adopted and an air conditioning system including the storage battery system 200.

The air conditioning system is an outdoor unit 10
0, an indoor unit 300 is also provided. The outdoor unit 100 includes a compressor 103, and the indoor unit 300 performs an air conditioning operation on an interior (not shown) using a refrigerant (not shown) compressed here.

The storage battery unit 200 includes a storage battery 220 to be charged / discharged, a bidirectional converter 210 for charging / discharging the storage battery 220, and a charging / discharging control unit 230 for controlling charging / discharging.

The outdoor unit 100 further includes an AC / DC converter 101 and an inverter 102. AC
The / DC converter 101 is, for example, a three-phase AC commercial power source 4
00, AC / DC conversion, and inverter 1
02 or the bidirectional converter 210, DC power is supplied. The inverter 102 is operated by using the DC power supplied from the bidirectional converter 210 and the DC power supplied from the AC / DC converter 101 together to drive the compressor 103.

The storage battery unit 200 is used in the AC / DC converter 10 at a time when the electricity charge is low, for example, at night.
DC power is received from the battery 1, and the built-in storage battery 220 is charged through the bidirectional converter 210. At this time, the inverter 102 is not operated. On the other hand, the inverter 10
Charging is not performed during the time period in which No. 2 is operated, and DC power is supplied to the inverter 102 together with DC power supplied by the AC / DC converter 101.

The storage battery 220 is constructed as an assembled battery, for example, and is constructed by connecting a plurality of unit cells 221 in series.

FIG. 2 is a circuit diagram showing a structure of a portion related to charging / discharging of the storage battery 220. Here, the inverter 102
However, the configuration of supplying DC power from the AC / DC converter 101 is omitted.

The bidirectional converter 210 includes a charging converter 211 for charging and a converter 212 for discharging.
And a charging / discharging changeover switch 213 that is switched between when the storage battery 220 is charged and when it is discharged. That is, at the time of charging, under the control of the charge / discharge control unit 230, the AC / DC converter 101 is controlled by the charging converter 211 via the charging / discharging changeover switch 213.
The storage battery 220 is charged with the electric power obtained from Further, at the time of discharging, under the control of the charge / discharge control unit 230, the storage battery 220 is discharged to the inverter 102 by the discharge converter 212 via the charge / discharge changeover switch 213.

The charge current and the voltage of the storage battery 220 are monitored by the charge / discharge control unit 230 as needed. The charge / discharge control unit 230 has a function of causing the bidirectional converter 210 to control a charge / discharge current to a constant current, a function of switching a charge / discharge current value, and a function of managing integration of charge / discharge amounts. These functions are shown in FIG. 2 as a "constant current control function", a "charge / discharge current switching function", and a "charge / discharge amount integration management function", respectively.

B. Basic idea of the present invention. FIG. 3 is a graph showing the basic idea of the present invention. In the figure, the curves L ₁ , L ₂ and L ₃ all have a common horizontal axis,
Different vertical axis. The horizontal axis shows the time based on the time when the second charging is started, and the vertical axis shows the voltage of the storage battery 220. The curves L ₁ , L ₂ , and L ₃ are the storage battery 220.
Shows a case where proper incomplete charge, overcharge, and improper (that is, the charge amount is lower than the appropriate case) incomplete charge by the first charge, respectively.

The curves L ₁ , L ₂ and L ₃ all show the voltage during charging when the second charging is performed, and show the case where the previous discharge amount P is common. Then, the charge amount x · P (where x is a predetermined coefficient and the default value is 1.02, for example), and is the time t ₃ with reference to the charge start time.
The point of being charged up to that point and the point of being immediately after that being charged with a predetermined charge amount Q in the period T _Q of time t _{3 to} t _E are common to the curves L ₁ , L ₂ and L ₃ .

After the start of charging, the charging of the secondary charging amount is performed by using the charging current that gradually decreases. The gradual reduction of the charging current is performed by the charging converter 211 based on the “constant current control function” and the “charging / discharging current switching function” of the charging / discharging control unit 230. Not only in the second charging but also in the case of charging the secondary charging amount in the first charging, it is desirable to charge using the charging current that gradually decreases. This is because charging using a charging current that gradually decreases improves charging efficiency.

Although the case of charging the sub-charge amount in three stages is illustrated here, other stages may be adopted as long as the number of stages is plural. For example, in the first stage it is 0.25 CA,
The second stage is 0.1 CA, the third stage is 0.05 CA,
The charging current is set for each. That is, if the rated capacity of the storage battery 220 is 70 Ah, the charging currents of the first stage, the second stage, and the third stage are set to 17.5 A, 7 A, and 3.5 A, respectively.

[0034] In Figure 3, the charging of the first stage in the period T ₁ of the time 0 to t _1, the charge of the second stage in the period T ₂ of the times t ₁ ~t _2, the charging of the third-stage time t in the period T ₃ of ₂ ~t _3, may have been carried out respectively are illustrated.

As a condition for shifting from the first stage to the second stage, it can be adopted that the voltage of the storage battery 220 has reached a predetermined voltage, which contributes to simple and quick charging. This predetermined voltage is
For example, the voltage of the storage battery 220 in a state in which the storage battery 220 can be discharged at a capacity of 80% of the rated capacity can be adopted. The charge / discharge control unit 230 measures the voltage of the storage battery 220.
It is detected by the voltage detecting end of.

The conditions for shifting from the second stage to the third stage are as follows:
It can be adopted that the storage battery 220 is charged with a charge amount of 92% of the previous discharge amount. The discharge amount and the charge amount can be measured by the “charge / discharge amount integrated management function” of the charge / discharge control unit 230.

The charging current used in the third stage for charging the sub-charge amount is also used when the predetermined charge amount Q is charged. Therefore, the charging period of the third stage, together with the period of charging the predetermined charge amount Q, should be understood as the final stage of the second charging that employs a constant charging current (here, 0.05 CA). You can The charging period of the third stage can be understood as the first half of the final stage of the second charging. According to such an understanding, the charge amount is charged from the first stage of the second charge to the first half of the final stage, and the predetermined charge amount Q is added in the latter half of the final stage of the second charge. It can be understood when it is charged.

Now, in the second charging, the storage battery 22
Since the voltage of 0 is overcharged, there is a time to reach the fully charged state from time 0 to t _E. In general, a sealed lead-acid battery has a characteristic that its voltage reaches a peak when it reaches a fully charged state, and then decreases. As described above, it is desirable that the first charging is incomplete charging while the second charging is overcharging. Therefore, as shown by the curve L1, the time s _{1 at} which the peak indicating the fully charged state occurs is the predetermined charge amount Q.
Within the period T _Q (time t _{3 to} t _E ) for charging the battery.

On the other hand, in the storage battery 220 that is in the overcharged state in the first charge,
It becomes an overcharged state when it is charged by the secondary charge amount. Therefore, the curve L ₂
, A time s _{2 at} which a peak indicating a fully charged state occurs
There exists a time t ₃ before indicating the completion of charging metered charge amount.

Alternatively, in the storage battery 220 that is excessively insufficiently charged in the first charge, the time s _{2 at} which a peak indicating a fully charged state occurs as shown by the curve L2 is the time at which the charging of the _secondary charge amount ends. Exists well after t ₃ .

As described above, regarding the state of charge of the storage battery 220, the time when the peak of the voltage is taken in the second charging is the time t ₃ which is the reference time which is the time required to charge the quantity of charge. It can be judged by comparing.

It is also possible to determine whether the voltage of the storage battery 220 has reached a peak by observing the case where the voltage changes from a tendency of rising as the charging proceeds to a tendency of falling. This obtains the maximum value of the voltage of the storage battery 220 over time.

However, particularly when charging is performed by gradually reducing the charging current, the voltage of the storage battery 220 takes a maximum value with respect to the passage of time at the time of switching of that stage. This is because while the voltage for charging tends to increase, the voltage tends to decrease if the charging current changes in the decreasing direction. This can be seen in FIG. ₃ in common with the curves L ₁ , L ₂ , and L ₃ at times t ₁ and t ₂ . Therefore, when the charging current is gradually reduced to perform charging, the storage battery 220 is simply detected by detecting the maximum value.
It will make a mistake in the judgment of the charging state of.

In such a case, the period T ₃ of the final stage, that is, the third stage for charging the secondary charge amount, and the predetermined charge amount Q
The maximum value may be detected in the total period T _E of the period T _Q for charging the battery. Since the charging current is constant in the final stage as described above, the reason why the maximum value is taken is not considered to be a decrease in the charging current, but it is considered to be due to reaching the fully charged state.

When it is determined that the storage battery 220 is overcharged by the first charge by the above determination at the time of the second charge, the predetermined coefficient x for determining the amount of secondary charge is set. Reduce. This can reduce the possibility that the storage battery 220 will be overcharged in the next first charging. On the contrary, when it is determined that the storage battery 220 is insufficiently charged due to the first charging, the predetermined coefficient x for determining the secondary charge amount is increased. This can reduce the possibility that the storage battery 220 will be insufficiently charged in the first charging next time.

Moreover, it is not necessary to accurately measure the discharge amount P in each discharge. Although it is necessary to accurately obtain various times, such a function can be performed even by an inexpensive general-purpose electronic component.

From a higher perspective, the state of charge of the sealed lead acid battery charged by the first charging is determined based on the time at which the voltage of the sealed lead acid battery peaks during the second charging. Therefore, it can be said that the state of charge of the sealed lead-acid battery charged by the first charge can be detected without accurately measuring the charge / discharge amount.

C. First embodiment. FIG. 4 is a flowchart showing the charging method according to this embodiment. The measurement and judgment shown below can be performed by the charge / discharge control unit 230. The determination of the charge state of the storage battery 220 is performed in the second charge. The second charging is performed in a plurality of stages in which the charging current is gradually reduced.

First, in step S11, it is determined whether or not the final stage of the second charging has been reached. According to FIG. 3, it is determined whether the time t ₂ has been reached. In this embodiment, the fully charged state of the storage battery 220 is determined by the maximum value of the voltage of the storage battery 220, so the maximum value in the final stage of the second charging is detected as described above. Therefore, unless the final stage of the second charging is reached, step S11 is repeated and the maximum value of the voltage is not detected.

If the final stage of the second charging is reached, step S1
In step 2, it is determined whether the storage battery voltage is increasing.
If it is rising, since it has not reached the maximum value yet, the process proceeds to step S13. In step S13, it is determined whether the charge amount has been charged. If not, the process returns to step S12, and it is determined whether the storage battery voltage is still increasing.

When the subordinate charge amount is charged,
Proceeding to step S14, a predetermined amount of charge Q is charged. Step S14 is executed in parallel with the execution of the subsequent steps.

The fact that the storage battery voltage is still rising means that it has reached step S14. Therefore, it is determined in step S15 again whether the storage battery voltage is rising in the same manner as in step S12. Then, step S15 is repeatedly executed until the storage battery voltage stops increasing.

Since the predetermined charge amount Q is set so that the second charge is always overcharged, there is always a time point when step S15 is exited, and it is determined that the peak of the storage battery voltage has been reached at that time point ( Step S16).

Then, the process proceeds to step S17, and it is determined whether the value obtained by subtracting the time when the charging of the secondary charge amount is finished from the time when the peak is reached is larger than a predetermined threshold time τ ₁ . According to FIG. 3, the time obtained by subtracting the time t _{3 at} which the charging of the secondary charge amount ends from the time S ₃ at which the storage battery voltage reaches the peak on the curve L ₃ is
Greater than the threshold time τ ₁ .

Therefore, if the affirmative determination is made in step S17, it is determined that the charging is insufficient as indicated by the curve L ₃ . In this case, the predetermined coefficient x for determining the secondary charge amount is increased and updated (step S19). This reduces the possibility of insufficient charging in the next first charging.

On the other hand, the time obtained by subtracting the time t ₃ when the charging of the secondary charge amount is finished from the time S ₁ when the storage battery voltage reaches the peak on the curve L ₁ is smaller than the threshold time τ ₁ . From time S ₂ of battery voltage curve L ₂ has reached the peak, the time obtained by subtracting the time t ₃ when the charging of usage-based charge amount is completed becomes negative, less than the threshold time tau ₁ Again . However, when the process proceeds from step S13 to step S14, the case where the above subtraction time becomes negative (case of curve L ₂ ) is excluded. Therefore, when a negative determination is made in step S17, it is determined that the charging state is appropriate as indicated by the curve L ₁ (step S20).

Whether or not steps S19 and S20 are executed, the determination of the state of charge is completed.

If a negative determination is made in step S12 before it is determined in step S13 that the charge amount has been charged, the process proceeds to step S21, and similarly to step S16, the storage battery voltage It is determined that the peak has been reached. After that, step S
23 is executed in the same manner as in step S13, and the secondary charge amount is charged. After that, step S24 is step S
This is executed in the same manner as in 14, and a predetermined amount of charge Q is charged. Step S24 is executed in parallel with the execution of the subsequent steps. However, step S24 may be omitted because it has already been overcharged due to the charge amount.

Then, in step S25, it is determined whether or not a value obtained by subtracting the time at which the peak is reached from the time at which the charging of the _secondary charge amount is completed is larger than a predetermined threshold time τ ₂ . According to FIG. 3, the time obtained by subtracting the time S ₂ at which the storage battery voltage reaches the peak on the curve L ₂ from the time t ₃ at which the charging of the _secondary charge amount ends is obtained from the threshold time τ ₂ . Is also big. Therefore step S
When the determination is affirmative in 25, it is determined that the battery is overcharged as indicated by the curve L ₂ . In this case, the predetermined coefficient x that determines the secondary charge amount is reduced and updated (step S26). This reduces the possibility of overcharge in the next first charge. The threshold time τ ₂ can be set to a time of 0 or more.

If a negative determination is made in step S25, the process proceeds to step S20, it is determined that the state is normal, and the predetermined coefficient x is not updated.

As described above, the threshold time τ ₂ and the threshold time τ ₁ are set as margins before the time t ₃ at which the charge of the _secondary charge amount is completed, respectively, and the time at which the peak is reached. Is within the margin, it is determined that the first charging is appropriate. On the other hand, when the time when the peak is reached is before the time when the charging of the secondary charge amount is completed beyond the margin, it is determined that the first charge is overcharge. On the other hand, if the time at which the peak is reached is after the time at which the charging of the secondary charge amount ends after exceeding the margin, it is determined that the first charge is insufficient. The predetermined times τ ₁ and τ ₂ are set to 30 minutes, for example.

The increase / decrease of the value of the predetermined coefficient x is updated, for example, in 0.01 steps. For example, the default value is 1.0
If the value is set to 2, and then step S19 is executed for the first time without executing step S26, the value of the predetermined coefficient x becomes 1.03, and step S19 is executed.
When step S26 is executed for the first time without executing, the value of the predetermined coefficient x becomes 1.01.

D. Second embodiment. Even when the time at which the storage battery voltage reaches the peak is before the time at which the charge of the _secondary charge amount ends after the threshold time τ ₂ is exceeded, the first charge is overcharged. It may be desirable not to judge.

FIG. 5 shows the voltage during charging when the second charging is performed, and the times t ₁ , t ₂ , t ₃ and t _E are used in the same meaning as in the first embodiment. . That charge of the first stage in the period T ₁ of the time 0 to t _1, the charge of the second stage in the period T ₂ of the times t ₁ ~t _2, the charging of the third stage time t ₂ ~
In the period T ₃ of t ₃ , the charging of the predetermined charge amount Q is performed at the time t
In the period T _E of ₃ ~t _E, it has been made, respectively. The time s ₄ at which the storage battery voltage reaches the peak exists before the time t ₃ at which the _secondary charge amount is charged and exceeds a predetermined time τ ₂ before.

However, in the graph shown in FIG. 5, the charge amount P at the previous time is small, and therefore, the charge amount x.multidot.
The case where P is also small is shown. Since the charging current in each stage is fixed, the periods T ₁ , T ₂ , and T ₃ become shorter as the amount of charge amount x · P decreases. In such cases,
It was found that the storage battery voltage had a tendency to reach a peak by the time the charge amount was charged, although it was not overcharged.

Therefore, when the period T ₃ during which the third stage charging is performed (which is grasped as the first half of the final stage charging of the second charging as described above) is shorter than the predetermined time τ ₃ , Should not be judged to be overcharged.

FIG. 6 shows a part of the flowchart according to this embodiment. In the present embodiment, the flowchart of FIG. 4 is adopted as in the first embodiment, but step S30 is inserted between step S25 and step S26.

[0068] Step S30 is the end time t ₃ of the meter-rate charging amount charged minus the start time t ₂ of the charging of the last stage to determine whether longer than a predetermined time tau _3. If an affirmative determination result is obtained, the amount of charge x.P has been relatively large, and therefore the process proceeds to step S26 in order to perform the same process as the flowchart of FIG. If a negative determination result is obtained, it means that the secondary charge amount x · P was relatively small, and thus the process proceeds to step S20 for determining a normal state.

As described above, in the present embodiment, when the previous discharge amount is small, the error of determining that the first charging is overcharging despite the normal charging is avoided. can do.

[0070]

According to the charging method of the first aspect of the present invention, the state of charge of the sealed lead-acid battery charged by the first charging is detected without accurately measuring the charge / discharge amount. be able to.

According to the charging method of the second aspect of the present invention, since the actual capacity decreases when the lead storage battery is used in the incompletely charged state, it can be charged to at least the fully charged state by the second charging. desirable. On the other hand, in a lead-acid battery in which charge and discharge are alternately repeated, the charge amount is not deteriorated while ensuring the discharge amount. It is desirable that In the sealed lead-acid battery, the voltage rises until the fully charged state is obtained, but if charging is continued after the fully charged state is obtained, it becomes overcharged and the voltage drops.

Therefore, in the second aspect of the present invention, when the second charge is obtained later than the first time with respect to the time when the charge of the secondary charge amount is finished, the secondary charge is performed with the secondary charge amount. It is determined that the charging of 1 is insufficient.

According to the charging method of the third aspect of the present invention, it is possible to avoid insufficient charging due to the first charging.

According to the charging method of the fourth aspect of the present invention, in the invention of the fourth aspect, the peak of the voltage of the sealed lead-acid battery occurs earlier than the second time with respect to the reference time. For the first charge, it is determined that the first charge, which is charged with the secondary charge amount, is overcharged.

As a result, the overcharged state of the sealed lead storage battery can be detected without accurately measuring the charge / discharge amount.

According to the charging method of the fifth aspect of the present invention, overcharging due to the first charging can be avoided.

According to the charging method according to claims 6 and 7 of the present invention, the maximum value due to the stepwise decrease of the charging current is changed to the maximum value due to the fact that the fully charged state is obtained. Avoid misjudging as a value.

According to the charging method according to the eighth aspect of the present invention, it is determined that overcharging is performed despite normal charging of the first charging when the previous discharge amount is small. Avoid mistakes.

The charging method according to claim 9 of the present invention contributes to simple and quick charging.

According to the storage battery system of the tenth aspect of the present invention, it is possible to detect an overcharged or insufficiently charged state of the sealed lead storage battery without accurately measuring the charge / discharge amount.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration to which the present invention is applicable.

FIG. 2 is a circuit diagram showing a configuration of a portion related to charge / discharge of a storage battery.

FIG. 3 is a graph showing the basic idea of the present invention.

FIG. 4 is a flowchart showing a charging method according to the first embodiment of the present invention.

FIG. 5 is a graph illustrating a charging method according to a second embodiment of the present invention.

FIG. 6 is a flowchart showing a charging method according to the second embodiment of the present invention.

[Explanation of symbols]

P discharge amount Q predetermined charge x predetermined coefficient xP P charge amount 200 storage battery unit 220 Sealed lead acid battery 230 Charge / Discharge Control Unit

Continued front page    F term (reference) 3L060 AA08 CC10 DD08 EE01 EE21                       EE45                 5G003 AA01 BA01 CA06 CA17 GB03                       GB06 GC05                 5H028 AA01 HH10                 5H030 AA01 AS01 BB01 FF42 FF43                       FF52

Claims (11)

[Claims] 1. A method of charging a sealed lead-acid battery (220), wherein charging and discharging are alternately repeated, wherein a predetermined coefficient (x) is given to a discharge amount (P) discharged after a previous charging. A first charge for charging the sealed lead-acid battery with a charge amount (x · P) obtained by multiplying by, and a charge amount (x · P + Q) obtained by adding a predetermined charge amount (Q) to the charge amount Second overcharge the sealed lead-acid battery with
Charging is performed, the second charging is performed at least once between the first charging, based on the time at which the voltage of the sealed lead-acid battery peaks in the second charging, A charging method for determining a state of charge of the sealed lead-acid battery charged by the first charging. 2. (a) The peak of the voltage of the sealed lead-acid battery in the second charging is first than the time (t ₃ ) at which the charging of the charge amount is completed in the second charging. The method of determining that the sealed lead-acid battery is insufficiently charged by the first charging when the battery is obtained late (s ₃ ) after exceeding the time (τ ₁ ) of 1.
The charging method described. 3. In the step (a), if it is determined that the sealed lead-acid battery is insufficiently charged by the first charging, it is adopted in the first charging executed thereafter. The charging method according to claim 2, wherein the predetermined coefficient is updated by increasing the predetermined coefficient. 4. (b) The peak of the voltage of the sealed lead-acid battery in the second charging is the second time (τ ₂₎ from the time when the charging of the amount of charge according to the second charging is completed. 4. The method further comprises the step of determining that the sealed lead-acid battery is overcharged by the first charging if the battery is obtained (s ₂ ) earlier than ().
The charging method described. 5. In the step (b), if it is determined that the sealed lead-acid battery is overcharged by the first charging, it is adopted in the first charging performed thereafter. The charging method according to claim 4, wherein the predetermined coefficient is reduced and updated. 6. At least in the second charging,
The battery is charged using a charging current that gradually decreases, and the peak of the voltage of the sealed lead-acid battery adopts a maximum value of the voltage of the sealed lead-acid battery at the final stage (T _E ). Item 5. The charging method according to any one of item 3. 7. At least in the second charging,
The battery is charged using a charging current that gradually decreases, and the peak of the voltage of the sealed lead acid battery adopts the maximum value of the voltage of the sealed lead acid battery at the final stage (T _E ). Item 6. The charging method according to any one of items 5. 8. The first half of the second charging to the first half of the final stage (T ₁ , T ₂ , T ₃ ) to be charged with the subordinate charge amount, and the first half of the final stage (T ₃ ) The charging method according to claim 7, wherein, when is shorter than a predetermined time, the charging is not overcharged by the first charging exceptionally in the step (b). 9. The charging method according to claim 6, wherein when the voltage of the sealed lead storage battery reaches a predetermined voltage, the charging in the first stage is completed. 10. A storage battery system that employs the charging method according to any one of claims 1 to 9 and includes the sealed lead storage battery. 11. An air conditioning system comprising the storage battery system according to claim 10.