JP6920157B2 - Charge control device - Google Patents

Description

The present invention relates to a charge control device.

As a charging method for a secondary battery, a constant current constant voltage charging method is known. In this charging method, constant current charging is performed first, and then constant voltage charging is performed. Further, when charging at a constant voltage, the charging end condition is that the charging current value is equal to or less than a predetermined value.

However, when the above termination condition is applied to a secondary battery that has been deteriorated by repeating charging and discharging a plurality of times, charging may be terminated when the battery capacity that can be charged is still left. Therefore, the user may not be satisfied with the usability.

In response to such a problem, for example, in Patent Document 1, in the constant current constant voltage charging method, when the constant voltage charging is performed, the constant voltage charging is performed unconditionally for a predetermined time and then the charging with the terminal current is completed. A method for controlling charging of a secondary battery is disclosed.

Japanese Unexamined Patent Publication No. 9-92340

However, in order to prevent insufficient charging, regardless of whether the secondary battery is new or deteriorated, if constant voltage charging for a certain period of time is continued unconditionally as in Patent Document 1, overcharging occurs. Safety issues may arise.

Alternatively, in order to prevent insufficient charging, a charging device that determines the full charge of the secondary battery by using both the value of the charging voltage and the value of the charging current is commercially available. However, even when such a charging device is used, constant voltage charging is continuously performed when either the charging voltage or the charging current cannot detect full charge due to deterioration of the secondary battery. Become. Therefore, safety issues may arise.

As described above, in the constant current / constant voltage charging method, there is a problem that it is difficult to achieve both ensuring safety during charging and preventing insufficient charging.

An object of the present invention is to provide a charge control device capable of preventing insufficient charge while ensuring safety during charging.

The main invention for achieving the above object is a charge control device that controls a charging device that charges a secondary battery by shifting to constant voltage charging after performing constant current charging, and flows through the secondary battery. A control means for controlling the charging current and a charging voltage applied to the terminal of the secondary battery, a storage means for storing the constant voltage charging time, which is the time from the start to the end of the constant voltage charging, and the above-mentioned. In the constant voltage charging, the charging current is a time measuring means for measuring the elapsed time from the start of the constant voltage charging, a first determining means for determining whether or not the elapsed time has reached the constant voltage charging time, and the constant voltage charging. The control means includes a second determination means for determining whether or not a predetermined first current value has been reached and the electromotive force of the secondary battery has reached a predetermined first voltage value, and the control means is charged with the constant current. When the charging voltage reaches the first voltage value from the start of the above, the charging device is controlled to end the constant current charging and start the constant voltage charging, and the first determination means causes the progress. When it is determined that the time has reached the constant voltage charging time, the charging device is controlled to end the constant voltage charging, and the charging current is brought to the first current value by the second determination means. When it reaches and it is determined that the electromotive force has reached the first voltage value, it is determined that the charging current has reached the first current value and the electromotive force has reached the first voltage value. The constant voltage charging time is set as a new constant voltage charging time obtained by subtracting a predetermined shortening time from the elapsed time of time, and after updating the constant voltage charging time stored in the storage means, the charging device is controlled to perform the constant voltage charging time. It is a charge control device characterized by terminating voltage charging.
Other features of the present invention will be clarified by the description of the description and drawings described later.

According to the present invention, it is possible to provide a charge control device capable of preventing insufficient charge while ensuring safety.

It is a block diagram for demonstrating the structure of the charge control device which concerns on 1st Embodiment. It is a graph explaining the transition of the charge current and the charge voltage in the charge method using the charge control device which concerns on 1st Embodiment. It is a graph explaining the transition of the charge current and the electromotive force of the secondary battery in the charge method using the charge control device which concerns on 1st Embodiment. It is a flowchart for demonstrating the charging method using the charge control device which concerns on 1st Embodiment. It is a block diagram for demonstrating the structure of the charge control device which concerns on 2nd Embodiment. It is a graph explaining the transition of the charge current and the electromotive force of the secondary battery in the charge method using the charge control device which concerns on 2nd Embodiment. It is a flowchart for demonstrating the charging method using the charge control device which concerns on 2nd Embodiment.

== 1st Embodiment ==
The configuration of the charge control device 100 according to the present embodiment will be described with reference to an example of a charging method using the charge control device 100. FIG. 1 is a block diagram for explaining the configuration of the charge control device 100 according to the present embodiment. In FIG. 1, the solid line shows the flow of the data signal, and the broken line shows the flow of the control signal. FIG. 2 is a graph illustrating changes in the charging current I and the charging voltage in the charging method using the charge control device 100 according to the present embodiment. FIG. 3 shows changes in the charging current I and the electromotive force V of the secondary battery 300 in the charging method using the charging control device 100 according to the present embodiment. Note that FIG. 2 shows the first of the charging that is repeated a plurality of times for the secondary battery 300. In FIG. 3, among the charges repeated a plurality of times for the secondary battery 300, the first time, the n _11th time, the n _12th time, and the n _13th time (1 <n ₁₁ <n ₁₂ <n ₁₃ ) are shown. Shown. FIG. 4 is a flowchart for explaining a charging method using the charging control device 100 according to the present embodiment.

The charge control device 100 according to the present embodiment controls the charging device 200 that charges the secondary battery 300 by shifting to constant voltage charging after performing constant current charging. The charge control device 100 according to the present embodiment includes a control means 102, a storage means 104, a timekeeping means 106, a first determination means 108, a second determination means 110, and a third determination means 112. .. The charge control device 100 may be an independent device, may be incorporated in the same housing as the charging device 200, or may be incorporated in a device containing the secondary battery 300.

The charging device 200 charges the secondary battery 300 by controlling the charging current I flowing through the secondary battery 300 and the charging voltage applied to the terminals of the secondary battery 300. Specifically, as shown in FIG. 2, the control means 102 of the secondary battery 300 maintains the _{charging current I flowing through the secondary battery 300 at a predetermined current value I 0 in the constant current charging.} It controls the charging voltage, which is the voltage applied to the terminals. Control means 102, when the charging voltage from the start of the constant current charging reaches a first voltage value V _1, and controls the charging device 200, to start the constant-voltage charging to terminate the constant current charging.

Further, the control means 102, in the constant voltage charging, maintaining a charging voltage to the first voltage value V _1. When the control means 102 receives a determination signal described later from the first determination means 108 or the second determination means 110 in the constant voltage charging, the control means 102 controls the charging device 200 to end the constant voltage charging. Then, although the details will be described later, the control means 102 updates the data stored in the storage means 104 as necessary to complete the charging process of the secondary battery 300. More detailed processing performed by the control means 102 will be described later together with FIGS. 3 and 4.

Storing means 104 stores the constant voltage charging time _{T v.} The constant voltage charging time _Tv is an upper limit time from the start to the end of the constant voltage charging by the control means 102. When the constant current charging is completed, the timing means 106 measures the elapsed time t from the start of the constant voltage charging.

First determination means 108 determines the constant voltage charging, whether the clock means 106 the elapsed time counted by t reaches the constant voltage charging time T _v. Specifically, the first determination unit 108 performs the constant voltage charging, the elapsed time t clock means 106 counts, the determination by comparing the constant voltage charging time T _v stored in the storage unit 104 .. First judging means 108, the elapsed time t measured by the time measuring unit 106 have reached the constant voltage charging time T _v, and transmits a determination signal to that effect to the control unit 102.

In the second determination means 110, the charging current I reached a predetermined first current value I ₁ and the electromotive force V of the secondary battery 300 reached the predetermined first voltage value V ₁ described above in the constant voltage charging. Judge whether or not. Specifically, the second determination means 110 sets the charging current I and the electromotive force V of the secondary battery 300 and the preset first current values I ₁ and the first voltage value V _{1 in constant voltage charging.} The determination is made while comparing each. When the second determination means 110 determines that the charging current I has _{reached the first current value I 1} and the electromotive force V of the secondary battery 300 _{has reached the first voltage value V 1} , it controls a determination signal to that effect. It is transmitted to the means 102.

The third determination means 112 determines whether or not the secondary battery 300 is unused before starting charging of the secondary battery 300. When the third determination means 112 determines that the secondary battery 300 is unused, the third determination means 112 transmits a determination signal to that effect to the control means 102.

The processing performed by the control means 102 will be described in more detail with reference to FIGS. 3 and 4. As described above, FIG. 3 shows the first, n _11th , n _12th , and n _13th (1 <n ₁₁ <n ₁₂ <n ₁₃ ) of the charging repeated a plurality of times for the secondary battery 300. It shows four ways. As shown in FIG. 3, as the charging is repeated, the time for the charging current I to reach _{the first current value I 1 becomes shorter from the start of the constant voltage charging due to the deterioration of the secondary battery 300.} In the following, each of these four types of charging will be described.

First, the first charge will be described. The first charge is a charge to the unused secondary battery 300. In this case, before starting charging of the secondary battery 300, the third determination means 112 determines that the secondary battery 300 is unused (S100: Yes in FIG. 4), and controls a determination signal to that effect. It is transmitted to the means 102. Regarding the determination of whether or not the secondary battery 300 is unused, it is determined when the control means 102 detects the replacement of the secondary battery 300, or the secondary battery 300 is an unused battery or a used battery at the time of replacement. It is determined by asking the user to input whether it is a battery.

When the secondary battery 300 is determined to be unused by the third determination unit 112 and a determination signal to that effect is received, the control means 102 sets a predetermined charging time T ₀ in the unused state to a new constant voltage charging time. as T _v, to update the stored constant voltage charging time _{T v} in the storage unit 104 (S102 in FIG. 4). _{In the present embodiment, the charging time Tv} is set to 90 minutes, which is normally required when the unused secondary battery 300 is charged at a constant voltage.

Furthermore, before starting the charging of the secondary battery 300, the control unit 102 reads out from the storage unit 104 the constant voltage charging time _{T v} (S104 in FIG. 4). At the time of charging of the first, constant-voltage charging time T _v stored in the storage unit 104 is as described above 90 seconds.

Next, the control means 102 controls the charging device 200 to perform constant current charging (S106 in FIG. 4). At this time, the control means 102 controls the charging voltage so as to maintain the _{charging current I at a predetermined current value I 0.} At this time, as shown in FIG. 2, the charging voltage increases as the constant current charging continues. Control means 102 continues the constant current charging until the charge voltage reaches the first voltage value V _1.

In constant current charging, when the charging voltage reaches the first voltage value V ₁ , the control means 102 controls the charging device 200 to shift to constant voltage charging (S108 in FIG. 4). At this time, as shown in FIG. 3, the electromotive force V of the secondary battery 300 increases and the charging current I decreases with the constant voltage charging.

When the constant voltage charging time _{T v} from the start of the constant voltage charging has elapsed, the first determination unit 108 determines that the elapsed time t reaches the constant voltage charging time _{T v} (in Figure 4 S110: Yes). Thus, when the elapsed time t by the first judging means 108 is determined to have reached the constant voltage charging time T _v, the control unit 102 controls the charging device 200, and terminates the constant voltage charging The charging of the secondary battery 300 is completed. The first charge in the example shown in FIG. 3 refers to the unused secondary battery 300, and since the unused secondary battery 300 has not deteriorated, the first charge involves constant voltage charging. from the start to the elapse of the constant voltage charging time T _v, the second determination unit 110, the charging current I reaches the first current value I ₁ given, and the electromotive force V of the secondary battery 300 is in a predetermined described above It is not determined that the first voltage value V ₁ has been reached (S112: No in FIG. 4). The above is the process for the first charge (charging of the unused secondary battery 300).

Next, the n _11th charge (n ₁₁ > 1) will be described. In this case, before starting charging, the third determination means 112 determines that the secondary battery 300 is not unused (S100: No in FIG. 4), and transmits a determination signal to that effect to the control means 102. ..

Before starting the charging of the secondary battery 300, the control unit 102 reads out from the storage unit 104 the constant voltage charging time _{T v} (S104 in FIG. 4). At this point, the constant voltage charging time _Tv is the time updated in the first charging process, which is 90 minutes.

Next, the control means 102 performs constant current charging (S106 in FIG. 4) and then shifts to constant voltage charging (S108 in FIG. 4) in the same manner as the first charging.

In this example, from the start of the constant-voltage charged to the constant voltage charging time T _v elapses, electromotive force V reaches the first voltage value V _1, the charging current I to the first current value I ₁ It has not reached (S112: No in FIG. 4). Therefore, similarly to the first charge, the first judging means 108, the elapsed time t is determined to reach the constant voltage charging time T _v (in Figure 4 S110: Yes), the control means determines a signal to that effect Send to 102. Then, the control means 102 controls the charging device 200 to end the constant voltage charging and end the charging of the secondary battery 300. The above is the process for the _{11th charge.}

_{Then, n 12} th charge for _{(n 12>} n ₁₁₎ will be described. Also in this case, before starting charging, the third determination means 112 determines that the secondary battery 300 is not unused (S100: No in FIG. 4), and transmits a determination signal to that effect to the control means 102. do.

Before starting the charging of the secondary battery 300, the control unit 102 reads out from the storage unit 104 the constant voltage charging time _{T v} (S104 in FIG. 4). Even at this point, the constant voltage charging time _Tv is the time updated in the first charging process, which is 90 minutes.

Next, the control means 102 performs constant current charging (S106 in FIG. 4) as in the previous charging, and then shifts to constant voltage charging (S108 in FIG. 4).

In this example, from the start of the constant-voltage charged to the constant voltage charging time T _{v (90} minutes) has passed, the electromotive force V reaches the first voltage value V ₁ at 76 minutes, the charging current I at 80 minutes The first current value I ₁ has been reached. In this way, when it is determined by the second determination means 110 that the charging current I has _{reached the first current value I 1} and the electromotive force V has reached the first voltage value V ₁ (S112: Yes in FIG. 4). In addition, the control means 102 considers the degree of deterioration of the secondary battery 300, and the second determination means 110 sets the charging current I to the first current value I ₁ and the electromotive force V to the first voltage value V ₁ . reached was judged to elapsed time when t time obtained by subtracting the predetermined shortening time ΔT from (80 minutes in this example) as a new constant-voltage charging time T _v, the constant voltage charging time T stored in the storage unit 104 _{Update v} (S114 in FIG. 4). In the present embodiment, the shortened time ΔT is set to 10 minutes. Therefore, the constant voltage charging time T _v stored in the storage unit 104 is updated from 80 minutes elapsed time t 10 minutes short 70 minutes. Then, the control means 102 controls the charging device 200 to end the constant voltage charging and end the charging of the secondary battery 300. The above is the process for the _{12th charge.}

_{Then, n 13} th charge _{(n 13>} n ₁₂₎ will be described. Also in this case, before starting charging, the third determination means 112 determines that the secondary battery 300 is not unused (S100: No in FIG. 4), and transmits a determination signal to that effect to the control means 102. do.

Before starting the charging of the secondary battery 300, the control unit 102 reads out from the storage unit 104 the constant voltage charging time _{T v} (S104 in FIG. 4). At this point, the constant voltage charging time T _v is the time updated in the process of charging the n _12-th, 70 min.

Next, the control means 102 performs constant current charging (S106 in FIG. 4) as in the previous charging, and then shifts to constant voltage charging (S108 in FIG. 4).

In this example, from the start of the constant-voltage charged to the constant voltage charging time T _{v (70} minutes) has elapsed, the electromotive force V reaches the first voltage value V _1, the charging current I is the first current The value I ₁ has not been reached (S112: No in FIG. 4). Accordingly, the first determination unit 108 determines that the elapsed time t reaches the constant voltage charging time _{T v} (in Figure 4 S110: Yes). Then, the control means 102 controls the charging device 200 to end the constant voltage charging and end the charging of the secondary battery 300. The above is the process for the _{13th charge.}

As is clear from the above, the charge control device 100 according to the present embodiment is a charge control device 100 that controls a charging device 200 that charges the secondary battery 300 by shifting to constant voltage charging after performing constant current charging. The control means 102 that controls the charging current flowing through the secondary battery 300 and the charging voltage applied to the terminals of the secondary battery 300, and the constant voltage, which is the time from the start to the end of the constant voltage charging. the determined storage means 104 for storing a charge time T _v, the time counting means 106 for counting the elapsed time t from the start of the constant-voltage charging, whether the elapsed time t reaches the constant voltage charging time T _v 1 Whether or not _{the charging current I has reached a predetermined first current value I 1} and the electromotive force V of the secondary battery 300 _{has reached a predetermined first voltage value V 1} in the determination means 108 and the constant voltage charging. and a second determination unit 110 determines the control means 102, when the charging voltage from the start of the constant current charging reaches a first voltage value V _1, and controls the charging device 200, a constant current charge terminate to start constant-voltage charging, when the elapsed time t by the first judging means 108 is determined to have reached the constant voltage charging time T _v, and controls the charging device 200 terminates the constant voltage charging When it is determined by the second determination means 110 that the charging current I has _{reached the first current value I 1} and the electromotive force V has reached the first voltage value V ₁ , the charging current I becomes the first current value I. ₁ to reach, and as the electromotive force V is the first voltage value V ₁ the time obtained by subtracting the predetermined shortening time from the elapsed time t when it is judged to have reached the new constant-voltage charging time T _v, the storage unit 104 the stored constant voltage charging time T _v with updated controls the charging device 200, and terminates the constant voltage charging.

According to the above configuration, the charge control device 100 _{determines the end of constant voltage charging based on the constant voltage charging time Tv} , the charging current I, and the electromotive force V of the secondary battery 300. Specifically, the charge control unit 100 controls the constant voltage charging, to determine the end of the constant voltage charging to the previous time lapse of the set constant voltage charging time T _v. Here, the constant voltage charging time _Tv is set according to the degree of deterioration of the secondary battery 300. That is, a shorter constant voltage charging time _Tv is applied to the more deteriorated secondary battery 300. Therefore, regardless of whether the secondary battery 300 is new or deteriorated, overcharging can be prevented, so that safety during charging can be ensured. Further, in the constant voltage charging, the charge control device 100 according to the present embodiment has an electromotive force V even if the charging current I reaches a predetermined first current value I _{1 before the constant voltage charging time Tv elapses.} If does not reach the predetermined first voltage value V ₁ , constant voltage charging is continued. That is, in the constant voltage charging, in the constant voltage charging, the charging current I reaches a predetermined first current value I ₁ and the electromotive force V reaches a predetermined first voltage _{before the constant voltage charging time Tv elapses.} When the value V ₁ is reached, it is determined that the constant voltage charging is completed. Therefore, it is possible to prevent the secondary battery 300 from ending charging when the secondary battery 300 still has a capacity that can be charged, so that insufficient charging can be prevented. From the above, according to the charge control device 100 according to the present embodiment, it is possible to prevent insufficient charge while ensuring safety at the time of charging.

Further, in the present embodiment, the third determination means 112 for determining whether or not the secondary battery 300 is unused is further provided, and the control means 102 determines that the secondary battery 300 is unused by the third determination means 112. when the, the predetermined charging time in the unused state as a new constant-voltage charging time T _v, and updates the stored constant voltage charging time T _v in the storage unit 104.

According to the above configuration, it is possible to set the upper limit of the constant voltage charging time for the unused secondary battery 300 T _v advance. Therefore, the safety of the unused secondary battery 300 at the time of charging is improved.

== Second embodiment ==
The configuration of the charge control device 150 according to the present embodiment will be described with reference to an example of a charging method using the charge control device 150. FIG. 5 is a block diagram for explaining the configuration of the charge control device 150 according to the present embodiment. In FIG. 5, the solid line shows the flow of the data signal, and the broken line shows the flow of the control signal. Compared with the charge control device 100 according to the first embodiment, the charge control device 150 according to the present embodiment further includes a fourth determination means 114, and when charging the unused secondary battery 300, the actual charge control device 150 is actually provided. It is different in that it set the constant voltage charging time T _v of the constant-voltage charging was carried out for the first time in.

The fourth determination means 114 determines whether or not _{the charging current I has reached a predetermined second current value I 2 in the constant voltage charging.} Here, the second current value I ₂ may be the same value as, for example, the first current value I _1. More detailed processing performed by the control means 102 will be described later with reference to FIGS. 6 and 7.

The processing performed by the control means 102 will be described in more detail with reference to FIGS. 6 and 7. As described above, FIG. 6 shows the first, n _21st , n _22nd , and n _23rd (1 <n ₂₁ <n ₂₂ <n ₂₃ ) of the charging repeated a plurality of times for the secondary battery 300. It shows four ways. Hereinafter, each of these four types of charging will be described, but the description of the portion overlapping with the first embodiment will be omitted.

In the present embodiment, the processing when it is determined that the secondary battery 300 is unused in the first charging (S200: YES in FIG. 7) is different from that in the first embodiment.

First, the first charge will be described. In this case, before starting charging of the secondary battery 300, the third determination means 112 determines that the secondary battery 300 is unused (S200: YES in FIG. 7), and controls a determination signal to that effect. It is transmitted to the means 102.

Next, the control means 102 controls the charging device 200 to perform constant current charging (S214 in FIG. 7). The control means 102 controls the charging device 200 to end the constant current charging and start the constant voltage charging (S216 in FIG. 7).

In the constant voltage charging, the control means 102 determines the charging current I by the fourth determination means 114 only when the third determination means 112 determines that the secondary battery 300 is unused (S200: YES in FIG. 7). When it is determined that the second current value I ₂ has been reached (S218: YES in FIG. 7), the charging device 200 is controlled to end the constant voltage charging. In this example, the charging current I reaches a predetermined second current value I ₂ 100 minutes after the start of constant current charging. At this time, the control means 102 sets the elapsed time t (100 minutes) when the fourth determination means 114 determines that the second current value I ₂ has been reached as a new constant voltage charging time _Tv , and stores the storage means 104. update the stored constant voltage charging time T _v to (S220 in FIG. 7), to terminate the charging of the secondary battery 300. The above is the process for the first charge (charging of the unused secondary battery 300).

Next, the n _21st charge (n ₂₁ > 1) will be described. In this case, before starting charging, the third determination means 112 determines that the secondary battery 300 is not unused (S200: No in FIG. 7), and transmits a determination signal to that effect to the control means 102. ..

Before starting the charging of the secondary battery 300, the control unit 102 reads out from the storage unit 104 the constant voltage charging time _{T v} (S202 in FIG. 7). At this point, the constant voltage charging time _Tv is the time updated in the first charging process, which is 100 minutes.

Next, the control means 102 performs constant current charging (S204 in FIG. 7) as in the previous charging, and then shifts to constant voltage charging (S206 in FIG. 7).

In this example, from the start of the constant-voltage charged to the constant voltage charging time T _{v (100} minutes) has passed, the electromotive force V reaches the first voltage value V ₁ at 96 minutes, the charging current I is 94 minutes The first current value I ₁ has been reached. In this way, when it is determined by the second determination means 110 that the charging current I has _{reached the first current value I 1} and the electromotive force V has reached the first voltage value V ₁ (S210: Yes in FIG. 7). , the control means 102, second judging means 110, the charging current I reaches the first current value I _1, and the electromotive force V is the elapsed time t when it is judged to have reached the first voltage value V ₁ ( the time obtained by subtracting the predetermined shortening time ΔT from 96 minutes) as the new constant-voltage charging time T _v in this example, to update the stored constant voltage charging time T _v in the storage unit 104 (S212 in FIG. 7). In the present embodiment, the shortened time ΔT is 10 minutes. Therefore, the constant voltage charging time T _v stored in the storage unit 104 is updated to 86 minutes. Then, at this time, the control means 102 controls the charging device 200 to end the constant voltage charging and end the charging of the secondary battery 300. The above is the process for the _{21st charge of n.}

Since the subsequent charging is performed in the same procedure as in the first embodiment, the description thereof will be omitted.

As is clear from the above, the charge control device 150 according to the present embodiment has a third determination means 112 for determining whether or not the secondary battery 300 is unused, and a third determination means 112 for determining whether or not the secondary battery 300 is unused, and a charge current I is a predetermined number in constant voltage charging. 2 The fourth determination means 114 for determining whether or not the current value I ₂ has been reached is further provided, and the control means 102 is a case where the secondary battery 300 is determined to be unused by the third determination means 112. and when the charging voltage from the start of the constant current charging reaches a first voltage value V _1, and controls the charging device 200, to start the constant-voltage charging to terminate the constant current charging, the fourth determination means 114 When it is determined that the charging current I has _{reached a predetermined second current value I 2} , the elapsed time t when it is determined that the second current value I ₂ has been reached is set as a new constant voltage charging time _Tv. , the constant voltage charging time T _v stored in the storage unit 104 with updated controls the charging device 200, and terminates the constant voltage charging.

According to the above configuration, it is possible to charge a sufficient constant voltage charging time T _v relative to an unused secondary battery 300. Therefore, it is possible to prevent the unused secondary battery 300 from being insufficiently charged. Furthermore, the deterioration secondary battery 300 advanced, it is possible to suppress the shortening of the constant voltage charging time T _v to it as much as possible, it is possible to prevent insufficient charging of advanced deterioration secondary battery 300 as much as possible.

The above embodiment is presented as an example and does not limit the scope of the invention. The above configurations can be implemented in appropriate combinations, and various omissions, replacements, and changes can be made without departing from the gist of the invention. The above-described embodiments and modifications thereof are included in the scope and gist of the invention, as well as in the scope of the invention described in the claims and the equivalent scope thereof.

100: Charge control device 150: Charge control device 102: Control means 104: Storage means 106: Timekeeping means 108: First judgment means 110: Second judgment means 112: Third judgment means 114: Fourth judgment means 200: Charging device 300: Secondary battery

Claims (3)

It is a charge control device that controls a charging device that charges a secondary battery by shifting to constant voltage charging after performing constant current charging.
A control means for controlling the charging current flowing through the secondary battery and the charging voltage applied to the terminals of the secondary battery, and
A preset storage means for storing the constant voltage charging time, which is the time from the start to the end of the constant voltage charging,
A timekeeping means for measuring the elapsed time from the start of constant voltage charging, and
A first determination means for determining whether or not the elapsed time has reached the constant voltage charging time,
In the constant voltage charging, the second determination means for determining whether or not the charging current reaches a predetermined first current value and the electromotive force of the secondary battery reaches a predetermined first voltage value is provided. ,
The control means
When the charging voltage reaches the first voltage value from the start of the constant current charging, the charging device is controlled to end the constant current charging and start the constant voltage charging.
When it is determined by the first determination means that the elapsed time has reached the constant voltage charging time, the charging device is controlled to end the constant voltage charging.
When the second determination means determines that the charging current reaches the first current value and the electromotive force reaches the first voltage value, the charging current reaches the first current value. The constant voltage charging time stored in the storage means is defined as a new constant voltage charging time obtained by subtracting a predetermined shortening time from the elapsed time when it is determined that the electromotive force has reached the first voltage value. After updating
A charging control device characterized in that the charging device is controlled to end the constant voltage charging. A third determination means for determining whether or not the secondary battery is unused is further provided.
When the third determination means determines that the secondary battery is unused, the control means
The charge control device according to claim 1, wherein a predetermined charge time in an unused state is set as a new constant voltage charge time, and the constant voltage charge time stored in the storage means is updated. A third determination means for determining whether or not the secondary battery is unused,
In the constant voltage charging, a fourth determination means for determining whether or not the charging current has reached a predetermined second current value is further provided.
The control means is a case where the secondary battery is determined to be unused by the third determination means.
When the charging voltage reaches the first voltage from the start of the constant current charging, the charging device is controlled to end the constant current charging and start the constant voltage charging.
When it is determined by the fourth determination means that the charging current has reached a predetermined second current value, the elapsed time when it is determined that the second current value has been reached is set as a new constant voltage charging time. After updating the constant voltage charging time stored in the storage means,
The charge control device according to claim 1, wherein the charging device is controlled to end the constant voltage charging.

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