JP5620423B2 - Electronic device and battery charging method for electronic device - Google Patents

Description

  The present invention relates to an electronic device and a battery charging method for the electronic device, and more particularly to an electronic device for extending a cycle life of the battery and a battery charging method for the electronic device.

  In recent years, electronic devices such as notebook computers, portable information processing devices, mobile phones, and portable game systems have been widely used. Usually, a battery (secondary battery) such as a rechargeable lithium ion battery or a nickel metal hydride battery is used for these electronic devices.

  These batteries are normally charged (preliminary charging) to a predetermined voltage (preliminary charging voltage) with a small current with a charging current kept within a predetermined range, and then the charging current is larger than that during preliminary charging. Charge with current (rapid charge).

  By repeatedly charging and discharging these batteries, the full charge capacity (battery capacity when the battery is fully charged) gradually decreases from the initial full charge capacity at the time of factory shipment. The phenomenon of continuous cycle deterioration occurs. Due to the occurrence of cycle deterioration, the battery has a reduced cycle life (period in which repeated charging and discharging is possible). When charging a battery, rapid charging with a relatively large current is a factor that degrades the battery. Further, it is generally well known that the battery deteriorates when left for a long time in a high energy state (for example, a state where the battery is charged to a full charge capacity).

  Patent Document 1 discloses a secondary battery charging device capable of extending the cycle life. The secondary battery charging device disclosed in Patent Literature 1 includes a battery set detection unit, a timer unit, a charging time determination unit, and a charging control unit. The battery set detection unit detects whether the secondary battery is set to or removed from the charging device, and the timer unit receives the detection result of the battery set detection unit and removes the secondary battery from the charging device. Measure the length of time that is in the state. The charging time determination unit determines the charging time when the secondary battery is reset to the charging device based on the time length measured by the timer unit, and the charging control unit determines the charging time determined by the charging time determination unit. Charge the secondary battery over time. As described above, the technique disclosed in Patent Document 1 determines the charging time when the secondary battery is reset in the charging device based on the length of time that the secondary battery is in the state of being removed from the charging device. To do. Therefore, the charging time is determined so that a charge amount sufficient to supplement the decrease in battery capacity while the secondary battery is removed from the charging device is obtained.

JP-A-8-149708

  The charging device for the secondary battery described in Patent Document 1 described above is charged when the secondary battery is reset to the charging device based on the length of time in which the secondary battery is removed from the charging device. Determine the time. Therefore, the charging time is determined so that a charge amount sufficient to supplement the decrease in battery capacity while the secondary battery is removed from the charging device is obtained. For this reason, since the degree of overcharge (charge beyond the planned charge capacity) can be reduced, deterioration of the battery due to overcharge can be suppressed. However, although the secondary battery charging device described in Patent Document 1 described above can suppress deterioration of the battery due to overcharging, it does not avoid rapid charging. Also, no measures are taken to avoid leaving it for a long time in a high energy state. For this reason, the charging device for the secondary battery described in Patent Document 1 described above has a problem that the battery is deteriorated due to rapid charging. In addition, there is a problem that deterioration of the battery that occurs when left in a high energy state for a long time cannot be avoided.

  An object of the present invention is to provide an electronic device and a battery charging method for the electronic device that can solve the above-described problems and can avoid the deterioration of the battery and extend the cycle life of the battery.

  The electronic device of the present invention is an electronic device that is driven by a battery provided in advance and charges the battery when the driving stops, measures the used battery capacity indicating the consumed capacity of the battery used this time, The charging capacity indicating the capacity of the battery to stop charging is determined in proportion to the measured battery capacity to be smaller than a predetermined upper limit value smaller than the full charging capacity, and an instruction for charging the battery is output. And a charging unit that charges the battery up to the determined charging capacity in response to an instruction to charge the battery from the control unit.

  The battery charging method for an electronic device according to the present invention is a battery charging method for an electronic device that is driven by a battery provided in advance and charges the battery when the driving stops, and indicates the consumption capacity of the battery used this time The battery capacity is measured, and the charge capacity indicating the capacity of the battery to stop charging is determined in proportion to the measured battery capacity used so that the battery capacity is less than a predetermined upper limit value smaller than the current full charge capacity. The battery is charged up to the determined charging capacity.

  ADVANTAGE OF THE INVENTION According to this invention, the deterioration of a battery can be avoided, the electronic device which can extend the cycle life of a battery, and the battery charging method of an electronic device can be provided.

It is a figure which shows an example of the electronic device which concerns on the 1st Embodiment of this invention. It is a figure which shows an example of the electronic device which concerns on the 2nd Embodiment of this invention. It is a flowchart which shows an example of the operation | movement of the 2nd Embodiment of this invention. In the electronic device which concerns on the 2nd Embodiment of invention, it is a figure which shows an example of the table which determines charging capacity in proportion to use battery capacity. It is a figure which shows an example which represented the table in FIG. 4 with the graph. The horizontal axis represents the used battery capacity, and the vertical axis represents the next charging capacity. It is a figure which shows an example of the electronic device which concerns on the 3rd Embodiment of this invention. It is a figure which shows an example of the electronic device which concerns on the 4th Embodiment of this invention. It is a flowchart which shows an example of the operation | movement of the 4th Embodiment of this invention.

Next, embodiments of the present invention will be described with reference to the drawings.
(First embodiment)
FIG. 1 is a diagram showing an example of an electronic apparatus according to the first embodiment of the present invention.

  FIG. 1 also shows an external power supply 5 (for example, an AC (Alternating Current) adapter) that supplies power to the electronic device 1 when the battery 2 is charged.

  The electronic device 1 according to the present embodiment includes a battery 2, a control management unit 3, and a charging unit 4.

  The electronic device 1 is, for example, a notebook computer, a portable information processing device, a mobile phone, a portable game system, or the like. Normal functions of these devices (for example, a telephone function in the case of a mobile phone) are executed when the power switch of the electronic device 1 is ON. On the other hand, the control management unit 3 of the electronic device 1 according to the present embodiment is always operated by the battery 2 or the external power source 5 regardless of ON / OFF of the power switch of the electronic device 1. The charging unit 4 charges the battery 2 with the external power source 5.

  When the electronic device 1 stops driving (the power switch of the electronic device 1 is turned off) and the external power source 5 is connected to the electronic device 1, the charging unit 4 charges the battery 2 with the power of the external power source 5. To do.

  The battery 2 is a secondary battery such as a lithium ion battery, for example. The battery 2 is shipped after charging a rated value (for example, 5000 mAh (milliampere hour)) at a factory or the like at the time of manufacture. Therefore, the battery 2 is charged to the initial full charge capacity (battery capacity when the battery 2 is fully charged) when it is used for the first time.

  The control management unit 3 measures the used battery capacity indicating the consumed capacity (mAh) of the battery 2 used this time. That is, the control management unit 3 determines the capacity consumed by the battery 2 during the period (h (hour)) in which the electronic device 1 is currently driven by the battery 2 (the power switch of the electronic device 1 is ON), for example, the battery 2. Measured by integrating the current value (mA (milliampere)) flowing out from the. Based on the current driving period (h) of the electronic device 1 and the integrated value (mA) of the measured current value, the used battery capacity (mAh) indicating the capacity of the battery 2 used this time is calculated. Then, the control management unit 3 stops charging in proportion to the measured used battery capacity so as to be equal to or less than a predetermined upper limit value (for example, 70% of the full charge capacity) smaller than the current full charge capacity. The charging capacity indicating the capacity of the battery 2 to be determined is determined.

  The control management unit 3 monitors the charge / discharge current to the battery 2 from the initial use of the battery 2, and adjusts the monitored value to the initial battery capacity (rated value (5000 mAh)) every time it is monitored. Thus, the battery capacity is updated to calculate the current battery capacity, and this is stored in a memory (not shown).

  Then, the control management unit 3 detects the connection of the external power supply 5, and outputs the difference capacity between the determined charging capacity and the current battery capacity to the charging unit 4 together with an instruction for charging the battery 2.

  The charging unit 4 receives the difference capacity and the instruction for charging the battery 2 from the control management unit 3, and charges the battery 2 to the charge capacity determined by the control management unit 3. That is, the difference capacity is charged.

  Here, the full charge capacity will be described. The battery 2 is charged to an initial full charge capacity, for example, a rated value (5000 mAh) when shipped from the factory. In the fully charged capacity, the battery voltage Vs is, for example, 3.7V. As the electronic device 1 (battery 2) is used, the full charge capacity is updated as follows. That is, the control management unit 3 monitors the battery voltage, and when the battery voltage decreases to a predetermined index (Vi), for example, (Vt + ((Vs−Vt) / 100) × 5), the control management unit 3 satisfies the following condition. Update the charge capacity. Here, / indicates division, x indicates multiplication, and Vt indicates, for example, 2.8V. (The values of Vs and Vt and the predetermined index (Vi) are not limited to those described above, and may be changed as appropriate by the system.) The control management unit 3 determines the battery voltage after the battery 2 is fully charged. Is integrated with the capacity discharged by the battery 2 (the used capacity of the battery 2) while the battery voltage decreases to a predetermined index (Vi). A capacity value (250 mAh) corresponding to 5% of the rated value (5000 mAh) of the battery 2 is added to the accumulated capacity, and this is set as a new full charge capacity (current full charge capacity). For example, when the integrated capacity while decreasing to a predetermined index (Vi) is 4500 mAh, 4500 + 250 = 4750 (mAh) is the new full charge capacity (current full charge capacity).

As described above, according to the first embodiment of the present invention, the control management unit is charged in proportion to the battery capacity to be used so that it is equal to or less than the predetermined upper limit value smaller than the current full charge capacity. And an instruction for charging the battery is output. Then, the charging unit receives an instruction for charging the battery from the control management unit, and charges the battery to the charging capacity determined by the control management unit. Therefore, since the charged battery is charged to a capacity smaller than the current full charge capacity, the battery does not deteriorate even if left for a long time. For this reason, the cycle life of the battery can be extended.
(Second Embodiment)
FIG. 2 is a diagram illustrating an example of an electronic apparatus according to the second embodiment of the present invention.

  FIG. 2 is obtained by adding a battery usage information storage unit 6 to FIG. Other than the control management unit 3 and the battery usage information storage unit 6 are the same as those in the first embodiment of the present invention. Therefore, the difference from the first embodiment will be mainly described.

  The electronic device 1 according to the present embodiment includes a battery 2, a battery usage information storage unit 6, a control management unit 3, and a charging unit 4.

  In the battery usage information storage unit 6, driving time information of the electronic device 1 indicating information on a time during which the user uses the battery 2 is stored as a usage history of the battery 2. The usage history of the battery 2 is the use start time of the battery 2 indicating the time when the electronic device 1 is driven and the use end time of the battery 2 indicating the time when the driving of the electronic device 1 is stopped. A pair. The time when the electronic device 1 is driven is when the power switch of the electronic device 1 is turned on. The time when the driving of the electronic device 1 is stopped is when the power switch of the electronic device 1 is turned off.

  The control management unit 3 stores the driving time information of the electronic device 1 as the usage history of the battery 2 in the battery usage information storage unit 6. That is, when the external power supply 5 is not connected to the electronic device 1, the control management unit 3 stores battery usage information as a usage history of the battery 2 with a set of the usage start time of the battery 2 and the usage end time of the battery 2. Stored in section 6.

  When the control management unit 3 starts charging the battery 2, the control management unit 3 predicts the time when the user uses the battery 2 from the driving time information of the electronic device 1 stored in the battery usage information storage unit 6.

  The control management unit 3 monitors the charge / discharge current to the battery 2 from the initial use of the battery 2, and adjusts the monitored value to the initial battery capacity (rated value (5000 mAh)) every time it is monitored. Thus, the battery capacity is updated to calculate the current battery capacity.

  And the control management part 3 calculates | requires this chargeable capacity | capacitance by subtracting this present battery capacity from the charge capacity which shows the battery capacity which stops the charge determined by the operation | movement demonstrated in the 1st Embodiment of this invention, When the chargeable capacity can be charged by a predetermined low current lower than a relatively large current for rapid charging by the time when the predicted battery 2 is used, the low current is determined as a charging current; When the chargeable capacity cannot be charged by the predicted time when the battery 2 is used, a relatively large current for rapid charging is determined as the charging current.

  Then, the control management unit 3 detects the connection of the external power supply 5, and determines the difference capacity between the determined charging capacity and the current battery capacity, and the determined charging current together with an instruction for charging the battery 2. 4 is output.

  The charging unit 4 receives the difference capacity, the charging current, and the instruction for charging the battery 2 from the control management unit 3, and the battery 2 is charged based on the charging current determined by the control management unit 3 up to the charging capacity determined by the control management unit 3. Charge.

  Thus, according to the second embodiment of the present invention, the control management unit is charged in proportion to the used battery capacity so as to be equal to or less than a predetermined upper limit value smaller than the current full charge capacity. To decide. In addition, when the control management unit predicts the time when the user uses the battery and the chargeable capacity can be charged with a predetermined low current by the time when the predicted battery is used, the low current is charged as the charging current. To decide. Then, the charging unit charges the battery to the charging capacity determined by the control management unit based on the charging current determined by the control management unit in response to an instruction to charge the battery from the control management unit. Therefore, since the charged battery is charged to a capacity smaller than the current full charge capacity, the battery does not deteriorate even if left for a long time. For this reason, the cycle life of the battery can be extended. In addition, when the chargeable capacity can be charged with a predetermined low current by the time when the predicted battery is used, the battery is charged with the low current. For this reason, since rapid charging which charges with a comparatively large electric current can be avoided, battery deterioration does not advance. For this reason, the cycle life of the battery can be extended.

  Next, the operation of the electronic apparatus according to the second embodiment of the present invention will be described in detail with reference to FIGS.

  FIG. 3 is a flowchart showing an example of the operation of the second exemplary embodiment of the present invention.

  FIG. 4 is a diagram illustrating an example of a table for determining the charging capacity in proportion to the used battery capacity in the electronic device according to the second embodiment of the present invention. The next charge capacity (B) is made to correspond to the used battery capacity (A). The numerical value is the capacity when the current full charge capacity is 100%, and the unit is%. For example, when the current full charge capacity is 3500 (mAh), the numerical value 50 indicates 1750 (mAh). The next charge capacity (B) is proportional to the used battery capacity (A) and is set to be equal to or less than a predetermined upper limit (70%) smaller than the current full charge capacity. (C-1) and (D-1) are obtained by correcting the next charge capacity (B) by the degree of deterioration of the battery 2. The degree of deterioration is 1- (current full charge capacity / first full charge capacity at the time of factory shipment, etc.). When the degree of deterioration = 0, it indicates that no deterioration has occurred, and when the degree of deterioration = 0.1 , For example, indicates 10% degradation. (C-1) is a case where the degree of deterioration is 0.1, and the degree of deterioration is corrected by multiplying the next charge capacity (B) by 1.1. (D-1) is a case where the degree of deterioration is 0.2, and the degree of deterioration is corrected by multiplying the next charge capacity (B) by 1.2. Therefore, when the degree of deterioration is N, for example, the degree of deterioration is corrected by multiplying the next charge capacity (B) by 1 + N. And when (C-1) and (D-1) which corrected the deterioration degree of the next charge capacity (B) exceed a predetermined upper limit (70%), the charge capacity was rounded to this upper limit. Those are (C-2) and (D-2).

  FIG. 5 is a diagram showing an example of the table in FIG. 4 represented by a graph. The horizontal axis represents the battery capacity used, and the vertical axis represents the next charge capacity.

  Here, the operation of the electronic apparatus 1 according to the second embodiment of the present invention will be described with reference to FIG.

  When the electronic device 1 is driven by the battery 2 (the power switch of the electronic device 1 is turned on) and then the driving is stopped (the power switch of the electronic device 1 is turned off), the control management unit 3 Detect connection. When the connection of the external power supply 5 is detected, the battery 2 is charged as follows.

  In step S1 of FIG. 3, the control management unit 3 calculates the used battery capacity indicating the consumed capacity (mAh) of the battery 2 used this time as follows.

  That is, the control management unit 3 discharges the capacity consumed by the battery 2 from the battery 2, for example, during the period (h) when the electronic device 1 is driven by the battery 2 (the power switch of the electronic device 1 is turned on) this time. It is measured by integrating the current value (mA). Based on the current driving period (h) of the electronic device 1 and the integrated value (mA) of the measured current value, the used battery capacity (mAh) indicating the capacity of the battery 2 used this time is calculated.

  In step S2 of FIG. 3, the control management unit 3 determines the charge capacity as follows.

  The control management unit 3 has a memory (not shown) and stores the table of FIG. 4 in this memory in advance. The control manager 3 refers to this table and selects the next charge capacity (B) corresponding to the used battery capacity calculated in step S1. The control management unit 3 determines the degree of deterioration (1- (current full charge capacity / first full charge capacity at the time of factory shipment)) at the time of updating the full charge capacity described in the first embodiment of the present invention. Calculated and stored in a memory (not shown). And the control management part 3 corrects a deterioration degree to the next selected charging capacity (B) using this deterioration degree. When the next charge capacity after the deterioration degree correction exceeds a predetermined upper limit value (for example, 70%), the charge capacity is rounded to the upper limit value. For example, when the used battery capacity is 45% and the deterioration degree is 0.2, the next charge capacity (B) is 78%, so it is rounded to 70%. Therefore, in this case, the charging capacity is determined to be 70%. The determined charging capacity is stored in a memory (not shown).

  In step S3 of FIG. 3, the control management unit 3 calculates the required charging time as follows.

  The control management unit 3 subtracts the current battery capacity stored in the memory (not shown) described in the first embodiment of the present invention from the charge capacity stored in step S2 to obtain the chargeable capacity (mAh). Ask and store in this memory. Then, a charging time required for charging this chargeable capacity with a predetermined low current (for example, 1500 mA) lower than a relatively large current (for example, 3000 mA) for rapid charging is obtained. The required charging time is (chargeable capacity (mAh) / predetermined low current (mA)).

  In step S4 of FIG. 3, the control management unit 3 predicts the time when the user uses the battery 2 as follows.

  The control management unit 3 refers to the usage history of the battery 2 stored in the battery usage information storage unit 6, calculates the average value of the usage start times in the time zone closest to the future from the present time, and calculates the average The value is a predicted value of the time when the battery 2 is used. When there is a lot of data of the use start time in the closest time zone, for example, an average value of a maximum of 20 data is obtained. For example, when the current time is 6 o'clock and the closest time zone in which the use start time is stored is in the 8 o'clock range, the average value of the data at the use start time at 8 o'clock is obtained and this is used as the predicted value. .

  In step S5 of FIG. 3, the control management unit 3 determines the current for charging the battery 2 as follows. That is, the control management unit 3 obtains the time after the charging time calculated in Step S3 has elapsed from the present time, and subtracts the time when the user predicted in Step S4 uses the battery 2 from this time. When the subtracted value is 0 or more, the charging current is determined to be a relatively large current for rapid charging. When the subtracted value is less than 0, the charging current is set to be larger than the relatively large current for rapid charging. Decrease the current to a predetermined low current. Then, the control management unit 3 detects the connection of the external power source 5 and uses the difference capacity between the charging capacity determined in step S2 and the current battery capacity and the charging current determined in step S5 to charge the battery 2. Is output to the charging unit 4.

In step S <b> 6 of FIG. 3, the charging unit 4 receives a difference capacity, a charging current, and an instruction for charging the battery 2 from the control management unit 3, and the control management unit 3 determines the charging capacity determined by the control management unit 3. The battery 2 is charged based on the charging current.
(Third embodiment)
FIG. 6 is a diagram illustrating an example of an electronic apparatus according to the third embodiment of the present invention.

  FIG. 6 shows the function of the control management unit 3 shown in FIG. 1 divided into a battery information management unit 8 and a new control unit 7 in the first embodiment of the present invention. Except for 8 and the control unit 7, the second embodiment is the same as the first embodiment of the present invention. Therefore, the difference from the first embodiment will be mainly described. In this case, the battery 2 and the battery information management unit 8 may constitute a battery pack, and the electronic device 1 may be provided with the battery pack. The electronic device 1 including the battery pack is, for example, a notebook computer, a portable information processing device, or the like.

  The electronic device 1 according to the present embodiment includes a battery 2, a battery information management unit 8, a control unit 7, and a charging unit 4.

  The battery information management unit 8 measures the used battery capacity indicating the consumed capacity (mAh) of the battery 2 used this time. That is, the battery information management unit 8 flows out, for example, the capacity consumed by the battery 2 from the battery 2 during the period (h) when the electronic device 1 is currently driven by the battery 2 (the power switch of the electronic device 1 is turned on). The current value (mA) to be measured is integrated. Then, based on the current drive period (h) of the electronic device 1 and the integrated value (mA) of the measured current value, the used battery capacity (mAh) indicating the capacity of the battery 2 used this time is calculated and stored. .

  The control unit 7 charges in proportion to the used battery capacity stored by the battery information management unit 8 so as to be equal to or less than a predetermined upper limit value (for example, 70% of the full charge capacity) smaller than the current full charge capacity. The charging capacity indicating the capacity of the battery 2 to be stopped is determined.

  The battery information management unit 8 monitors the charge / discharge current to the battery 2 from the initial use of the battery 2, calculates the current battery capacity by adding or subtracting the monitored value to the rated value (5000 mAh), and stores it.

  The control unit 7 detects the connection of the external power supply 5 and outputs a difference capacity between the determined charging capacity and the current battery capacity to the charging unit 4 together with an instruction to charge the battery 2.

  The charging unit 4 receives an instruction for charging the differential capacity and the battery 2 from the control unit 7, and charges the battery 2 to the charging capacity determined by the control unit 7. That is, the difference capacity is charged.

  Here, the full charge capacity will be described. The battery 2 is charged to an initial full charge capacity, for example, a rated value (5000 mAh) when shipped from the factory. In the fully charged capacity, the battery voltage Vs is, for example, 3.7V. As the electronic device 1 (battery 2) is used, the full charge capacity is updated as follows. That is, the control unit 7 monitors the battery voltage, and when the battery voltage falls to a predetermined index (Vi), for example, (Vt + ((Vs−Vt) / 100) × 5), the controller 7 is fully charged as follows. Update capacity. Here, / indicates division, x indicates multiplication, and Vt indicates, for example, 2.8V. (The values of Vs and Vt and the predetermined index (Vi) are not limited to those described above, and may be changed as appropriate by the system.) The control management unit 3 determines the battery voltage after the battery 2 is fully charged. Is integrated with the capacity discharged by the battery 2 (the used capacity of the battery 2) while the battery voltage decreases to a predetermined index (Vi). A capacity value (250 mAh) corresponding to 5% of the rated value (5000 mAh) of the battery 2 is added to the accumulated capacity, and this is set as a new full charge capacity (current full charge capacity). Accordingly, since the first full charge capacity is charged at the time of shipment from the factory, the control management unit 3 starts after the battery 2 is charged to a new full charge capacity (current full charge capacity) after the first full charge capacity. Then, the capacity of the discharged battery (the used capacity of the battery 2) is integrated while the battery voltage drops to a predetermined index (Vi). For example, when the integrated capacity while decreasing to a predetermined index (Vi) is 4500 mAh, 4500 + 250 = 4750 (mAh) is the new full charge capacity (current full charge capacity).

As described above, according to the third embodiment of the present invention, the control unit sets the charging capacity in proportion to the used battery capacity so as to be equal to or less than the predetermined upper limit value smaller than the current full charge capacity. Determine and output instructions for charging the battery. Then, the charging unit 4 receives the battery charging instruction from the control unit and charges the battery to the charging capacity determined by the control unit. Therefore, since the charged battery is charged to a capacity smaller than the current full charge capacity, the battery does not deteriorate even if left for a long time. For this reason, the cycle life of the battery can be extended.
(Fourth embodiment)
FIG. 7 is a diagram illustrating an example of an electronic apparatus according to the fourth embodiment of the present invention.

  FIG. 7 shows the function of the control management unit 3 shown in FIG. 2 in the second embodiment of the present invention divided into a battery information management unit 8 and a new control unit 7, and battery usage information. The storage unit 6 is added. That is, the battery usage information storage unit 6 is added to FIG. Also in this case, similarly to the third embodiment, the battery 2 and the battery information management unit 8 may constitute a battery pack, and the electronic device 1 may be provided with the battery pack. The electronic device 1 in this case is, for example, a notebook computer or a portable information processing device.

  Except for the control unit 7 and the battery usage information storage unit 6, it is the same as the third embodiment of the present invention. Therefore, the difference from the operation of the third embodiment will be mainly described.

  The electronic device 1 according to the present embodiment includes a battery 2, a battery information management unit 8, a battery usage information storage unit 6, a control unit 7, and a charging unit 4.

  In the battery usage information storage unit 6, as shown in the second embodiment, the driving time information of the electronic device 1 indicating information on the time when the user uses the battery 2 is stored as the usage history of the battery 2. . The usage history of the battery 2 is the use start time of the battery 2 indicating the time when the electronic device 1 is driven and the use end time of the battery 2 indicating the time when the driving of the electronic device 1 is stopped. A pair.

  When the external power source 5 is not connected to the electronic device 1, the control unit 7 starts using the battery 2 indicating the time when the electronic device 1 is driven from the battery 2, and stops driving the electronic device 1. A pair with the use end time of the battery 2 indicating the time when the battery is used is stored as a use history of the battery 2 (drive time information of the electronic device 1).

  When the control unit 7 starts charging the battery 2, the control unit 7 predicts the time when the user uses the battery 2 from the driving time information of the electronic device 1 stored in the battery usage information storage unit 6.

  Then, the battery information management unit 8 stores the charge capacity determined by the operation described in the third embodiment of the present invention by the operation described in the third embodiment of the present invention. Subtract the current battery capacity to obtain the chargeable capacity. Then, when the chargeable capacity can be charged by the time when the predicted battery 2 is used by a predetermined low current lower than a relatively large current for rapid charging, the low current is determined as the charging current. To do. When the chargeable capacity cannot be charged by the predicted time when the battery 2 is used, a relatively large current for rapid charging is determined as the charging current.

  Then, the control unit 7 detects the connection of the external power source 5, and outputs the difference capacity between the determined charging capacity and the current battery capacity to the charging unit 4 together with an instruction to charge the battery 2.

  The charging unit 4 receives an instruction for charging the differential capacity and the battery 2 from the control unit 7, and charges the battery 2 to the charging capacity determined by the control unit 7 by the charging current determined by the control unit 7.

  As described above, according to the fourth embodiment of the present invention, the control unit sets the charging capacity in proportion to the used battery capacity so as to be equal to or less than the predetermined upper limit value smaller than the current full charge capacity. decide. In addition, when the control unit predicts the time when the user uses the battery and the chargeable capacity can be charged with a predetermined low current by the time when the predicted battery is used, the low current is used as the charging current. decide. Then, the charging unit charges the battery to the charging capacity determined by the control unit based on the charging current determined by the control unit in response to an instruction to charge the battery from the control unit. Therefore, since the charged battery is charged to a capacity smaller than the current full charge capacity, the battery does not deteriorate even if left for a long time. For this reason, the cycle life of the battery can be extended. In addition, when the chargeable capacity can be charged with a predetermined low current by the time when the predicted battery is used, the battery is charged with the low current. For this reason, since rapid charging which charges with a comparatively large electric current can be avoided, battery deterioration does not advance. For this reason, the cycle life of the battery can be extended.

  Next, the operation of the electronic apparatus according to the fourth embodiment of the present invention will be described in detail with reference to FIGS. 4, 5, 7 and 8.

  FIG. 8 is a flowchart showing an example of the operation of the fourth exemplary embodiment of the present invention.

  FIG. 4 is a diagram illustrating an example of a table for determining the charging capacity in proportion to the used battery capacity in the electronic device according to the second embodiment of the present invention.

  FIG. 5 is a diagram showing an example of the table in FIG. 4 represented by a graph. The horizontal axis represents the used battery capacity, and the vertical axis represents the next charging capacity.

  Here, the operation of the electronic apparatus 1 according to the present embodiment will be described with reference to FIG.

  When the electronic device 1 is driven by the battery 2 (the power switch of the electronic device 1 is turned on) and then the driving is stopped (the power switch of the electronic device 1 is turned off), the control unit 7 connects the external power source 5. Is detected. When the connection of the external power supply 5 is detected, the battery 2 is charged as follows.

  In step S1 of FIG. 8, the battery information management unit 8 calculates the used battery capacity as follows. That is, the battery information management unit 8 determines the capacity consumed by the battery 2 during the period (h) when the electronic device 1 is being driven this time (the power switch of the electronic device 1 is ON), for example, the current value flowing out from the battery 2. Measure by integrating (mA). Based on the current driving period (h) of the electronic device 1 and the integrated value (mA) of the measured current value, the used battery capacity (mAh) indicating the capacity of the battery 2 used this time is calculated.

  In step S2 of FIG. 8, the control unit 7 determines the charge capacity as follows.

  The control unit 7 has a memory (not shown) and stores the table of FIG. 4 in this memory in advance. The control unit 7 refers to this table and selects the next charge capacity (B) corresponding to the used battery capacity calculated by the battery information management unit 8 in step S1. The battery information management unit 8 updates the full charge capacity described in the third embodiment of the present invention with the degree of deterioration (1- (current full charge capacity / initial full charge capacity at the time of factory shipment)). Sometimes calculated and stored. Then, the control unit 7 corrects the deterioration level by using the deterioration level stored by the battery information management unit 8 for the next selected charging capacity (B). When the next charge capacity after the deterioration degree correction exceeds a predetermined upper limit value (70%), the charge capacity is rounded to the upper limit value. For example, when the used battery capacity is 45% and the deterioration degree is 0.2, the next charge capacity (B) is 78%, so it is rounded to 70%. Therefore, in this case, the charging capacity is determined to be 70%.

  In step S3 of FIG. 8, the control unit 7 calculates the required charging time as follows.

  The control unit 7 subtracts the current battery capacity stored by the battery information management unit 8 according to the operation described in the third embodiment of the present invention from the charge capacity stored in step S2, and the chargeable capacity (mAh). ) The battery information management unit 8 monitors the charge / discharge current to the battery 2 from the first use of the battery 2 and calculates the current battery capacity. Then, the control unit 7 sets the charging time necessary for charging the chargeable capacity with a predetermined low current (for example, 1500 mA) lower than a relatively large current (for example, 3000 mA) for rapid charging. Ask. The required charging time is (chargeable capacity (mAh) / predetermined low current (mA)).

  In step S4 of FIG. 8, the control unit 7 predicts the time when the user uses the battery 2 as follows.

  The control unit 7 refers to the usage history of the battery 2 stored in the battery usage information storage unit 6, obtains the average value of the usage start time in the closest time zone from the present time to the future, and calculates the obtained average value. The predicted value of the time to use the battery 2 is used. When there is a lot of data of the use start time in the closest time zone, for example, an average value of a maximum of 20 data is obtained. For example, when the current time is 6 o'clock and the nearest time zone in which the use start time is stored is in the 8 o'clock range, the average value of the data of the use start time at 8 o'clock is obtained.

  In step S5 of FIG. 8, the control unit 7 determines the current for charging the battery 2 as follows. That is, the control unit 7 obtains the time after the charging time calculated in step S3 has elapsed from the present time, and subtracts the time when the user predicted in step S4 uses the battery 2 from this time. When the subtracted value is 0 or more, the charging current is determined to be a relatively large current for rapid charging. When the subtracted value is less than 0, the charging current is set to be larger than the relatively large current for rapid charging. Decrease the current to a predetermined low current. Then, the control unit 7 detects the connection of the external power source 5 and uses the difference capacity between the charge capacity determined in step S2 and the current battery capacity and the charge current determined in step S5 to charge the battery 2. It outputs to the charging part 4 with an instruction | indication.

  In step S <b> 6 of FIG. 8, the charging unit 4 receives the difference capacity, the charging current, and the instruction for charging the battery 2 from the control unit 7, and changes the charging current determined by the control unit 7 to the charging capacity determined by the control unit 7. Based on this, the battery 2 is charged.

  Thus, according to the present invention, the control unit determines the charge capacity in proportion to the used battery capacity so as to be equal to or less than the predetermined upper limit value smaller than the current full charge capacity. In addition, the control unit determines the low current as the charging current when the user can charge the battery by an estimated time when the battery is used. For this reason, since the battery after charging is charged to a capacity smaller than the current full charge capacity, the battery does not deteriorate even if left for a long time, so that the cycle life of the battery can be extended. Further, when charging is possible by the time when the predicted battery is used, the battery is charged with a low current. For this reason, since rapid charging which charges with a comparatively large electric current can be avoided, battery deterioration does not advance. For this reason, the cycle life of the battery can be extended.

Part or all of the above-described embodiments can be described as in the following supplementary notes, but is not limited thereto.
(Appendix 1)
It is an electronic device that is driven by a battery provided in advance and charges the battery when driving is stopped,
The used battery capacity indicating the consumed capacity of the battery used this time is measured, and charging is stopped in proportion to the measured used battery capacity so that it is not more than a predetermined upper limit value smaller than the current full charge capacity. A control management unit for determining a charging capacity indicating a capacity of the battery and outputting an instruction for charging the battery;
A charging unit that charges the battery up to the determined charging capacity in response to an instruction to charge the battery from the control management unit;
An electronic device characterized by comprising:
(Appendix 2)
The electronic device according to appendix 1, wherein the used battery capacity is measured by integrating current values flowing out of the battery during a period in which the electronic device is being driven.
(Appendix 3)
A battery usage information storage unit that stores driving time information of the electronic device indicating information on a time when the user uses the battery;
The control management unit stores driving time information of the electronic device in the battery usage information storage unit according to driving of the electronic device, and starts the charging of the stored electronic device when charging of the battery is started. The time when the user uses the battery is predicted from the time information, the current battery capacity calculated in advance is subtracted from the charge capacity indicating the battery capacity at which the determined charging is stopped, and the chargeable capacity is obtained and rapidly charged. When the chargeable capacity can be charged by a predetermined low current lower than a relatively large current for the predicted use time of the battery, the low current is determined as a charging current, and the prediction If the chargeable capacity cannot be charged by the time when the battery is used, a relatively large current for quick charging is determined as a charging current. It outputs an instruction of charge of the battery,
3. The electronic device according to claim 1, wherein the charging unit receives an instruction to charge the battery from the control management unit, and charges the battery to the determined charging capacity by the determined charging current. machine.
(Appendix 4)
The control management unit monitors the charge / discharge current to the battery from the first use of the battery that is charged to a full charge capacity of a predetermined rated value, and monitors this to the full charge capacity of the rated value. The electronic apparatus according to appendix 3, wherein a current battery capacity is calculated by adjusting a value.
(Appendix 5)
The control management unit obtains a charging time required for charging the chargeable capacity at the predetermined low current, and uses the predicted battery from a time after the required charging time elapses from the present time. When the time is subtracted and the subtracted value is 0 or more, the charging current is determined to be a relatively large current for rapid charging, and when the value is less than 0, the charging current is set to the predetermined low current. Decide,
The electronic device according to supplementary note 3 or 4, characterized in that.
(Appendix 6)
The battery use information storage unit stores the use start time of the battery indicating the time when the electronic device is activated as a use history of the battery,
The control management unit obtains an average value of use start times in the closest time zone from the present time to the future based on the use history of the battery stored in the battery use information storage unit, and calculates the obtained average value. The electronic device according to any one of appendices 3 to 5, wherein the electronic device is a predicted value of the time to use the battery.
(Appendix 7)
The electronic device according to appendix 1, wherein the control management unit detects the degree of deterioration of the battery and corrects the determined charging capacity based on the degree of deterioration of the battery.
(Appendix 8)
The electronic device according to claim 7, wherein the control management unit rounds the charge capacity to the upper limit value when the corrected charge capacity exceeds a predetermined upper limit value.
(Appendix 9)
The control management unit
A battery information management unit that measures and stores the used battery capacity indicating the consumed capacity of the battery used this time;
The charging capacity indicating the capacity of the battery to stop charging is determined in proportion to the used battery capacity stored by the battery information management unit so as to be equal to or less than a predetermined upper limit value smaller than the current full charge capacity. A control unit for outputting instructions for charging the battery;
The electronic apparatus according to any one of appendices 1 to 8, characterized by comprising:
(Appendix 10)
The battery information management unit detects and stores the degree of deterioration of the battery;
The electronic device according to appendix 9, wherein the control unit corrects the determined charging capacity based on a deterioration degree of the battery stored in the battery information management unit.
(Appendix 11)
It is a battery charging method of an electronic device that is driven by a battery provided in advance and charges the battery when driving is stopped,
Measure the used battery capacity indicating the consumed capacity of the battery used this time,
Determining the charge capacity indicating the capacity of the battery to stop charging, in proportion to the measured battery capacity used so as to be equal to or less than a predetermined upper limit value smaller than the current full charge capacity;
The battery charging method for an electronic device, wherein the battery is charged up to the determined charging capacity.
(Appendix 12)
The battery charging method for an electronic device according to claim 11, wherein the battery capacity used is measured by integrating current values flowing out of the battery during a period in which the electronic device is being driven.
(Appendix 13)
According to the driving of the electronic device, storing the driving time information of the electronic device indicating information of the time when the user uses the battery,
When starting to charge the battery, predict the time when the user uses the battery from the stored driving time information of the electronic device,
Subtracting the current battery capacity calculated in advance from the charging capacity indicating the battery capacity to stop the determined charging to obtain a chargeable capacity;
Investigate whether the chargeable capacity can be charged by a predetermined low current lower than a relatively large current for rapid charging by the time when the predicted battery is used,
If the checked result is able to charge the chargeable capacity, this low current is determined as the charging current, and if the checked result is not able to charge the chargeable capacity, a relatively large current for rapid charging Determine the charging current,
13. The battery charging method for an electronic device according to appendix 11 or 12, wherein the battery is charged up to the determined charging capacity by the determined charging current.
(Appendix 14)
Monitoring the charge / discharge current to the battery from the first use of the battery being charged to a fully charged capacity of a predetermined rated value;
The battery charging method for an electronic device according to claim 13, wherein the current battery capacity is calculated by adding or subtracting the monitored value to the full charge capacity of the rated value.

DESCRIPTION OF SYMBOLS 1 Electronic device 2 Battery 3 Control management part 4 Charging part 5 External power supply 6 Battery use information storage part 7 Control part 8 Battery information management part

Claims (10)

It is an electronic device that is driven by a battery provided in advance and charges the battery when driving is stopped,
The used battery capacity indicating the consumed capacity of the battery used this time is measured, and charging is stopped in proportion to the measured used battery capacity so that it is not more than a predetermined upper limit value smaller than the current full charge capacity. A control management unit for determining a charging capacity indicating a capacity of the battery and outputting an instruction for charging the battery;
A charging unit that charges the battery up to the determined charging capacity in response to an instruction to charge the battery from the control management unit;
An electronic device characterized by comprising:   The electronic device according to claim 1, wherein the used battery capacity is measured by integrating current values flowing out of the battery during a period in which the electronic device is being driven. A battery usage information storage unit that stores driving time information of the electronic device indicating information on a time when the user uses the battery;
The control management unit stores driving time information of the electronic device in the battery usage information storage unit according to driving of the electronic device, and starts the charging of the stored electronic device when charging of the battery is started. The time when the user uses the battery is predicted from the time information, the current battery capacity calculated in advance is subtracted from the charge capacity indicating the battery capacity at which the determined charging is stopped, and the chargeable capacity is obtained and rapidly charged. the low current low that predetermined than current for said when to time of using the battery predicted to possible charging the chargeable capacity, determines the low current to the charging current and the predicted the If until time of using battery can not charge the chargeable capacity, the determining the current for rapid charging to the charging current, the charging of the battery finger Outputs a,
The said charging part receives the instruction | indication of the charge of the said battery from the said control management part, The said battery is charged to the said determined charging capacity with the determined said charging current, The Claim 1 or 2 characterized by the above-mentioned. Electronics.   The control management unit monitors the charge / discharge current to the battery from the first use of the battery that is charged to a full charge capacity of a predetermined rated value, and monitors this to the full charge capacity of the rated value. 4. The electronic apparatus according to claim 3, wherein the current battery capacity is calculated by adjusting the value. The control management unit obtains a charging time required for charging the chargeable capacity at the predetermined low current, and uses the predicted battery from a time after the required charging time elapses from the present time. time subtracted, if the subtracted value is greater than or equal to 0, determines the current for rapidly charging the charging current, if the value is less than 0, determines the charging current to the low current the predetermined,
The electronic device according to claim 3 or 4, wherein The battery use information storage unit stores the use start time of the battery indicating the time when the electronic device is activated as a use history of the battery,
The control management unit obtains an average value of use start times in the closest time zone from the present time to the future based on the use history of the battery stored in the battery use information storage unit, and calculates the obtained average value. The electronic apparatus according to claim 3, wherein a predicted value of time when the battery is used is used.   The electronic device according to claim 1, wherein the control management unit detects the degree of deterioration of the battery and corrects the determined charging capacity based on the degree of deterioration of the battery.   8. The electronic apparatus according to claim 7, wherein the control management unit rounds the charge capacity to the upper limit value when the corrected charge capacity exceeds a predetermined upper limit value. The control management unit
A battery information management unit that measures and stores the used battery capacity indicating the consumed capacity of the battery used this time;
The charging capacity indicating the capacity of the battery to stop charging is determined in proportion to the used battery capacity stored by the battery information management unit so as to be equal to or less than a predetermined upper limit value smaller than the current full charge capacity. A control unit for outputting instructions for charging the battery;
The electronic apparatus according to claim 1, further comprising: The battery information management unit detects and stores the degree of deterioration of the battery;
The electronic device according to claim 9, wherein the control unit corrects the determined charging capacity based on a degree of deterioration of the battery stored in the battery information management unit.

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