Mobile terminal, charging control method, and charging control program

Abstract

To provide a portable terminal capable of stopping charging to a battery when there is trouble in charging to the battery and charging to the battery when there is no trouble when an external power source is connected.SOLUTION: The portable terminal includes a battery therein, and drives an electronic circuit by power from the battery. Further, the mobile terminal is configured to be able to charge the battery with external power. The control means switches between a charging mode for charging the battery with the external power and a non-charging mode for supplying the external power to the electronic circuit without charging the battery. Specifically, when the temperature of the battery or the temperature around the battery is detected by the temperature detection means, the control means switches between the charging mode and the non-charging mode according to the detected temperature.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a method for charging a mobile terminal. [Background technology]

[0002] Generally, when a mobile terminal such as a smartphone is operated while receiving power from an external source, the external power supply is used to charge the battery of the mobile terminal, and the electronic circuits of the mobile terminal operate using power from the battery.

[0003] When a mobile device executes a function with a heavy processing load, such as a navigation function, power consumption increases and the battery temperature rises. In particular, when used in a vehicle environment, direct sunlight or heating can easily cause the battery temperature to rise. In such cases, the mobile device typically activates a function to stop charging the battery to protect it. As a result, even though power is being supplied to the mobile device, the battery may not be charged and the battery's power may be consumed.

[0004] Patent document 1 discloses a mobile terminal that, when an external power source is connected, automatically or by user switching, disconnects the battery pack from the circuit, enabling it to operate solely on the external power source without charging the battery pack. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-10441 Summary of the Invention [Problem to be solved by the invention]

[0006] However, the method of Patent Document 1 has a problem in that charging of the battery does not progress even when the temperature of the battery has not risen.

[0007] The above is one example of the problem that the present invention aims to solve. The present invention aims to provide a mobile terminal that, when connected to an external power source, can stop charging the battery if there is a problem with charging the battery, and can charge the battery if there is no problem. [Means for solving the problem]

[0008] The invention described in the claims is a mobile terminal that is powered by external power, comprising: a battery that supplies power to the electronic circuits of the mobile terminal; a temperature detection unit that detects the temperature of the battery or the area around the battery; and a control unit that, depending on the temperature, switches the mobile terminal to either a charging mode in which the external power is charged to the battery, or a non-charging mode in which the external power is supplied to the electronic circuits without being charged to the battery, wherein, when the mobile terminal is executing an application, the control unit switches the mobile terminal to the non-charging mode regardless of the temperature, depending on information about the application being executed.

[0009] The invention described in the claims is a charging control method executed in a portable terminal capable of supplying external power, which includes an electronic circuit and a battery that supplies power to the electronic circuit, and includes a temperature detection step of detecting the temperature of the battery or the area around the battery, and a control step of switching the portable terminal to either a charging mode in which the external power is charged to the battery, or a non-charging mode in which the external power is supplied to the electronic circuit without being charged to the battery, depending on the temperature, wherein the control step switches the portable terminal to the non-charging mode when the portable terminal is executing an application, regardless of the temperature, depending on information about the application being executed.

[0010] The invention described in the claims is a charging control program executed in a portable terminal capable of supplying external power, which includes a computer, an electronic circuit, and a battery that supplies power to the electronic circuit, and which causes the computer to execute a temperature detection process for detecting the temperature of the battery or the area around the battery, and a control process for switching the portable terminal to either a charging mode in which the external power is charged to the battery, or a non-charging mode in which the external power is supplied to the electronic circuit without being charged to the battery, depending on the temperature, and is characterized in that when the portable terminal is executing an application, the control process switches the portable terminal to the non-charging mode regardless of the temperature, depending on information about the application being executed. [Brief explanation of the drawings]

[0011] [Figure 1] 1 shows the appearance of a mobile terminal according to an embodiment. [Figure 2] 1 shows a schematic configuration for charging a mobile terminal. [Figure 3] An example of a method for charging a battery is shown below. [Figure 4] 10 shows an example of time control of the charging mode and non-charging mode according to the third embodiment. [Figure 5] 1 shows an example of a cradle for mounting a mobile terminal on a vehicle. DETAILED DESCRIPTION OF THE INVENTION

[0012] In a preferred embodiment of the present invention, a portable terminal capable of receiving external power comprises a battery that supplies power to an electronic circuit in the portable terminal body, a temperature detection means that detects the temperature of the battery or the area around the battery, and a control means that controls switching between a charge mode in which the external power is charged to the battery and a non-charge mode in which the external power is supplied to the electronic circuit without charging the battery, and the control means controls switching between the charge mode and the non-charge mode in accordance with the temperature detected by the temperature detection means.

[0013] The portable terminal includes an internal battery and drives an electronic circuit with power from the battery. The portable terminal is also configured to be able to charge the battery with external power. The control means switches between a charge mode in which the battery is charged with external power and a non-charge mode in which external power is supplied to the electronic circuit without charging the battery. Specifically, when the temperature detection means detects the temperature of the battery or the temperature around the battery, the control means switches between the charge mode and the non-charge mode depending on the detected temperature. This makes it possible to determine whether charging is possible, taking into account the battery temperature.

[0014] In one aspect of the portable terminal, the control means switches the portable terminal to the charging mode when the detected temperature is lower than a predetermined temperature, and switches the portable terminal to the non-charging mode when the detected temperature is equal to or higher than the predetermined temperature. In this aspect, the battery is not charged when the detected temperature is high, thereby preventing deterioration of the battery.

[0015] In another aspect of the portable terminal, the control means sets the battery in non-charging mode when the charging rate of the battery is equal to or higher than a predetermined value, regardless of the detected temperature. In this aspect, when the battery is in a charged state to a certain extent, unnecessary repeated charging can be avoided, thereby preventing deterioration of the battery.

[0016] In another aspect of the portable terminal, the control means switches the portable terminal to the non-charging mode when the current consumption of the electronic circuit is equal to or greater than a predetermined value, regardless of the detected temperature. In this aspect, when the power consumption is high, charging is not performed, thereby preventing the battery temperature from rising.

[0017] In another aspect of the portable terminal, the control means calculates a rate of temperature rise of the detected temperature, and switches the portable terminal to a non-charging mode when the rate of temperature rise is equal to or greater than a predetermined value. In this aspect, charging of the battery is stopped before the battery temperature rises close to a critical temperature, thereby reducing damage to the battery.

[0018] In another aspect of the portable terminal, the control means changes the time ratio between the charging mode and the non-charging mode within a unit time in accordance with the detected temperature. In this aspect, the time ratio for charging the battery is controlled in accordance with the detected temperature, so that charging can be performed at an appropriate time allocation in accordance with the battery temperature.

[0019] In another aspect of the portable terminal, the output control means executes the switching when the portable terminal is mounted on a mobile object. Normally, when the portable terminal is mounted on a mobile object such as a vehicle, the battery temperature is particularly likely to rise due to direct sunlight. Therefore, in this aspect, when the portable terminal is mounted on a mobile object, the output control means controls the charging of the battery based on the battery temperature.

[0020] In another preferred embodiment of the present invention, a charge control method executed in a portable terminal capable of supplying external power, the portable terminal including an electronic circuit and a battery for supplying power to the electronic circuit, comprises a temperature detection step of detecting a temperature of the battery or an area around the battery, and a control step of controlling switching between a charge mode in which the external power is charged to the battery and a non-charge mode in which the external power is supplied to the electronic circuit without charging the battery, the control step controlling switching between the charge mode and the non-charge mode in accordance with the temperature detected in the temperature detection step. This charge control method also makes it possible to determine whether charging is possible, taking the battery temperature into consideration.

[0021] In another preferred embodiment of the present invention, a portable terminal capable of receiving external power includes a computer, an electronic circuit, and a battery for supplying power to the electronic circuit. A charge control program executed by the computer includes a temperature detection step of detecting the temperature of the battery or the area around the battery, and a control step of controlling switching between a charge mode in which the battery is charged with the external power and a non-charge mode in which the battery is not charged but the external power is supplied to the electronic circuit. The control step controls switching between the charge mode and the non-charge mode in accordance with the temperature detected by the temperature detection step. By executing this charge control program, it is possible to determine whether charging is possible, taking into account the battery temperature. The charge control program can be stored and accessed on a storage medium. [Example]

[0022] Preferred embodiments of the present invention will now be described with reference to the drawings. [First Example] Fig. 1 shows an example of a mobile terminal according to an embodiment. The mobile terminal 100 may be, for example, a smartphone. Fig. 2 shows a configuration related to charging the mobile terminal 100. In Fig. 2, power supply lines are indicated by solid lines, and control signal lines are indicated by dashed lines.

[0023] As shown in the figure, the mobile terminal 100 is connected to an external power supply device 3. The external power supply device 3 supplies a stabilized voltage, for example, 5V DC, to the mobile terminal 100 from a power source such as a vehicle battery, a USB terminal of a PC, or a commercial AC power source. The external power supply device 3 has a connector at the end of a cable that is detachable from an external connector of the mobile terminal 100. The connector of the external power supply device 3 is, for example, a cigarette lighter charger for supplying power from a vehicle battery, a USB terminal for supplying power from a PC, or an AC adapter for supplying power from a commercial AC power source.

[0024] The mobile terminal 100 includes a battery 5 and an electronic circuit 10. The battery 5 is, for example, a lithium ion battery, a nickel-metal hydride battery, etc. The battery 5 is detachable from the mobile terminal 100 and has an electrical contact with the mobile terminal 100.

[0025] The electronic circuit 10 is a circuit provided inside the mobile terminal 100. The electronic circuit 10 includes a charging unit 11, a voltage conversion unit 12, a switching control unit 13, a switch 14, a temperature detection unit 15, and a driven circuit 16. The electronic circuit 10 operates by receiving power from the battery 5 when no external power is being supplied.

[0026] Driven circuit 16 is a circuit provided to perform the original operation of mobile terminal 10, and specifically includes a CPU, memory, display device, etc. On the other hand, the parts other than driven circuit 16, i.e., charging unit 11, voltage conversion unit 12, switching control unit 13, switch 14, and temperature detection unit 15, are parts that operate to control charging of the battery according to this embodiment.

[0027] The charging unit 11 outputs a charging current for the battery 5 based on the power supplied from the external power supply device 3. The output terminal of the charging unit 11 is connected to the terminal of the battery 5 and the input terminal T1 of the switch 14.

[0028] FIG. 3 shows an example of a charging method for battery 5. In FIG. 3, graph 31 shows the change in charging voltage over time, and graph 32 shows the change in charging current over time. When the charging voltage of battery 5 is below a predetermined value, charging unit 11 outputs a charging current while applying an output limit to the current so that the charging current to battery 5 does not exceed a predetermined current value I1. As a result, the charging voltage of battery 5 gradually increases as shown in graph 31. When the charging voltage of battery 5 reaches a predetermined voltage value V1 at time t1, charging unit 11 continues charging while maintaining the predetermined voltage value V1. Note that in the case of a lithium-ion battery, the predetermined voltage value V1 is set to, for example, 4.0 V. As a result, the charging current gradually decreases as shown in graph 32. Then, charging unit 11 terminates charging when the charging current becomes equal to or less than a predetermined current value I2. As shown in FIG. 3, constant current charging is performed from time 0 to t1, and constant voltage charging is performed from time t1 to t2.

[0029] The voltage conversion unit 12 converts the voltage supplied from the external power supply device 3 to a voltage close to the rated voltage of the battery 5, and outputs the voltage to the input terminal T2 of the switch 14. Note that the rated voltage for a lithium ion battery is, for example, 4.0 V.

[0030] Switch 14 is configured by a semiconductor switch or the like, and switches the current supply path to driven circuit 16 between the battery side and the voltage conversion unit side. Specifically, switch 14 selects one of input terminals T1 and T2, and supplies power from output terminal To to driven circuit 16. In reality, a power supply line is shared within electronic circuit 10, and the power supplied to driven circuit 16 is also supplied to charging unit 11, power conversion unit 12, switching control unit 13, switch 14, and temperature detection unit 15. In other words, the entire electronic circuit 10 operates on the power supplied from switch 14.

[0031] Temperature detection unit 15 detects the temperature of battery 5 or the temperature around battery 5, and supplies the detected temperature as a control signal S15 to switching control unit 13. Temperature detection unit 15 is disposed in a position in contact with or close to battery 5 inside the case of mobile terminal 100. Note that if battery 5 itself has a temperature detection means such as a thermistor built in and is configured to output the detected temperature via the contacts of battery 5, the detected temperature output from battery 5 can be supplied to switching control unit 13. In this case, temperature detection unit 15 is not necessary.

[0032] Switching control unit 13 controls switch 14 based on the detected temperature of battery 5 supplied from temperature detection unit 15, and switches the power supply path to driven circuit 16. Switching control unit 13 sends a control signal S11 to turn on / off the operation of charging unit 11, and sends a control signal S12 to turn on / off the operation of voltage conversion unit 12. Switching control unit 13 also sends a control signal S14 to control the switching of switch 14.

[0033] Specifically, when the detected temperature of battery 5 is below a predetermined value, switching control unit 13 operates charging unit 11 to charge battery 5, stops voltage conversion unit 12, and switches switch 14 to the input terminal T1 side. This causes battery 5 to be charged with power from external power supply device 3. This mode is called "charging mode." In charging mode, charging power from battery 5 is supplied to driven circuit 16 via switch 14, so that the entire electronic circuit 10 operates on the charging power from battery 5.

[0034] On the other hand, when the detected temperature of battery 5 is equal to or higher than the predetermined value, switching control unit 13 stops charging unit 11 to stop charging battery 5, and also operates voltage conversion unit 12 to switch switch 14 to input terminal T2. As a result, battery 5 is not charged, and power from external power supply device 3 is supplied to driven circuit 16. This mode is called the "non-charging mode." In the non-charging mode, power from external power supply device 3 is supplied to driven circuit 16 via switch 14, so that the entire electronic circuit 10 operates on power from external power supply device 3.

[0035] As described above, in this embodiment, when the temperature of the battery 5 is high, the non-charge mode is set and the battery 5 is not charged, and when the temperature of the battery 5 is low, the charge mode is set and the battery 5 is charged. Therefore, the battery 5 can be charged efficiently within a range that does not cause any damage to the battery 5.

[0036] (Variation 1) In addition to the control of the above embodiment, when the charging rate of the battery 5 is equal to or higher than a predetermined value (e.g., 80% or higher), the mobile terminal 100 may be placed in a non-charging mode regardless of the temperature of the battery 5. This makes it possible to prevent unnecessary repeated charging of the battery 5 and extend the battery life. The charging rate of the battery 5 may be determined based on the charging current value of the battery 5. For example, in the example of graph 32 in FIG. 3, the charging rate is 100% when the charging current of the battery 5 is a predetermined current value I2, so a charging current value corresponding to a charging rate of 80% may be determined in advance, and the charging rate may be determined to be 80% when the charging current reaches that charging current value.

[0037] (Variation 2) In addition to the control of the above embodiment, the mobile terminal 100 may be placed in a non-charging mode when the current consumption of the electronic circuit 10 is equal to or greater than a predetermined value, regardless of the temperature of the battery 5. For example, when the mobile terminal 100 is running an application that consumes a lot of power, such as a navigation application, charging the battery 5 may not proceed due to the high power consumption. In such a case, the temperature of the battery 5 may rise unnecessarily, shortening the life of the battery 5. Therefore, it is preferable to operate the mobile terminal 100 using power from the external power supply device 3 without charging the battery 5.

[0038] To detect the current consumption, the mobile terminal 100 may be provided with a current measuring means for detecting the current consumed by the electronic circuit 10. Alternatively, if a standard value of current consumption is set for each application, a reference table of standard values ​​of current consumption may be referenced to predict the current consumption value corresponding to the application while the application is running.

[0039] [Second Example] In the first embodiment, switching between the charge mode and the non-charge mode is performed based on the temperature of the battery 5. Alternatively, switching between the charge mode and the non-charge mode may be performed based on the rate of temperature rise of the battery 5. By checking the rate of temperature rise, charging of the battery 5 can be stopped before the temperature of the battery 5 actually rises close to the limit temperature, thereby reducing damage to the battery 5. Specifically, the rate of temperature rise can be calculated as the change over time in the temperature detected by the temperature detection unit 15, and when this rate exceeds a predetermined rate of temperature rise, switching from the charge mode to the non-charge mode can be performed.

[0040] [Third Example] Instead of the control in the first embodiment, the time ratio between the charge mode and the non-charge mode within a unit time may be changed according to the temperature of the battery 5. For example, the temperature of the battery 5 is classified into several temperature ranges, and the time ratio between the charge mode and the non-charge mode is controlled for each temperature range.

[0041] FIG. 4 shows an example of the time ratio in the third embodiment. In this example, the temperature of the battery 5 is classified into four temperature ranges, and the time ratio between the charging mode and the non-charging mode is set for each temperature range. For example, when the temperature of the battery 5 is below 35°C, the battery 5 is charged for the entire time; when the temperature is between 35°C and 40°C, the charging mode time is set to 70%; when the temperature is between 40°C and 45°C, the charging mode time is set to 30%; and when the temperature is 45°C or higher, the non-charging mode is set for the entire time. This allows the charging of the battery 5 to proceed while mitigating the temperature rise of the battery 5.

[0042] [Fourth Example] In the first embodiment, the control of the first embodiment is performed in all environments. Alternatively, the control of the first embodiment may be performed only while the mobile terminal 100 is mounted on a vehicle. That is, when the mobile terminal 100 is mounted on a vehicle, the charging mode and the non-charging mode are switched based on the temperature of the battery 5, as in the first embodiment. On the other hand, when the mobile terminal 100 is not mounted on a vehicle, the charging mode is basically set, and the battery 5 is charged.

[0043] FIG. 5 shows an example of a cradle used when mounting the mobile terminal 100 in a vehicle in this embodiment. The cradle 200 is attached to the dashboard, windshield, or the like of the vehicle, and holds the mobile terminal 100 by means of a base 214 and a pair of arms 215. An NFC (Near Field Communication) tag 210 is attached to the cradle 200. For example, a unique character string is written in the NFC tag 210. When the mobile terminal 100 is attached to the cradle 200, the mobile terminal 100 reads the character string from the NFC tag and determines that the mobile terminal 100 is mounted in the vehicle (used inside the vehicle). In all other cases, the mobile terminal 100 is determined not to be mounted in the vehicle.

[0044] When the mobile terminal 100 is installed in a vehicle using an in-vehicle cradle, the mobile terminal 100 is usually installed near the dashboard where it is exposed to direct sunlight. In such a situation, the battery temperature is likely to rise. Therefore, by performing the control of the first embodiment, it is possible to charge the battery while preventing the battery temperature from rising. [Explanation of symbols]

[0045] 3 External power supply 5 Battery 10 Electronic circuit 11 Live parts 12 Voltage conversion section 13 Switching control section 14 Switch 15 Temperature detection unit 16 Driven Circuit 100 Terminal Device 200 Cradle

Claims

1. A mobile terminal that is powered by external power, a battery for supplying power to the electronic circuitry of the mobile terminal; a temperature detection unit that detects the temperature of the battery or the surrounding area of ​​the battery; a control unit that switches the portable terminal to either a charging mode in which the external power is charged to the battery or a non-charging mode in which the external power is supplied to the electronic circuit without being charged to the battery, depending on the temperature; Equipped with The control unit, when the mobile terminal is running an application, places the mobile terminal in the non-charging mode regardless of the temperature, depending on information about the running application.

2. The mobile terminal according to claim 1 , wherein the control unit switches the mobile terminal to the non-charging mode regardless of the temperature when the running application is a predetermined application that consumes a large amount of current.

3. The mobile terminal according to claim 1, characterized in that the control unit obtains current consumption information corresponding to the running application as information about the running application from a table showing information about current consumption for each application, and if the current consumption information exceeds a predetermined value, switches the mobile terminal to the non-charging mode regardless of the temperature.

4. The mobile terminal according to claim 3 , wherein the control unit switches the mobile terminal to the non-charging mode when an application whose current consumption exceeds a predetermined threshold is running based on the current consumption information.

5. 5. The mobile terminal according to claim 1, wherein the control unit puts the mobile terminal into the non-charging mode when the remaining charge of the battery is equal to or greater than a predetermined value.

6. A charging control method executed in a portable terminal that is capable of receiving external power, the portable terminal including an electronic circuit and a battery that supplies power to the electronic circuit, the method comprising: a temperature detection step of detecting a temperature of the battery or a temperature around the battery; a control step of switching the portable terminal to either a charging mode in which the external power is charged to the battery or a non-charging mode in which the external power is supplied to the electronic circuit without being charged to the battery, according to the temperature; Equipped with A charging control method characterized in that the control step, when the mobile terminal is executing an application, places the mobile terminal in the non-charging mode regardless of the temperature, depending on information about the application being executed.

7. A charging control program executed in a portable terminal capable of receiving external power, the portable terminal comprising: a computer; an electronic circuit; and a battery that supplies power to the electronic circuit, the charging control program comprising: a temperature detection step of detecting a temperature of the battery or a temperature around the battery; a control step of switching the portable terminal to either a charging mode in which the external power is charged to the battery or a non-charging mode in which the external power is supplied to the electronic circuit without being charged to the battery, according to the temperature; causing the computer to execute A charging control program characterized in that the control step, when the mobile terminal is executing an application, places the mobile terminal in the non-charging mode regardless of the temperature, depending on information about the application being executed.

8. A storage medium storing the charge control program according to claim 7.

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