Battery control device and mobile phone battery

Abstract

The present invention relates to a battery control device and a mobile phone battery. The present invention shortens the charging time to a battery. A battery control device (60) is provided with a discharge control section (63) that controls discharge from a battery (52), and a charge control section (65) that controls charging to the battery (52). The discharge control section (63) is configured to be able to at least implement discharge from the battery (52) up to a predetermined lower limit SOC (72) that is higher than a predetermined pre-charge SOC (73). The charge control section (65) is configured to, when the current SOC (70) of the battery (52) is lower than the pre-charge SOC (73), charge at a second charge rate (R2) that is lower than a predetermined first charge rate (R1), and when the current SOC (70) of the battery (52) is equal to or higher than the pre-charge SOC (73), charge at the first charge rate (R1).

Description

Technical Field

[0001] This invention relates to battery control devices and mobile phone batteries. Background Technology

[0002] For example, Patent Document 1 discloses a battery system having multiple battery cells and charging and discharging the battery cells. In the battery system disclosed here, charging of the multiple battery cells includes a balancing charging mode and a normal charging mode, with the normal charging mode performed after the balancing charging mode.

[0003] In the balancing charging mode, for example, when a voltage difference exists among multiple battery cells, pre-charging is performed on all battery cells. Through pre-charging in the balancing charging mode, the voltage difference between the battery cells is reduced, and the voltage values ​​of the battery cells are equalized. In the normal charging mode, the battery cells whose voltage values ​​have been equalized in the balancing charging mode are normally charged. Therefore, differences in the state of charge among the battery cells can be suppressed, and each battery cell is fully charged.

[0004] Patent Document 1: International Publication No. 2014 / 156041

[0005] However, in recent years, the demand for mobile devices such as smartphones has been increasing. If a mobile device's battery runs out, it takes about 15 to 30 minutes to charge it to the power required for continued use, for example, to reach approximately 25% SOC. Mobile devices also utilize portable phone batteries for charging. If a mobile device's battery runs out, it can be charged by connecting it to a power outlet or to a phone battery. This is especially useful when the user needs to be mobile, allowing them to charge their mobile device using a phone battery.

[0006] However, the phone battery may also become depleted. Therefore, given the reduced charging capacity of the mobile terminal and its battery, it is preferable to be able to charge the mobile terminal and battery quickly. For example, applying the balanced charging mode disclosed in Patent Document 1 and the normal charging mode to the phone battery enables charging, but requires charging time. In the case of rapid charging, it is preferable to minimize the charging time required to reach the power needed for continuous use for a certain period of time. Summary of the Invention

[0007] The battery control device proposed herein includes: a discharge control unit for controlling the discharge from the battery; and a charge control unit for controlling the charging of the battery. The discharge control unit is configured to discharge from the battery until the battery reaches a predetermined lower limit SOC that is higher than a predetermined pre-charge SOC. The charge control unit is configured to charge the battery at a second charge rate lower than a predetermined first charge rate when the battery's SOC is lower than the pre-charge SOC, and to charge the battery at a first charge rate when the battery's SOC is higher than the pre-charge SOC.

[0008] According to the battery control device proposed here, when charging the battery, if the battery's SOC is lower than the pre-charge SOC, charging is performed at a relatively low second charging rate; if the SOC becomes higher than the pre-charge SOC, charging is performed at a relatively high first charging rate. Here, the pre-charge SOC is set lower than the lower limit SOC during discharge, so charging based on the relatively low second charging rate ends when the battery's SOC falls below the lower limit SOC. Therefore, the time required for charging based on the relatively low second charging rate can be shortened, thus shortening the total charging time, including charging based on the first charging rate and charging based on the second charging rate.

[0009] It can also be configured such that, based on the battery control device proposed here, the difference between the pre-charge SOC and the lower limit SOC is 5% to 30% of SOC.

[0010] The mobile phone battery proposed herein includes: a casing; a battery disposed within the casing, capable of being charged at a charging rate of 5C or higher; a power supply unit disposed within the casing; and a battery control device connected to the battery and the power supply unit. The battery control device includes: a discharge control unit for controlling the discharge from the battery; and a charging control unit for controlling the charging of the battery. The discharge control unit is configured to discharge the battery until it reaches a predetermined lower limit SOC higher than a predetermined pre-charge SOC. The charging control unit is configured to charge at a second charging rate lower than a predetermined first charging rate when the battery's SOC is lower than the pre-charge SOC, and to charge at a first charging rate when the battery's SOC is higher than the pre-charge SOC.

[0011] It can also be configured such that, based on the mobile phone battery proposed here, the power supply unit includes a wireless power supply device. Attached Figure Description

[0012] Figure 1 This is a block diagram schematically illustrating the charging system involved in the implementation method.

[0013] Figure 2 This is a flowchart showing the sequence of control measures taken by the battery control device to discharge the battery.

[0014] Figure 3 It is a graph showing the current and voltage values ​​during battery discharge.

[0015] Figure 4A This is a flowchart showing the sequence of control measures by the battery control device to charge the battery.

[0016] Figure 4B This is a flowchart showing the sequence of control measures by the battery control device to charge the battery.

[0017] Figure 5 It is a graph showing the current and voltage values ​​during battery charging.

[0018] Figure 6 This is a block diagram schematically illustrating a charging system according to another embodiment.

[0019] Explanation of reference numerals in the attached figures

[0020] 10, 10A…charging system; 20…power supply device; 50…mobile phone battery; 51…casing; 52…battery; 54…power receiving unit; 56…power supply unit; 60…battery control device; 61…storage unit; 63…discharge control unit; 65…charging control unit; 70…current SOC; 71…upper limit SOC; 72…lower limit SOC; 73…precharge SOC. Detailed Implementation

[0021] Hereinafter, an embodiment of the battery control device and mobile phone battery disclosed herein will be described with reference to the accompanying drawings. The embodiment described herein is not intended to specifically limit the invention. Unless otherwise specifically mentioned, the invention is not limited to the embodiment described herein. The drawings are schematically depicted and do not necessarily reflect the actual object. Furthermore, components or parts that perform the same function are appropriately labeled with the same reference numerals, and repeated descriptions are appropriately omitted.

[0022] Figure 1 This is a schematic block diagram illustrating the charging system 10 according to this embodiment. In this embodiment, the battery control device and the mobile phone battery are... Figure 1 The charging system 10 shown is implemented here. First, the structure of the charging system 10 will be described. The charging system 10 includes a power supply device 20, a mobile phone battery 50, and a mobile terminal 80. In the charging system 10, the mobile phone battery 50 is quickly charged from the power supply device 20. Furthermore, the mobile terminal 80 can be charged, for example, using the charged mobile phone battery 50.

[0023] The power supply unit 20, the mobile phone battery 50, and the mobile terminal 80 appropriately include control devices. The control device is a device that controls various processes of each device. The control device can be embodied by a computer driven along a pre-determined program. Specifically, the functions of the control device are processed by the arithmetic unit (also called a processor, CPU (Central Processing Unit), MPU (Micro-processing Unit)) and storage device (memory, hard disk, etc.) of the computer constituting the control device. For example, the structure of the control device can be embodied as a database storing data to be embodied by the computer in a pre-determined form, a data structure, a processing module performing prescribed arithmetic processing according to a pre-determined program, or as part of these. The control devices assembled in each device can also be configured to communicate data with each other and cooperate to perform their functions.

[0024] The power supply device 20 includes a power supply unit 21, a power supply unit 22, and a power supply control device 23. The power supply unit 21 is configured to charge the mobile phone battery 50. For example, the power supply unit 21 can transmit (in other words, supply) power to the mobile phone battery 50, and can be a device capable of supplying power at high output. The power supply unit 21 is, for example, a wireless, i.e., non-contact power supply device. However, the power supply unit 21 can also be a contact-type power supply device.

[0025] The power supply unit 22 is connected to an external power source 30. The power supply unit 22 is a device that receives power from the external power source 30 and supplies power to external devices such as the mobile phone battery 50 and mobile terminal 80 via the power supply unit 21. The external power source 30 can also be a 100V or 200V AC power source. The power supply unit 22 can also include an AC / DC converter.

[0026] The power supply control device 23 is electrically connected to the power supply unit 21 and the power supply unit 22. The power supply control device 23 controls the power supplied from the power supply unit 21 to the mobile phone battery 50. In addition, the power supply control device 23 controls the acceptance of power from the external power source 30 to the power supply unit 22.

[0027] The mobile phone battery 50 includes a housing 51, a battery 52, a power receiving unit 54, a power supply unit 56, and a battery control device 60. The housing 51 has a defined space inside. The battery 52, the power receiving unit 54, the power supply unit 56, and the battery control device 60 are disposed within the housing 51.

[0028] Battery 52 is designed to be fast-charging and is composed of a high-output battery. For example, battery 52 can be appropriately adapted to the battery technology used in hybrid vehicles. This battery 52 can be charged at a charging rate of 5C or higher (e.g., 8C or higher, 10C or higher). Battery 52 is designed to minimize degradation even when charging at a current value of 5C or higher.

[0029] In this specification, the current required to fully charge or discharge the theoretical capacity of battery 52 within one hour is defined as 1C. For example, if the capacity of battery 52 is 2Ah, then 1C is 2A. 3C is equivalent to three times the current value of 1C, and in the above example, it refers to the current value required to fully charge or discharge the theoretical capacity within 20 minutes. For example, with a charging rate of 5C for battery 52, approximately 15% of the theoretical capacity can be charged in about 3 minutes. Approximately 25% of the theoretical capacity can be charged in about 5 minutes. In the future, if battery technology for the drive power supply of hybrid vehicles is further applied, even shorter charging times can be achieved with higher charging current values. Therefore, it is expected that the required power can be charged to battery 52 in a time ranging from a few seconds to tens of seconds.

[0030] Furthermore, although the illustrations are omitted, the mobile phone battery 50 according to this embodiment can also include a high-capacity battery in addition to the high-output battery 52. ​​The high-capacity battery, for example, allows charging and discharging at a charging rate of approximately 1C to 3C. The high-capacity battery, for example, has an energy density of approximately 400Wh / L to 800Wh / L.

[0031] In this embodiment, the battery 52 includes a battery pack 53. The battery 52 may have one battery pack 53, but here there are multiple battery packs 53. The number of battery packs 53 is not particularly limited. When there are multiple battery packs 53, the multiple battery packs 53 can be connected in series or in parallel.

[0032] The power receiving unit 54 is powered by the power supply unit 21 of the power supply device 20. The power receiving unit 54 can receive power at high output. Here, the power receiving unit 54 includes a wireless power receiving device. The wireless power receiving device is powered by the power supply unit 21 of the power supply device 20, for example, in a contactless power supply (wireless power supply) manner. In the contactless power supply method, electromagnetic induction, magnetic field resonance, electric field coupling, radio wave reception, etc., can be used. However, the power receiving unit 54 can also be a contact-type power receiving device.

[0033] The power transmission unit 56 is configured to charge the mobile terminal 80 and is capable of transmitting power. The power transmission unit 56 includes a wireless power transmission device. For example, the wireless power transmission device supplies power to the terminal receiving unit 84 of the mobile terminal 80 (described later) in a contactless power supply (wireless power supply) manner. However, the power transmission unit 56 may also be a contact-type power transmission device. In this embodiment, regarding the power supply from the power transmission unit 56 to the mobile terminal 80, for example, the current value can be controlled to supply power at a current value that minimizes the degradation of the built-in battery 82 of the mobile terminal 80 (described later).

[0034] With this type of mobile phone battery 50, the required power can be obtained from the power supply device 20 in a short time through fast charging. Therefore, users do not need to wait for a long time to charge in places where the power supply device 20 is installed. Moreover, power can be slowly supplied from the mobile phone battery 50 to the mobile terminal 80 with a current value that determines the degree to which the built-in battery 82 of the mobile terminal 80 does not deteriorate. For example, after charging the mobile phone battery 50 from the power supply device 20, the mobile terminal 80 can be charged from the mobile phone battery 50.

[0035] The battery control device 60 controls the charging and discharging of the battery 52. ​​Although not shown in the figures, the battery control device 60 includes a charge / discharge control circuit for controlling the charging and discharging of the battery 52, and a battery protection circuit for protecting the battery 52 from overcharging and over-discharging. The battery control device 60 is electrically connected to the battery 52, the power receiving unit 54, and the power supply unit 56. The battery control device 60 includes a storage unit 61, a discharge control unit 63, and a charging control unit 65. Details of the storage unit 61, the discharge control unit 63, and the charging control unit 65 will be described later.

[0036] The mobile terminal 80 can be, for example, a smartphone, mobile phone, tablet computer, or mobile PC. The mobile terminal 80 includes a built-in battery 82, a terminal power receiving unit 84, and a terminal control device 86.

[0037] The built-in battery 82 is a battery that supplies power to the mobile terminal 80. The built-in battery 82 only needs to have the charging capacity required for continuous use of the mobile terminal 80 for a certain period of time.

[0038] The terminal power receiving unit 84 is electrically connected to the mobile phone battery 50. The terminal power receiving unit 84 includes a wireless power receiving device as described above. However, the terminal power receiving unit 84 can also be a contact-type power receiving device. Here, power is supplied from the power supply unit 56 of the mobile phone battery 50 to the terminal power receiving unit 84 to charge the built-in battery 82.

[0039] The terminal control device 86 is electrically connected to the built-in battery 82 and the terminal power receiving unit 84. The terminal control device 86 controls the power supplied through the terminal power receiving unit 84 and controls the charging of the built-in battery 82. Here, the terminal control device 86 has, for example, a charging control circuit that controls the charging of the built-in battery 82, and a battery protection circuit that protects the built-in battery 82 in a way that prevents overcharging.

[0040] Next, the control of charging and discharging of battery 52 by battery control device 60 in mobile phone battery 50 will be explained. Hereinafter, charging and discharging of battery 52 refers to charging and discharging of multiple battery packs 53, respectively.

[0041] In this embodiment, the charging and discharging of battery 52 is controlled based on the state of charge (hereinafter referred to as SOC). Here, the current SOC of battery 52 is referred to as the current SOC.

[0042] Figure 2 This is a flowchart showing the sequence of control of the discharge from battery 52 by battery control device 60. Figure 3 This is a graph showing the current and voltage values ​​during the discharge of battery 52. ​​Next, along with... Figure 2 The flowchart illustrates the control of the battery control device 60 over the discharge from the battery 52. ​​In this embodiment, as... Figure 1 As shown, the discharge of battery 52 occurs, for example, when the power supply unit 56 of mobile phone battery 50 is electrically connected to the terminal power receiving unit 84 of mobile terminal 80 and when mobile terminal 80 is being charged from mobile phone battery 50. The discharge from battery 52 is caused by… Figure 1 The discharge control unit 63 of the battery control device 60 implements this. The discharge control unit 63 controls the discharge from the battery 52.

[0043] In this embodiment, such as Figure 3 As shown, battery 52 is configured with a predetermined upper limit SOC 71 and a predetermined lower limit SOC 72 that is lower than the upper limit SOC 71. The upper limit SOC 71 and the lower limit SOC 72 are stored in... Figure 1 The storage unit 61 shown. The specific values ​​of the upper limit SOC 71 and the lower limit SOC 72 are not particularly limited. The upper limit SOC 71 is, for example, SOC 80% to SOC 95%, preferably SOC 80% to SOC 90%, and particularly preferably SOC 80% to SOC 85%. The lower limit SOC 72 is, for example, SOC 0% to SOC 15%, preferably SOC 5% to SOC 15%, and particularly preferably SOC 10% to SOC 15%.

[0044] Here, the voltage value of battery 52 corresponding to the upper limit SOC 71 is referred to as the upper limit voltage value V71, and the voltage value of battery 52 corresponding to the lower limit SOC 72 is referred to as the lower limit voltage value V72. In the following description, SOC can be replaced with voltage value. For example, the current SOC 70 (refer to...) Figure 2 The upper limit SOC71 and lower limit SOC72 can be replaced with the current voltage value of battery 52 (hereinafter referred to as the voltage value of battery 52), the upper limit voltage value V71, and the lower limit voltage value V72, respectively.

[0045] Figure 1 The discharge control unit 63 controls the discharge from battery 52 until the current SOC 70 (see reference). Figure 2 The discharge control unit 63 controls the discharge from the battery 52 until the voltage value of the battery 52 is at least reduced to the lower limit SOC 72. In other words, the lower limit SOC 72 is the lower limit value of the current SOC 70 when the battery 52 is discharged by constant current (hereinafter referred to as CC (Constant Current)).

[0046] Here, firstly in Figure 2 In step S101, Figure 1 The discharge control unit 63 determines whether the current SOC 70 of the battery 52 is higher than the lower limit SOC 72. Here, if it is determined that the current SOC 70 is lower than the lower limit SOC 72, the discharge from the battery 52 is stopped and the process ends. Figure 2 The flowchart.

[0047] On the other hand, if it is determined in step S101 that the current SOC 70 of battery 52 is higher than the lower limit SOC 72, the process proceeds to step S103. In step S103, the discharge control unit 63 controls CC discharge. For example, in Figure 3 In the middle, CC discharge begins at time T10.

[0048] Next, in Figure 2 In step S105, during CC discharge, the discharge control unit 63 determines whether the current SOC 70 of the battery 52 is below the lower limit SOC 72. Here, if it is determined that the current SOC 70 is still higher than the lower limit SOC 72, the processing in step S105 is executed again.

[0049] On the other hand, if it is determined in step S105 that the current SOC70 is below the lower limit SOC72, then proceed to step S107. Figure 3 In the middle, at time T11, the current SOC 70 of battery 52 becomes below the lower limit SOC 72. Figure 2In step S107, the discharge control unit 63 controls the battery 52 to discharge at a constant voltage (hereinafter referred to as CV (Constant Voltage)).

[0050] Next, in step S109, during CV discharge, the discharge control unit 63 determines whether the current current value (hereinafter referred to as the current current value) A10 of the battery 52 is below the target current value A11. The target current value A11 is pre-stored in... Figure 1 The storage unit 61 is appropriately configured. Here, if it is determined that the current current value A10 is still higher than the target current value A11, the processing of step S109 is executed again. On the other hand, if it is determined in step S109 that the current current value A10 is lower than the target current value A11, the process proceeds to step S111, and the control of discharging the battery 52 ends. Furthermore, in Figure 3 At time T12, the current value A10 changes to below the target current value A11, ending the discharge from battery 52.

[0051] Figure 4A and Figure 4B This is a flowchart showing the sequence of control by the battery control device 60 to charge the battery 52. Figure 5 This is a graph showing the current and voltage values ​​during the charging of battery 52. ​​Next, along with... Figure 4A and Figure 4B The flowchart illustrates the control of charging battery 52. ​​In this embodiment, as... Figure 1 As shown, charging of battery 52 occurs when the power supply unit 21 of power supply device 20 is electrically connected to the power receiving unit 54 of mobile phone battery 50, and when the mobile phone battery 50 is charged from power supply device 20. Control of charging of battery 52 is implemented by charging control unit 65. Charging control unit 65 controls the charging of battery 52.

[0052] In this embodiment, the charging control unit 65 performs pre-charging and fast charging on the battery 52. ​​Here, as... Figure 5 As shown, a predetermined pre-charge SOC 73 is set in battery 52. ​​The voltage value of battery 52 corresponding to the pre-charge SOC 73 is referred to as the pre-charge voltage value V73. In the following description, when SOC is replaced with voltage value, pre-charge SOC 73 can be replaced with pre-charge voltage value V73. The pre-charge SOC 73 is lower than the lower limit SOC 72 and is pre-stored in... Figure 1Storage unit 61. The pre-charge SOC 73 is, for example, SOC 0% to SOC 15%, preferably SOC 0% to SOC 10%, and particularly preferably SOC 0% to SOC 5%. The difference between the pre-charge SOC 73 and the lower limit SOC 72 is, for example, SOC 5% to SOC 30%, preferably SOC 10% to SOC 30%, and particularly preferably SOC 15% to SOC 30%.

[0053] The charging control unit 65 performs pre-charging until the current SOC 70 becomes the predetermined pre-charged SOC 73, after which fast charging is performed.

[0054] Here, firstly in Figure 4A In step S201, the charging control unit 65 determines whether the current SOC 70 of the battery 52 is higher than the protection SOC 74. Here, the protection SOC 74 refers to the upper limit of the current SOC 70 when the battery 52 is in an over-discharge state. That is, when the current SOC 70 is lower than the protection SOC 74, the battery 52 becomes over-discharged. The protection SOC 74 is a predetermined value that is pre-stored. Figure 1 Storage unit 61. For example... Figure 5 As shown, the protection SOC 74 is lower than the pre-charge SOC 73. The voltage value of the battery 52 corresponding to the protection SOC 74 is referred to as the protection voltage value V74. Hereinafter, when SOC is replaced with voltage value, the protection SOC 74 can be replaced with the protection voltage value V74.

[0055] In this embodiment, when in Figure 4A In step S201, if it is determined that the current SOC 70 of battery 52 is below the protection SOC 74, it is preferable not to charge battery 52. ​​Therefore, when the current SOC 70 is below the protection SOC 74, charging of battery 52 is not performed and the process ends. Figure 4A and Figure 4B The flowchart.

[0056] On the other hand, if it is determined in step S201 that the current SOC70 is higher than the protection SOC74, the next step is to... Figure 4A Step S203. In step S203, the charging control unit 65 determines whether the current SOC 70 of the battery 52 is lower than the pre-charge SOC 73. Here, if it is determined that the current SOC 70 is higher than the pre-charge SOC 73, the determination in step S203 is considered negative. In this case, pre-charging control of the battery 52 is not performed, and the process proceeds to step S203. Figure 4A The fast charging process in step S209.

[0057] On the other hand, if it is determined in step S203 that the current SOC 70 of battery 52 is lower than the precharge SOC 73, then the process proceeds to... Figure 4A Step S205. In step S205, the charging control unit 65 pre-charges the battery 52, thus controlling it to charge at a second charging rate R2 (here, CC charging). Figure 5 At time T20, the current SOC 70 of battery 52 is lower than the pre-charge SOC 73, so pre-charging of battery 52 begins.

[0058] Next, in step S207, during pre-charging, the charging control unit 65 determines whether the current SOC 70 is higher than or equal to the pre-charging SOC 73. Here, if it is determined that the current SOC 70 is lower than the pre-charging SOC 73, the processing in step S207 is executed again, and pre-charging continues.

[0059] On the other hand, if it is determined in step S207 that the current SOC 70 is above the pre-charge SOC 73, then to end the pre-charge, the process proceeds to step S209. In step S209, the charging control unit 65 performs fast charging on the battery 52, thus controlling it to charge at a first charging rate R1 that is higher than the second charging rate R2 in the pre-charge. Here, fast charging is CC charging. Figure 5 At time T21, the current SOC 70 of battery 52 becomes above the pre-charge SOC 73, and therefore fast charging begins.

[0060] Here, the first charging rate R1 in fast charging is, for example, 5C to 20C, preferably 10C to 20C, and more preferably 15C to 20C. The second charging rate R2 in precharging is, for example, 0.05C to 0.5C, preferably 0.1C to 0.5C, and more preferably 0.3C to 0.5C.

[0061] Next, in Figure 4A In step S211, the charging control unit 65 determines whether the current SOC 70 of the battery 52 is lower than the upper limit SOC 71 during fast charging. If the current SOC 70 is higher than the upper limit SOC 71, the battery 52 can be considered to be in an overcharged state. Here, if it is determined that the current SOC 70 is lower than the upper limit SOC 71, the process proceeds to step S213.

[0062] In step S213, the charging control unit 65 determines whether the current charging capacity C10, which is the current charging capacity of the battery 52, is less than the target charging capacity C11. The target charging capacity C11 is the charging capacity of the battery 52 that is to be obtained through charging, and is set for each battery 52. ​​The target charging capacity C11 is pre-stored in... Figure 1 Storage unit 61. Here, if it is determined that the current charging capacity C10 of battery 52 is less than the target charging capacity C11, the process returns to step S211 and continues fast charging.

[0063] On the other hand, if the current charging capacity C10 of the battery 52 in step S213 is greater than or equal to the target charging capacity C11, the process proceeds to step S215, fast charging ends, and the charging control unit 65 stops controlling the charging of the battery 52. ​​Furthermore, Figure 5 At time T22, the current charging capacity C10 becomes greater than or equal to the target charging capacity C11, and the charging of battery 52 ends.

[0064] When in the above Figure 4A In step S211, if the current SOC 70 of battery 52 is determined to be above the upper limit SOC 71, then battery 52 is in an overcharged state. Therefore, the next step is to... Figure 4B Step S217. In step S217, the charging control unit 65 switches from CC charging to CV charging during the fast charging of the battery 52.

[0065] Subsequently, in Figure 4B In step S219, the charging control unit 65 and Figure 4A In step S213, it is similarly determined whether the current charging capacity C10 of battery 52 is less than the target charging capacity C11. If it is determined in step S219 that the current charging capacity C10 of battery 52 is less than the target charging capacity C11, step S219 is executed again to continue CV charging.

[0066] On the other hand, if it is determined in step S219 that the current charging capacity C10 of the battery 52 is greater than or equal to the target charging capacity C11, the process proceeds to step S221, where fast charging (CV charging) ends and the charging control unit 65 ends its control over the charging of the battery 52.

[0067] Next, the inventors prepared mobile phone batteries as shown in Examples 1 to 4 of Table 1 below, and adjusted the charging capacity of the mobile phone batteries to reach the target charging capacity C11 (see reference). Figure 4A The total charging time up to the point of fast charging was measured. Here, total charging time refers to the sum of charging time based on pre-charging and charging time based on fast charging.

[0068] In Examples 1 to 4, the battery pack used as a mobile phone battery uses a so-called NMC ternary lithium-containing transition metal composite oxide containing nickel, manganese, and cobalt as the positive electrode active material, graphite as the negative electrode active material, polyethylene (PE) and polypropylene (PP) as separators, and ethylene carbonate and methyl ethyl carbonate as the electrolyte. In Examples 1 to 4, the first charging rate R1 during fast charging is 11A, and the second charging rate R2 during precharging is 0.2A.

[0069] In the mobile phone battery 50 used in Examples 1 and 2, a battery control device 60 is configured to control charging by the charging control unit 65 performing the charging control of this embodiment, such as... Figure 5 As shown, the precharge SOC 73 is set lower than the lower limit SOC 72. In Examples 1 and 2, the upper limit SOC 71 is 85%, and the corresponding upper limit voltage V71 is 3.9V. The lower limit SOC 72 is 5%, and the corresponding lower limit voltage V72 is 3.3V. The precharge SOC 73 is 0%, and the corresponding precharge voltage V73 is 3.0V.

[0070] On the other hand, the mobile phone batteries used in Examples 3 and 4 differ from those in Examples 1 and 2 in that the pre-charge SOC and lower limit SOC are set to be the same, while the other structures are identical. In Examples 3 and 4, both the lower limit SOC and pre-charge SOC are 5%, corresponding to a voltage of 3.3V. Furthermore, the upper limit SOC in Examples 3 and 4 is the same as the upper limit SOC 71 in Examples 1 and 2, which is 85%, corresponding to an upper limit voltage of 3.9V. In Examples 1 and 3, the charging start voltage is set to 3.0V, while in Examples 2 and 4, the charging start voltage is set to 2.5V.

[0071] The mobile phone batteries of Examples 1 to 4 were charged, and the total charging time was measured. The total charging time for Examples 1 to 4 is shown in Table 1 below.

[0072] Table 1

[0073] Relationship between precharge SOC and lower limit SOC Starting voltage value Total charging time Example 1 Precharge SOC < Lower limit SOC 3.0V 3 minutes and 15 seconds Example 2 Precharge SOC < Lower limit SOC 2.5V 3 minutes and 23 seconds Example 3 Precharge SOC = Lower Limit SOC 3.0V 18 minutes Example 4 Precharge SOC = Lower Limit SOC 2.5V 26 minutes

[0074] As shown in Table 1, it can be seen from Comparative Examples 1 and 3 that the total charging time in Comparative Example 1 is shorter than that in Comparative Example 3. Furthermore, it can be seen from Comparative Examples 2 and 4 that the total charging time in Comparative Example 2 is shorter than that in Comparative Example 4. This can be attributed to the fact that in Examples 1 and 2, the pre-charge SOC 73 is set below the lower limit SOC 72 as in this embodiment, thereby the timing of the transition from pre-charge to fast charging becomes earlier in Comparative Examples 3 and 4. As a result, the charging time during pre-charge is shorter in Examples 1 and 2, thus shortening the total charging time.

[0075] In this embodiment, as described above... Figure 1 As shown, the mobile phone battery 50 includes a housing 51, a battery 52, a power supply unit 56, and a battery control device 60. The battery 52 is disposed within the housing 51 and can be charged at a charging rate of 5C or higher. The power supply unit 56 is disposed within the housing 51. The battery control device 60 is connected to the battery 52 and the power supply unit 56. The battery control device 60 includes a discharge control unit 63 for controlling the discharge from the battery 52 and a charging control unit 65 for controlling the charging of the battery 52. Figure 3As shown, the discharge control unit 63 is configured to discharge the battery 52 until it reaches a predetermined lower limit SOC 72 that is higher than the predetermined pre-charge SOC 73. The charging control unit 65 is configured to: Figure 4A When the SOC of battery 52 (here, the current SOC 70) is lower than the pre-charge SOC 73 as in step S203, it is charged at a second charge rate R2 that is lower than the predetermined first charge rate R1 (see reference). Figure 4A Step S205). The charging control unit 65 is configured such that, as shown in step S205. Figure 4A When the SOC (current SOC 70) of battery 52 is above the pre-charge SOC 73 as in step S207, it is charged at the first charging rate R1 as in step S209.

[0076] In this embodiment, when charging battery 52, if the current SOC 70 is lower than the pre-charge SOC 73, pre-charging is performed at a second charging rate R2; if the current SOC 70 becomes higher than the pre-charge SOC 73, fast charging is performed at a first charging rate R1. Here, conventionally, as shown in Examples 3 and 4 above, the pre-charge SOC 73 and the lower limit SOC 72 are set to the same value. That is, the SOC of battery 52 at the end of CC discharge is the same as the SOC of battery 52 at the start of fast charging. Therefore, the charging time based on pre-charging becomes longer, thereby increasing the total charging time of battery 52.

[0077] However, in this embodiment, such as Figure 5 As shown, the pre-charge SOC 73 is set lower than the lower discharge SOC 72. Therefore, compared to the past, charging of the battery 52 based on pre-charge ends when the current SOC 70 is lower than the lower discharge SOC 72. Therefore, the charging time required for pre-charge can be shortened, and thus the total charging time of the battery 52 can be shortened.

[0078] Furthermore, in this embodiment, in order to reduce the size of the multiple battery packs 53 included in battery 52 (see reference 53), Figure 1 The voltage difference between the batteries in the multiple battery packs 53 is used to equalize the voltage values ​​of the batteries 53 for pre-charging. Therefore, by rapidly charging the batteries 53 after voltage equalization, differences in the charging states of the batteries 53 can be suppressed, and the batteries 52 can be fully charged. In this embodiment, as described above... Figure 5 As shown, by setting the precharge SOC 73 below the lower limit SOC 72, the charging time required for precharging can be shortened. Even with a shortened precharge-based charging time, the voltage values ​​of the multiple battery packs 53 can be equalized through precharging. Therefore, even in this embodiment, the battery 52 can be charged stably.

[0079] In this embodiment, the difference between the pre-charge SOC 73 and the lower limit SOC 72 is 5% to 30% of SOC. For example, if the difference between the pre-charge SOC 73 and the lower limit SOC 72 is less than 5% of SOC, the charging time required for pre-charging becomes relatively longer, and the total charging time of battery 52 becomes a time that many users find lengthy. For example, if the difference between the pre-charge SOC 73 and the lower limit SOC 72 is greater than 30% of SOC, battery 52 becomes unstable due to pre-charging, meaning that the voltage values ​​of the multiple battery packs 53 in battery 52 are difficult to equalize. However, in this embodiment, by making the difference between the pre-charge SOC 73 and the lower limit SOC 72 5% to 30% of SOC, the charging time required for pre-charging can be shortened, and battery 52 can be stabilized, meaning that the voltage values ​​of the multiple battery packs 53 in battery 52 can be easily equalized.

[0080] In this embodiment, Figure 1 The power supply unit 56 includes a wireless power supply device. Therefore, while carrying the mobile phone battery 50, power can be supplied from the power supply unit 56 to, for example, the mobile terminal 80, thereby enabling the mobile terminal 80 (specifically, the built-in battery 82) to be charged. Furthermore, regardless of the connection state of the mobile phone battery 50 to the mobile terminal 80, the mobile terminal 80 can be easily charged by placing the mobile phone battery 50 within a predetermined range of the mobile terminal 80.

[0081] Furthermore, in this embodiment, the battery 52 and the battery control device 60 are included in and implemented by the mobile phone battery 50. However, the battery control device 60 is not limited to an implementation based on the mobile phone battery 50.

[0082] Figure 6 This is a conceptual diagram of a charging system 10A according to another embodiment. (See diagram below.) Figure 6 As shown, the charging system 10A includes a power supply device 20 and a mobile terminal 80A. In the charging system 10A, [the following is omitted] Figure 1 The mobile phone battery 50 shown is as described. The mobile terminal 80A includes a high-output battery 52, a power receiving unit 54, and a battery control device 60. The battery 52, power receiving unit 54, and battery control device 60 of the mobile terminal 80A are respectively connected to… Figure 1 The battery 52, power receiving unit 54, and battery control device 60 of the mobile phone battery 50 are the same. In this way, even if the mobile terminal 80A has a high-output battery 52, power receiving unit 54, and battery control device 60, the same effect as the above embodiment can be obtained.

Claims

1. A battery control device, wherein, The battery control device includes: The discharge control unit controls the discharge from the battery; and The charging control unit controls the charging of the battery. The discharge control unit is configured to at least perform constant current discharge of the battery up to a predetermined lower limit SOC higher than a predetermined pre-charge SOC, wherein the pre-charge SOC is in the range of 0% to 15% of SOC, and the difference between the pre-charge SOC and the lower limit SOC is 5% to 30% of SOC. The charging control unit is configured as follows: When the battery's state of charge (SOC) is lower than the pre-charge SOC, constant current charging is performed at a second charging rate that is lower than the predetermined first charging rate. Furthermore, from the point where the battery's SOC is above the pre-charge SOC and below the lower limit SOC, up to the upper limit SOC, constant current charging is performed at the first charging rate, wherein the upper limit SOC is located in the range of 80% to 95% of SOC. The lower limit SOC is the lower limit value of the current SOC when the battery is discharged with a constant current discharge. The upper limit of SOC is the upper limit of the SOC when the battery is charged with a constant current.

2. The battery control device according to claim 1, wherein, The lower limit of SOC is located in the range of SOC 0% to SOC 15%.

3. A mobile phone battery, wherein, The mobile phone battery has the following features: case; The battery, disposed within the housing, is capable of being charged at a charging rate of 5C or higher. A power supply unit is disposed within the housing; and A battery control device is connected to the battery and the power supply unit. The battery control device includes: A discharge control unit controls the discharge from the battery; and The charging control unit controls the charging of the battery. The discharge control unit is configured to perform discharge from the battery at a constant current until the battery reaches a predetermined lower limit SOC that is higher than a predetermined pre-charge SOC, wherein the pre-charge SOC is in the range of 0% to 15% of SOC, and the difference between the pre-charge SOC and the lower limit SOC is 5% to 30% of SOC. The charging control unit is configured as follows: When the state of charge (SOC) of the battery is lower than the pre-charge SOC, constant current charging is performed at a second charging rate that is lower than the predetermined first charging rate. Furthermore, from the point where the battery's SOC is above the pre-charge SOC and below the lower limit SOC, up to the upper limit SOC, constant current charging is performed at the first charging rate, wherein the upper limit SOC is located in the range of 80% to 95% of SOC. The lower limit SOC is the lower limit value of the current SOC when the battery is discharged with a constant current discharge. The upper limit of SOC is the upper limit of the SOC when the battery is charged with a constant current.

4. The mobile phone battery according to claim 3, wherein, The power transmission unit includes a wireless power transmission device.

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