Patent Description:
When an electronic device is connected to an external power source, a battery may be charged. When the electronic device has a plurality of batteries, the plurality of batteries may be charged at the same time. When charging, each of the plurality of batteries may individually change in battery voltage, and a voltage difference may occur between the plurality of batteries. Battery cell balancing may occur between the plurality of batteries to balance the voltages of the batteries. The battery cell balancing is a phenomenon in which a high voltage battery is discharged and a low voltage battery is charged to reduce a voltage difference between batteries connected in parallel. Due to the battery cell balancing, current may flow from the battery with a higher voltage toward the battery with a lower voltage.

Even if voltage imbalance between a plurality of batteries occurs while charging the plurality of batteries, an electronic device of the related art does not separately manage the voltage imbalance between the plurality of batteries. When there is a difference between voltages between the plurality of batteries, battery cell balancing may cause capacity loss between the plurality of batteries and accelerate battery deterioration. The battery cell balancing phenomenon may continuously cause charge and discharge between the batteries, which may cause a rapid deterioration of the battery life.

The above information is presented as background information only, and to assist with an understanding of the disclosure.

<CIT> discloses an electrical energy storage device includes a plurality of energy cell slots for receiving energy cells; and a controller; wherein the controller is arranged to estimate a characteristic of a cell in each slot; and wherein the controller is arranged to apply charge and discharge currents to each cell slot dependent upon at least one estimated characteristic currently associated with that slot.

<CIT> discloses a method to control storage into and depletion from multiple energy storage devices. The method enables an operative connection between the energy storage devices and respective power converters.

<CIT> discloses a battery charging controlling apparatus for balancing voltages of the charged batteries is provided. The battery charging controlling includes a battery reference voltage generating unit, a voltage balancing unit, and a balance judging unit.

Aspects of the disclosure are to address at least the above-mentioned problems and/or disadvantages, and to provide at least the advantages described below. Accordingly, an aspect of the disclosure is to provide a method of minimizing a voltage difference between a plurality of batteries during charging by distributing a charging current corresponding to a capacity of each of the plurality of batteries when charging a plurality of batteries, and an electronic device to which the method is applied.

In accordance with an aspect of the disclosure, an electronic device is provided, as summarized in independent claim <NUM>.

Accordingly, those of ordinary skill in the art will recognize that various changes and modifications, of the various embodiments described herein can be made without departing from the scope of the disclosure.

The terms and words used in the following description and claims are not limited to the bibliographical meanings, but are merely used to enable a clear and consistent understanding of the disclosure.

Referring to <FIG>, an electronic device <NUM> in a network environment <NUM> may communicate with an electronic device <NUM> via a first network <NUM> (e.g., a short-range wireless communication network), or an electronic device <NUM> or a server <NUM> via a second network <NUM> (e.g., a long-range wireless communication network). According to an embodiment, the electronic device <NUM> may include a processor <NUM>, memory <NUM>, an input device <NUM>, a sound output device <NUM>, a display device <NUM>, an audio module <NUM>, a sensor module <NUM>, an interface <NUM>, a haptic module <NUM>, a camera module <NUM>, a power management module <NUM>, a battery <NUM>, a communication module <NUM>, a subscriber identification module (SIM) <NUM>, and/or an antenna module <NUM>.

The non-volatile memory may include one or more of an internal memory <NUM> and an external memory <NUM>.

The input device <NUM> may receive a command or data to be used by other components (e.g., the processor <NUM>) of the electronic device <NUM>, from the outside (e.g., a user) of the electronic device <NUM>.

According to an embodiment, the antenna module <NUM> may include an antenna including a radiating element composed of a conductive material or a conductive pattern formed in or on a substrate (e.g., printed circuit board (PCB)).

At least some of the above-described components may be coupled mutually and communicate signals (e.g., commands or data) therebetween via an interperipheral communication scheme (e.g., a bus, general purpose input and output (GPIO), serial peripheral interface (SPI), or mobile industry processor interface (MIPI)).

<FIG> is a block diagram illustrating a power management module and battery according to an embodiment of the disclosure.

Referring to <FIG> and <FIG>, block diagram <NUM> illustrates that the power management module <NUM> may include charging circuitry <NUM>, a power adjuster <NUM>, and/or a power gauge <NUM>. The charging circuitry <NUM> may charge the battery <NUM> by using power supplied from an external power source outside the electronic device <NUM>. According to an embodiment, the charging circuitry <NUM> may select a charging scheme (e.g., normal charging or quick charging) based at least in part on a type of the external power source (e.g., a power outlet, a USB, or wireless charging), magnitude of power suppliable from the external power source (e.g., about <NUM> Watt or more), or an attribute of the battery <NUM>, and may charge the battery <NUM> using the selected charging scheme. The external power source may be connected with the electronic device <NUM>, for example, directly via the connecting terminal <NUM> or wirelessly via the antenna module <NUM>.

The power adjuster <NUM> may generate a plurality of powers having different voltage levels or different current levels by adjusting a voltage level or a current level of the power supplied from the external power source or the battery <NUM>. The power adjuster <NUM> may adjust the voltage level or the current level of the power supplied from the external power source or the battery <NUM> into a different voltage level or current level appropriate for each of some of the components included in the electronic device <NUM>. According to an embodiment, the power adjuster <NUM> may be implemented in the form of a low drop out (LDO) regulator or a switching regulator. The power gauge <NUM> may measure use state information about the battery <NUM> (e.g., a capacity, a number of times of charging or discharging, a voltage, or a temperature of the battery <NUM>).

The power management module <NUM> may determine, using, for example, the charging circuitry <NUM>, the power adjuster <NUM>, or the power gauge <NUM>, charging state information (e.g., lifetime, over voltage, low voltage, over current, over charge, over discharge, overheat, short, or swelling) related to the charging of the battery <NUM> based at least in part on the measured use state information about the battery <NUM>. The power management module <NUM> may determine whether the state of the battery <NUM> is normal or abnormal based at least in part on the determined charging state information. If the state of the battery <NUM> is determined to abnormal, the power management module <NUM> may adjust the charging of the battery <NUM> (e.g., reduce the charging current or voltage, or stop the charging). According to an embodiment, at least some of the functions of the power management module <NUM> may be performed by an external control device (e.g., the processor <NUM>).

The battery <NUM>, according to an embodiment, may include a protection circuit module (PCM) <NUM>. The PCM <NUM> may perform one or more of various functions (e.g., a pre-cutoff function) to prevent a performance deterioration of, or a damage to, the battery <NUM>. The PCM <NUM>, additionally or alternatively, may be configured as at least part of a battery management system (BMS) capable of performing various functions including cell balancing, measurement of battery capacity, count of a number of charging or discharging, measurement of temperature, or measurement of voltage.

According to an embodiment, at least part of the charging state information or use state information regarding the battery <NUM> may be measured using a corresponding sensor (e.g., a temperature sensor) of the sensor module <NUM>, the power gauge <NUM>, or the power management module <NUM>. According to an embodiment, the corresponding sensor (e.g., a temperature sensor) of the sensor module <NUM> may be included as part of the PCM <NUM>, or may be disposed near the battery <NUM> as a separate device.

<FIG> is another block diagram illustrating an electronic device according to an embodiment of the disclosure.

Referring to <FIG>, <FIG> and <FIG>, the electronic device <NUM> (e.g., the electronic device <NUM> of <FIG>) includes a plurality of batteries <NUM> and the power management module <NUM>, a plurality of sensors <NUM>, a plurality of current limiting ICs <NUM>, and the processor <NUM>, which are arranged in a housing <NUM>.

In an embodiment, the housing <NUM> may define the appearance of the electronic device <NUM>. The housing <NUM> may include a front plate that forms a front or first surface of the electronic device <NUM>, a back plate that forms a back or second surface of the electronic device <NUM>, and a side member that surrounds a space between the front plate and the back plate. The housing <NUM> may protect the plurality of batteries <NUM>, the power management module <NUM>, the plurality of sensors <NUM>, the plurality of current limiting ICs <NUM>, and the processor <NUM> from an external shock.

In an embodiment, the plurality of batteries <NUM> are arranged in the housing <NUM>. The plurality of batteries <NUM> may include a first battery <NUM> and a second battery <NUM>. However, the embodiment is not limited thereto, and the plurality of batteries <NUM> may include three or more batteries. In this case, the electronic device <NUM> may operate as a multi-battery.

In an embodiment, each of the first and second batteries <NUM> and <NUM> may independently supply power required to operate the electronic device <NUM>. Each of the first and second batteries <NUM> and <NUM> may be independently charged. Each of the first and second batteries <NUM> and <NUM> may have a different capacity. For example, the first battery <NUM> may be a main battery, and the second battery <NUM> may be a sub battery. Each of the first and second batteries <NUM> and <NUM> may be discharged at different rates.

In an embodiment, the first and second batteries <NUM> and <NUM> may perform a balancing operation to match the battery levels of each other. When the first and second batteries <NUM> and <NUM> perform the balancing operation, a difference in battery level between the first and second batteries <NUM> and <NUM> may be reduced.

In an embodiment, the power management module <NUM> may include the charging circuitry <NUM>, the power adjuster <NUM>, and the power gauge <NUM>. The power management module <NUM> may be implemented as a power management integrated circuit (PMIC). The power management module <NUM> controls the plurality of batteries <NUM>. For example, the power management module <NUM> may control the battery level of each of the first and second batteries <NUM> and <NUM>. The power management module <NUM> may control the charging and/or discharging of each of the first and second batteries <NUM> and <NUM> to control the battery level of each of the first and second batteries <NUM> and <NUM>. The power management module <NUM> may control the charging and/or discharging of each of the first and second batteries <NUM> and <NUM> by using the plurality of current limiting ICs <NUM>.

In an embodiment, the plurality of sensors <NUM> may measure the current flowing through a specified portion and/or the voltage of a specified portion. The plurality of sensors <NUM> may include first to third sensors <NUM>, <NUM> and <NUM>.

In an embodiment, the plurality of current limiting ICs <NUM> control the currents flowing into the plurality of batteries <NUM>. The plurality of current limiting ICs <NUM> limit the maximum intensity of the current flowing into each of the plurality of batteries <NUM>. The plurality of current limiting ICs <NUM> may include a first current limiting IC <NUM> and a second current limiting IC <NUM>. However, the disclosure is not limited thereto, and when the electronic device <NUM> operates with a multi-battery, the plurality of current limiting ICs <NUM> may include three or more current limiting ICs.

In an embodiment, the first sensor <NUM> may measure the total sum of the currents flowing from the power management module <NUM> to the plurality of batteries <NUM> and the total voltage of the plurality of batteries <NUM>. <FIG> illustrates a case where the first sensor <NUM> is separately arranged. However, the disclosure is not limited thereto, and the first sensor <NUM> may be included in the power gauge <NUM>. In this case, the power gauge <NUM> may measure the total sum of currents flowing into the plurality of batteries <NUM> and the total voltage of the plurality of batteries <NUM>.

In an embodiment, the second sensor <NUM> may measure the current flowing into the first battery <NUM> and the voltage of the first battery <NUM>. <FIG> illustrates a case where the second sensor <NUM> is separately arranged. However, the disclosure is not limited thereto, and the second sensor <NUM> may be included in the first current limiting IC <NUM>. In this case, the first current limiting IC <NUM> may measure the current flowing into the first battery <NUM> and the voltage of the first battery <NUM>.

In an embodiment, the third sensor <NUM> may measure the current flowing into the second battery <NUM> and the voltage of the second battery <NUM>. <FIG> illustrates a case where the third sensor <NUM> is separately arranged. However, the disclosure is not limited thereto, and the third sensor <NUM> may be included in the second current limiting IC <NUM>. In this case, the second current limiting IC <NUM> may measure the current flowing into the second battery <NUM> and the voltage of the second battery <NUM>.

In an embodiment, the first current limiting IC <NUM> may limit the current flowing into the first battery <NUM>. The first current limiting IC <NUM> may set the first battery <NUM> to a charging state or a discharging state. The first current limiting IC <NUM> may limit the maximum intensity of the current flowing from the power management module <NUM> into the first battery <NUM> in the charging state. The first current limiting IC <NUM> may limit the balancing operation between the first and second batteries <NUM> and <NUM> in the charging state. The first current limiting IC <NUM> may transmit, to the processor <NUM>, information about the voltage of the first battery <NUM>, the charging current flowing into the first battery <NUM>, and/or the discharging current output from the first battery <NUM>.

In an embodiment, the second current limiting IC <NUM> may limit the current flowing into the second battery <NUM>. The second current limiting IC <NUM> may set the second battery <NUM> to a charging state or a discharging state. The second current limiting IC <NUM> may limit the maximum intensity of the current flowing from the power management module <NUM> into the second battery <NUM> in the charging state. The second current limiting IC <NUM> may limit the balancing operation between the first and second batteries <NUM> and <NUM> in the charging state. The second current limiting IC <NUM> may transmit, to the processor <NUM>, information about the voltage of the second battery <NUM>, the charging current flowing into the second battery <NUM>, and/or the discharging current output from the second battery <NUM>.

In an embodiment, the processor <NUM> is operationally connected to the plurality of batteries <NUM>, the power management module <NUM>, the plurality of temperature sensors <NUM>, and the plurality of current limiting ICs <NUM>. The processor <NUM> may obtain information about the plurality of batteries <NUM> through the charging circuitry <NUM> and the power gauge <NUM> of the power management module <NUM>. For example, the processor <NUM> may know information about the sum of battery voltages, charging currents, discharging currents, and/or battery levels of the first and second batteries <NUM> and <NUM>. The processor <NUM> may set the maximum intensities of the charging currents flowing into the first and second batteries <NUM> and <NUM> and/or whether to block the charging current.

In an embodiment, in the electronic device <NUM> to which a multi-battery structure is applied, each battery may be independently charged in a parallel structure, thereby causing a difference in charging time between batteries.

<FIG> is a view illustrating charging of first and second batteries according to an embodiment of the disclosure.

Referring to <FIG>, block diagram <NUM> illustrates that the first and second batteries <NUM> and <NUM> may have a voltage lower than a first voltage V1, which is a fully charged voltage. The power management module <NUM> may set both the first and second batteries <NUM> and <NUM> to the charging state. The power management module <NUM> may allow charging currents to flow into the first and second batteries <NUM> and <NUM>.

In an embodiment, the power management module <NUM> may set the sum of the first charging current I1 flowing from the charging circuitry <NUM> to the first battery <NUM> and the second charging current I2 flowing from the charging circuitry <NUM> into the second battery <NUM> to charge the first and second batteries <NUM> and <NUM>. The first and second charging currents I1 and I2 flowing into the first and second batteries <NUM> and <NUM> may vary depending on the battery capacities of the first and second batteries <NUM> and <NUM>.

In an embodiment, the power management module <NUM> may set the charging currents based on the capacities of the first and second batteries <NUM> and <NUM>. The power management module <NUM> may set the charging currents to be less than or equal to the maximum currents allowed by the first and second batteries <NUM> and <NUM>. The power management module <NUM> may set the charging currents such that the first and second batteries <NUM> and <NUM> are fully charged substantially at the same time. For example, when the capacity remaining until the first battery <NUM> is fully charged is a first capacity and the capacity remaining until the second battery <NUM> is fully charged is a second capacity, the power management module <NUM> may set the charging currents flowing into the first and second batteries <NUM> and <NUM> in proportion to the first capacity and the second capacity. The sum of the charging currents flowing into the first and second batteries <NUM> and <NUM> may be the sum of a first charging maximum set current that may flow into the first battery <NUM> and a second charging maximum set current that may flow into the second battery <NUM>.

In an embodiment, a voltage difference may occur between the first and second batteries <NUM> and <NUM>. According to an impedance state of each of the first and second batteries <NUM> and <NUM>, the charging currents and the discharging currents of the first and second batteries <NUM> and <NUM> may be different from each other. For example, the first battery <NUM> may have a second voltage V2 lower than the first voltage V1, and the second battery <NUM> may have a third voltage V3 lower than the second voltage V2.

In an embodiment, current may flow from the first battery <NUM> having the second voltage V2 to the second battery <NUM> having the third voltage V3. Because the current flows from the first battery <NUM> having a high voltage to the second battery <NUM> having a low voltage, the battery cell balancing may occur in which the second battery <NUM> is charged and the first battery <NUM> is discharged. As the voltage difference between the first and second batteries <NUM> and <NUM> increases, the battery cell balancing may increase. When the battery cell balancing occurs between the first and second batteries <NUM> and <NUM>, the lifespans of the first and second batteries <NUM> and <NUM> may be reduced, or the first battery <NUM> and the second battery <NUM> may deteriorate.

<FIG> is a view illustrating blocking of charging of a first battery, and charging of a second battery, according to an embodiment of the disclosure.

Referring to <FIG>, block diagram <NUM> illustrates that the first battery <NUM> may have a first voltage V1 that is a fully charged voltage. The second battery <NUM> may have a third voltage V3 lower than the first voltage V1. A second voltage V2 is lower than the first voltage V1 in each. The first battery <NUM> may be in the fully charged state in which the voltage of the first battery <NUM> reaches the first voltage V1, which is the fully charged voltage, and the inflow of the charging current is blocked so that the first battery <NUM> is not charged. The second battery <NUM> may be in a charging state in which the second battery <NUM> has the third voltage V3 lower than the first voltage V1 which is the fully charged voltage, so that a charging current is introduced. The power management module <NUM> may measure the voltages of the first and second batteries <NUM> and <NUM>. The power management module <NUM> may set each of the first and second batteries <NUM> and <NUM> to a fully charged state or a charging state based on the voltages of the first and second batteries <NUM> and <NUM>. For example, the power management module <NUM> may set the first battery <NUM> to the fully charged state and set the second battery <NUM> to a charging state. The power management module <NUM> may block the charging current flowing into the first battery <NUM> by using the first current limiting IC <NUM> and introduce the charging current into the second battery <NUM>.

In an embodiment, when minimizing battery cell balancing occurring between the first and second batteries <NUM> and <NUM> during charging of the first and second batteries <NUM> and <NUM>, the lifespans of the first and second batteries <NUM> and <NUM> may be increased, and the first and second batteries <NUM> and <NUM> may be prevented from being deteriorated. The processor (e.g., the processor <NUM> of <FIG>) may be configured to allow the first and second batteries <NUM> and <NUM> to be charged while minimizing the voltage difference between the first and second batteries <NUM> and <NUM> in order to minimize the battery cell balancing between the first and second batteries <NUM> and <NUM> during charging.

<FIG> is a flowchart illustrating a method of setting a charging current of each of a plurality of batteries (e.g., the first and second batteries <NUM> and <NUM> of <FIG>) according to an embodiment of the disclosure.

Referring to <FIG>, in operation <NUM> of flowchart <NUM>, an electronic device (e.g., the electronic device <NUM> of <FIG>) according to an embodiment sets a total charging current 'I' output from a charging circuitry (e.g., the charging circuitry <NUM> of <FIG>) of a power management module (e.g., the power management module <NUM> of <FIG>). It is possible to set, as the total charging current `I', the sum of the first charging current I1 flowing from the charging circuitry <NUM> to the first battery <NUM> and the second charging current I2 flowing into the second battery <NUM> in order to charging the electronic device <NUM> including the first and second batteries (e.g., the first and second batteries <NUM> and <NUM> of <FIG>).

In an embodiment, the processor <NUM> may minimize the voltage difference between the first and second batteries <NUM> and <NUM> by setting the total charging current `I' such that the initial current setting at the start of charging is optimized for the capacity.

In operation <NUM>, the electronic device <NUM> according to an embodiment sets an individual charging current flowing into each of the plurality of batteries <NUM> and <NUM> in proportion to the total capacity of each of the batteries <NUM> and <NUM>. For example, when the first battery <NUM> has the first capacity C1, the second battery <NUM> has the second capacity C2, and the total charging current `I' is set, the first and second charging currents I1 and I2 are set to be proportional to the first and second capacities C1 and C2.

In an embodiment, the first charging current I1 is a value obtained by multiplying a value obtained by dividing the first capacity C1 by the sum of the first and second capacities C1 and C2 by the total charging current `I'. The second charging current I2 is a value obtained by multiplying a value obtained by dividing the second capacity C2 by the sum of the first and second capacities C1 and C2 by the total charging current `I'. For example, when the first battery <NUM> having the total capacity of <NUM>,<NUM> mAh and the second battery <NUM> having the total capacity of <NUM>,<NUM> mAh are charged with <NUM>,500mAh, the first charging current I1 and the second charging current I2 are calculated as follows.

Total charging current 'I' = <NUM>, <NUM> mA set in the charging circuitry <NUM> <MAT> <MAT>.

In an embodiment, the processor <NUM> distributes the total charging current 'I' to be proportional to the total capacity of each of the first and second batteries <NUM> and <NUM>, such that the first and second charging currents I1 and I2 flowing into the first and second batteries <NUM> and <NUM>, respectively are set. The processor <NUM> may set the maximum current flowing into the first and second batteries <NUM> and <NUM> by using a distribution algorithm. The processor <NUM> sets the first and second charging currents I1 and I2 regardless of the current remaining capacities of the first and second batteries <NUM> and <NUM>.

In operation <NUM>, the electronic device <NUM> according to an embodiment may determine whether the total charging current `I' has changed. The total charging current `I' set at the charging circuitry <NUM> may vary in real time with various events such as a type of a connected charging cable, a heating control algorithm of the processor <NUM>, a communication failure of a communication module (e.g., the communication module <NUM> of <FIG>), a defect of the connected charging cable, defects of the first battery <NUM> and/or the second battery <NUM>, or a poor charging state, or control of a user. The processor <NUM> may repeat operation <NUM> when the total charging current `I' is changed (operation <NUM>-Yes). When the total charging current `I' is kept constant (operation <NUM>-No), the processor <NUM> may proceed to operation <NUM>.

In an embodiment, the processor <NUM> recalculates the first and second charging currents I1 and I2 flowing into the first and second batteries <NUM> and <NUM> in real time whenever the total charging current `I' set at the charging circuitry <NUM> is changed. The maximum charging current distribution algorithm of the processor <NUM> may be performed again whenever the total charging current `I' set at the charging circuitry <NUM> is changed. The processor <NUM> may set the current flowing currently and actually in each of the first and second batteries <NUM> and <NUM> to be proportional to the total capacity of each of the first and second batteries <NUM> and <NUM> to control the voltages of the first and second batteries <NUM> and <NUM> to be substantially the same in the charging operation.

In operation <NUM>, the electronic device <NUM> according to an embodiment may maintain an individual charging current. The processor <NUM> may maintain the first and second charging currents I1 and I2. The processor <NUM> may be configured to allow the first and second batteries <NUM> and <NUM> to receive the total charging current `I' divided by capacity. The processor <NUM> may maintain the intensities of the first and second charging currents I1 and I2 flowing into the first and second batteries <NUM> and <NUM>, respectively while the total charging current' I' is kept constant. In the processor <NUM>, the processor <NUM> may minimize the charging imbalance between the first and second batteries <NUM> and <NUM> by allowing the total charging current `I' set at the charging circuitry <NUM> to flow a little more into one of the first or second battery <NUM> or <NUM>.

<FIG> is a flowchart illustrating a method of charging a plurality of batteries (e.g., the first and second batteries <NUM> and <NUM> of <FIG>) providing examples for better understanding of the present invention, which is not covered by the claims.

Referring to <FIG>, a method of minimizing battery cell balancing may be applied on the assumption that the first and second batteries <NUM> and <NUM> are in a charging state. When the discharging current is blocked due to the battery cell balancing by using a plurality of current limiting ICs (e.g., the first and second current limiting ICs <NUM> and <NUM> of <FIG>) in a discharging state, the current output itself from the first and second batteries <NUM> and <NUM> may be blocked. In this case, the system current required for the operation of the electronic device <NUM> may be insufficient, so that the operation of the electronic device <NUM> may stop. The processor <NUM> may be set to allow a method of minimizing a voltage difference between the first and second batteries <NUM> and <NUM> to be applied only in the charging operation.

In operation <NUM> of flowchart <NUM>, the electronic device <NUM> may sense a voltage of each of the power management module (e.g., the power management module <NUM> of <FIG>) and the batteries <NUM> and <NUM>, and may determine whether the mode is the first mode or the second mode based on the voltage of the power management module <NUM>.

The charging of the first and second batteries <NUM> and <NUM> may begin when there is imbalance between the voltages of the first and second batteries <NUM> and <NUM>. The processor <NUM> may sense the voltage of the charging circuitry <NUM> of the power management module <NUM>, the voltage of the first battery <NUM>, and the voltage of the second battery <NUM>.

The processor <NUM> may determine whether the mode is the first mode that is a constant voltage (CV) mode or the second mode that is a constant current (CC) mode based on the voltage of the charging circuitry <NUM> of the power management module <NUM>. The processor <NUM> may control the charging speed of the first or second battery <NUM> or <NUM> to perform balanced charging between the first and second batteries <NUM> and <NUM> depending on which of the first and second modes. The processor <NUM> may attempt to reduce the voltage difference between the first and second batteries <NUM> and <NUM> in the first mode and to increase the charging speed of the first and second batteries <NUM> and <NUM> in the second mode. The processor <NUM> may determine whether to reduce the voltage difference or increase the charging speed in terms of the current total charging capacities of the first and second batteries <NUM> and <NUM>.

In operation <NUM>, the electronic device <NUM> may determine whether each voltage difference between the plurality of batteries <NUM> and <NUM> is greater than a first threshold voltage. The processor <NUM> may check whether the voltage difference between the first and second batteries <NUM> and <NUM> is large. When the voltage difference between the first and second batteries <NUM> and <NUM> is greater than the first threshold voltage (operation <NUM>-Yes), the processor <NUM> may define the current state as a battery imbalance state in which the voltage difference between the first and second batteries <NUM> and <NUM> is large. The processor <NUM> may proceed to operation <NUM> when the voltage difference between the first and second batteries <NUM> and <NUM> is greater than the first threshold voltage (operation <NUM>-Yes). When the voltage difference between the first battery <NUM> and the second battery <NUM> is smaller than the first threshold voltage (operation <NUM>-No), the processor <NUM> may define the current state as the battery balance state in which the voltage difference between the first and second batteries <NUM> and <NUM> is small. When the voltage difference between the first and second batteries <NUM> and <NUM> is smaller than the first threshold voltage (operation <NUM>-No), the processor <NUM> may proceed to operation <NUM>.

The electronic device <NUM> may perform charging in operation <NUM>. When the batteries are in a balanced state, it is not necessary to perform an operation of reducing the voltage difference between the first and second batteries <NUM> and <NUM> during charging. The processor <NUM> may determine that the voltage difference between the first and second batteries <NUM> and <NUM> is within a normal range and perform normal charging.

The electronic device <NUM> may determine whether the electronic device is in the first mode in operation <NUM>. The first mode may be a mode in which the charging voltage is kept constant because the voltage of the power management module <NUM> is equal to or greater than a specified ratio compared to the fully charged voltage. The second mode may be a mode in which the charging current is kept constant because the voltage of the power management module <NUM> is equal to or less than a specified ratio compared to the fully charged voltage. The processor <NUM> may prioritize minimizing battery cell balancing in the first mode. The processor <NUM> may prioritize a fast charging time of all the first and second batteries <NUM> and <NUM> in the second mode. The processor <NUM> may perform operation <NUM> when the processor <NUM> is in the first mode (operation <NUM>-Yes). The processor <NUM> may perform operation <NUM> when the processor <NUM> is in the second mode (operation <NUM>-No).

In operation <NUM>, the electronic device <NUM> may block a charging current and a discharging current of a battery having a high voltage (for example, the first battery <NUM>). When the voltage of the first battery <NUM> among the first and second batteries <NUM> and <NUM> is large, the processor <NUM> may block the charging current to prevent the charging current from flowing into the first battery <NUM>. When the processor <NUM> is in the first mode, the processor <NUM> may stop charging the first battery <NUM> and charge only the second battery <NUM> to quickly reduce the voltage difference between the first and second batteries <NUM> and <NUM>. For example, the processor <NUM> may set the first current limiting IC (e.g., the first current limiting IC <NUM> of <FIG>) to a supplement mode which is a mode of blocking current, thereby blocking the current flowing into the first battery <NUM>. The processor <NUM> may be set to block the charging current and the discharging current of the first battery <NUM> for a specified time.

The processor <NUM> may block the discharging current output from the first battery <NUM> by using the first current limiting IC <NUM>. The processor <NUM> may block the discharging current of the first battery <NUM> to prevent the first battery <NUM> from being discharged due to the occurrence of the battery cell balancing by which a current flows toward the second battery <NUM> having a lower voltage than the first battery <NUM>.

The system current required by the electronic device <NUM> may be supplied from the second battery <NUM>. The processor <NUM> may control the power management module <NUM> to supply the system current from an external charging device such that the system current is not short.

In operation <NUM>, the electronic device <NUM> may limit the intensity of a charging current of a battery having a high voltage. When the voltage of the first battery <NUM> among the first and second batteries <NUM> and <NUM> is high, the processor <NUM> may limit the charging current flowing into the first battery <NUM> to a predetermined size or less. In the second mode, the processor <NUM> may allow the second battery <NUM> to be charged while limiting the charging of the first battery <NUM> such that the voltage difference may be gradually reduced while the first and second batteries <NUM> and <NUM> are rapidly charged as a whole. When the voltage of the charging circuitry <NUM> of the power management module <NUM> is in the second mode, the processor <NUM> may constantly limit the current flowing into the first battery <NUM> because the overall charging of the first and second batteries <NUM> and <NUM> may be slow when the charging of the first battery <NUM> having a high voltage is blocked. The processor <NUM> may be set to limit the intensity of the charging current of the first battery <NUM> for a specified time.

The processor <NUM> may set the maximum charging current which is the maximum current with that the first and second batteries <NUM> and <NUM> can be charged without being damaged. The processor <NUM> may block the charging current to the first battery <NUM> having a high voltage in the first mode or limit the intensity of the charging current to the first battery <NUM> having a high voltage in the second mode, such that the charging current of the second battery <NUM> may be prevented from exceeding the maximum charging current to prevent the second battery <NUM> from being damaged. The second battery <NUM> may maintain the maximum charging current to catch up with the voltage of the first battery <NUM>.

In operation <NUM>, the electronic device <NUM> may determine whether the difference between the voltages of the first battery <NUM> and the second battery <NUM> is smaller than the second threshold voltage. The processor <NUM> may determine whether the voltage difference between the first and second batteries <NUM> and <NUM> has decreased after a specified time has elapsed since the charging current of the first battery <NUM> having the high voltage is limited. When the voltage difference between the first and second batteries <NUM> and <NUM> is smaller than the second threshold voltage (operation <NUM>-Yes), the processor <NUM> may define it as a battery balance state. When the voltage difference between the first and second batteries <NUM> and <NUM> is less than the second threshold voltage (operation <NUM>-Yes), the processor <NUM> may proceed to operation <NUM>. When the voltage difference between the first and second batteries <NUM> and <NUM> is greater than the second threshold voltage in operation <NUM> (No), the processor <NUM> may define it as a battery imbalance state. When the voltage difference between the first and second batteries <NUM> and <NUM> is greater than the second threshold voltage (operation <NUM>-No), the processor <NUM> may proceed to operation <NUM>.

In operation <NUM>, the electronic device <NUM> may cancel blocking of the charging and discharging currents of the first battery <NUM> having the high voltage. Because of the return to the battery balance state, the processor <NUM> may perform charging in a general manner. After performing operation <NUM>, the processor <NUM> may be configured to perform operation <NUM> every specified time period.

In operation <NUM>, the electronic device <NUM> may maintain blocking of charging and discharging currents of the first battery <NUM> having the high voltage. The processor <NUM> may determine that the first and second batteries <NUM> and <NUM> are in an imbalanced state, and perform charging while the voltages of the first and second batteries <NUM> and <NUM> similarly match each other. After performing operation <NUM>, the processor <NUM> may be configured to perform operation <NUM> every specified time period.

The processor <NUM> may select one charging control method depending on whether the balance charging in the first mode and the second mode prioritizes minimizing battery cell balancing or charging time. Both charging control methods may proceed until the voltage levels of the first and second batteries <NUM> and <NUM> are similar to each other. The processor <NUM> may adjust the voltages of the first and second batteries <NUM> and <NUM> to be similar to each other by allowing the first and second batteries <NUM> and <NUM> to perform balanced charging.

<FIG> is a view illustrating a method of charging a plurality of batteries in a first mode for better understanding of the present invention, which is not covered by the claims.

Referring to <FIG>, block diagrams <NUM> illustrate that the first battery <NUM> may have a higher voltage than the second battery <NUM>. The initial voltage of the first battery <NUM> may be a first voltage V1 that is a fully charged voltage or a target voltage. The initial voltage of the second battery <NUM> may be a fourth voltage V4. For example, the first voltage V1 may be about <NUM>%, and the fourth voltage V4 may be about <NUM>%. In this case, the voltage of the charging circuit (e.g., the charging circuitry <NUM> of <FIG>) of the power management module (e.g., the power management module <NUM> of <FIG>) may be in the range of about <NUM>% to about <NUM>%. The processor <NUM> may perform the charging in the first mode based on the fact that the voltage of the power management module <NUM> is close to the fully charged voltage or the target voltage.

The processor <NUM> may block both the charging current flowing into the first battery <NUM> and the discharging current flowing from the first battery <NUM> to the second battery <NUM>. The processor <NUM> may control the power management module <NUM> such that the power management module <NUM> charges only the second battery <NUM>. The power management module <NUM> may charge the second battery <NUM> to raise the voltage of the second battery <NUM> to the first voltage V1 through second and third voltages V2 and V3. Accordingly, the voltage difference between the first and second batteries <NUM> and <NUM> may be reduced or eliminated.

<FIG> is a view illustrating a method of charging a plurality of batteries in a second mode for better understanding of the present invention, which is not covered by the claims.

Referring to <FIG>, block diagrams <NUM> illustrate that the first battery <NUM> may have a higher voltage than the second battery <NUM>. The initial voltage of the first battery <NUM> may be a third voltage V3 which is a voltage lower than the fully charged voltage or the target voltage. The initial voltage of the second battery <NUM> may be a fourth voltage V4. For example, the third voltage V3 may be about <NUM>%, and the fourth voltage V4 may be about <NUM>%. In this case, the voltage of the charging circuit (e.g., the charging circuitry <NUM> of <FIG>) of the power management module (e.g., the power management module <NUM> of <FIG>) may be in the range of about <NUM>% to about <NUM>%. The processor <NUM> may perform charging in the second mode based on the fact that the voltage of the power management module <NUM> is lower than the fully charged voltage or the target voltage.

The processor <NUM> may limit the intensity of the charging current flowing into the first battery <NUM>. For example, the processor <NUM> may limit the first charging current flowing into the first battery <NUM> to be smaller than the second charging current flowing into the second battery <NUM>. In this case, when charging is performed in the power management module <NUM>, while the voltage of the second battery <NUM> rises from the fourth voltage V4 to the third voltage V3, the voltage of the first battery <NUM> may not rise from the third voltage V3 to the second voltage V2, but may rise to a first intermediate voltage A1 between the second and third voltages V2 and V3. Thereafter, the power management module <NUM> may charge the first and second batteries <NUM> and <NUM> such that the voltage of the first battery <NUM> also rises to the second voltage V2 at the time point when the voltage of the second battery <NUM> rises to the second voltage V2. Accordingly, the voltage difference between the first and second batteries <NUM> and <NUM> may be reduced or eliminated.

According to the embodiments of the disclosure, each of the plurality of batteries may receive a charging current distributed corresponding to its capacity to minimize the voltage difference between the plurality of batteries.

In addition, according to the embodiments of the disclosure, charging may be performed while the voltage difference generated between the plurality of batteries is reduced, thereby minimizing a decrease in battery lifespan caused by battery cell balancing during charging.

In addition, various effects that are directly or indirectly understood through the disclosure may be provided.

Claim 1:
An electronic device (<NUM>) comprising:
a housing (<NUM>);
a plurality of batteries (<NUM>) arranged in the housing (<NUM>);
a power management module (<NUM>) configured to control the plurality of batteries (<NUM>);
a plurality of current limiting integrated circuits (ICs) configured to limit a maximum intensity of a current flowing into each of the plurality of batteries (<NUM>); and
at least one processor (<NUM>) operationally connected to the plurality of batteries (<NUM>), the power management module (<NUM>) and the plurality of current limiting ICs (<NUM>),
wherein the at least one processor (<NUM>) is configured to:
set a total charging current output from the power management module (<NUM>),
set an individual charging current flowing into each of the plurality of batteries (<NUM>) in proportion to a total capacity of each of the plurality of batteries (<NUM>) regardless of current remaining capacities of the plurality of batteries (<NUM>), and
recalculate the individual charging currents for each of the plurality of batteries (<NUM>) in real-time whenever the total charging current changes with an event during charging the plurality of batteries (<NUM>).