KR20170017600A - Portable electronic device for aging mitigating of power supply-connected batteries - Google Patents

Abstract

The present invention provides a portable electronic device, comprising: a battery for supplying power to the portable electronic device; a battery control logic for controlling charging and discharging of the battery; a charge buffer for buffering charge; a charge buffer control logic for controlling charging and discharging of the charge buffer; and a power control module for controlling the battery control logic to block the power from being discharged from the battery and for controlling the charge buffer control logic to discharge charge stored in the charge buffer when the supply power is insufficient to the power requirement of the portable electronic device while the portable electronic device is operated by the supply power supply of an external power supply device.

Description

≪ Desc / Clms Page number 1 > PORTABLE ELECTRONIC DEVICE FOR AGING MITIGATING OF POWER SUPPLY-CONNECTED BATTERIES < RTI ID = 0.0 >

The following embodiments are directed to portable electronic devices for aging relief of batteries connected to a power supply.

Battery powered portable electronic devices range from small smart phones to high-performance notebook computers.

Many users expect that these portable electronic devices will not be degraded in service life because they are not used because the power is supplied from the charger, while the portable electronic devices are usually charged with a dedicated charger sold in sets in the office or at home. However, manufacturers are developing products with the least amount of power supply size and capacity to reduce their portability and cost, and therefore, unlike the user's expectation, a smaller capacity power supply would require a maximum power usage It causes charging and discharging of the built-in battery. Therefore, even if the battery is always supplied with power from the dedicated charger, the battery built in the device is aged.

According to one embodiment, aging of the battery can be alleviated when the battery is connected to the power supply.

According to one aspect, a portable electronic device includes a battery that supplies power to the portable electronic device; Battery control logic for controlling charging and discharging of the battery; A charge buffer for buffering charges; A charge buffer control logic for controlling charge and discharge of the charge buffer; And to prevent the power from the battery from being drawn out when the power supply is insufficient for the peak power requirement of the portable electronic device while the portable electronic device is operating by the power supply of an external power supply And a power control module for controlling the battery control logic and for controlling the charge buffer control logic to discharge the charge stored in the charge buffer.

The power capacity of the power supply is designed based on the average power consumption of the portable electronic device, and the average power consumption may be less than the peak power requirement of the portable electronic device.

The power control module may control the charge buffer control logic and the battery control logic such that the charge buffer is preferentially charged more than the battery when the supply power is greater than the peak power requirement.

The power control module may measure at least one of a voltage and a current supplied to the load and determine whether the power supply is insufficient for the power demand based on at least one of the measured voltage and the current.

The charge buffer may comprise electric double layer capacitors.

The capacity of the charge buffer may be determined based on at least one of an average power capacity of the power supply unit, an instantaneous power capacity of the battery, and the peak power requirement.

Wherein the capacity of the charge buffer is at least one of an average remaining capacity (SOC) of a battery, a remaining capacity swing (SOC swing), a health state of a battery (SOH) deterioration with respect to the remaining capacity swing, a discharge depth (DOD) Based on the simulation results.

The charge buffer may have a capacitance of 5 mF to 10 mF.

The charge buffer control logic may include a power converter.

The portable electronic device comprising: a processor for driving the portable electronic device; And a DC-DC converter that converts a DC voltage of an external power supply that supplies power to the portable electronic device to a DC voltage for the processor.

The power control module may determine whether the power supply is insufficient for the power demand based on at least one of a voltage and a current output by the DC-DC converter.

The processor may predict the power demand based on a program being actuated and provide information to the power control module in relation to the predicted power demand.

According to one aspect, a portable electronic device includes a battery that supplies power to the portable electronic device; Battery control logic for controlling charging and discharging of the battery; A charge buffer for buffering charge; A charge buffer control logic for controlling charge and discharge of the charge buffer; A processor for driving the portable electronic device; And a DC-DC converter for converting a DC voltage of an external power supply for supplying power to the portable electronic device to a DC voltage for the processor, Controls the battery control logic and the charge buffer control logic such that the insufficient power is not drawn out of the battery when the program executed in the portable electronic device is less than the required power requirement.

Wherein the processor controls the charge buffer control logic to discharge the charge stored in the charge buffer when the power output by the DC-DC converter is less than a power requirement required by a program running on the portable electronic device, The battery control logic may be controlled to block power from being drawn from the battery.

The processor may control the charge buffer control logic and the battery control logic such that the charge buffer is preferentially charged more than the battery when the power output by the DC-DC converter is greater than the power demand.

The power capacity of the power supply is designed based on the average power consumption of the portable electronic device, and the average power consumption may be less than the peak power requirement of the portable electronic device.

The charge buffer may comprise an electric double layer capacitor.

The capacity of the charge buffer may be determined based on at least one of an average power capacity of the power supply and an instantaneous power capacity of the battery.

The capacity of the charge buffer may be determined according to a simulation result based on at least one of an average remaining capacity of the battery, a remaining capacity swing, a health state deterioration of the battery with respect to the remaining capacity swing, a discharge depth, and a battery temperature.

The charge buffer control logic may include a power converter.

According to one aspect of the present invention, battery aging can be quantitatively analyzed by various operating scenarios based on benchmark programs.

According to one aspect of the present invention, a super capacitor is added as a charge buffer to mitigate aging of the battery without reducing system performance when the battery is connected to a power supply that supplies peak power .

1 is a configuration diagram of a portable electronic device according to an embodiment;
2 is a configuration diagram of a portable electronic device according to another embodiment;
3 is a configuration diagram of a portable electronic device according to another embodiment;
4 is a graph illustrating the current profile for gaming workload in a fully charged battery in accordance with one embodiment.
5 is a graph illustrating the overall discharge profile for a game workload according to one embodiment.
6 is a graph illustrating a battery SOC profile for a game workload in a 25% charged battery in accordance with one embodiment.
7 is a graph illustrating a battery remaining capacity profile during charging of a battery according to an embodiment.
8 is a graph illustrating battery current and battery voltage profile during charging of a battery according to one embodiment.
9 is a graph illustrating a usage profile according to one embodiment.
10 is a graph illustrating a battery current profile with a high workload while the remaining battery capacity is approximately 25% in accordance with one embodiment.
FIG. 11 is a graph showing a voltage profile of a supercapacitor in place of a battery when a game benchmark program according to an embodiment is performed. FIG.
12 is a graph showing a minimum amount of capacitance for reducing the deterioration of the remaining battery capacity according to an embodiment.
13 is a graph showing a voltage profile of a super capacitor replacing a battery when performing a game benchmark program according to an embodiment;

In the following, embodiments will be described in detail with reference to the accompanying drawings. Like reference symbols in the drawings denote like elements.

Various modifications may be made to the embodiments described below. It is to be understood that the embodiments described below are not intended to limit the embodiments, but include all modifications, equivalents, and alternatives to them.

The terms used in the examples are used only to illustrate specific embodiments and are not intended to limit the embodiments. The singular expressions include plural expressions unless the context clearly dictates otherwise. In this specification, the terms "comprises" or "having" and the like refer to the presence of stated features, integers, steps, operations, elements, components, or combinations thereof, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this embodiment belongs. Terms such as those defined in commonly used dictionaries are to be interpreted as having a meaning consistent with the contextual meaning of the related art and are to be interpreted as either ideal or overly formal in the sense of the present application Do not.

In the following description of the present invention with reference to the accompanying drawings, the same components are denoted by the same reference numerals regardless of the reference numerals, and redundant explanations thereof will be omitted. In the following description of the embodiments, a detailed description of related arts will be omitted if it is determined that the gist of the embodiments may be unnecessarily blurred.

When a power supply with a smaller capacity than the power requirement of a portable electronic device is used, the battery of the portable electronic device connected to the power supply can be exposed to aging. If the portable electronic device requires a high power demand, the power supply will not be able to meet this high power demand, so that additional power draws from the battery. This increases the aging of the battery.

For example, let's say that the shortfall between the power supply and the accumulated component power is 4W. If the battery is connected to an insufficient power supply under normal usage conditions, the aging becomes serious and the shelf lifetime of the battery may be reduced. Here, the shelf lifetime may be called a 'shelf life'. The storage period refers to the time it takes for the power of an unused battery to be stored in the battery but to fade to 80% of the total capacity of the initial battery.

In one embodiment, by using a supercapacitor as a charge buffer to reduce the burden on the battery, it is possible to alleviate aging of the battery when the portable electronic device is connected to the power supply.

To alleviate aging of the battery, a portable electronic device having a power supply having a supply power less than the peak power requirement of the portable electronic device in one embodiment may be considered. The maximum potential power consumption of a portable electronic device is estimated by the specification of the portable electronic device and the aging of the battery can be determined by comparing the estimated maximum potential power consumption with the power of the power supply have.

The portable electronic device can measure the current change of the built-in battery while various benchmark programs are being executed. Various representative usage scenarios can be created to look at battery aging in various situations.

The battery charging profile or the battery discharge profile can be converted to battery aging by a battery aging model based on the state of charge (SOC) swing and the average remaining capacity (average SOC).

While the portable electronic devices were operated by the power supply, the influence of the capacity of the supercapacitor was investigated. As a result, the supercapacitors of 10 mF, 1 mF, and 0.1 mF showed battery aging of 68.6%, 55.1% and 4.6% Respectively. In one embodiment, the size of the power supply for a portable electronic device that protects the battery from aging can also be reduced by buffering the charge by an appropriately sized supercapacitor.

Hereinafter, a configuration of a portable electronic device for alleviating aging of a battery connected to a power supply device according to an embodiment will be described with reference to FIG. 1 to FIG.

1 is a configuration diagram of a portable electronic device according to an embodiment.

1, a portable electronic device 100 according to one embodiment includes a charge buffer control logic 110, a charge buffer 120, a battery control logic 130, a battery 140, and a power control module 160, . The portable electronic device 100 may include, for example, a laptop computer, a notebook computer, a smart phone, and the like. 1 may be understood as a signal (or a control signal) to be exchanged with the power control module 160.

The charge buffer control logic 110, the charge buffer 120, the battery control logic 130, and the battery 140 may be coupled together via a DC bus 170 with a load 150.

The charge buffer control logic 110 controls the charging and discharging of the charge buffer 120. The charge buffer control logic 110 may comprise a power converter.

The charge buffer 120 buffers the charge. The charge buffer 120 may comprise, for example, electric double layer capacitors, i. E., A super capacitor. Alternatively, the charge buffer 120 may be an electrolytic capacitors.

The capacity of the charge buffer 120 may be determined based on at least one of the instantaneous power capacity of the average power capacity battery 140 of the power supply 50 and the peak power demand of the portable electronic device 100. [ The average power capacity of the power supply 50 can be understood as the power capacity that the power supply 50 can supply on average. The instantaneous power capacity of the battery 140 can be understood as the amount of power that can be output from the battery 140 within a predetermined reaction time.

The capacity of the charge buffer 120 is determined by the average remaining capacity of the battery 140, the remaining capacity swing, the deterioration of the state of health (SOH) of the battery with respect to the remaining capacity swing, the Depth of Discharge (DOD) ≪ RTI ID = 0.0 > temperature. ≪ / RTI > The remaining capacity of the battery 140 can be understood as the ratio of the available charging capacity of the battery 140 to the maximum available charging capacity of the recharged battery 140. [ The remaining capacity can be expressed as, for example, 100% when the battery capacity is full, and 0% when the battery capacity is exhausted. The discharge depth is an alternative measure of the remaining capacity of the battery. The (electrostatic) capacitance of the charge buffer 120 may be, for example, 5 mF to 10 mF.

The battery control logic 130 controls the charging and discharging of the battery.

The battery 140 supplies power to the portable electronic device 100. The battery 140 may be a lithium ion battery.

The power control module 160 determines that the portable electronic device 100 is operated by the power supply 50 of the external power supply 50 and the power supply is insufficient for the peak power requirement of the portable electronic device 100 , And controls the battery control logic 130 to block power from being drawn from the battery 140. The power control module 160 also controls the charge buffer control logic 110 to discharge the charge stored in the charge buffer 120.

The power capacity of the power supply 50 may be designed based on the average power consumption of the portable electronic device 100. [ The average power consumption of the portable electronic device 100 may be less than the peak power requirement of the portable electronic device 100. [

The power control module 160 may control the charge buffer 120 to be charged prior to the battery 140 if the power supply of the power supply 50 is greater than the peak power requirement of the portable electronic device 100. [ Lt; RTI ID = 0.0 > 110 < / RTI >

The power control module 160 measures at least one of voltage and current supplied to the load 150 and determines whether the power supply of the power supply 50 is on the basis of at least one of the measured voltage and the current, It is possible to judge whether or not the peak power demand of the mobile station is insufficient. The load 150 may be, for example, electronic circuits.

2 is a configuration diagram of a portable electronic device according to another embodiment.

2, a portable electronic device 200 according to one embodiment includes a charge buffer control logic 210, a charge buffer 220, a battery control logic 230, a battery 240, a DC-DC converter 250 A processor 260, and a power control module 270. [

The charge buffer control logic 210, the charge buffer 220, the battery control logic 230, the battery 240, the DC-DC converter 250, and the processor 260 may be coupled together via a DC bus 280 have.

The operation of the charge buffer control logic 210, the charge buffer 220, the battery control logic 230, the battery 240 and the power control module 270 are similar to those of the charge buffer control logic 110, charge buffer 120 ), The battery control logic 130, the battery 140, and the power control module 160, and therefore, the description of FIG. 1 will be referred to.

The DC-DC converter 250 may convert the DC voltage of the external power supply 50 that supplies power to the portable electronic device 200 to a DC voltage for the processor 260.

The processor 260 drives the portable electronic device 200. The processor 260 may drive various application programs, such as, for example, a game or an office, in the portable electronic device 200. The processor 260 may predict the power demand of the portable electronic device 200 based on the program being driven and may provide the power control module 270 with information related to the predicted power demand.

The power control module 270 determines whether the power supply of the power supply 50 is in the power demand of the portable electronic device 200 based on at least one of the voltage and the current output by the DC- It is possible to judge whether or not it is insufficient. The power control module 270 controls the battery control logic 230 to prevent the power from being drawn from the battery 240 when the power supply of the power supply 50 is insufficient for the power demand of the portable electronic device 200. [ And to control the charge buffer control logic 210 to discharge the charge stored in the charge buffer 220. [

3 is a configuration diagram of a portable electronic device according to another embodiment.

3, a portable electronic device 300 according to one embodiment includes a charge buffer control logic 310, a charge buffer 320, a battery control logic 330, a battery 340, a DC-DC converter 350 ), And a processor 360.

The charge buffer control logic 310, the charge buffer 320, the battery control logic 330, the battery 340, the DC-DC converter 350, and the processor 360 may be coupled together via a DC bus 370 have.

The operation of the charge buffer control logic 310, the charge buffer 320, the battery control logic 330, the battery 340 and the DC-DC converter 350 are similar to those of the charge buffer control logic 210, The operation of the buffer 220, the battery control logic 230, the battery 240, and the DC-DC converter 250 will be described.

The processor 360 drives the portable electronic device 300. The processor 360 may determine that the power output by the DC-DC converter 350 is less than the power requirement required by the program running on the portable electronic device 300, Logic < / RTI > 330 and charge buffer control logic 310. < RTI ID = 0.0 >

The processor 360 may control the charge buffer 320 to discharge the charge stored in the charge buffer 320 if the power output by the DC-DC converter 350 is less than the amount of power required by the program running on the portable electronic device 300. [ Control logic 310 and control battery control logic 330 to block power from battery 340 from being drawn.

The processor 360 may be configured to control the charge buffer 320 to be charged prior to the battery 340 if the power output by the DC-DC converter 350 is greater than the power requirement of the portable electronic device 300. [ Lt; RTI ID = 0.0 > 310 < / RTI >

The power capacity of the power supply 50 may be designed based on the average power consumption of the portable electronic device 300 and the average power consumption may be less than the peak power demand of the portable electronic device 300. [

Hereinafter, a method for alleviating battery aging will be described as an example of a notebook computer, which is one of portable electronic devices.

How to ease battery aging

In order to mitigate battery aging due to a small capacity power supply, i. E., A power supply where the power supply is insufficient for the peak power requirement of the portable electronic device, the processor or power control module of the notebook computer is powered by an external power supply The charging current and discharging current of the battery can be identified during operation.

In one embodiment, usage scenarios can be set up and appropriate workloads corresponding to usage scenarios can be selected. The battery currents (charge current and discharge current) can be measured while the workload is running and the notebook is connected to the power supply.

For example, battery aging such as battery health state (SOH) deterioration can be identified using a battery current profile. Here, the health state SOH of the battery indicates the state of the battery associated with the battery specification. The state of the battery can be understood as a state of capacity degradation of the battery. A drop in capacity results in a reduction in the life of the battery. The percentage of remaining life relative to the expected life of an unused battery can be used as a measure of the health state of the battery (SOH).

A general battery health state (SOH) degradation model considers only the periodic charging and discharging sequence. In one embodiment, the time series of the battery current profile may be converted to statistical data. This means that the average remaining capacity (average SOC) of the battery and the remaining capacity swing (SOC swing) do not change with time. The remaining capacity SOC can be understood as a ratio of the available charge amount of the battery to the maximum possible charge amount of the recharged battery.

In one embodiment, battery aging can be estimated from statistical data and health state (SOH) degradation models. Hereinafter, the study of battery aging will be described before determining the capacity of the super capacitor used as the charge buffer and examining the relaxation ratio of the battery aging against the capacity of the supercapacitor.

related research

Battery aging can be studied for batteries in different configuration situations. Batteries can be exposed to calendar aging even when they are not in use. The constant aging may vary depending on, for example, the storage conditions of the battery such as the remaining capacity (SOC) of the stored battery and the environmental temperature.

Considering the battery in use, the dependency of battery aging on different discharge C-rates is being studied. If additional temperature effects are considered, the discharge can be represented by an average remaining capacity and a remaining capacity swing instead of the C-rate.

An empirical data model can be used to predict battery degradation.

After the current of the battery is measured while the notebook computer is connected to the power supply, the current profile may be applied to the (aging) battery model and deterioration of the battery life may be induced. The aging model can be used repeatedly. The aging model may relate, for example, to health state (SOH) degradation, average SOC and battery temperature, etc., for a remaining capacity swing (SOC swing).

), 및 평균 잔존 용량(average SOC)으로부터 유도된 정규화 편차 (

)로 변환될 수 있다. From the test by the benchmark program, the measured time series profile can have any remaining battery capacity and mixed cycles of charging and discharging. Therefore, the time-series profile can be expressed by the following equation (1): average SOC (average SOC)

), And a normalization deviation derived from average SOC (average SOC)

). ≪ / RTI >

은 충전 및 방전되는 배터리의 m 번째 시간 간격(time interval)의 지속 시간(duration)이고,

는 모든 간격들의 총 지속 시간이다. here,

Is the duration of the m < th > time interval of the battery to be charged and discharged,

Is the total duration of all intervals.

The effective number of throughput cycles N expressed as Equation (2) below can be treated as microcycles.

는 배터리의 정격 충전 용량(nominal charge capacity)이고, i(t)는 시간 t일 때 배터리에서 흐르는 충/방전 전류를 나타낸다. here,

Is the nominal charge capacity of the battery, and i (t) is the charge / discharge current flowing in the battery at time t.

An increment (L ₁ ) of the lifetime parameter in a cycle describing the remaining capacity swing (SOC swing) and throughput can be given by Equation (3) below.

은 싸이클(cycle)의 시간(초)이고,

는 25℃ 및 50% 잔존 용량(SOC)에서 80%의 용량(capacity)에 대한 기대 예상 수명(expected shelf life)(초)이다.

는 25℃ 인 기준 배터리 온도(reference battery temperature)이고,

는 처리량(throughput)의 상수 계수이며,

는 방전 깊이(depth of discharge; DOD)를 위한 상수 지수(constant exponent)이다.

는 30℃의 상수 값으로 설정한 배터리 온도이다. here,

Is the time (in seconds) of the cycle,

Is the expected shelf life (in seconds) for a capacity of 80% at 25 ° C and a 50% residual capacity (SOC).

Lt; RTI ID = 0.0 > 25 C, < / RTI >

Is a constant coefficient of throughput,

Is a constant exponent for the depth of discharge (DOD).

Is a battery temperature set at a constant value of 30 ° C.

The discharge depth (DOD) is an alternative measure of the remaining battery capacity (SOC). The discharge depth 1 (or 100%) represents a fully discharged battery (a battery with a remaining capacity of 0%) and the discharge depth 0 (or 0%) represents a fully charged battery (a battery with a remaining capacity of 100%). In general, the discharge depth can exceed 100%, as the battery can be used a little more after the indicated capacity has been used. Since this situation can not be expressed as the remaining capacity, the remaining capacity of the battery can be expressed more clearly by using the discharge depth.

The average SOC and the increase (L ₂ ) of the lifetime parameter indicating the decrease in the lithium ion concentration can be expressed by Equation (4) below.

는 평균 잔존 용량(average SOC)에 대한 상수 계수이다. here,

Is a constant coefficient for the average remaining capacity (average SOC).

에 대한 노화의 증가는 아래의 <수학식 5>와 같이 나타낼 수 있다. While using the battery

Can be expressed as Equation (5) below. &Quot; (5) &quot;

는 온도가 매 10℃씩 증가함에 따른 붕괴율(decay rate)의 두 배이다. here,

Is twice the decay rate as the temperature increases by every 10 ° C.

The aging model can be extended to account for the idle times of the battery.

The battery is not used during the idle time, nor does the increase in aging due to the average SOC and the SOC swing occur. Therefore, only certain aging can be considered during idle time.

The lifetime parameter for the idle time of the battery can be calculated by Equation (6) below.

은 유휴 시간의 총량을 나타내고,

는 예를 들어, 15년으로 추정되는 저장 수명(shelf life)이다. here,

Represents the total amount of idle time,

For example, is a shelf life estimated at 15 years.

에 대한 노화량은 아래의 <수학식 7>과 같이 주어질 수 있다. During idle time

Can be given by Equation (7) below. &Lt; EMI ID = 7.0 >

또는

에 의해 증가될 수 있다. Depending on the use of a battery such as active or idle, the lifetime parameter L may be expressed as Equation (8) below

or

Lt; / RTI &gt;

Due to the dependence of L ₂ on the previous value (L ₁ ) of the life parameter (L), the chronological order of the sequence is important in the aging model. The life parameter (L) may have a value in the range [0, 1]. Here, 0 means a new battery, and 1 means a battery having no remaining capacity.

The battery used in one embodiment may be a lithium ion battery.

)는 30℃로, 기준 배터리 온도(

)는 25℃로 설정될 수 있다. It is not easy to obtain specific lifetime data for parameter pitting of a target battery. Thus, in one embodiment, and Kco = 3:66 x10 ^-5 to the discharge depth (DOD) 0.35 ~ 0.95, Kex = 0: 717, Ksoc = 0: 916 , and Kt = 0: 0693 A123 ANR26650M1A the lithium ion battery cells Can be used. Battery temperature (

) Is 30 ° C, the reference battery temperature (

) May be set to 25 占 폚.

In one embodiment, a hybrid energy storage device comprised of a battery and a supercapacitor may be used to mitigate aging of the battery connected to the power supply. Electric double layer capacitors, commonly known as supercapacitors, can be defined as the ratio of energy output to energy input. Supercapacitors can have excellent cycle efficiency reaching almost 100%. In addition, the supercapacitor has a high charge / discharge cycle period and does not cause aging.

Experiment settings

The following defines the usage profile using the benchmark programs used to look at the presence of discharge current when the notebook computer is connected to a power outlet and then calculate battery aging for the profiles.

Table 1 compares the specified maximum power consumption of two notebook computers (Lenovo T530-2359-A44, and Apple MacBook Pro) with the power available by the power supply.

In Table 1, for a Lenovo notebook computer, the specified power demand represents the case where the power provided by the power supply exceeds 4 W, and for the Apple notebook computer, the gap is greater 19 W . Hereinafter, the case where the power consumption of the notebook computer exceeds the power supplied by the power supply unit will be described.

Consider a Lenovo notebook computer that uses a 90W power supply and runs a heavy game workload while connected to a power supply. The current profile for the game workload may, for example, appear as in FIG.

FIG. 4 is a graph illustrating a current profile for a game workload in a fully charged battery according to an embodiment, and FIG. 5 is a graph illustrating an overall discharge profile for a game workload according to an embodiment. In Fig. 4, a negative current indicates discharge of the battery.

Figure 4 shows that the battery is exposed to a discharge current. This is a 10 second extract (part) of the current resulting in the discharge profile of the remaining capacity (SOC) of the battery of FIG.

Referring to FIG. 5, the battery can be discharged because the power supply can not provide a peak power demand. When the remaining capacity SOC of the battery is high, the remaining capacity SOC of the battery may be reduced to compensate for the power shortage. Hereinafter, the case where the battery has a low remaining capacity will be described with reference to FIG.

6 is a graph illustrating a battery SOC profile for a game workload in a 25% charged battery according to one embodiment.

For example, if the battery has a low residual capacity (SOC) of 25%, it still has discharge current, but the power supply can meet the average power consumption, as shown in FIG. This is important for building a usage profile.

When the battery is removed from the notebook computer and the same benchmark program is executed, the power control module can reduce the frequency of the processor and limit the performance of the notebook.

In one embodiment, the battery is discharged to 20% of the cut-off remaining capacity of the battery internal safety circuit to determine the usable capacity of the battery to be used at the 100% remaining capacity limit in the profile, The battery can be recharged by the external power supply while it is on.

FIG. 7 is a graph illustrating a battery remaining capacity profile during charging of a battery according to an embodiment. FIG. 8 is a graph illustrating a battery current and a battery voltage profile during charging of the battery according to an embodiment. Referring to Figures 7 and 8, the charging profile of the battery is shown.

In the graphics of FIGS. 7 and 8, the cut-off remaining capacity of 20% can be set to 0% remaining capacity. The remaining capacity profile can be measured for two categories of workloads.

In one embodiment, as an actual game workload, not only SimCity, an online 3D-based city planning simulation video game of EA Game Company but also Futuremark's benchmark programs 3DMark06, 3DMark08, Futuremark's Fishmarkworks (PCMark Work, Creative, and Work tests.

There is no significant difference in the category that affects the remaining battery capacity between workloads. In one embodiment, only two load characteristics of SimCity, which is an actual game, and PCMark Work, as an office workload, can be considered as game workloads. In one embodiment, the test can be run repeatedly and the workload and idle time for a predefined user type can be scheduled.

Aging result

The battery current is recorded for two different workloads, and an exemplary daily usage profile can be designed. The usage profile can be used to calculate the battery degradation of a new battery within 24 hours, assuming that the user performs the same operation throughout the year. In one embodiment, instead of performing an all day game or a benchmark program, the data may be iterated and sequenced to replay the notebook usage for a day.

The following [Table 2] shows four usage profiles, and Figure 9 shows the remaining battery capacity of four different use cases shown in [Table 2].

In Table 2, each represents 24 slots for 24 hours a day. In Table 2, the game workload is denoted by "g" and the office workload generated by the Office Workbenchmark program is denoted by "w". The end of idle time in [Table 2] guarantees full battery charge at the end of the daily profile.

9 is a graph illustrating a usage profile according to an embodiment.

Referring to FIG. 9, it can be seen that a discharge current is generated in the battery under an excessive workload, for example, a game workload.

When the aging model is applied to the usage profiles, battery degradation can be calculated. In one embodiment, assuming a new battery, the battery deterioration after one day can be calculated. Using this value (deterioration value after day) can lead to a reduction in the life span when the daily usage profile is applied to the notebook.

Table 3 below shows the total life span reduction in terms of one year for the four usage profiles, the battery deterioration during one day, and the constant aging in the absence of the battery.

In Table 3, the 100% lifetime represents a total shelf life of 15 years, whereas, for example, 17.95% reduces the battery capacity to 80% of its initial value after 2.69 years . As can be seen in Table 3, the life span reduction was 17.95% and 22.96%. Lt; / RTI &gt;

Assuming a shelf-life of 15 years, the battery capacity drops to 80% of its initial capacity after roughly three years, and the battery must be replaced. This result suggests that the battery ages due to the demand for high peak power that can not be met by the power supply. The above result may indicate that a shortage of 4W between the power supply's power supply and the maximum cumulative power demand of the notebook part causes battery aging. Hereinafter, aging mitigation using a capacitor will be described with reference to FIG.

10 is a graph illustrating battery current profiles with high workloads while the remaining battery capacity is approximately 25% in accordance with one embodiment. In Figure 10, the battery current profile is centered around zero (0). Therefore, the battery is charged and discharged.

In the scenarios considered, the easiest way to protect the battery from aging is to use a large power supply. However, users prefer small size and light weight power supplies. Table 4 below shows the results of comparing the sizes and weights of the power supply units (chargers) having different power supplies.

If the power supply is reduced to more than half its original weight, one third of the charger power is seen to have decreased.

The portable electronic device according to one embodiment can identify the current that is exposed to the super capacitor inserted into the charge buffer. To this end, it is assumed that when the notebook computer is plugged into an outlet, the remaining battery capacity is close to 100% or sooner than 100%. The charging protocol of the battery is a constant voltage (CV) mode, and the current to be charged is not the maximum.

To find a more realistic current to charge the supercapacitor, in one embodiment, the same game load can be performed at a remaining capacity of about 25%.

The battery is charged and discharged as shown in FIG. 10, while the accumulated battery remaining capacity (SOC) may slightly increase as shown in FIG. In other words, the power supply can satisfy the average power consumption even though the external power supply fails to supply sufficient power to the notebook computer.

In one embodiment, a User 2 profile with the deepest discharge depth (DOD) is selected and a CC-CV (constant current-constant voltage) charging protocol of a lithium ion battery is considered for a more realistic approach. Hereinafter, referring to FIG. 11, the relationship between the decrease in the remaining capacity of the battery and the minimum amount of energy stored in the supercapacitor will be described.

FIG. 11 is a graph showing a voltage profile of a supercapacitor in place of a battery when a game benchmark program according to an embodiment is performed.

Referring to Fig. 11, the minimum energy storage amount associated with a decrease in the battery remaining capacity per day is shown.

In one embodiment, in consideration of the fact that the terminal voltage varies substantially linearly depending on the remaining capacity of the battery, the setting for relieving the aging of the built-in battery based on the supercapacitor- The structure shown can be used.

The large swing at the terminal voltage of the supercapacitor can also result in a large change in the power converter efficiency connected between the supercapacitor and the DC bus. The efficiency of an external power supply (charger) can be influenced by input voltage, output voltage, and input current.

In one embodiment, for example, it is assumed that the external power supply is connected to the notebook so that the battery of the notebook is not discharged at the time when the notebook is not used at night. Therefore, the cold starting situation of the supercapacitors included in the notebook does not occur. In one embodiment, the lower boundary of the voltage level of the supercapacitor can be set to 10V, and the upper boundary can be set to 15V. Hereinafter, a method of finding a capacity of a suitable supercapacitor for reducing battery deterioration will be described with reference to FIGS. 12 and 13. FIG.

12 is a graph showing a minimum amount of capacitance for reducing a decrease in the remaining capacity of a battery according to an embodiment.

Referring to Fig. 12, there is shown the relationship between the capacitance of the supercapacitor and the decrease in the remaining battery capacity (SOC) in consideration of the efficiency of the power supply. The results of Figure 12 can be verified by replacing the battery of a laptop computer with a 120 mF supercapacitor with a voltage level of 15 V and performing a game benchmark program. In one embodiment, no additional charging circuit was used for verification.

The capacitance of the supercapacitor can be selected to be 10 times larger than the calculated minimum capacitance to buffer all the energy required in the portable electronic device and withstand the same losses.

In one embodiment, a benchmark program for various combinations of power supplies (chargers) with a battery (with battery), a battery removed (No battery), and a battery replaced with a supercapacitor (supercapacitor) (3DMark06) can be compared. The benchmark program (3DMark06) can use CPU and GPU extreme.

The performance results of the benchmark program (3DMark06) can be shown in [Table 5]. In Table 5, the power supply (charger) may have, for example, a supply power of 135 W, a supply power of 90 W, or may be unused.

Taking into account the small measurement inaccuracies in the performance results of the benchmark program, the results in [Table 5] show that replacing the battery with the same size supercapacitor does not lead to a reduction in benchmark results.

If one outlet is available, it can be seen that a power supply must be used to improve battery life and performance. Battery aging can be reduced because deep battery discharges at high currents are worse than low currents to meet peak demands. And, in terms of the performance of benchmark programs, the performance of real notebooks is better.

In one embodiment, the approximate size of the capacitor can be determined.

When adding some capacitance to compensate for the loss, the capacitance may have a range of at least 5 mF to 10 mF to prevent additional power from being drawn out of the battery. This range corresponds to the transition range from electrolytic capacitors to supercapacitors.

Table 6 below shows the price and size of electrolytic capacitors, supercapacitors, and alternative batteries. A number of supercapacitors of 10mF, 20mF, and 30mF can be used due to the rated voltage.

As shown in the following Table 6, the main difference between these electrolytic capacitors and the supercapacitors is price and size.

Electrolytic capacitors are cheap, but supercapacitors have a small size. These two options are much cheaper than buying a new battery. In one embodiment, a lifetime of 55% may correspond to 8.25 years.

FIG. 13 is a graph showing a voltage profile of a supercapacitor in place of a battery when a game benchmark program according to an embodiment is performed.

Referring to FIG. 13, there is shown a graph in which the voltage of the supercapacitor is measured when the battery is replaced by the supercapacitor after the battery is completely removed.

The battery charger can recognize the supercapacitor as a battery and charge the supercapacitor to a standard charge voltage of 12.7 V of the lithium ion battery. Thereafter, if a peak power demand occurs in the CPU and the GPU, and the power supply can not supply the peak power demand, power can be effectively supplied to the super capacitor as shown in FIG. Because the average supply power of the power supply is higher than the average power consumption required by the system, the supercapacitor is fully half-charged to 12.7V, and since the peak supply power of the power supply is lower than the peak power consumption required by the system, It can be clearly seen that the voltage of the supercapacitor drops.

According to one embodiment, the use of a supercapacitor that is used to meet a peak power demand can be a more cost effective solution than having the battery replaced after a short time by expelling power from the battery to promote aging.

In one embodiment, we have seen that a difference of only 4W between the power of the power supply (charger) and the power requirement of the notebook computer can lead to significant battery aging, for example, a lifetime corresponding to 22.96% of certain aging.

Battery discharge problems occur when a notebook computer is connected to a power supply, for high workloads such as games, and low workloads such as office work do not affect the battery. Therefore, in one embodiment, it is possible to reduce the size of the power supply device and provide a space in the notebook computer to use the supercapacitor as a buffer for the peak power requirement.

The shortage between the power provided by the portable electronic device and the power supplied by the power supply may result in accelerated aging. In summary, the battery ages even if the notebook is driven by a power supply whose capacity is less than the maximum power demand (in other words, the peak power requirement of the portable electronic device).

Reduced capacity power supplies have advantages, for example, in terms of cost, weight, form factor, etc., but this can lead to severe battery aging when the notebook is powered by a power supply . Thus, in one embodiment, the battery aging problem can be analyzed in the power supply with reduced capacity by measurement and simulation.

In one embodiment, the battery aging is quantified under actual usage scenarios composed of typical benchmark programs, and a supercapacitor is used to alleviate the aging of the battery. Experimental results show that the lifetime of a super capacitor with a capacitance of only 2mF is about three times higher than that of a capacitor without a capacitor.

The method according to an embodiment of the present invention can be implemented in the form of a program command which can be executed through various computer means and recorded in a computer-readable medium. The computer-readable medium may include program instructions, data files, data structures, and the like, alone or in combination. The program instructions recorded on the medium may be those specially designed and constructed for the present invention or may be available to those skilled in the art of computer software. Examples of computer-readable media include magnetic media such as hard disks, floppy disks and magnetic tape; optical media such as CD-ROMs and DVDs; magnetic media such as floppy disks; Magneto-optical media, and hardware devices specifically configured to store and execute program instructions such as ROM, RAM, flash memory, and the like. Examples of program instructions include machine language code such as those produced by a compiler, as well as high-level language code that can be executed by a computer using an interpreter or the like. The hardware devices described above may be configured to operate as one or more software modules to perform the operations of the present invention, and vice versa.

While the invention has been shown and described with reference to certain preferred embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. This is possible.

Therefore, the scope of the present invention should not be construed as being limited to the embodiments described, but should be determined by equivalents to the appended claims, as well as the appended claims.

50: Power supply
100: Portable electronic device
110: charge buffer control logic
120: charge buffer
130: Battery control logic
140: Battery
150: Load
160: Power control module
170: DC bus

Claims (20)

In a portable electronic device,
A battery for supplying electric power to the portable electronic device;
Battery control logic for controlling charging and discharging of the battery;
A charge buffer for buffering charges;
A charge buffer control logic for controlling charge and discharge of the charge buffer; And
Wherein when the portable electronic device is operated by a power supply of an external power supply and the supply power is insufficient for the peak power requirement of the portable electronic device, A power control module for controlling the charge control logic to control the charge buffer control logic to discharge charge stored in the charge buffer,
The portable electronic device. The method according to claim 1,
The power capacity of the power supply
Wherein the average power consumption of the portable electronic device is designed based on an average power consumption of the portable electronic device, the average power consumption being less than a peak power requirement of the portable electronic device. The method according to claim 1,
The power control module
And controls the charge buffer control logic and the battery control logic such that the charge buffer is preferentially charged with respect to the battery if the supply voltage is greater than the power demand. The method according to claim 1,
The power control module
Measuring at least one of voltage and current supplied to the load and determining whether the power supply is insufficient for the power demand based on at least one of the measured voltage and the current. The method according to claim 1,
The charge buffer
A portable electronic device comprising an electric double layer capacitor. The method according to claim 1,
The capacity of the charge buffer
The average power capacity of the power supply, the instantaneous power capacity of the battery, and the peak power demand. The method according to claim 1,
The capacity of the charge buffer
Based on simulation results based on at least one of an average remaining capacity (SOC) of the battery, a remaining capacity swing (SOC swing), a health state of the battery (SOH) deterioration with respect to the remaining capacity swing, a discharge depth (DOD) Wherein the portable electronic device is a portable electronic device. The method according to claim 1,
The capacity of the charge buffer
5 mF to 10 mF. The method according to claim 1,
The charge buffer control logic
A portable electronic device, comprising a power converter. The method according to claim 1,
A processor for driving the portable electronic device; And
A DC-DC converter for converting a DC voltage of an external power supply for supplying power to the portable electronic device to a DC voltage for the processor
Wherein the portable electronic device further comprises: 11. The method of claim 10,
The power control module
And determines whether the power supply is insufficient for the power demand based on at least one of a voltage and a current output by the DC-DC converter. 11. The method of claim 10,
The processor
Predicting the power demand based on a running program and providing the power control module with information related to the predicted power demand. In a portable electronic device,
A battery for supplying electric power to the portable electronic device;
Battery control logic for controlling charging and discharging of the battery;
A charge buffer for buffering charge;
A charge buffer control logic for controlling charge and discharge of the charge buffer;
A processor for driving the portable electronic device; And
A DC-DC converter for converting a DC voltage of an external power supply for supplying power to the portable electronic device to a DC voltage for the processor
Lt; / RTI &gt;
The processor
And controlling the battery control logic and the charge buffer control logic such that the insufficient power is not drawn out of the battery when the power output by the DC-DC converter is less than a power demand required by a program executed in the portable electronic device Lt; / RTI &gt; 14. The method of claim 13,
The processor
If the power output by the DC-DC converter is less than the power requirement required by the program running on the portable electronic device,
Controls the charge buffer control logic to discharge charge stored in the charge buffer and controls the battery control logic to block power from being drawn from the battery. 14. The method of claim 13,
The processor
And controls the charge buffer control logic and the battery control logic such that the charge buffer is preferentially charged more than the battery when the power output by the DC-DC converter is greater than the power requirement. 14. The method of claim 13,
The power capacity of the power supply
Wherein the average power consumption of the portable electronic device is designed based on an average power consumption of the portable electronic device, the average power consumption being less than a peak power requirement of the portable electronic device. 14. The method of claim 13,
The charge buffer
A portable electronic device comprising an electrical double layer capacitor. 14. The method of claim 13,
The capacity of the charge buffer
The average power capacity of the power supply, and the instantaneous power capacity of the battery. 14. The method of claim 13,
The capacity of the charge buffer
(SOC), a residual capacity swing (SOC swing), a deterioration of a battery health state (SOH), a discharge depth (DOD), and a battery temperature Lt; RTI ID = 0.0 &gt; 1, &lt; / RTI &gt; 14. The method of claim 13,
The charge buffer control logic
A portable electronic device, comprising a power converter.

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