鋰電池快速充電技術
Decryption of Quick Charging Technology
王信雄
立錡科技 / 系統開發中心
Dec. 3, 2015
your power partner.
王信雄
學術經歷
• 清華大學電機系 大學部 1981級, 博士班 1989 級畢業 1977 - 1989
• 美國Virginia Tech 電力電子中心訪問學者
1987 – 1988
• 清華大學電機系兼任副教授 (電力電子學)
1990 – 2006
主要企業經歷
• 英群企業協理、總工程師、電源事業處總經理
• 矩創科技總經理、技術長，創星(蘇州)科技董事長兼總經理
• 中強光電、聯德電子、達方電子電源研發副總經理
現職
• 立錡科技系統開發中心副總經理
2
your power partner.
Outline
 The Knowns and The Intuitive
 Power Architecture of Portable Devices
 Quick Charging Technology Evolution
 New Thinking for Quick Charge
 About Richtek
3
your power partner.
開關電源相關技術
電電電電
電電電電電
電電電電
電電電電
電電電電
電電電電電
電電電電
4
your power partner.
The Knowns and The Intuitive
5
your power partner.
Adaptor ? Charger ?
iPhone 4
iPad
your power partner.
5V / 1A
5V / 2A
6
AC-DC SPS : Single-Output Adaptor
Line Utility
EMI Filter
AC Input
· 1ϕ
· 2W / 3W
· 90Vac ~ 265Vac
PFC
Isolated
D2D
PFC
· Boost / Buck
· Bridgeless
· 1-stage Flyback
Isolated D2D
· Flyback
· LLC
· Forward
Cable
DC BUS
DC Output
· Fixed 5 ~ 24 V
Slim Type 90W NB Adaptor
NB / Phone / NC / Printer / Camera / Monitor
7
your power partner.
AC-DC SPS : Open-Frame Multiple Outputs
Line Utility
EMI Filter
AC Input
· 1ϕ
· 2W / 3W
· 90Vac ~ 265Vac
PFC
PFC
· Boost / Buck
· Bridgeless
Isolated
D2D
Cable
DC Multi-output
· Main O/P Fixed 12 ~ 24 V
· Standby 5V
· LV 3V3
Isolated D2D
· Flyback
· LLC
· Forward
Multiwinding Xmer
TV Power Supply with LED Board
Monitor / TV / DT PC / Medical / Industrial
your power partner.
8
USB-PD Power Profiles
Source Capabilities Organized as Profiles
PROFILE 0
Reserved
Hand-held devices,
Today’s peripherals
PROFILE 1
5V @ 2A
10W
Default start-up profile
Tablets, notebooks,
most peripherals
PROFILE 2
5V @ 2A, 12V @ 1.5A
18W
Thinner notebooks,
larger peripherals
PROFILE 3
5V @ 2A, 12V@ 3A
36W
Larger notebooks,
hubs, docks
PROFILE 4
5V @ 2A, 12V, 20V @ 3A
60W
Limit for Micro B/AB connector
Workstations,
hubs, docks
PROFILE 4
5V @ 2A, 12V, 20V @ 5A
100W
Limit for standard A/B connector
• Additional capabilities are possible as optional extensions to standard profiles9
your power partner.
Bi-directional Converters
Buck or Boost or Buck-Boost
Boost or Buck or Buck-Boost
Buck
Boost
BAT
BAT
• Power flow controlled by gate driving strategy.
• Increase design degree of freedom. (Role of energy provider/consumer)
10
your power partner.
Conversion Efficiency of Buck and Boost Converters
RT6217F ACOT Buck
RT8450A SR Boost
• Full-loaded maximum efficiency occurs at minimum difference
between input and output voltages.
• Inductor size is smaller when less voltage difference between input and
output voltage.
11
your power partner.
Low-Dropout Linear Regulators
IIN
VIN
IO
VDO
Control
Circuit
L
O
A
D
VO
Iq
• Low Dropout Voltage, VDO = VIN - VO (> 100 mV for PMOS)
• Efficiency, η 
VO  IO
VIN  (IO  Iq )
Loss, PL  VIN  (IO  Iq )  VO  IO
12
your power partner.
Thermal Consideration for LDO Regulator
VIN (V)
2.7 ~ 5.5
VDO (V)
@ IO = 1.5A
0.22
IO_MAX (A)
LP38500 (TI)
Iq (mA)
Tjmax (oC)
RθjA (oC/W)
@ IO = 1.5A
(recommended)
WSON 8
2
125
52.5
1.5
Working Condition : VIN = 5V, VO = 3.3V, IO = 1.5A, Ta = 25oC.
PL  5  (1.5  0.002)  3.3  1.5  2.551 (W)
Tj  52.5  2.551  Ta  159 (oC)
• Need additional heatsink or derating the output current.
If adjust VIN = VO+VDO = 3.52 V, then
PL  3.52  (1.5  0.002)  3.3  1.5  0.331 (W)
Tj  52.5  0.331  Ta  42.4 (oC)
• Much less power loss. Can handle higher current with same pkg.
your power partner.
13
Lithium-Ion Polymer Battery
Samsung Galaxy Note Edge
3,000 mAh, 1S1P, 3.85V, 4.4V max.
Lenovo X230T
5,200 mAh, 3S2P, 11.1V
• Capacity : 3,000 mAh ( 10,800 Coulomb)
(Charge, Q, unit : 1 Coulomb = 1 Asec)
• Nominal Working Voltage : 3.7 ~ 3.85 V
14
your power partner.
Lithium-Ion Polymer Battery
Voltage-Current Characteristics
3600
IBAT
Ccapacity
Battery
Rself-discharge
VSOC
RSeries
RTrans_S
RTrans_L
0.074
0.047
0.05
CTrans_S
704
CTrans_L
4475
VOC(VSOC)
Battery Lifetime
VBAT
IBAT
840mAh Polymer Lithium
• Can be imaged as a big capacitor with several thousands Farad.
• Internal resistance : 150 ~ 300 mΩ typically.
• SoC (State of Charge) : the equivalent of a fuel gauge for the battery
pack. Unit : % ((0% = empty; 100% = full).
15
your power partner.
Lithium-Ion Battery Charger
Fast CC
CV
EOC
Ifcc
4.35
ΔQ
Battery Voltage (V)
Charging Current (A)
Trickle CC
3.3
Itcc
C/40
Charging Time
•
•
•
•
Trickle charge (0.1 C) when battery deeply discharge. (VBAT < 3.3 V)
Fast Constant Current charge (0.5 ~1.5C) when 3.3V < VBAT < 4.35V.
Constant Voltage charge when VBAT = 4.35V.
Highest Charge Rate depends on capability of charger (adaptor /
charger) and internal resistance of battery.
your power partner.
16
Charging Curves
2,000 mAh
C rate vs. Battery voltage
4.5
3
C rate vs. SOC(%)
100
3
90
3.6
SOC(1.2C)
80
1.8
1.2
2.5
SOC(1.0C)
70
SoC (%)
3.9
2.4
ICHG (A)
VBAT (V)
4.2
60
SOC(0.8C)
50
SOC(0.6C)
40
SOC(0.4C)
2
1.5
1
30
3.3
0.6
ICHG (A)
Voltage(1.2C)
Voltage(1.0C)
Voltage(0.8C)
Voltage(0.6C)
Voltage(0.4C)
Current(1.2C)
Current(1.0C)
Current(0.8C)
Current(0.6C)
Current(0.4C)
20
0.5
10
3
0
0
0.5
1
1.5
Time (Hr)
2
2.5
3
0
0
0
0.5
1
1.5
Time (Hr)
2
2.5
3
• During CC charging, the SoC linearly increases. Q(t )   i (t ) dt  ICHG  t
However, battery voltage increases nonlinearly.
• Taking long time for CV charging to fully charge.
17
your power partner.
1C (2A) CC/CV (4.35V) Charging Profile
2.5
100
4.5
10
4.3
8
4.1
6
3.9
4
3.7
2
2
80
60
50
1
40
SoC (%)
IBAT A)
1.5
VBAT (V)
70
30
0.5
20
Charging Power (W)
90
10
0
0
0
0.5
1
1.5
2
3.5
0
0
0.5
Time (Hr)
1
1.5
2
Time (Hr)
• 35 min. CC then CV for specific battery.
• 48 min. reach 80% SoC, 115 min. for 100%
• Peak charging power : 8.7W
18
your power partner.
1.2C CC/CV (4.35V) Charging Profile
Charging Curve with 1.2C
100
4.5
90
4
80
3.5
RINT = 180 mΩ
VOC
70
3
60
SoC
1.2C
2.5
50
2
SoC (%)
IBAT (A), VOC (V)
5
40
1.5
30
IBAT
1
20
0.5
10
0
0
0
0.34 0.5
0.73
1
1.5
2
Time (Hr)
• 20 min. CC then CV for specific battery.
• 45 min. reach 80% SoC, 105 min. for 100%
19
your power partner.
Measurement from RT9460 with Various TAs
• The closer between VIN and VBAT,
the higher efficiency is.
• AICR / MIVR : The capability
limitation of adaptor.
• Thermal problem due to internal
resistance limits C-rate charge.
20
your power partner.
AnyVoltTM / AnyCurrentTM Technology
21
your power partner.
V-I Characteristics for AnyVolt and AnyCurrent
VO
Cable Drop
VO_PCB END
VO_CABLE END
Permissible
output region
VO_MIN
Foldback
(Loss Regulation)
ICC
IO_MAX IO
• In addition to output voltage, more load information are sensed.
Then output voltage or current can be programmed to optimize the
system performance.
22
your power partner.
AnyVolt & AnyCurrent
Advantages
1. Automatic cable compensation; Programmable output voltage /
output current from load side by 9-bit (512 step) resolution.
2. If together with linear charger, dropout can be precisely
controlled. Hence, less power consumption and less thermal
problem.
3. If together with switching charger, efficiency optimization can be
done by adjusting TA voltage.
4. CC/CV charging directly from TA is possible . (Conventional
charger can be saved)
your power partner.
AnyVolt & AnyCurrent
Disadvantages
1. Higher cost due to complicated design (Digital communication
and ADC/DAC, …)
Technical Barrier
1. Loop stability for much wider operating area (input voltage,
output current, output voltage) becomes problematic. Adaptive
gain control is inevitable.
2. Synchronous Rectification becomes crucial if direct charging from
TA to battery. (Low-Voltage, High-Current)
3. Advanced control strategies such as CCM / QR DCM) are forced
required for higher efficient conversion and higher power density.
your power partner.
CC and CV Control
+VOUT
To Primary
R2
2.5V
R4
R3
VOUT
ILOAD
C1
OP1
VCNTL
Load
C3
OP2
GND
ICNTL
VSENSE
RSS
R5
R1
R6
-VOUT
• Two-OPA configuration is widely adopted for decades, especially
for constant current lighting applications.
25
your power partner.
Cable Drop Compensation
Conventional Remote Sensing
VO+
10Ω
VIN
Power Supply
10Ω
RCABLE
Fast Response !
VS+
L
O
VLOAD
A
D
VSVORCABLE
AnyVolt / AnyCurrent Technology
VO+
10Ω
VIN
Power Supply
RCABLE
D+
Load voltage
sensing &
Voltage adjust
commend
D-
L
O
VLOAD
A
D
Programmable !
Flexible !
VORCABLE
your power partner.
26
Programmable Output Voltage
RT7800
AnyVoltTM
Constant-Voltage
Control
VIN
DC-DC PWM
Converter
VOUT
VREF
FB
R1
DAC_CV
9-bit D/A
Converter
IDAC
IDAC
R2

R 
VOUT   1  1  VREF  IDAC  R1
R2 

• Resolution depends on D/A converter. (3.6V to 20V, 30mV/step)
27
your power partner.
RT7786 + RT7027 Solution for AnyVolt and AnyCurrent
Advanced Features :
Flyback Controller RT7786 (SOP-8)
•
•
•
•
CCM / Valley Switching DCM Operation
Adaptive Loop Stability Control
Adaptive OCP
External OTP
PD Controller RT7207 (WQFN-24L)
•
•
•
•
CV Control (3.2V~20V with 35mV/step) and CC Control (10mA/step)
Allow SR Operation in both CCM and DCM
Adaptive Output OVP
USB PD Type C Compliant for BMC Communication
Bi-phase Mark Coding
your power partner.
RT7786 + RT7027 Solution for AnyVolt and AnyCurrent
• Up to 75W. USB-PD adaptor : Vout = 3V~20V Iomax=3A
• Meet DoE lot 6, CoC Tier-2 at 5V/12V/20V efficiency regulation.
• No load input power < 30mW (HV start-up)
your power partner.
Efficiency and Power Density
AVG EFF.
SPEC
115V
230V
5V / 3A
81.84%
89.1%
87.69%
12V / 3A
88.3%
91.99%
92.02%
20V / 3A
89%
92.45%
93.07%
* CoC Tier-2 Regulation
55 x 50 x 25 mm (PCB only);
(0.9 W/cm3, 14 W/in3)
30
your power partner.
Quick Charging Technology
31
your power partner.
Battery Charger for Mobile Phone / Tablet
TA
Conventional Adaptor
VO = 5V or
VO = 5V / 9V / 12V
Cable
Charger
Battery
Linear Charger
Rcable
Li-Ion Battery
PD AnyVolt Adaptor
VO = 3.6V ~ 20V
IO = 0 ~ 5A
Reservoir
Switching Charger
(Buck Type)
Dam
(V-I Controller)
Big Container
• Limitations : Power, Connector, Wire Drop, Thermal, Safety
32
your power partner.
Charging a Battery
Adaptor
AC à 12/9/5 V
VOUT  IOUT
Charger IC
Battery
12/9/5 V àCC/CV
to Battery
CC/CV Controller
from Charger
VBAT  ICHG
• ICHG_MAX depends on thermal and battery Characteristics.
• IOUT_MAX depends on adaptor capability and connector resistance.
• Loss on charger IC is very critical and to be removed.
33
your power partner.
Quick Charge Approaches - I
Samsung AFC
Qualcomm QC 2.0
MediaTek PumpExpress
TI MaxCharge
Mi Quick Charge
OPPO VOOC
LVHC
HVLC
your power partner.
獨孤求敗 !
34
Fast Charge Approaches - II
Connector type
Micro-USB
Type C
Protocol
Communication
Qualcomm QC2.0
Proprietary Protocol
Samsung AFC
ASUS (QC2.0/3.0)
D+/DMTK PumpExpress/+
ID (Lenovo)
Xiaomi Mi-Quick Charge
VBUS
OPPO VOOC
TI MaxCharge
USBPD
Standard Protocol CC1/CC2 for PD-Type C
USBPD-Type C
D+/DQuick charge protocol
Samsung
AFC
Communication
Channel
D- w/
D+ =
contant 0.6V
Qualcomm
QC2.0
D+ /D-
MTK
PE+
VBUS
ASUS
AQC2.0
USBPD
VBUS
VBUS
(Type-A & B)
USBPD
-Type C
CC pin
ASUS
AQC3.0
OPPO
5Pin:D+ /D- by
I2C
D+ /D7Pin:SCL/SDA
35
your power partner.
State-of-Art Quick Charge Products
品牌型號
魅族 MX5
魅族 PRO 5
小米 4C
小米NOTE
小米NOTE頂配
電壓 (V)
9
12
9
9
9
電流 (A)
1.85
1.74
1.1
1.1
1.5
功率 (W)
17
21
10
10
13.5
品牌型號
三星 S6
三星 NOTE 5
華為榮耀7
索尼 Z3+
OPPO R7
電壓 (V)
9
9
9
9
4.7
電流 (A)
1.5
1.7
1.5
1.3
3.7
功率 (W)
13.5
15
13.5
12
17.5
• Most likely QC 2.0 technology (High-V Low-I)
• OPPO adopts Low-V High-I
• Speed of charging depends on power capability
36
your power partner.
Conventional Battery Charger
Conventional Adaptor
or USB
VO = 5V / 0.5A, 1A
VTA
Rcable
VIN
Linear Charger
0.5C
ITA = IIN
VBAT
Li-Ion Battery
~ 1,000 mAh
ICHARGE
• Low Battery Capacity ( 1,000 ~ 1,500 mAh)
• Power Source Limit , Low Charge Rate ( 0.5C ~ 0.7C)
• Charger Loss : PL,CHR  (VIN  VBAT )  ICHARGE
• Charging Time > 2 hrs
37
your power partner.
Quick Charge 1.0
Conventional Adaptor
or USB
VO = 5V / 1.5A / 2A
VTA
Rcable
VIN
Linear Charger
0.6C
ITA = IIN
VBAT
Li-Ion Battery
~ 2,000 mAh
ICHARGE
• Battery Capacity ( 1,500 ~ 2,000 mAh)
• Power Source Limit, Low Charge Rate ( 0.5C ~ 0.7C)
• Charger Loss : PL,CHR  (VIN  VBAT )  ICHARGE
• Charging Time > 2 hrs
38
your power partner.
Quick Charge 2.0
Conventional Adaptor
VO = 9V, 12V / 1.5A
VTA
Rcable
VIN
Switching Charger
0.8C
ITA = IIN
VBAT
Li-Ion Battery
~ 2,500 mAh
ICHARGE
• Battery Capacity ( 2,000 ~ 3,000 mAh)
• Low Charge Rate ( 0.7C ~ 1C)
• High Voltage Low Current for Adaptor and Charger
• Limitation : Micro USB (2A), Cable Drop, AICR, MIVR
• Charging Time : Around 1 hrs (80% SoC)
39
your power partner.
Quick Charge 3.0 ?
QC 3.0 : Intelligent Negotiation for Optimum Voltage (INOV) with Type-C USB.
PD Adaptor
VO = 3.6V ~ 20V / 3A
VTA
Rcable
VIN
Switching Charger
1.2C
ITA = IIN
VBAT
Li-Ion Battery
~ 3,000 mAh
ICHARGE
• Battery Capacity ( 2,500 ~ 3,000 mAh)
• High Charge Rate ( 1C ~ 1.5C) (Battery Improved)
• Trickle / Constant Current / Constant Voltage Charge
• Limitation : AICR, MIVR
• Charging Time : Around 0.6 hrs (80% SoC)
40
your power partner.
OPPO TA and Battery Pack
(Low Voltage High Current)
5V / 4.5A
2,800 mAh / 3.8V
41
your power partner.
OPPO VOOC Charging Profile (2,800 mAh Battery)
Mobile Phone is power on.
42
your power partner.
AnyVoltTM / AnyCurrentTM for Battery Charger
Switching Charger
< 0.5C
AnyV / AnyA Adaptor
VO = 3.6V ~ 20V
IO = 5A
VTA
Rcable
ITA = IIN
VIN
VBAT
ICHARGE
Li-Ion Battery
~ 3,000 mAh
IFAST CHG = 1.5C
• High Battery Capacity ( > 3,000 mAh)
• High Charge Rate (up to 1.5C) thru wall adaptor directly
• Trickle Charge goes thru small charger
• Bidirectional Buck / Boost charger for USB OTG
• USB-PD or proprietary protocol / Type C
• Highest efficiency and highest charging speed
• Charging time : Around 0.5 hrs (75% SoC)
your power partner.
43
your power partner.
thank you.
立錡科技股份有限公司
王信雄
立錡科技
Dec. 3, 2015
your power partner.
RICH
+
TEK
46
your power partner.
立錡科技
 成立時間：西元1998年09月
 資本額：NT$14.9億
 員工人數：全球 1000人
 總部地點：竹北市台元科技園區
 國內第一家股票上市專業類比IC設計公司(2003.10)
 產品應用：電腦、通訊、消費性、車用等 4C 電子產品
台灣類比 IC 設計產業第一名
全球電源管理 IC 設計產業 Top 5
47
your power partner.
立錡歷年營收
14,000
12,000
10,000
8,000
6,000
4,000
2,000
0
Net Sales (NT$M)
2000
350
2001
670
2002
1,104
2003
2,011
2004
2,242
2005
2,684
2006
4,296
2007
6,062
2008
6,841
2009 2010 2011 2012 2013 2014
8,033 11,618 10,683 11,019 10,728 11,930
48
your power partner.
World’s No. 5 Power Management IC Supplier
2013
Rank
2014
Rank
Company
Name
1
1
Texas Instruments
2
2
3
2013
Revenue
2014
Revenue
Percentage
Change
2014
Share (%)
2,085
2,464
18%
24%
Maxim Integrated
875
929
6%
9%
3
Linear Technology
728
804
10%
8%
5
4
ON Semiconductor
418
414
-1%
4%
7
5
Richtek Technology
361
396
10%
4%
6
6
Sanken
374
378
1%
4%
4
7
STMicroelectronics
429
375
-13%
4%
8
8
Power Integrations
334
346
4%
3%
9
9
Intersil
305
297
-3%
3%
10
10
Fairchild Semiconductor
232
255
10%
2%
Others
3,675
3,825
4%
36%
Total Market
9,816
10,483
7%
100%
(Millions of $US)
Source: Gartner's Annual Market Share Compilation (April, 2015)
your power partner.
49
電源管理積體電路台灣第一
電源管理IC公司
2014年營業額
(KNTD)
1
立錡
11,930,118
2
致新
3,941,557
3
茂達
3,486,008
4
F矽力
3,2,72,732
5
F昂寶
2,983,167
6
尼克森
2,366,018
7
聚積
2,147,221
8
富鼎
2,061,113
50
your power partner.
核心競爭力
• 高素質經驗豐富的研發人才；
• 具類比與數位電路基礎與先進創新技術能力；
• 具效能指標領先的完整電源管理積體電路產品線；
• 最短交付期的完整電源管理解決方案；
• 穩定快速反應的製造能力，提供最低成本結構的產品；
• 全面品質檢討，提供最快的故障分析與退運流程。
51
your power partner.
技術與營業實績
1. 0.6μ/0.35μ/0.25μ/0.18μ 低/中/高壓製程驗證能力；
2. 超過800件的專利通過與完整類比IP建立；
3. 完整豐富的電源管理產品線，每月銷貨2.5億顆；
4. 高品質紀錄：年平均退貨率 0.5dppm；
5. 產品毛利近40%，每年獲利超過一個資本額。
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your power partner.
電源管理積體電路設計核心技術
 半導體製程技術 --- 虛擬晶圓廠
 類比為主、數位為輔的半導體電路設計
 電力電子(能源電子) 系統領域知識
電力電子應用技術
半導體制程技術
類比IC設計技術
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your power partner.
Richtek Product Categories
Regulator
Lighting
• Backlight Driver
• Flash LED Driver
• AMOLED Driver
• LED Lighting
Audio
your power partner.
• LDO
• DC/DC
• Charge Pump
• AC/DC
• SPK Amp
• HP Amp
• Subsystem
• CODEC
Battery
Management
PMIC
Others
• Linear Charger
• Switching Charger
• OVP
• Fuel Gauge
• TFT LCD
• DSC
• Mobile Handset
• MP3 / USB Modem
• MUIC / Mini ABB
• USB2.0 HS PHY
• Reset IC
• Motor Driver
• USB Power S/W
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your power partner.
thank you.
56
your power partner.
Battery and Charger Characteristics
2,000 mAh
Voc vs. SOC(%)
4.4
5
4.2
4
SoC(%) =100
SoC(%) = 80
4
Time (Hr)
Voc (V)
Charging Time vs. C Rate
Current(1.2C)
3.8
Current(1.0C)
3
SoC(%) = 60
2
Current(0.8C)
3.6
Current(0.6C)
1
Current(0.4C)
3.4
0
10
20
30
40
50
SoC (%)
60
70
80
90
100
0
0
0.2
0.4
0.6
0.8
1
1.2
1.4
C Rate (C)
• Open Circuit Voltage VOC of Battery is function of SoC. Difficult to
model mathematically.
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your power partner.
Step Current and CV Charging
C rate vs. SOC(%)
C rate vs. Battery voltage
4.5
3
100
3
90
3.6
3.3
1.5
1
0.5
2.5
SOC(1.2C)
SOC(1.0C)
SOC(0.8C)
SOC(0.6C)
SOC(0.4C)
SOC(Step current)
Current(1.2C)
Current(1.0C)
Current(0.8C)
Current(0.6C)
Current(0.4C)
Step current
70
60
50
40
30
2
1.5
ICHG (A)
2
SoC (%)
3.9
80
ICHG (A)
VBAT (V)
2.5
Voltage(1.2C)
Voltage(1.0C)
Voltage(0.8C)
Voltage(0.6C)
Voltage(0.4C)
Voltage(Step current)
Current(1.2C)
Current(1.0C)
Current(0.8C)
Current(0.6C)
Current(0.4C)
Current(Step current)
4.2
1
20
0.5
10
3
0
0
0.5
1
1.5
Time(h)
2
2.5
3
0
0
0
0.5
1
1.5
Time (Hr)
2
2.5
3
• From charging speed (SoC= 80%) point of view, there is no benefit
for step current charging. (The area below charging current is ΔQ)
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your power partner.