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Li-Polymer Battery Li-Polymer Battery PacksPacks for for E-bikesE-bikesLi-Polymer Battery Packs for E-bikes

GM BGM BATTERIESATTERIES GM BATTERIES

Anthony LuGUANGZHOU MARKYN BATTERY CO., LTD

Dr. Quansheng Yang R&D Dept. Wuhan Factory 752,

Presentation

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Safety Test

Impact

Safety Test

Needle stabbed

DROP

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Main CharacteristicsMain Characteristics Main Characteristics

Main Characteristics – High energy density– Light in weight– Long cycle life– Discharge current can be adjusted at drivers

wishes, providing a smooth driving– High safe characteristics– Compliant to pollution-free

Of Lithium polymer Battery Packs

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Temperature Characteristics for E-bikesOf 24V/12Ah Lithium polymer Battery Packs

Di scharge t i me/ mi n

Volt

age\

v

20

21

29

25

℃

℃℃

℃℃

Charge: CC/ CV 2A, 29. 4V× 8h, 25℃Di scharge: 6A cut off at 21V

30

5

30

29

21

25

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Charge: CC/ CV 2A, 29. 4V× 8h 25℃Di scharge: Cut off at 21V

Capaci ty rate%

Discharge Characteristics for E-bikesOf 24V/12Ah Lithium polymer Battery Packs

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Charge: CC/ CV, 29. 4V(1CA)× 3. 5hrs, 25℃Di scharge: Constant current 1CA, 25℃

Number of cycl es

Capa

city

rat

ion(

%)

Cycle life Characteristics for E-bikesOf 24V/12Ah Lithium polymer Battery Packs

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Since establishment of EV battery R&D in 2003, our engineers have succeeded in developing Lithium Polymer battery packs for RC hobby and mobile tools, and at the end of the same year, we began to manufacture emergency power supply system, Back-up for GPS or radio communication equipment, the sizes including 110V50Ah,110v100Ah, etc.

History of Lithium Polymer Battery Packs for EVHistory of Lithium Polymer Battery Packs for EV History of Lithium Polymer Battery Packs for EV

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History of Lithium Polymer Battery Packs for EVHistory of Lithium Polymer Battery Packs for EV

Battery packs for E-bikes is an important development project and developing direction, experienced 3-year research and test in actual application.

History of Lithium Polymer Battery Packs for EV

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History of Lithium Polymer Battery Packs for EVHistory of Lithium Polymer Battery Packs for EV

We began to put our battery packs into applications 3 years ago, and preliminarily found all the data meets the demand, then we marketed the packs at the same year, but customers feedback was not very optimistic, the main problem is PCB , Emails below gave us the feed-backs on typical problems:

History of Lithium Polymer Battery Packs for EV

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Customers letters

Dear GMB,we have made a lot of tests on your battery. What I can say is that your electrochemistry is

good, the battery have good performance in term off capacity and cycling. Butt there is some trouble with this points:

1) the over discharge electronic circuit is very sensible to temperature and have too high serial resistance

2) the mechanical fixation and insulation of the pcb is made of cardboard and paper, it is not compatible with safety

3) the charger pcb was broken , don't use backelite PCB 4) the charger connector of the battery is not short circuit protected and directly connected to

the battery 5) the individual battery are not well mounted also, there is just some think like melted candle

to maintain all components (Mr. Mr. Decourt from ICMCB)

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Customers Feedback

Dear Neil, How are you doing? It has been a long time we talked. And the next summer is here. It gives me good moments to use my e-bikes! Good and bad news: Good:My E-bike still runs fine with your 24V battery-pack. Medium Good:The 36V Battery pack also runs. (But very weak. After discharging 3Ah the voltage of one cell is below 3V!) Bad: I don't use your charger anymore. I read on a discussion-group in the Internet, that the cells life much longer, when only charged up to

4.1 V! (What I did: I made a prallel-connector and charge all 7-cells in parallel with a regulated powersupply 3A; this means maximum 21hour charging; for 7x10Ah) It works perfect!

I did this out of FEAR of EXPLOSION (!) after the other 24V battery-pack which I have from you, suddendly looked like blown. I am not joking! When I carefully opened it, I saw why: 2 cells looked like a balloon!!! The voltage of this (3parallel) Cellpack was 1.5V. The confusing thing is, that this happened only by storage it! I DID NOT USE THIS BATTERYPACK!! I only measured the voltage when I received it. (It was between 4.1 and 4.3V each Cell)

What do you think about that? Have you heard of similar problems?I would appreciate if you could send 2 Cell-packs (of 3 Cells) So I could repare the broken battery-pack!Best Regards,Philipp 

Customers Feedback

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The evolving 24V10Ah for e-bike

Mail Characteristics of Li-ion Polymer battery Pack

Nominal Energy: 240 WhrsNominal Voltages:24V (7 cells)

Continuous discharge: 1C (continuous full speed)Peak discharge: 3C for 1 minutes

Energy Density: > 130 Whr/kg at 1CLifetime: > 300 cycles at 70% DOD

Temperature range: -20°C to 50°C ambientDimension:42*120*270(mm)

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Temperature Characteristics for E-bikesOf 24V/12Ah Lithium polymer Battery Packs

Di scharge t i me/ mi n

Volt

age\

v

20

21

29

25

℃

℃℃

℃℃

Charge: CC/ CV 2A, 29. 4V× 8h, 25℃Di scharge: 6A cut off at 21V

30

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Charge Characteristics for E-bikes

Charge t i me/ h

Charge current

Charge: 2A, 29. 4V× 8h, 25℃

Curr

ent/

A

Charge vol tage

Volt

age/

V

21

20

25

29

30

Of 24V/12Ah Lithium polymer Battery Packs

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Capaci ty rate%

Charge: CC/ CV 2A, 29. 4V× 8h 25℃Di scharge: Cut off at 21V

20

25

21

29

30

Discharge Characteristics for E-bikesOf 24V/12Ah Lithium polymer Battery Packs

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Charge: CC/ CV, 29. 4V(1CA)× 3. 5hrs, 25℃Di scharge: Constant current 1CA, 25℃

Number of cycl es

Capa

city

rat

ion(

%)Cycle life Characteristics for E-bikes

Of 24V/12Ah Lithium polymer Battery Packs

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BMS Characteristics

– Scalable temperature control

– Ultra low standby current for long shelf live (<100mA)

– Separet Current-Switch for Charging and Discharging using Power MOSFET’s

– Passive Cell balancing System during charge

– Can Cut off circuit when the battery is in over-charge, over-discharge .

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SecondProtection

BalancingTemp

Cellvoltages

Balancing

Microcontroller &Pheripherie

Powerboard

- Current Measurment- Power Switches

Level Shift

Seco

nd

Pro

tectio

n

Temperatures

Cur

ren

t

Shu

t do

wn

CAN

Battery Current

System OverviewSystem OverviewBattery Management

System

System Overview

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Discharge Charge

Load Discharge Charge Charger

Better for low current

Same connector for charge and discharge

Better for high current

Possible danger if not connected properly

Paralleling of MOSFET to reduce on-resistance

Power SwitchPower SwitchPower Switch

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Input:100—240V(AC)Output:29.4V 2A

Chargers

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Li-Polymer Battery Pack on our bike

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Li-Polymer Battery System for Cree Three-Wheeler

Our Future

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Drivetek ag Li-Ion Pack for the Antares Glider Plane from Lange Flugzeugbau

High Power Li-Poly BetteriesHigh Power Li-Poly BetteriesHigh Power Li-Poly Batteries

• Choose high quality battery• design a complete battery

pack.

• This includes:– Battery monitoring– Battery packaging– Thermal design– Charger Design– Fail Safe Behavior Design

• A battery information will also provide – Life cycle testing– Shock and vibration testing– Thermal cycle testing

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Cell RequirementsCell RequirementsOverview

Cell Requirements

• Nominal Energy: 9 to 12 kWhrs• Several Possible Nominal Voltages:

– 48V / 60V / 100V (13 / 16 / 27 cells)• Continuous discharge: 1C (continuous full speed)• Peak discharge: 2C for 1 minutes 50% duty cycle

– (stop n’ go acceleration)• Energy Density: > 130 Whr/kg at 1C• Lifetime: > 300 cycles at 70% DOD • Temperature range: automotive: -20°C to 50°C ambient

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Thank you very much for your attentionThank you very much for your attentionThank you very much for your attention

Anthony Lu

GUANGZHOU MARKYN BATTERY CO., LTD

Dr. Quansheng Yang

R&D Dept. Wuhan Factory 752,

ThanksThanksGood Bye

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