Transcript History of Lithium Polymer Battery Packs for EV

GM BATTERIES
Presentation
Li-Polymer Battery Packs for E-bikes
Anthony Lu
GUANGZHOU MARKYN BATTERY CO., LTD
Dr. Quansheng Yang
R&D Dept. Wuhan Factory 752,
1
Safety Test
DROP
Needle stabbed
Impact
2
Main Characteristics
Of Lithium polymer Battery Packs
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
–
–
3
Temperature Characteristics for E-bikes
Of 24V/12Ah Lithium polymer Battery Packs
Charge:CC/CV 2A,29.4V×8h,25℃
Discharge:6A cut off at 21V
30
℃
Voltage\v
29
℃
25
℃
℃
℃
21
20
Discharge time/min
4
Discharge Characteristics for E-bikes
Of 24V/12Ah Lithium polymer Battery Packs
Charge:CC/CV 2A,29.4V×8h 25℃
Discharge: Cut off at 21V
30
29
25
21
20
Capacity rate%
5
Cycle life Characteristics for E-bikes
Of 24V/12Ah Lithium polymer Battery Packs
Capacity ration(%)
Charge:CC/CV,29.4V(1CA)×3.5hrs,25℃
Discharge:Constant current 1CA,25℃
Number of cycles
6
History of Lithium Polymer Battery Packs for EV
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.
7
History
History of
of Lithium
Lithium Polymer
Polymer Battery
Battery Packs
Packs for
for EV
EV
Battery packs for E-bikes is an important development project and developing direction, experienced 3year research and test in actual application.
8
History 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 feedbacks on typical problems:
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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)
10
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
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The evolving 24V10Ah for e-bike
Mail Characteristics of Li-ion Polymer battery Pack
Nominal Energy: 240 Whrs
Nominal Voltages:24V (7 cells)
Continuous discharge: 1C (continuous full speed)
Peak discharge: 3C for 1 minutes
Energy Density: > 130 Whr/kg at 1C
Lifetime: > 300 cycles at 70% DOD
Temperature range: -20°C to 50°C ambient
Dimension:42*120*270(mm)
12
Temperature Characteristics for E-bikes
Of 24V/12Ah Lithium polymer Battery Packs
Charge:CC/CV 2A,29.4V×8h,25℃
Discharge:6A cut off at 21V
30
℃
Voltage\v
29
℃
25
℃
℃
℃
21
20
Discharge time/min
13
Charge Characteristics for E-bikes
Of 24V/12Ah Lithium polymer Battery Packs
Charge:2A,29.4V×8h,25℃
30
Current/A
29
Charge current
25
Voltage/V
Charge voltage
21
20
Charge time/h
14
Discharge Characteristics for E-bikes
Of 24V/12Ah Lithium polymer Battery Packs
Charge:CC/CV 2A,29.4V×8h 25℃
Discharge: Cut off at 21V
30
29
25
21
20
Capacity rate%
15
Cycle life Characteristics for E-bikes
Of 24V/12Ah Lithium polymer Battery Packs
Capacity ration(%)
Charge:CC/CV,29.4V(1CA)×3.5hrs,25℃
Discharge:Constant current 1CA,25℃
Number of cycles
16
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
.
17
System Overview
Battery Management System
Level Shift
Cellvoltages
Second
Protection
Temperatures
CAN
Balancing
Balancing
Shut down
Second Protection
Current
Temp
Microcontroller &
Pheripherie
Powerboard
- Current Measurment
- Power Switches
Battery Current
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Power Switch
Discharge
Charge
Charger
Charge
Discharge
Load
Better for low current
Better for high current
Same connector for charge
and discharge
Possible danger if not connected properly
Paralleling of MOSFET to reduce on-resistance
19
Chargers
Input:100—240V(AC)
Output:29.4V 2A
20
Li-Polymer Battery Pack on our bike
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Our Future
Li-Polymer Battery System for
Cree Three-Wheeler
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High Power Li-Poly Batteries
Betteries
• 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
Drivetek ag Li-Ion Pack for the Antares Glider Plane
from Lange Flugzeugbau
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Cell Requirements
Overview
•
•
•
•
•
•
•
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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Thanks
Good Bye
Thank you very much for your attention
Anthony Lu
GUANGZHOU MARKYN BATTERY CO., LTD
Dr. Quansheng Yang
R&D Dept. Wuhan Factory 752,
25