Why We Choose Li-ion Battery?
Li-ion Power Battery: The new generation power solution for Electric Vehicle-----a most advanced technology in the world ---the application tendency for lithium iron phosphate as cathode (Li-ion technology).
Due to the shortage of fossil fuels and environmental concerns, we re convinced that the green energy industry and related industries will become the main stream in the coming 30-50 years. This causes a strong demand of rechargeable batteries.
Lithium iron phosphate cell has the best safety characteristics, long cycle life (up to 2000 cycles) and good availability. It is very suitable for high discharge rate occasions such as EV (including e-bike, electric scooter, and electric car), power tools, UPS and solar energy system.
Key Features and Advantages of Li-ion media
High Performance
Extremely Safe/Stable Chemistry High intrinsic safety, no explosion & will not catch fire under collision, over charged or short circuit. High thermal stability of phases up to 500C.
High Rate Capability For all high power output application
Extraordinary Long Cycle Life Best can up to 2000 cycle life, would be over 8 times life of Lead Acid and 3 times of NIMH.
Environmentally Friendly Non-toxic, non-contaminating No rare metal, UL, CE, SGS/ROHS approved. Li-ion technology does not contain any heavy metals and does not exhibit the "memory effect" of Nickel-Cadmium and Nickel-metal Hydride solutions.
Another key benefit of our Li-ion technology is its flexibility, both in terms of battery application and cell design. Small in size and light in weight 1/3 weight of Lead Acid and 65% weight of NIMH.
PortaPower provides not only Li-ion battery pack, but also total solution which includes protect circuit module with balance charging function, BMS and specific charger.
COMPARISON CHART OF VARIOUS LITHIUM BASE BATTERIES
Li-ion LiCoO2
LiMn2O4
Li(NiCo)O2
SAFETY AND ENVIRONMENTAL CONCERN
Safest and most ENVIROFRIENDLY among all the listed groups - Excellent
Not stable - Very dangerous Acceptable Not stable - Very dangerous
CYCLE LIFE
Best among all the listed groups - Excellent
Acceptable Unacceptable Acceptable
POWER WEIGHT DENSITY
Acceptable
Good
Acceptable
Best
LONG TERM COST
Most economic - Excellent
High
Acceptable
High
ACCEPTABILITY
Excellent
(-20¡æ~ 70¡æ)
Decayed beyond 55¡æ ~ -20¡æ
Decayed extremely fast over 50¡æ
Decayed extremely fast over 55¡æ ~ -20¡æ
Chemistries Comparison
Cell Chemistries
LiCoO2
LiMn2O4
LiNiCoMnO2
Li-ion
Rate Voltage
3.7V
3.8V 3.6V 3.2V
Charging Voltage
4.2V
4.2V 4.2V
3.7V
Discharging end Voltage
3.0V
2.5V
2.5V
2.0V
Energy Density (Wh/L)
447
253
327
222
Energy Density (Wh/Kg)
140-145
105-115
140-155
120-135
Cycle Life
>300
>300
>1000
>1000
Self-Discharge Rate ( Month)
1%
5%
1%
0.05%
High Temperature Performance ( 55¡À2¡æ)
Good
Acceptable
Good
Excellent
Low Temperature Performance (-20¡À2¡æ)
Good
Good
Good
Good
High-rate Discharge (10C)
N/A
Good
Good
Excellent
Safety & Environmental Concerns
Bad
Good
Good
Excellent
Why do people choose to ride an electric bike?
Enjoy the feeling of riding a bicycle - except for hills, starts, and headwinds.
Prefer their local errands to be easy, hassle free and low cost.
Like to save money and protect the environment.
Look for extra chances to exercise - even if it's just a little. In fact, riding an e-bike can increase your fitness. You can ride to work without difficulty. You still have to exercise
Still need convenient, point-to-point transportation using safe traffic free bike lanes we have all paid for but rarely use!
Want their own traffic "lane", convenient parking spots and shortcuts. No traffic congestion
Considered a gas-powered moped or small motorcycle, but dislike the noise, smell, safety issues, starting problems and special laws.
Riding an electric bike doesn't mean you're lazy. You are a smart educated consumer reducing air pollution and having fun doing it.
Because you can be assisted when going uphill, you do not need to spend excessive energy, you feel less tired and your body continues to operate in your optimum aerobic zone.
Enjoy your ride and use the assist when you feel like it. They are not motor bike they require input from rider and motor to operate effectively.
With a conventional bicycle, many people exceed their aerobic zone when riding uphill then feel completely drained and are unable to enjoy the ride.
Can ride work in a suite or work clothes.
Can the bicycle and tricycles be ridden as "normally"?
Yes. The choice is yours - battery power and pedal power provide the best results and is they only way we recommend the use of the electric bicycle.
When should I recharge batteries?
We recommend you recharge battery after each usage or at least when 'battery status indicator' shows 'half flat' or less. This ensures you get the most power. Regular charging using a high quality switch mode battery charger will prolong the life of you batteries.
How long does it take to recharge the batteries?
Depends on state of exhaustion of battery. If battery totally flat - recharge time about 5-6 hrs. If half flat - about 2-3 hrs. Best to recharge overnight.
How far will the bicycle travel between recharges?
There are many variables that affect distance covered between recharges such as weight of rider, type of terrain, number of stop / starts, riding speed, amount of pedal assistance etc. Laboratory tests have indicated a maximum range of 65 km at 250 watt 36 volt 9 AH. Our experience shows that most riders get an average of 20 ¨C 50 km¡¯s. Correct tire inflation and pedal assistance will increase the distance you get from each charge. Electric Bicycles are required to be pedal assisted to ensure they achieve their specified ratings including rated power outputs. Remember cheap high power output motors often sold over the web are not only heavy and inefficient but use so much power they are not useful for commuting applications.
What maintenance is involved?
Basically there is no ongoing maintenance of electrical components other than recharging batteries. Many of our bicycles use the latest generation Brushless 6 Speed Hub Drive motors where there are no contact point inside the motor that can cause wear and tare. It is advised to keep bicycle clean at all times. Under normal use, motor doesn't need readjustment and maintenance except that its outer surface needs cleaning at regular intervals.
How e-bikes work?
Electric bikes are everyday bicycles with an added battery-powered electric motor. Although capable of pushing you along without your help, electric bikes perform noticeably better when you pedal. The average "couch potato" who normally rides at 10 mph can ride at 15-20 mph using the same effort. He can also expect a range of 10 miles, with a recharge time of several hours. Do you remember that easy pedaling after you get your bike up to speed? That's the cruising feeling you get all the time with an electric bike.
Power, when activated by a switch on the handlebar (power-on-demand) or in response to your pedaling, gives you an immediate, nearly silent push. When you release the switch (or stop pedaling), the motor coasts or "freewheels" - like when you stop pedaling a regular bike. Standard bicycle hand brakes and gearing round out the controls.
"Power-on-demand" means just that - no pedaling required! Although all electric (or "electric-assist") bikes are designed to work with your pedaling, power-on-demand allows you to break the rule. Most systems offer a variable speed control, although some are simply on/off (like the yellow switch pictured). It senses you are pedaling. And it's "power output to pedal pressure" ratio is often adjustable. Most people find 250-watt motors adequate for their needs, although folks with steep hills may want more power. Some bikes offer through-the-gearing power assist - i.e. the force of the motor goes through the bike's gearing system - which provides better hill-climbing and top-end speed than direct drive systems with the same size motor.
How e-bikes perform?
The most important factors are listed here with the (generally speaking) most important at the top:
terrain (number and incline of hills)
e-bike speed (range at 10 mph is 8 times as far as at 20 mph)
wind conditions (going 10 mph against a 10 mph headwind feels like 20 to the bike)
pulling a trailer (which is like pulling another bicycle)
correct tire inflation (under-inflated tires slow you down)
battery size (measured in volt-amp-hours)
weight of rider and baggage
motor/controller/drive system efficiency
As you can see, battery size and system efficiency rank near the bottom. The speed you go makes a big difference in how far you go.
All else being equal, range is a function of either 1) battery capacity (amp-hours X volts) or 2) speed and ease of recharging (high-power chargers provide lots of miles in less than one hour). There is a close relationship between battery capacity (A/hrs) and both weight and physical size (total volume). Generally speaking, the bigger the battery, the greater its capacity. For hill-climbing, expect about 3 feet of elevation gain for every volt-amp-hour.
All else being equal, speed is a function of motor (watt rating) and controller. Most scooter motors are capable of higher performance characteristics than the controller allows.
Is it legal to use electric bikes like ours on British roads?
In response to a question raised in Parliament September in 2003, Transport Minister George
Jamieson MP stated on September 15, 2004:
"Electrically assisted pedal cycles complying with the requirements in The Electrically Assisted Pedal Cycles Construction and Use Regulations 1983 are able to use facilities provided for ordinary bicycles. The Government are committed to encouraging more cycling as a healthy, useful and enjoyabl means of travel."
In summary, under the regulations referred to above, an electric bicycle is not considered a motor vehicle and therefore does not require a licence, third-party insurance, road tax,registration plates if:
The bicycle weighs less than 40kg without its rider.
The Agattu weighs around 25kg with battery.
It cannot exceed 25kph - about 15.5mph - under power.
The Agattu's top assisted speed is about 15.5mph. The motor helps you get up to speed from a standing start and stay there - you can use the pedals to exceed 20mph.
It has usable pedals
Many electric bikes and scooters come with basic pedals just to keep within the rules and are too heavy to ride. Ours are fully-functioning road bikes with electric motor assistance.
Its motor has a rated output of less than 0.25kW (i.e.250 Watts).
The Agattu's motor is a 'strikingly efficient' 250W model.
All our electric bicycles comply with these rules and with the new EN 15194 standard that will come into force across the European Union shortly. You will not need to register your bicycle, hold a licence, take out compulsory insurance or pay road tax. However, you must be aged 14 years or over