There are two core parts on the electric bicycle , the motor and the battery . Battery is one of the most vital component of an electric bike. As an old hand or the green hand e-bike user, you should known the importance of the electric bike battery. So , How to choose the right battery for electric bike? How do we know which one is the best of various ebike battery types?  What type of battery cells should I choose for my electric bike?

 

In this article , we talk about the choice of the ebike battery . we will deal with many questions that confuse you . This article also contains information about the differences between types of batteries . In addition, we will let you know some factors that you should keep an eye on before choosing an electric bike battery for your ebike. Come on ,follow me to learn how to choose the best e-bike battery .

 

Before choosing the best battery for your e-bike, you have to understand the terminology used to describe electric bike batteries , that will make you quickly understand about batteries.

 

Common terms used on battery or motors

Voltage (V)

Amperes (A)

Ampere per hour (Ah)

Watt per hour (Wh)

Watts (W)

Torque (N.m)

 

Voltage (V)

This is known as volts, Common voltage we used on electric bike is 36v / 48v / 60v / 72v . Battery cells can withstand a range of voltages , such as , when a 48v battery fresh off the charger , it would be about 54.4V . Different battery voltage are used to adapt different motor power.

For example :

Battery voltage :	36V	48V	60V	72V
Motor power :	250W	500W	1000W	2000W
	350W	750W	1500W	3000W
	500W	1000W	2000W	5000W
	750W	1500W	3000W	8000W
		2000W

Learn more : How to choose the motor for you ebike ?  Front/rear hub? Hub/mid ? 250w/8000w?

 

Amperes (A)

It's a international standard unit , used as the unit of electrical current . You can simply think it as the diameter of a tube , the bigger the diameter is ,the more the water can get through within the same time.

 

Ampere per hour (Ah)

This is a unit of the battery's capacity , for example : A battery of 13Ah ,means this electric bike battery can diacharge 1.3A for 10 hours, or discharge 13A for 1 hour .

 

Watt per hour (Wh)

“Wh” is a another unit of the battery's capacity , for example : A battery of 680Wh , means this e-bike battery can discharge 68 watts for 10 hours , or discharge 680 watts for 1 hour .

 

Watts (W)

This is a standard unit of motor power , higher watts make your e-bike more powerful . Watts = Voltage * Amperes , the more power you need , the more voltage and amperes you need , but not the higher current the better , Heat = Ampere^2 * resistance * time , high current will cause overheating of wires and other equipment , that will not only reduce you electric bike performance , but also waste your electric bike battery's energy . Some one may say “Can i use a 1000v battwey with 1 ampere ? that looks good !” NO NO NO , on the other hand , we should know that higher voltage will easier break down the insulating materials . By the way , we can use the “3KW” to represent “3000W”.

 

Electric bike battery types

There are many types of battery ,such as Nickel-cadmium Batteries /Nickel-Hydride Batteries /Lithium-ion Batteries /Lead Acid Batteries and so on . In this article ,we just talk about 2 types that can be used on electric bike nowadays : lead acid battery and lithium-ion battery .

 

Lead Acid Battery

As we all known , this type batteries are cheap , heavy , stable . They have less capacity if compared with other battery types of the same weight and size. Lead-acid batteries have some main uses : backup power , deep-cycle , starts system in cars , they can also be used for electric bikes , but they are a litttttttle heavy . Its's almost the heaviest battery of all the types , three times heavier than lithium battery ,two times heavier than nickel battery . The maximum capacity of a lead acid battery is half about the lithium battery .

 

Lithium-ion Battery ( 18650 Cell )

There are about 90% of electric bike battery on the market is lithium battery , lithium battery is becoming the default battery for the e-bike . Lithium batteries can produce more power compared with other battery at the same weight , more importantly , they will last longer . But , you still need to know how to maintain them .

Though lithium batteries are more expensive , we recommend using the lithium batteries for your e-bike , they are the ideal type for every electric bike , in range ,weight , cycle life ,and more . So , for good riding experience , we suggest the lithium battery .

Learn more : how to mantain your electric bike battery.

 

 

Things should take care of

Watts

First you should known how much motor power you need and does it legal in your region . According to electric bicycle law , when in US , the motor power must less than 750 watts , the speed must less than 36km/h ( 20 mph ) ; when in Europe , the motor power must less than 250 watts , the speed must below 25km/h ( 15.5 mph ) . Though we can provide motor power from 250W to 8KW , you should ride your e-bike legally in your region , check the laws in your region first . The higher motor power means higher torque , higher torque can give more boost power going up hill or starting . Also ,higher power can give you a faster top speed ( Top speed can be limited ). Usually , when at the same motor power , the gear hub motor have a higher torque compared with the direct-drive( gearless ) hub motor .

learn more : What is the difference between gear hub motor and direct-drive(gearless) hub motor

 

Voltage

Every electric bike has it's voltage range , it depends on motor and controller and something else . Our Saili Motor brand electric bike and e-bike kits input voltage could be set by the controller , like 36V 48V 60V 72V , according to the battery's voltage . Higher voltage means you can reach the same motor power with lower current compared with the lower voltage ; lower current makes lower heat produced and energy waste by wires and other equipment , make the whole e-bike system more energy efficient .

The nominal voltages used for e-bike is 36V 48V 60V , sometimes 24V or 72V , generally , all electric bicycle batteries comes with the 18650 lithium-ion battery cells , per cell's voltage is 3.7V ( 4.2V when fully charged )

Learn more : Why e-bike battery comes with 18650 cells

 

Amperes

Higher amperes bring higher power and torque , also ,the higher heat by wires , you can not have it both ways . The highest current the battery can provide depends on the quality of cells and the battery's BMS , so you should choose the high quality battery cells and BMS , don't just look at the cheap price , you get what you pay for .

 

To sum it all

1,Choose the high quality 18650 battery cells with BMS.

2,Choose the suitable voltage according to your motor power.

3,Bigger capacity gives you more miles.

Learn more : How far can i go ?