E bike battery overview: how to choose?
Updated: Feb 9
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The battery is an important part of the electric bike, which autonomously supplies the electric motor with electricity. The e bike battery determines its weight, cycle life and operating temperature range. The mileage of the e-bike on a single charge depends on the battery capacity, the voltage of which affects the speed and must match the operating voltage of the motor and controller. Therefore, the battery for an electric bike must be selected taking into account the desired range and the characteristics of other electrical components.
Electric bicycles are equipped with the following battery types:
Lithium iron phosphate (also called Lifer)
Lithium Ion (Lithium)
Lithium Polymer (LiPo)
Beginners, as well as people who are morbidly cash-strapped or trying to save money most commonly use AGM lead-acid batteries. Some cyclists go even further and make batteries from uninterruptible power supply elements, which are the cheapest. The main problem with these elements is that they are designed for surface currents and do not live very long in the mode of deep discharge - charges. Factory AGM type battery packs work better and last longer as they are designed to be used as electric vehicle traction. When purchasing, you only need to test the battery to make sure it works.
Now let's take a closer look at each battery type.
Lead acid e bike battery
Lead-acid batteries are cheaper than others, they are unpretentious in operation and can work in cold weather. These batteries are:
safe to use
heavier than others
therefore load the e-bike
affect handling and reduce load capacity.
If we use batteries with a small capacity and light weight, less than those recommended by the manufacturer for a certain type of wheel e-bike motor, then their capacity will decrease at a high discharge current. If you ride your electric bike with a small battery, it is recommended:
don't accelerate hard
don't accelerate quickly
Avoid high speeds.
When completely discharged, the e-bike battery quickly loses its capacity and ability to recover. The installation of low-power lead-acid batteries does not help either in terms of top speed and mileage or in terms of durability. Only save on weight, but you need to change batteries 2-3 times more often than normal capacity. So if you take "Lead", then only the capacity that is recommended.
Rahul, co-founder of GIN X e-bikes, says nobody uses lead-acid e-bike batteries these days because they are outdated and heavier for electric bikes.
Lithium polymer batteries for e-bikes
E-bike lithium polymer battery packs are cheaper than others, have high output current and light weight. Incidentally, such batteries are installed in all mobile electronics - from mobile phones to laptops. They usually serve 4-5 years reliably. If you treat it with special care, then even more so. The main disadvantage of these batteries is their poor fire resistance. If mechanically damaged or overcharged, they can ignite. Therefore, to avoid the first risk and avoid the second, use a regular charger that all regular companies sell complete with a battery. LiPo batteries too:
don't like frost, in the sense that they work, but their capacity is reduced;
It is impossible to charge them in the cold;
to increase safety, it is recommended to protect this type of battery with fireproof cloths, bags and cases when self-assembling and it is advisable to be vigilant at all times.
Battery cells do not require careful balancing like other battery types.
Lithium-ion batteries for e-bikes
Lithium-ion batteries are safer than LiPO, they are slightly more freeze-proof, weigh more and cost more (price fork between LiPo and LiFePO4 batteries). The most common type of these batteries is lithium manganese. Lithium-ion batteries also include lithium-iron-phosphate batteries (LiFePO4), which are characterized by this:
high power density;
ability to work in cold weather;
large number of charge/discharge cycles.
Although it costs more and in relation to the total amount of energy delivered over the entire operating time, the energy obtained from lithium iron phosphate e-bike batteries will not be cheaper than the energy from lithium polymer batteries.
Rahul, CEO of GIN X E-Bike, mentions that lithium-ion e-bike batteries are very efficient and widely used e-bike batteries. This is the main reason why, when developing the GIN X electric bike, he preferred the Tesla-grade 48V lithium-ion battery for improved performance.
Also read our article about Fastest Electric Bike: Review of 2022
Overview of the voltage of the E Bike battery
So we are familiar with ebike battery types, we understand a bit in terms, now it's time for me to tell you the most important thing - the battery voltage. There are few types of ebike battery voltages:
We sell batteries with a voltage of 48 volts. 36 and 48V e-bike battery accounts for 90% of the e-bike battery market. On request we can make a battery for 52V e-bike batteries, 60, 72 and higher volts, but this is possible on a separate request.
Most e-bikes that you know are above 12V, and their voltage starts to rise from 24V, and they are very weak. As you know, small 36V bikes are the average standard in this evolution of e-bikes.
And completes this chain of e-bike battery 48-volt systems that are usually installed on high-power bikes. By the way, our GIN X e-bike has a 48V battery. Of course there are craftsmen who attach 60 and 72 and 96V electric systems to the bike, but most electric bikes work in the 36 and 48V e-bike battery range.
This legacy dates back to the days when acid batteries were used in everyday life, including in electric bikes. And if you look inside the acid battery, they are made up of 2 volt cells that can be easily connected in groups of 6 to make a 12 volt battery. And already based on this result you can make 36 and 48V e-bike batteries. In general, this voltage has become common on electric bikes.
The top speed of an electric bike depends on the voltage. For example, when the Bafang BPM motor is idling on a stand with a voltage of 36V, the top speed is about 37 km/h, and when it is at 48V, then about 45 km/h.