

The battery pack is the heart of any electric vehicle. There are two major types of batteries: Lithium-ion and Lead Acid. As the name suggests, lithium-ion battery packs use lithium as the primary compound at the positive electrode while the negative electrode is usually made out of graphite. These batteries have a higher charge density, low self-discharge levels, and are generally lighter than lead acid batteries. They also offer better range and faster charging capabilities, but come at a higher cost. The Ather 450X is a perfect example of an electric two-wheeler powered by a lithium-ion battery pack. The first rechargeable batteries to have ever been created are in fact lead acid batteries. Modern electric vehicles use Valve Regulated Lead Acid batteries (VRLA), wherein the lead electrodes are suspended in a gel-like electrolyte. These batteries are less expensive to make but their charge density isn’t as good as lithium-ion ones, so the range offered is relatively lesser. They are also heavier and take longer to charge. A prime example of an electric scooter powered by a VRLA battery is the Hero Electric Optima LX.
The energy stored in the battery is translated into motion using an electric motor. There are two major types of electric motors: Hub and Frame-mounted. The brushless DC hub motors, in particular, are used in most of the electric two-wheelers. They are fairly easy to install, do not require transmission components, and are affordable to manufacture as well. However, they result in an increased unsprung weight, which negatively impacts the handling of a two-wheeler. The TVS iQube Electric is a great example for an electric scooter with a hub motor. Frame-mounted motors, or mid-drive motors, are mounted onto the vehicle’s frame, and are linked to a transmission drive, which is usually either a belt or sometimes a chain. These motors are powerful, and also ensure the centre of gravity is optimised in a two-wheeler. But on the flip side, they are expensive, and the transmission drives may need regular maintenance. The Ather 450X comes with a frame mounted motor.
Electric two-wheelers have either a fixed battery pack or a removable one. The chassis of EVs with fixed battery packs are relatively simple, and are easy to manufacture. But since they cannot be removed, the electric two-wheelers will have to be heavily dependent on charging infrastructure. The Bajaj Chetak electric scooter comes with a fixed battery pack. Two-wheelers with removable battery packs have their chassis designed in a way to accommodate easy installation and removal of the batteries. This increases the engineering complexity, and thereby ends up increasing the manufacturing costs. But the biggest advantage is the ability to simply remove the battery pack and charge it wherever convenient. The Revolt RV 400 comes with a removable battery pack, which can easily be replaced with a fresh one in minutes.
There are two ways to charge a battery pack. The conventional way is to simply plug the charger into a 3-pin 5A socket and let it charge overnight. While this takes a long time to charge the battery completely, it does not heat up the battery pack as the amount of current induced is low. The Hero Electric Photon HX, for example, takes 5 hours to charge completely. On the other hand, a fast-charging system sends large amounts of current into the battery pack, thus charging them up quickly. However, batteries that are compatible with fast charging systems need to have excellent thermal management to ensure their longevity. Electric bikes and scooters with fast-charging technology are expensive too. The Ather 450X uses a proprietary AC and DC combined fast-charging system that can juice up the battery in over an hour.
How much money does one need to spend on charging and running an Electric bike? Does an electric bike cost less or more than petrol bike on a daily basis? The running cost of EV bikes can be compared with that of petrol bikes using our calculator. Choose your favourite models to compare and see the cost per km incurred on your EV and petrol bikes.