Can I Make My E-bike Go Faster by Using a Higher Volt Battery?

We are getting questions about if we can increase our hub motor efficiency by using higher Voltage. Or If we use 60V, 72V or higher volt batteries in our 36V or 48V motor, can we go faster? The answer is sometimes yes but with a lot of cost and risks. Lets talk about this a little more and I will try and keep things as simple as possible…

There are e-bikes out there that offer batteries such as 60V or even 96V. So what are the risks attached to these? First, it could be a poor-quality battery that will burn out quicker, or it could have protocol communication problems between the motor and the controller. But for this Q&A let’s assume they are packed in a good way without any defects and the battery is in perfect condition and of a good quality brand.

The motor which is used in your e-bike is wired to handle a certain voltage and if you increase the voltage, especially in huge amounts such as 60V or 72V it will create more current. In this way, you can have a faster e-bike by simply swapping your battery for a higher voltage one. But…

Electric Bike Hub Motor

OK, so for a while adding more current will result in you getting more torque. But more current also means more heat. The result will be an overheated motor and in a short time you will most probably end up with a burned motor which is out of warranty. No e-bike or bike company will take responsibility for damage caused in this way.

So let’s handle the subject in a little bit more technical way…

Every motor is basically a generator, they create EMF (Electric and magnetic fields) and voltage. The created back EMF will match the voltage motor receives. If you supply a higher voltage then the motor can’t match the EMF to the input voltage. This will break the perfect balance and it will destroy your motor in no time at all.

If you supply too much voltage, the load will keep the motor reaching a certain speed and in this way, the motor will try to suck more current from the battery. At this time the extra sucked current will start to heat the wires and the motor. Also, it can let certain safety sensors burn out as well.

There are better ways to have a faster e-bike such as buying one that suits your needs. Use a powerful Hub motor with a very sophisticated gearing system that can create very high torques. For example a 250W mid-drive model can create much higher torques compared to 90% of 500W real-wheel hub e-bikes. Also a good BMS (Battery management system) system can give you even more current to the motor when need it (but you can always control it).

To be honest with you most people are never going to need their e-bikes to go more than the UK law permits which is 15.5 MPH and trust me, that is more than fast enough while out riding on a bumpy path. In most people’s cases it is more torque they want, not more speed. But either way, I hope this has answered your questions…