This is a common question many ask when they encounter 52v batteries while looking at a 48v ebike conversion motor kit. Can you safely use a 52v battery on a 48v motor? The answer is yes, almost always. Let's take a look at why choosing a 52v battery is a good thing and not a cause for concern.
The advantages of 52v batteries:
- 52v batteries are faster. Increased voltage means increased motor RPM, and your motor will spin more quickly as the voltage increases. If you need a little extra speed or power, you’ve got it.
- 52v batteries are more powerful. Higher volts translate to higher watts, increasing your power for climbing hills and riding into headwinds.
- You get more range if you're not using that extra power for speed. You simply go further before requiring a recharge, and 52v is your best option for a more extended range on one charge.
The advantages of 48v batteries:
- It’s a few ounces lighter and not enough to matter. They are both typically the same size.
- Cheaper. Sometimes a little, but usually not at all.
- It’s necessary for some controllers and motors. However, most of the 48v controllers and motors available today can also use 52v batteries.
They both look the same but one has 4 more cells and that much more capacity and power.
Takeaway: It's simple; you get more power and range with a 52v battery than with a 48V battery. With more power for climbing hills, accelerating faster, and more capacity for going farther, 52v batteries have the advantage.
When is a 48v battery required?
Some motors and controllers are indeed rated as 48v, making some people nervous about putting a higher voltage battery on them. Occasionally this concern is valid, and as mentioned above, the motor or controller only works with a 48v battery. However, if the company you are buying it from sells a 52v battery with a 48v motor, that means they know it works, and in our experience, it probably works better.
52v batteries and Electrify Bike Company
We have sold thousands of 52v batteries on 48v motors and have had better results than with 48v batteries. Hence we sell 52v batteries 10 to 1 over 48v batteries. Here is a sampling of the 52v batteries we sell. When paired with a 52v battery, all the motors we sell have all the above advantages.
52v batteries have performance benefits over 48v batteries, and the increased capacity and power allow you to go longer distances faster.
The preceding discussion is the simple version of why 52v batteries are a good choice. If you would like to dive a little deeper (but not a lot), keep reading. Does that mean 48v batteries and other batteries are a bad choice? No. The truth is a lot more complicated, and there are reasons engineers design electric bikes with 36v, 48v, 52v, 60v, and 72v batteries. So, if 52v batteries are better than 48v batteries, does it follow that 60v batteries are better than 52v? Once again, no, and the reason is more complicated. 52v batteries hit the sweet spot on several fronts. It turns out that most 48v and 52v controllers have electronic components that max out between 60v and 64v. Higher voltages will burn them out. That is why it is safe for 48v controllers to tolerate voltages up to 60v. 52v batteries have a maximum voltage with a full charge of 58.8v, so this is a safe voltage for the components in a 48v controller. Motors are even more tolerant. They just spin faster, given higher voltages. On the other hand, a 60v battery charges up to 67.2v, which would burn out many of the critical components in a 48v or 52v controller.
As the voltage rises past 60v, there is another safety-related issue for tinkerers and DIYers. The likelihood of an electric shock stopping your heart if you accidentally get shocked is considerably higher at 60v and above.
If 48v is slower than 52v, wouldn’t 36v be super slow? A motor designed to run with 36v will not be slower. Engineers have another way to determine the speed of the motor. The number of windings in the stator sets the rpm of the motor at a given voltage. Fewer windings in the motor stator cause the motor to spin faster, while more windings spin slower. A 36v motor and a 48v motor can have the same speed by adjusting the number of windings. However, if you apply 48v to the 36v motor, it will spin much faster but have less torque. Some DIYers do this deliberately to get a faster ebike, but you must know what you are doing because it is possible for the motor to overheat because of the amps required to get the torque necessary to move the bike.
So to circle back to 52v vs. 48v batteries, should we be leery of getting a 48v system to spin faster? Remember that we said 52v was in the sweet spot? It is only a few volts higher than 48v batteries and is within the safe zone for motor and controller components. You can use the extra cells in a 52v pack for a bump in power and speed, or if you take it easy, those extra cells will simply give you more range.
When someone wants a second battery on a 48v ebike, we often recommend a 52v battery tied together with a dual battery module to the original 48v battery. It works well because there is a considerable voltage overlap between 52v and 48v batteries. 52v batteries range from a full 58.8v down to an empty 42v. In comparison, 48v batteries run from a full 54.6v down to an empty 41v. So the voltage overlap between them is from 54.6v on the high end to 42v on the low end. The dual battery module will use the 52v battery from its full charge at 58.8v down to 54.6v. At that time, it will tie both batteries together, providing the total amps of both batteries to the motor while the two batteries go from 54.6v down to 42v when they are empty. This process also happens when two 48v or two 52v batteries are tied together with a dual battery module, and the two batteries have different charge levels.