How To Reset Electric Bike Battery?
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How To Reset Electric Bike Battery?

Views: 634     Author: Site Editor     Publish Time: 2023-01-31      Origin: Site

How To Reset Electric Bike Battery?

The battery is one of the very important parts of an electric bike, not only because it is the second most expensive part after the motor, but also because without it the bike would not be an electric bike.

Since the battery, as we mentioned, is one of the most expensive parts, replacing it will be expensive, so knowing a little about maintaining your battery may save you a lot of money.

The good thing here is that the internal contents of the battery are not complicated at all. In this article, we will learn how to reset electric bike battery with BMS.

1. What Is The Function Of The BMS On Your Ebike?

Lithium-Ion batteries include a microprocessor that controls charging, overcharges, and discharge. These monitors are called BMS (Battery Management System). The function of the BMS is to protect the battery and make sure that all the battery cells are balanced, and in the event of any problem, it disconnects the connection immediately

In order to do a BMS test, you should first know what you are going to test?

What we will test are the main connections of the BMS with the battery cell groups because BMS has two types of connections.

The first type: is the connection of the BMS with the battery cell groups & the cells themselves.

The second type is the connection to the motor through the controller, as the motor does not communicate directly with the battery cells, but is via the BMS chip.

Below is our Merrygold ebike with BMS:

How To Reset Electric Bike Battery

How To Reset Electric Bike Battery-2

A BMS reset could solve the problems you're having with your battery. So, to learn how to reset battery and save money.

2. How To Do A BMS Reset For An Ebike Battery

As mentioned before, there are generally two ways to reset the BMS: to do it externally or internally. You could choose to try whichever one you feel most comfortable with. However, if it doesn't work, you may need to try the other approach as well.

Still, let's take a closer look at both approaches.

Reset The BMS Externally

The first method for resetting your e-bike battery's BMS is to do it externally. By that, we mean performing a reset without opening the battery compartment and accessing the BMS directly. To do that, you’ll be using a makeshift adapter to charge the battery through the discharge port, which should cause the BMS to reset itself.

Here's how to make that adapter.

Step One: Create the Adapter

First of all, you should put on your safety gloves. You'll be working with a soldering kit and later with live electricity, so you'll want to keep yourself protected at all times.

Your adapter will consist of the DC barrel jack and two wires. Using the soldering kit, attach a red wire to the positive terminal of the jack and a black wire to the negative one.

You could also use electrical tape to keep it all together and cover any bare parts.

Step Two: Test the Adapter

Here, you'll be plugging one end of the adapter into the battery charger. With your multimeter, check that the adapter is conducting electricity. Remember: red wire to positive, black wire to negative.

You must never let the bare wires touch each other, as that could close the circuit and make things very dangerous.

Step Three: Perform The BMS Reset

Next, connect the adapter to the battery's discharge port. Look closely at the port, and you'll see that it has indicators to show you where to plug each wire. It's usually printed on the plastic itself. The red wire goes to the positive terminal, and the black wire goes to the negative one.

If it's working, you'll see that the light on the charger turns red. Hold the wires just as they are for 15 seconds, and that should cause the BMS to reset itself.

Once that's done, turn off the battery charger and remove the adapter. You can now check to see if the BMS allows the battery to charge and discharge as normal. You can do this by replacing the battery back in the e-bike or connecting it to the charger.

Reset The BMS Internally

As you can see, resetting the BMS external involves working with live electricity, some custom wiring, and a DC adapter. If you feel unsure or uncomfortable with working that way, don't worry! That's totally normal. Many people would prefer using this second method instead, as it's much more straightforward.

Here's how you can go about resetting the BMS internally.

Step One: Open The Battery

Firstly, you'll need to use your screwdrivers to open the battery's top cap. Typically, there are a few screws that keep the top cap in place.

Doing that will give you access to the inside of the battery, where you will find the BMS, battery cells, and the wires that connect everything together.

Step Two: Pull The BMS Chip Out Slightly

The BMS and battery cells are kept safe deep inside the battery case. So, to make it easier to work on, you'll want to gently slide everything out by just a little bit. You don't have to remove everything entirely; the goal here is to have the BMS out in the open so you can inspect it closely.

Remember: Don't pull forcefully on any of the wires or cells that you see. A gentle nudge is often all that's necessary.

Step Three: Reset the BMS

Take a closer look, and you'll see that the BMS has several wires connecting to it in the form of a harness. Here's what you'll need to do next:

Disconnect that wire harness.

With the wire harness disconnected, plug the charger into the battery. Your charger should be on.

Lastly, reconnect the wire harness to the BMS and seal all of the parts back in the battery case just the same way as before.

Then, test the battery to see if it's working correctly again. Remember to check that the battery can both charge and discharge. Test its charging ability by plugging it into the charger, and test its ability to discharge by putting it back in the e-bike.

The BMS prevents overheating and helps lengthen the battery's lifespan. That is why we could reset ebike battery when it has trouble.

3. Why Would You Need To Perform A BMS Reset?

So, why would anyone need to perform a BMS reset? Well, if you're reading this article, you're probably here for one of two reasons.

Firstly, it could be that your battery isn't working. To be exact, your e-bike battery isn't charging or discharging as it usually does. In such a case, a BMS reset could be exactly what you needed.

The second possibility is that you've been troubleshooting a battery problem with the manufacturer's Customer Service or a fellow e-bike enthusiast, and they've told you to try resetting the BMS.

In either case, they're probably right. Performing a BMS reset could solve whatever battery problems you're facing. Plus, it's an excellent first step to troubleshoot the issue and potentially avoid buying an expensive replacement unit.

4. Conclusion

At this point, it's safe to say that learning how to do a BMS reset is an essential skill for any e-bike owner. Having that ability would save you plenty of effort (and money) if you were to ever experience a battery that refuses to charge or discharge correctly.