The electric bike battery is one of the most important parts of the electric bike because without it the electric bike becomes a normal bike
On the other hand, the battery is considered one of the most expensive parts of the electric bike, as its price reaches $1,000 in some models, and the price ranges between $500 and $600 on average.
So, the question is, can the electric bike battery be repaired? is a logical question considering the price of the battery and its importance to us as electric bike riders.
In this post, we will explain the five most important battery problems and ways to solve them.
Warning: Any steps explained in this post will be tested at your own risk. If your information is limited in electricity, we strongly recommend going to the nearest professional technician to help you.
Can Ebike Batteries Be Repaired?
As a general rule, electric bicycle batteries can be repaired, as the main components of the battery are the battery cells, BMS board, wires, and all the previous parts can be easily changed, and based on this, you can repair the battery by changing these parts.
Now let’s start showing the most important problems that may occur in the battery, their symptoms, and how to solve them.
1-BMS board Problems.
The battery management system or BMS is the system responsible for protecting the battery cells by passing or cutting off electrical current to the cells.
In order to understand how it works in a practical way, the BMS board is connected to all the cells in the battery and measures the charge for them and when the first cell is discharged, the BMS shuts down the battery completely to save it from any potential damage.
From the way the BMS works, it becomes clear that the idea of charging or discharging is controlled by the BMS.
Therefore, if you find your battery has some charging, but it is not capable of charging or discharging, this is evidence that a problem occurred in the BMS.
How to solve the BMS Problems.
In general, there are two ways to solve the problems of the BMS, which is to do a reset or to replace it (personally, I prefer the replacement, as the price of the BMS is not expensive)
To do a BMS reset you can do the following steps:
- Remove the outer cover of the battery.
- Disconnect the BMS cable connected to the cells.
- Connect the battery to the charger and start charging.
- While charging, connect the BMS cable
by doing the above steps the BMS will be reset to the default setting
You can also see this post, which explains other ways to make a BMS rest with pictures.
Replacing the BMS Board.
There are three main cables that are connected to the BMS
(P-) which is the cable responsible for the negative discharge to the connector.
(C-) which is the cable responsible for the negative charging to the connector.
(B-) which is the cable responsible for the negative connection to the battery
- soldering iron
Steps for replacing BMS Board.
- Remove the outer cover of the battery.
- Dismantling the BMS solder for the three main cables.
- disconnect the connector connected to the cells.
- Install the new BMS in the same place.
- Resolder the main cables.
- Connect the connector connected to the battery cells.
- Test charging the battery.
- If all went well put back the battery cover.
Important note: In most cases, BMS damage is a result of a damaged cell inside the battery. Therefore, it is preferable to measure the voltage of all cells before placing the battery cover again to ensure that all cells are working efficiently.
2-One or more cell damage.
The second most common cause of damage to an electric bike battery is a damaged cell or group of cells inside the battery.
In this case, you will not be able to operate the battery at all.
You can determine the damaged cell by measuring the voltage of each cell separately and you will find that most cells have constant readings (such as 4.1 or 3.8)
When you find a cell that reads too little, that cell is the problem.
There is also evidence of battery damage that can be observed with the naked eye, which is that you will notice the presence of black matter and cuts in the cell cover.
Note: Changing the cells requires specialized devices to ensure that the battery works properly, so it is preferable that it be carried out by a professional person.
And do not worry, the cost will be very low because you have done all the work and identified the defect, and all you want is to connect the new battery. You will not pay much!
The last main reason for battery malfunctions is the presence of a cut or disconnection in the internal wires of the battery, whether this cut is in the main wires of the battery or in the wires connected to the cells, this battery stop working.
Generally, this problem occurs as a result of the battery falling and hitting the ground. If you maintain the battery of your electric bike, you are safe.
In order to solve this problem, all you have to do is remove the outer cover of the battery, then locate the cut wire and reconnect it.
Then using a voltmeter, to measure the voltage of the battery. If you find the voltage reading is equal to the same battery capacity, you can find out the battery capacity through this equation (number of battery cells * 4.2)
Connect the battery to a charging source to make sure that charging is working, then cover the battery cover.
4-Battery pines are damaged.
When the battery is connected to the electric bike, it may cause damage or breakage to the battery pins, which will cause the battery to stop working.
You can tell that the problem is in the PINS by checking it with the naked eye and also in most cases the battery will not fit on the bike correctly.
To solve this problem, you can try to modify the PINS using a screwdriver, but you must make sure that the battery is turned off first.
Second, you can completely change the part that comes out of the battery.
5-Charger may damage.
It is possible that your inability to use the battery is due to damage to the charger and not a problem with the battery itself. To know that the problem is not in the battery, charge it with another charger or do a test for the charger.
You can see this post, which explains in detail how to test the electric bike battery charger.
As a general rule, the electric bike battery can be repaired by changing the internal cells, BMS board, or changing internal wires.
One of the most important problems that occur in the electric bike battery is damage to the BMS, damage to the internal cells or a cut in the internal connection wires, and finally, the battery pins can be damaged as a result of removing the battery incorrectly.