How to Reset E-bike Battery? [ A Simple Guide]
The battery is a highly significant component of an electric bike, not only because it is the second most expensive component after the engine but also because the bike would not be an electric bike without it. Because the battery is among the most expensive parts, replacing it will be costly; therefore, understanding a little about battery maintenance can save you a lot of money.
How to Reset E-bike Battery
The interior components of the battery are not at all complicated, which is a positive thing in this situation. The majority of batteries have the following internal components;
- Battery Meter
- Battery Cells
- BMS System
Among them only the BMS system can be reset and by resetting it you can reachive the efficiency of the battery.
Step-by-step: How to Do a BMS Reset For an Ebike Battery
The only time your BMS should need to be reset is when you add or change batteries. Let’s start straight away because resetting the bike battery can be difficult. Two methods for doing a battery reset are internal BMS reset and reverse charging.
In our situation, we’ll concentrate on the internal reset because it’s simple and requires no special tools. In steps, let’s examine the specifics:
Step 1: First, turn off the power.
To reset it, You don’t have to turn off your bike entirely—just flick the huge master toggle on the side of your control box. Before trying a reset, ensure no electricity is running through the device.
Step 2: Loosen the battery’s outer casing screws.
To open the battery’s top cap, you’ll need to use your screwdrivers. The top cap is often held in place by a few screws. This will provide you access to the battery’s interior, where you will discover the BMS, battery cells, and the connections that bring everything together.
Step 3: Remove the connectors from the BMS chip.
Deep inside the battery container, the BMS and battery cells are kept secure. You should therefore gently slide everything out just a little bit to make it easier to work with. The idea is to get the BMS out so you can closely inspect it.
Step 4: Cut the wire harness off.
Cut the wire harness precisely.
Step 5: Connect the charger to the battery.
Now, connect your charger to the battery.
Step 6: Reattach the wire harness
After that, reattach the wire harness to the BMS and fasten each component in the battery casing.
Step 7: Check if its work
Check the battery to see whether it is working properly again. Remember to test the battery’s ability to charge and discharge.
E-bike Battery Check Table Chart
Recheck your voltage measurement after doing the reset. The issue has been fixed if you discover that the voltage measurements are accurate and consistent. The BMS must be changed, or you must go to the closest electric bike shop if the readings keep jumping. Typical Lithium Ion Battery Voltage Ranges are listed below.
Key:
- Nominal – Typical operating voltage
- Cutoff – Voltage when the battery is fully discharged
- Full – Voltage when the battery is fully charged
| Battery Chemistry | Abbreviation | Full | Nominal | Cutoff |
| Lithium cobalt | LCO Li-cobalt ICR LiCoO2 | 4.2 V | 3.6 V | 3V |
| Lithium manganese | IMR LMOLi-manganese | 4.2 V | 3.7 V | 3V |
| Lithium aluminum | INR, NMC | 4.2 V | 3.6 V | 3V |
| Lithium phosphate | LFP | 3.65 V | 3.2 V | 2.5V |
| Lithium aluminum | NCA, NCR | 4.3 V | 3.6 V | 3V |
| Lithium titanate | LTO | 2.85 V | 2.4 V | 1.8V |
What Is a Battery Management System (BMS)?
A microcontroller used in lithium-ion batteries regulates charging, overcharging, and discharge. These devices are known as BMS (Battery Management System).
In many circumstances, lithium-ion batteries will recover on their own after being fully depleted and recharged; if not, resetting them is an option.
Plan accordingly because the full recovery could take up to 24 hours. Before taking matters into your own hands, check with customer care and ensure you understand the warranty terms if your battery hasn’t recovered after being cycled twice with no improvement.
What is the Function of the BMS on Your E-bike?
The battery management system, or BMS for short, manages the batteries that power your e-bike system, precisely what the name implies. The average biker doesn’t need to understand BMS systems beyond that;
if your battery is experiencing significant performance problems, a bad BMS is likely the cause. Here is a concise explanation of BMS systems from the best electric bike for more passionate bikers who want to comprehend every part of their e-bike system.
How To Test Your E-bike BMS?
You can follow these two steps to test your e-bike BMS.
Step 1: Before opening the battery, double-check the voltage.
To accomplish this,
- Turn on the battery first.
- Place the multimeter’s negative side, typically black, on the negative side of the battery to measure the voltage.
- Place the positive side of the multimeter, which is often red, on the battery’s positive side.
- If the numbers fluctuate (jump higher or lower), the battery has a problem, and you need to determine whether the BMS or the battery cells themselves is the issue.
Step 2: Verify that the battery cells are functioning correctly without the BMS.
The steps to ensure it are as follows:
- Turn off the battery.
- Remove the battery’s outer frame screws.
- Wear gloves
- Affix the positive side of the multimeter to the positive side of the battery cell assembly.
- Put the multimeter’s negative side on the side linked to the cell assembly.
Step 3: Testing the BMS chip directly is the final step.
This is how to do it.
- Place the multimeter’s positive side on the side that is attached to the positive terminal of the battery cell assembly.
- Connect the multimeter’s negative side to the BMS’s negative side, which is connected to the controller and the motor.
Why Would You Need To Perform A BMS Reset?
Resetting a battery management system may be necessary for a variety of reasons.
- First, the issue may be with your battery. Your e-bike battery specifically isn’t operating as it should. A BMS reset can be precisely what you need in this circumstance.
- The battery management system may occasionally need to reset to begin your preferred battery upgrades. A battery reset isn’t always just for urgent battery adjustments and repairs.
What Tools Do You Need To Reset A BMS?
You might want to look for and get a few tools before you start resetting your BMS. You’ll need some electrical tools because you’ll be fiddling with the circuit board and battery’s wire harness to execute a reset.
1. Wire Cutters
Wire cutters might also be helpful in a severe battery failure. Though it’s not always possible to prevent it, replacing electrical and black wires is difficult.
2. Black Wire
If the damage to your BMS is the cause of your e-bike battery problems, you will also need some black wire to replace any damaged ones in addition to wire cutters.
3. Barrel Jack
A DC barrel jack for managing your unique wiring may also be necessary for battery problems prevalent in e-bikes.
4. Multimeter
It will be crucial to use additional electrical instruments, such as a multimeter measuring tool, to prevent an erratic motor once the operation is finished and to be safe.
Battery Error Codes
When the battery senses a problem, it generates an error code. When this happens, the battery will stop working. Some errors can be recovered from, and some cannot. Some of the battery error codes are listed here.
Number of Flashes – 3
Solution – Reset the battery, then leave the lights on.
Number of Flashes – Reset, then finish doing the charger test.
Solution – 4
Number of Flashes – 5
Solution – Allow to cool
Number of Flashes – 6
Solution – Bring the battery inside to warm it up and reset it.
Number of Flashes – 7
Solution – Allow to cool, then reset before attempting to charge again.
How Do You Reset a Lithium Ion Battery?
A lithium-ion battery needs to be reset if it has been completely discharged for an extended length of time or if it is losing its charge quickly. The steps to reset lithium-ion batteries are listed below.
- Use the lithium-ion battery-powered device until the point of battery exhaustion.
- The device’s power cord should be plugged into an outlet. Connect the multimeter’s negative side to the BMS’s negative side. The lithium-ion battery should be placed in the charger. Connect the charger’s power cord to a power outlet.
- Watch for the gadget or battery charger’s “Charge” or “Power” light to turn on.
- Till the “Charge” or “Power” light goes out, allow the lithium-ion battery to charge fully.
How Do You Reset a Bosch E-bike Battery?
To regain the entire operation of the Bosch battery pack, reset it using these quick and basic methods.
- First, take the battery pack off of the battery mount.
- After that, press the On/Off button for the battery option for around ten seconds.
- The final step is reinstalling the battery pack and power on the electric bike.
How Do I Know If My BMS Is Bad?
You suspect an issue with the BMS. Is it simply a hunch? A bad decision will lead you in the wrong direction. Only these three steps will allow you to discover the truth:
- Connect all wires.
- The white pin of the BMS terminal should be measured. If the volt equals the cell’s actual volt, the BMS is correct.
- Connect the two points of the battery with the multimeter’s black and red probes. Zero=BMS is ok. There is nothing wrong.
FAQ
Can You Restore a Lithium Battery?
YES. According to researchers at the Department of Energy’s SLAC National Accelerator Laboratory and Stanford University, a dead lithium-ion battery can be revived.
What happens if a lithium battery goes dead?
Rechargeable Lithium-Ion batteries have a limited lifespan and eventually lose their charge capacity. When this battery loses capacity, the amount of time it can power the e-bike reduces.
Do you need a BMS for an E-bike?
YES. Without a BMS, individual cells can overcharge, explode, or drain too far.
Can you charge a lithium battery without BMS?
Yes, lithium batteries do not require a battery management system (BMS) to function.
Does BMS drain the battery?
Yes! A BMS with current protection will almost probably need a maximum continuous current.
Conclusion
It’s safe to say that learning how to execute a BMS reset is now a must-have skill for any e-bike owner. Having that skill would save you a lot of time and money if you ever had a battery that refused to charge or discharge properly.
References:
- E-bike Battery Manual Download
- Battery Error Codes
- Read on Scientists can restore lifespan of a dead lithium battery
- 8 Steps on How To Build An Ebike Battery: Complete Guide
