Here a few situation that might require a bit more explanations:

Battery turns off during the assembly

After having tightened the 4 screws of the pack and connected the antenna, you might sometimes see the battery switch off. If it doesn't wake up when pressing on the Reboot button (white on the front face of the BMS), then you should have your battery completely wired (antenna, white connector and 2 power connector) and then plug the charger. This should wake it up.

 

Explanation: there is mode called UVLO that protects the battery from deep discharge. It turns everything off in the BMS not to drain the battery id one cell has a voltage bellow 2.2V. During the assembly it is possible that a false voltage measurement has triggered this. 

 

I cannot connect in bluetooth with the app

 

We are still in development so first try on another platform (other phone if you have, or with your computer if you are using Chrome).

You should make sur the antenna is well plugged. 

Also, as the current protocol is quite sensitive, try to remove everything that could hide the antenna (located in the discharge connector block): remove the battery from the support and remove the charger.

I have the OV (Over Voltage) after the first charge

OV means Over Voltage, which means that one cell has reached the limit we set before the others.

Let's take an example: you had well balanced cells after the assembly (left image) and after the charge you find yourself with a level that is higher than the other and has triggered an OV (right image):

If the cells are new, this likely means that on the 10th group (or stage), one cell is not making good contact (contacts not tight enough, or dirt on the contact ball), so there are only 3 cells on this group, causing them to charge faster than the other groups.

What to do:

• Disassemble the battery while leaving all the cells in their place.

• Remove only the cells from group 10 (numbered on the contact plates as 10-1, 10-2, 10-3, 10-4).

• Measure the voltages; one of them should have a voltage lower than the other three (which confirms the problem).

• Clean the cell contacts and lightly scrape the surface of the 8 contact balls with a screwdriver (just a very light scratch).

• Do not put the cells back if the voltage difference is substantial, as this would cause a strong current between them to rebalance.

• To charge the cell that is too low, there are two options:

  • If you have an individual lithium cell charger, you can charge the cell until its voltage is close to the other three, within 0.05V.

  • Otherwise, place only the cell to be charged in the cell holder, close the battery completely, and check on the app that everything is connected (you should see group 10 with the voltage of the single cell).

  • Use the charger to charge; the single cell 10 should charge faster than the others and quickly catch up (this assumes you are using a 2A charger or less, definitely not more, and that you have Samsung 35E cells which should accept charging at 2A).

• Once all the cells are roughly at the same voltage again, put back the other three cells and close the battery.

• The battery may be slightly unbalanced in voltage, but the BMS will work to reduce the difference, which may take a few days.

If you want, I can also help you with tips on how to safely handle and maintain lithium batteries!

I have some bug, need to update the battery firmware

Keeping your e-bike battery's firmware up-to-date is crucial for optimal performance and compatibility with new brands.

There are two ways to connect your battery to Wi-Fi for automatic updates:

Method 1: Using the Mobile App (Recommended)

1. Download the "My Gouach" App: Available on the App Store. 

2. Wake Up the Battery: Tap the battery to turn on its LED.

3. Connect via Bluetooth: Use the app to find and connect to the battery.

4. Configure Wi-Fi: In the Bluetooth app, set the Wi-Fi SSID and password in the menu. Ensure accuracy to connect successfully.

Method 2: Recovery Mode

1. Create a Specific Wi-Fi Network: Name the network "Gouach Maintenance" with a given password.

2. Use a Router or iPhone: Set up the network using a router or share your iPhone's connection. Rename your iPhone to "Gouach Maintenance" and set the correct password.

With these methods, your battery will connect to Wi-Fi and automatically update. Stay connected for the latest features and alerts.

Here is a video on how to set this up on Iphone.

This is what you should see when the battery updates its firmware: