Battery De-passivation

(Applies from Firmware 7.0.26i onwards, API 7/NEXT devices only)

What is Passivation? Lithium thionyl chloride (Li-SOCl₂) AA batteries naturally develop a thin passivation layer on the lithium anode when stored for long periods. This layer acts as a protective film that reduces self-discharge and extends shelf life. However, it also increases the internal resistance of the battery, which may temporarily prevent the device from drawing the required current.

What is De-passivation? De-passivation is the process of breaking down this protective layer to restore the battery’s normal chemical activity and allow it to deliver the required power.

When does it happen?

• The de-passivation process automatically begins when the device exits factory mode.

• The Orange LED starts flashing, indicating that de-passivation is in progress.

• It may also occur when factory mode is manually activated via commands.

How long does it take?

• Typically: 30 seconds to 1 minute

• If the device has been stored for a long time, up to 15 minutes

Which batteries does it apply to?

• Only applies to Lithium Thionyl Chloride (Li-SOCl₂) AA batteries

• Not applicable for LiMnO₂ batteries

Benefits of Passivation/De-passivation

• Passivation extends the storage life of Li-SOCl₂ batteries by minimizing self-discharge.

• De-passivation ensures that, after storage, the battery can reliably deliver full performance when placed in operation.

Read more: [Lithium Thionyl Chloride Batteries Passivation]

How to Activate De-passivation After Battery Replacement

Battery replacement usually occurs after the device has been in operation and the batteries have been depleted. Depending on whether the device was in factory mode or user mode, the de-passivation process may need to be triggered manually.

Step 1. Replace the batteries following the [Battery Replacement Guide].

Scenario A: Device was in active use (not in factory mode)

1. Switch the device to factory mode:

   • Send a downlink command to activate factory (transport) mode:

     0x15  Switch to factory (transport) mode  
     DL: 000000000000FF15

   • Request the downlink via extra long press, and verify that the confirmation message (DA) has been received.

2. Once the command is confirmed, the Orange LED will begin flashing, indicating that the de-passivation process has started.

3. Wait until the de-passivation is complete (30 seconds to 15 minutes, depending on the storage time).

4. Exit factory mode and return the device to normal operation.

Scenario B: Device was already in factory mode

• Simply replace the batteries. The device will automatically initiate the de-passivation process (Orange LED flashes).

• Once completed, you can exit factory mode and continue using the device.

Note Before performing the de-passivation process after a battery replacement, we recommend contacting us first to confirm if it is necessary.

• If the batteries were purchased directly from us, we will inform you in advance whether de-passivation is required.

• If the batteries were purchased from a third party, please reach out to us for a short discussion. The need for de-passivation depends on factors such as when the batteries were produced and how long they have been stored before use.