Many of you probably don't understand what battery depassivation is. Some are even hearing the term for the first time. This short article will provide a definition and explanation.
This phenomenon primarily occurs with lithium-thionyl chloride batteries, which can be stored for up to 10 years from the date of manufacture. However, prolonged storage in a warehouse, storage unit, or simple box causes an insulating film to form on the surface of the lithium metal electrode. This film is nothing more than a buildup of lithium chloride. This process is called passivation. This film can form during manufacturing when lithium comes into contact with thionyl chloride.
The film ensures the battery has a low self-discharge rate, allowing it to be stored for a very long time. However, over time, the film thickens, leading to increased resistance and decreased voltage.
Depassivation is the process of removing a thick layer of deposits from a battery's electrode. To do this at home, you'll need:
- 12 volt lamp. 5 watt.
- Multimeter.
- The battery under test
Now that we have all the components at hand, we carry out the following procedure:
- We measure the voltage under load. Due to passivation, it will be 2.2 volts.
- Continue measuring without turning off the lamp. We need the voltage to be 3 V.
- As soon as the required voltage appears on the tester's display, depassivation is successful! The film will be gone.
This procedure should only be performed before using the device. Otherwise, the battery life will be reduced.
If you don't understand anything, you can watch a video that explains what battery depassivation is!
Great article. Thank you.