1. First open the screws on the four corners of the battery and open the top cover. You can see that there are four 12V lead acid batteries inside.
2. After clearly memorizing the battery circuit, use a soldering iron to remove the battery wire. Pay attention to prevent the battery from shorting during operation.
3. Finally, after removing all the old batteries, insert the lithium battery, connect the battery terminals and wrap it with insulating tape.
About twelve
If the battery is full, it can probably do about 12 screws, because this thing is also quite labor intensive and consumes electricity. Under normal circumstances, you may only be able to add three or four salts before running out of power.