Using a clean eraser or other material cleaning tool, gently wiping metal contacts on lithium batteries and phones can help improve charging conditions and power supply durability. Automatic shutdown of the old cell phone lithium battery should be firmly wrapped with plastic wrap. Pack as close as possible. The inside and outside of the battery are divided into three layers. Ensure that the battery is in a vacuum state. The plastic packaging is then coated with three layers of newspaper to completely seal the lithium battery. Put it in the freezer. After 48 hours, the batteries were removed and the six layers of paper film were removed one by one. Lithium batteries have no surface swelling or deformation caused by freezing. Let cool for a while before charging.
