How to distinguish between new lithium batteries and used lithium batteries
According to German media reports, a small life suggestion has been circulated on the German website recently: In order to determine whether a battery is an empty battery that should be discarded, people can throw the battery 20 cm from the ground. If the battery rebounds after touching the ground If it is very high, the battery is an empty battery. If the battery does not pop up, it proves to be a new battery.
This incident aroused the interest of scientists. They re-verified in the laboratory, using a slow-motion camera to record the movement trajectories of empty batteries and new batteries falling from the table. The results show that the height of the empty battery bounced from the ground is indeed higher than the height of the new battery bounced.
In order to further verify the rationality of this statement, researchers at Princeton University in the United States conducted more in-depth research. The researchers let two batteries fall in a plexiglass tube, and in the process measured the first and second rebound heights. In addition, the researchers also added several control groups in the experiment: three batteries with 70%, 80%, and 90% power.
In the end, the experimental results show that whether it is an ordinary disposable battery or a storage battery, as long as the battery has half of its power, it can be bounced to a certain height by the ground, but the height is different. Researchers explained this phenomenon that the positive electrode of a household battery is composed of zinc elements, which are present in the battery gel. The battery gel will reduce the impact of a fully charged battery on the ground, so a fully charged battery will often not bounce off the ground.
In the process of battery discharge, a large amount of zinc element contained in the battery reacts with oxygen to form zinc oxide, which is a rigid substance that can make the battery's rebound height higher.
At the same time, researchers also said that this experiment cannot be used as a criterion for whether batteries should be thrown away. The real significance of the experiment lies in how to distinguish between used batteries and new batteries.