Why Lithium Batteries Explode?
There are three main parts inside the lithium battery.
First, lithium cobalt oxide. When charging the battery, the electrons enter the lithium battery from the outside of the device, and "absorb" the lithium ions in LiCoO 2 lithium cobalt oxide, and flow to the graphite electrode along a certain direction, and accumulate near the graphite electrode. Cobalt oxide itself has a good stable structure, so when lithium ion is absorbed by electrons, it will not affect the part of the electrode itself.
Second, graphite electrodes. It is the current mainstream electrode material. When lithium batteries are charged, as mentioned above, lithium ions accumulate near graphite electrodes. When I use lithium batteries, graphite electrodes release Zhou Cao's lithium ions and return them to cobalt oxides to synthesize lithium cobalt oxides, thus reaching a stable state.
Third, polypropylene materials. The above two electrodes are physically separated, and there are fine holes on the surface to supply lithium ion to penetrate between the two electrodes. Explosion often occurs in this part, and the design of the battery plate itself is thinner. At this time, the production process of polypropylene materials is more demanding. When the polypropylene separator is in trouble, it is impossible to close the fine holes in the middle (the closure rate of the fine holes), and the local contact between the positive and negative electrodes produces thermal effect, which leads to the local temperature rise. The pressure inside the battery rises sharply, causing the battery to explode.
The above is a phenomenon of explosion.
Here's another lithium battery explosion
When more lithium ions are gathered near the graphite electrode, the structure of the graphite electrode is square, and each lattice stores one lithium ion (nanometer level), so that other materials can not "squeeze" in. When the charging voltage rises above 4V, the lattice structure of the graphite will be affected to a certain extent, resulting in grid deformation, collapse and so on. Consequently, a permanent reduction in the number of lithium ions stored will directly lead to a decrease in battery power, and the lithium ions that can not be squeezed into the grid will form fine lithium metal crystals along the direction of the ions coming. These crystals will gradually accumulate and break through the polypropylene barrier, making the fine holes unable to close, thus forming a short circuit explosion of positive and negative electrodes.