DENDRITES ? Fire-starting battery dendrites go with the flow https://www.chemistryworld.com/news/fire-starting-battery-dendrites-go-with-the-flow/3008867.article "When a lithium–ion battery charges, lithium ions travel from the cathode to the anode; the ions flow the other way during discharge. At a lithium metal anode, lithium ions leave and return to the surface unevenly. This means that after several charging cycles, spiny projections called dendrites begin to grow from the electrode’s surface. As these lithium dendrites grow, they can pierce the membrane separator in the middle of the battery, touch the cathode and short circuit the cell. This can starts fires." Three Ways That Lithium Dendrites Grow https://www.designnews.com/electronics-test/three-ways-lithium-dendrites-grow/78500767259733 "In the study, when the separator was pierced, the battery was in danger of catastrophic failure, although its perilous condition was not necessarily apparent. Bai said, “Our unique transparent cell revealed that the voltage of battery could look quite normal, even though the separator has been penetrated by a lithium metal filament. Without seeing what is happening inside, you could be easily fooled by the seemingly reasonable voltage, but, really, your battery has already failed.” Which dendritic growth mechanism occurs depends not only on the level of current, but also the age and charge history of the lithium battery. The thresholds for the dendritic growth types become lower as the battery ages. In addition, there is a push to faster charging, particularly for EVs, and the higher currents required can result in differing types of dendrite formation. If solid state lithium batteries are to become viable, the results of the study will need to be considered to control the differing types of dendrites that are formed. “Battery operation is highly dynamic, in a very wide range of currents. Yet its disposition varies dramatically along the cycle life. That is why this becomes necessary,” Bai said."