A battery separator is a polymeric membrane that sits between the positively charged anode and the negatively charged cathode of a battery. This positioning aids in the prevention of electrical short circuits.
When the electrolyte moistens the membrane, it acts as a catalyst, increasing the movement of ions from one electrode to the other. When the battery is fully charged, ions move from the cathode to the anode, and when the battery is discharged, ions move from the anode to the cathode. Because the membrane regulates the number of ions that move between terminals, it is also in charge of the battery's charge and discharge under ideal conditions. While battery separators let free ion passage, they are not electrically conductive.
However, failure of the battery separator would result in short-circuits thereby fire and explosion of batteries. further, In a battery system, a battery separator is the first element to fail and result in fires.
At Quantum Copper, we are developing a self-extinguishing separator that improves the fire-safety of batteries by preventing the further spread of fires caused by any damage or battery failure.