Scientists at Stanford University have developed a smart lithium battery that can send alerts before it gets overheated and bursts into fire. Lithium cells are not just used in everyday consumer electronics such as phones, laptops and other devices; it can also be found in automobiles and airplanes.
Over-charging happens when a battery is powered up too fast or when the temperature is extremely low, thus causing lithium ions to pile up on the anode. The buildup called dendrites, can enter the separator and make contact with the cathode to eventually cause the battery to short.
A standard lithium-ion battery has a carbon anode and a lithium metal-oxide cathode separated from each other by a very thin layer of polymer. If the last mentioned component is damaged, the battery could short-circuit and set fire to the flammable electrolyte solution contained in the cell.
Also see: New battery for safer gadgets developed by Cornell researchers
Detailed finely in the journal Nature Communications, the Stanford University researchers’ early-warning system is capable of discovering problems which occur during the normal operation of a battery. It cannot be made to detect issues in cells damaged in a collision or other similar accident, in its present avatar.
Safety concerns surrounding lithium-ion batteries have been around for ages. Sony faced some trouble with consumer laptops catching fire in 2006 and in 2013, the new Boeing 787 Dreamliner fleet was grounded temporarily by the aircraft company after battery packs in two airplanes burst into flames for unknown reasons.
The newly developed smart lithium battery uses a nano-layer of copper on one side of a polymer separator. The copper plays the part of a sensor, enabling the voltage difference between the anode and the separator to be measured. The voltage drops to zero when the aforesaid dendrites touch this third layer.
Manufacturers could implement the safety system in such a way that users get a text about the lithium battery in their phones being damaged on their handsets itself, well in advance of the cell bursting into flames.