Employees of St. Petersburg State University have created a new type of polymer battery cells. Batteries based on it charge an order of magnitude faster than modern lithium batteries, are resistant to cold and contain a minimum amount of environmentally hazardous substances. At the same time, there is nothing in such a battery that could catch fire or explode if the operating conditions are violated.
It took three years to develop a new polymer from which to make a battery cathode with such alluring properties. A description of this compound, its characteristics and laboratory test results are presented in the peer-reviewed journal Chemistry Europe. The article was published a few months ago, but for some reason, the public noticed a curious domestic development only now.
As the head of the research group that created this material, Professor of the Department of Electrochemistry of St. Petersburg State University Oleg Levin, explains, the idea arose back in 2016. He and his colleagues started developing promising polymer electrodes for lithium-ion batteries with the support of the Russian Science Foundation. The result of the work was the understanding that such materials have two directions of development: they can both serve in the protective layers of conventional batteries, and play an active electrical storage role in promising cells.
After screening out unstable compounds during a series of experiments, Russian scientists got a workable version. It is a complex polymer based on a long chain of nickel complexes with ligands (salen, NiSalen). Nitroxyl fragments - organic radicals containing nitrogen and oxygen - are attached to the microscopic thread. They are able to quickly participate in redox reactions, that is, store or release energy.
Thus, new batteries do not use lithium compounds, which are responsible for the high risk of battery fire due to physical damage, overheating or short circuit. Scientists from St. Petersburg State University applied common graphite-based solutions as an anode. But in the future, this element can also be improved by creating a more suitable material.
In laboratory tests, the polymer created by domestic specialists has shown itself to be impressive. After two thousand charge-discharge cycles, it retained two-thirds of its original capacity. One of the key advantages of the novelty, in addition to increased safety, is temperature resistance. According to Levin, such a battery works perfectly without changing its properties down to minus 40 degrees.
Naturally, nothing comes out for free. Since metal compounds are used that are heavier than lithium, the specific capacity of this cell is 30-40% lower than that of modern batteries. It is possible to increase the indicator, but you should not expect radical improvements - chemistry with physics cannot be fooled. On the other hand, this disadvantage is more than compensated for by the fast charging speed - ten times faster than the lithium ion. Now scientists are working on the creation of methods for the industrial production of a new polymer, the first results can be expected within a year or two.