The current generation of lithium batteries has several weak points. One of these points is the relatively speedy decay of capacity, a particularly annoying characteristic if these batteries are to be used in electric vehicles, for example.

To improve on this weakness, scientists decided to take a look at how organisms handle the decay and aging effects of free radicals and reactive oxygen in nature. They obtained some fascinating and useful findings.

The team shared their findings in the Journal of the American Chemical Society.

One of the problems found with contemporary lithium ion batteries is gradual decay of capacity - *Image Credit: Have a nice day Photo via Shutterstock*

Electrolyte decay

Electrolytes form the medium that connects the two poles (anode and cathode) of an electrochemical energy carrier or cell (a battery in this case).

The electrolyte can be a liquid or a paste-like material, depending on the kind of battery. Still, its purpose is always the same: transporting positively charged ions between the anode and cathode.

In contemporary lithium-ion batteries, chemical decay of the electrolyte happens throughout the cycling of the circuit by oxidation of highly reactive oxygen.

On top of that, decay occurs as the result of interaction with so-called 'free radicals.' Free radicals are molecules with unpaired valence electrons (electrons located in the outer shell associated with an atom), making them highly chemically reactive.

Preventing lithium battery decay

Current attempts at reducing lithium battery decay generally comprise of engineering solutions such as utilizing a solid electrolyte instead of a liquid one or creating a physical barrier to reduce the speed of degradation. Despite all these efforts, substantial suppression of chemical decay has not yet been achieved.

Because oxygen is one of the elements capable of drawing electrons from other atoms and molecules, damage and degradation of the aforementioned kind happens almost everywhere in nature. Think of iron that rusts or apples that get brown, all of which are the result of oxidation.

Nature has devised a wide variety of solutions to combat oxidation decay. Typically, organisms create various types of enzymes that collect free radicals and oxygen to prevent damage.

Professor Guanglei Cui, a lead researcher, connected to the Qingdao Institute of bioenergy and bioprocess Technology, stated that he and his team came up with the idea to try to copy what nature already does and use it to improve battery technology.

Taking inspiration from the mechanisms that organisms employ to combat oxidation in nature, the team created a 'photostabilizer' in the form of a relatively straightforward, anti-aging binder additive that can be added to the electrolyte inside batteries. Inside the battery, the additive will collect free radicals and singlet oxygen atoms to prevent/decrease the speed of decay.

The underlying chemical mechanism of the antiaging binder comprising PS and PVDF - *Image Credit: ZHANG Huanrui*

Initial theoretical calculations and experimental examination have shown that the nature-inspired photostabilizer mechanism shows improved electrochemical performance, even at higher temperatures in compersion to conventional lithium batteries.

According to Professor Cui, these results may be the beginning of a new template for handling the chemistry of all kinds of rechargeable batteries that suffer from chemical degradation.

Based on the successful preliminary results for their anti-aging binder, the science team has set its targets on commercializing their nature-inspired anti-aging binder, hoping to make it a component for a new generation of battery technology that should eventually replace conventional lithium-ion based batteries.

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