After the lithium battery of a mobile phone or electric car decays, it is often scrapped. Just like a person getting sick, battery decay is just a decrease in lithium ions, while other parts remain intact. Can it be “revived with one shot” to replenish lithium ions?
This seemingly “crazy” idea has been realized in the laboratory by the Peng Huisheng/Gao Yue team of the Department of Polymer Science at Fudan University. Through “precision treatment”, lithium batteries are still close to the “healthy” state at the time of leaving the factory after tens of thousands of charge and discharge cycles, and the cycle life has been increased from the current 500-2000 cycles to more than 12000-60000 cycles, which is the first time in the world. Today, this major original result was published in the international authoritative academic journal “Nature”.
Breaking the battery design principles
Lithium batteries are widely used in electronic equipment, transportation vehicles, energy storage power stations, etc., which has greatly changed people’s lifestyles. Lithium ions are naturally scrapped after being consumed to a certain extent.
Innovation is a challenge to “convention”.
“In fact, I had this idea when I was studying for my doctorate. It was not until I joined Fudan University, where there is a good “soil” for scientific research and I have my own team, that I began to implement it.” Gao Yue, a young researcher at the Department of Polymer Science of Fudan University, told reporters that although he is engaged in basic scientific research, he hopes to solve the most pressing problems in the energy field.
At present, electric vehicle batteries can only guarantee a high-performance life of 6-8 years; low-temperature use will accelerate the deterioration of batteries; the upcoming large-scale battery scrapping may cause environmental pollution and waste of resources…
In Gao Yue’s view, the future will be a highly electrified world, so it is urgent to change battery technology to achieve large-scale long-term energy storage.
Innovation comes from cross-border inspiration.
From the total synthesis of natural products to immunotherapy, from 3D printing to organic materials and devices, cross-border research experiences have shaped Gao Yue’s “scientific imagination”.
Without any research precedent to support it, the team proposed a bold idea – breaking the traditional design principles of batteries and “injecting” active lithium ions into batteries.
AI-assisted screening of molecules
First, we need to find suitable active lithium ions. If we follow the traditional research paradigm, that is, relying on theory and experience to design, it will be a protracted process.
Thanks to Fudan University’s deepening of scientific research paradigm changes and promotion of scientific intelligence ecological construction, the Department of Polymer Science has established a scientific intelligence center to support teachers and students to use AI to explore the unknown molecular world.
With the assistance of AI, the research team screened and artificially synthesized lithium ion carrier molecules – lithium trifluoromethylsulfinate from more than 3 million virtual molecules. The researchers called it “lithium drug”.
The reporter was able to see its true appearance in the laboratory – a white powder. It can be dissolved in the electrolyte and injected into the waste and decaying battery after “injection”. After charging, the lithium battery will be “revived”.
“Lithium drugs” are like a “porter” that only transports lithium ions without changing the original structure and production method of lithium batteries. In theory, they will not add any possible risks, thus achieving non-destructive battery repair.
In addition, this “out of thin air” white powder is not only easy to synthesize but also low-cost, and can be prepared on a large scale in the future.
Cooperation with top international battery companies
How long can a lithium battery be used after “one shot”?
“The attenuation rate after 12,000 charge and discharges is 4%, which is equivalent to an electric vehicle battery that is charged twice a day and can be used for 18 years, and the attenuation rate after 18 years is 4%. If the existing electric vehicle battery is charged twice a day, the attenuation rate will reach 30% after only 2.73 years.” Gao Yue said.
This means that after “multiple injections”, lithium batteries will no longer have the concept of scrapping in the future, and can also help large-scale energy storage.
In addition, the binding rule that lithium batteries must contain lithium when they are made has also been broken. “At present, many green materials that do not contain lithium cannot be used to make batteries. In the future, we can directly inject lithium ions into batteries. In this way, it is possible to build batteries using environmentally friendly materials that do not contain heavy metals.”
When can this original technology be put into practical use?
Gao Yue told reporters that the relevant verification experiments were completed on real battery devices rather than models. The team is carrying out large-scale preparation of lithium ion carrier molecules and cooperating with top international battery companies to strive to transform this technology into products and commodities as soon as possible.