Scientists have discovered a way to bring used batteries back to life and improve their performance by 30%
As rechargeable batteries get used, lithium particles start to move slowly and cannot ‘reach’ the electrodes. Scientists have found a way to solve this problem and reduce the number of charges on mobile devices and electric-powered cars.
US researchers at the US Department of Energy’s SLAC National Accelerator Laboratory and Stanford University have developed a technology to extend the life of lithium-ion batteries by about a third and boost their performance. The results of the discovery have been published in the scientific journal Nature.
How lithium ion batteries work
In a working battery, lithium ions move between the electrodes during the charge/discharge cycle. Some of them are unable to pass through the electrolyte and lose their electrochemical properties as a result. Dense lithium deposits then arise which inevitably leads to a reduction in battery performance.
How do you recharge a used battery?
A method proposed by scientists helps to activate lithium ions if the charging procedure is properly organised. The technology optimises the current battery generation and opens up the prospect of high density energy storage. Its implementation will increase the autonomy of electric cars and mobile devices.
According to Yi Tsui, head of the research group, isolated lithium cannot be classified as a quality material, as it causes battery decomposition and increases the risk of fire. However, when “dead” particles are combined with a negative electrode, a positive effect occurs and they are reactivated.
Theoretical part
Scientists hypothesised that lithium ions can be made active again after a voltage is applied to them. To confirm their conjecture, they prepared a test apparatus (“optical” battery) which can be used to monitor the isolated dense formations during charging.
The results of the experiment
The experiment showed that the particles had minimal activity, shifting very slowly towards one electrode during charging and towards the opposite electrode during discharging.
According to Yi Tsui, this process is reminiscent of a worm being too slow, throwing its front end forward and then pulling its tail towards itself to advance a negligible distance. In the case of lithium, there is dissolution in one part and movement of the material in the other. If it is possible to direct the movement of the lithium “worm” it will eventually “crawl” to the anode and bring the electrical connection back to life, the scientist explained.
Experiments carried out with other types of batteries and the use of computer simulations confirmed the increase in lithium activity as the current strength increased. This made it possible to include a strong discharge stage with a strong current in the stage immediately after the end of the charge. As a result, the clot moved to the required distance to the anode.
Opinion of theoretical physicists
US physicists stress that lithium’s insularity could be a major obstacle to the development of the latest generation of lithium metal batteries. They can store up to ten times more energy but are unstable. The use of new technology could help to overcome this problem.
Who stands to gain from reusing these batteries?
Manufacturers of electric cars might be very interested in this way of improving battery performance, as battery life is critical in this area.
Recall that in mid-December 2021, representatives from Samsung and IBM talked about the possibility of increasing the autonomy of smartphones up to 7 days. This could be achieved by changing the standard horizontal arrangement of transistors in processors to a vertical one.