Researchers from IIT Guwahati have developed a technique which can precisely estimate one of the most important battery internal states known as SOC, short for state of charge.
Researchers from IIT Guwahati have developed a technique to improve the performance of rechargeable lithium-ion batteries, which power most of the portable devices used today. Their findings were published in the journal IEEE Xplore last month.
What are lithium ion batteries?
The 2019 Nobel Prize in Chemistry was jointly awarded to Stanley Whittingham, John Goodenough and Akira Yoshino for work that led to the development of lithium-ion batteries, which are used in most mobile phones, smartphones, tablets, laptops and power banks, among other devices. The first commercially viable Li-ion battery was created by Yoshino in 1985 who developed on Whittingham and Goodenough’s work.
The Royal Swedish Academy of Sciences notes that the foundation of the lithium-ion battery was laid during the oil crisis of the 1970s, around which time Whittingham started working on developing methods that could lead to fossil fuel-free energy technologies.
Today, most Electrical Vehicles (EV) use Li-ion batteries as well, but are slowly reaching their theoretical limits of being able to provide roughly up to 300-watt hour per kilogram of energy. These batteries can also be used to store solar and wind power, which means that with their widespread use it may even be possible to live in a fuel free society.
Even so, some of the disadvantages of Li-ion batteries include their susceptibility to overheating and their being prone to damage at high voltages since they are made with flammable and combustible materials. Such batteries also start losing their capacity over time — for instance, a laptop battery in use for a few years does not function as well as a new one.
So, what have the researchers now developed?
Researchers from IIT Guwahati have developed a technique which can precisely estimate one of the most important battery internal states known as SOC, short for state of charge.
SOC reflects the remaining capacity of the battery, that is how much more charge can be withdrawn from the battery before it gets fully discharged. The knowledge of remaining capacity helps to optimize battery’s capacity utilization, prevent overcharging and undercharging of the battery, increases its lifespan, reduces cost, and ensures safety of the battery and its surroundings, a press release issued by IIT Guwahati said.
To improve a battery’s lifespan and optimize its capacity, it is important to predict its various states accurately. One of these states is the SOC, which has so far been difficult to estimate. Through their work, the researchers have proposed an approach that avoids overestimation and therefore helps in taking accurate measurements.
Are there alternatives to Li-ion batteries?
Researchers have been trying to come up with alternatives or ways to improve these batteries. In 2019, the Johns Hopkins Applied Physics Laboratory developed a Lithium-ion battery that does not catch fire.
Earlier in January 2020, researchers from Australia claimed that they developed the world’s most efficient lithium-sulfur (Li-S) battery, capable of powering a smartphone for five continuous days — the equivalent of an electric car being able to drive a distance of over 1,000 km.
While the materials used in the Li-S batteries are not different from those in Li-ion batteries, the Australian researchers reconfigured the design of the sulfur cathodes (a type of electrical conductor through which electrons move) to accommodate higher stress without a drop in overall capacity.
Li-S batteries are generally considered the successors of Li-ion batteries because of their lower cost of production, energy efficiency and improved safety. Their cost of production is lower because sulfur is abundantly available.
Even so, there have been some difficulties when it comes to commercialising these batteries, mainly due to their short life cycle and poor instantaneous power capabilities.
Source: indianexpress
