New battery can charge an electric car in 10 minutes
One of the reasons electric cars are still not very widespread is that they can take hours to charge. But that may soon change: researchers at Pennsylvania State University have developed a new lithium-ion battery that charges in as little as 10 minutes. Read More
Penn State
(c) Penn State University
One of the reasons electric cars are still not very widespread is that they can take hours to charge. But that may soon change: researchers at Pennsylvania State University have developed a new lithium-ion battery that charges in as little as 10 minutes.
Do you drive an electric vehicle? If not, you are part of the majority – a majority that is worried about long charging times and running out of power with no way or time to recharge. The latter is often referred to as “range anxiety” and is considered a major barrier to widespread adoption. This is exactly the issue the new battery could help solve.
The problem: long charging times and limited range
Depending on the type of charger or battery used, an electric car can take anywhere between 30 minutes and 20 hours to charge. In 2018, the median range of electric vehicles was calculated to be a modest 200 kilometers. Even Tesla’s fast-charging stations take 45-50 minutes for a recharge, still five times longer than the mere 10 minutes needed to fill the tank of a typical fuel-burning sedan for a 650 km range. The new lithium-ion battery developed by researchers at Pennsylvania State University, by contrast, comes close: it can be charged in 10 minutes for at least 320 km of driving.The key to quick charging is heat
At the basis of this innovation is a simple law of physics: ions move faster at high temperatures, allowing for faster charging. But temperature is a delicate issue when it comes to lithium-ion batteries which has made fast charging impossible so far. Fast charging lithium-ion batteries at high temperatures above 60 degrees Celsius degrades the battery, as materials inside start to react with each other. On the other hand, fast charging lithium-ion batteries at lower temperatures, even at 30 degrees Celsius, can severely limit battery life due to the potential formation of lithium deposits around the anode known as “lithium plating”.
The solution found by leading researcher Chao-Yang Wang and his team involves heating the battery at 60 degrees Celsius for 10 minutes and then rapidly cooling it to ambient temperatures. The method charges around 80 percent of the battery and prevents both the lithium spikes and the degradation caused by longer periods of heat. According to researchers, performance can be maintained throughout 2,500 charging cycles – the equivalent of driving a million kilometers.
Nickel foil does the trick
The secret to quick heating is thin nickel foil. One end of the foil is attached to the negative terminal of the battery while the other end is extended “outside the cell to create a third terminal”. “A temperature sensor attached to a switch causes electrons to flow through the foil” thereby rapidly heating the foil – and the inside of the battery, according to a Penn State press release. The battery could then be quickly cooled using the cooling systems already integrated into cars.
Making this technology scalable, however, might still take two or three years of additional testing and evaluation to ensure the method’s safety, according to Chao-Yang Wang. The batteries used in the experiments were much smaller than those in cars, so it is unclear whether the method can be replicated in larger batteries. Moreover, all battery manufacturers would have to standardize nickel foil plating for such batteries to go mainstream, and all charging points would have to be upgraded accordingly. But the
researchers are optimistic and have already started working on a new goal: charging electric vehicles in just five minutes.
