We already have batteries capable of operating in extremely hot or cold conditions. Key: lithium ion

What ice? No problem. That asphalt almost looks like a heated kitchen tray? Nothing happens either. A group of researchers developed in California Lithium ion batteries That operates at a more than respectable level with extreme temperatures, from freezing values ​​to those reached during the worst heat waves. And for the sample, button: In the lab, the prototypes held 87.5% of their energy at -40°C and 115.9% at 50°C.

innovation University of California San Diego Leaves more than a simple anecdote or a strange fact. Equipped with batteries that are more resistant and capable of high charge accumulation, electric vehicles can also perform better in harsh climates: travel away on one charge in lower temperatures or rely less on cooling systems that prevent vehicles from overheating when driving in extremely hot environments.

the key, Zheng Chen’s detailsThe nano-engineering professor works to ensure smooth operation in places where summer brings out stifling temperatures. Battery packs are usually underground, near hot highways. In addition, it is heated only with the passage of current. If they cannot tolerate such heat to high temperatures, their performance will rapidly deteriorate,” adds the expert from the center’s College of Engineering.

From the coldest winter to the hottest summer

In addition to measuring how well they retain their energy capacity in extreme temperatures, the researchers also found that the batteries maintained their High levels of efficiencyand 98.2 and 98.7% at -40 and 50 °C values, respectively. Thanks to its characteristics, the devices can undergo more cycles of charging and discharging before turning off.

How did Chen and his colleagues develop batteries that could handle both the bitter cold and the worst summer heat wave? They explain that the key lies in the electrolyte. It is made from a liquid solution of Dibutyl ether Mixed with lithium salt. A special feature of dibutyl ether is that its molecules are weakly bound to lithium ions. point out.

The result: batteries with good sub-zero performance and heat resistance.

Another advantage of the electrolyte is that it is compatible with it Lithium sulfur batteriesIt is rechargeable and has a lithium metal anode and a sulfur cathode. Their low energy densities and costs make them an essential part of next-generation batteries: they can store up to double energy per kilogram of current lithium-ion batteries.

“It can double the range of electric vehicles without increasing the weight of the battery pack. In addition, sulfur is more abundant and a less problematic source than the cobalt used in the cathodes of conventional lithium-ion batteries,” Add.

Of course not all is well.

In lithium sulfur batteries, the cathodes are usually dissolved and the anodes are dissolved prone to the formation of dendritesFilaments can short circuit, causing batteries to last only a few dozen cycles. The problems are also exacerbated when the weather is very hot. With the development of the electrolyte in California, Part of the problems.

“It helps improve both the anode and anode sides while providing high conductivity and interfacial stability,” Chen ditchwhich he has already tested in the lab.

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