Is it possible to fix the inevitable energy loss of batteries?

Devices such as mobile phones, laptops, and electric vehicles use lithium batteries as their power source. These batteries are rechargeable but degrade over time. Batteries must have a significant lifetime if they will position electric vehicles over those powered by petrol and diesel.

Every smartphone user knows that as their devices' batteries degrade, it becomes necessary to charge them more frequently. To explain the degradation of lithium batteries, we must understand how they work.

Lithium batteries operate through moving lithium ions that flow through an electrolyte between two electrodes: the anode and the cathode. The cathode is made of a layered lithium-rich material, and lithium ions sit between the layers. The anode accepts the ions from the cathode, and it is usually made of graphite.

The capacity of a lithium battery refers to the maximum amount of energy that it can provide to a device. A battery life cycle refers to the complete drainage and recharge of a battery. The more cycles a battery completes, the more it degrades. Manufacturers are working on finding ways to reduce the degradation of the batteries.

The Korea Institute of Science and Technology developed an electrode pretreatment that minimizes the initial loss of ions in the anodes. The anode is dipped in the solution and displayed near-ideal energy density. The scientists identified that the pre-treatment solutions created earlier would result in the unintended insertion of solvent molecules with lithium ions into the graphite, due to the graphite’s versatile intercalation capability. This intercalation of large solvent molecules caused the structural breakdown of the graphite-silicon oxide composite electrode.

To avoid electrode failure, the scientists created a novel solution using a weakly solvent to decrease the interaction between the solvent and the lithium ions.

This solution allowed the selective insertion of Li ions into the active materials, assuring a constant supply of additional Li to the graphite–silicon oxide composite electrode. The primary Li consumption was fully prevented after the immersion of the graphite-silicon oxide electrode in the solution made by the scientists for around 1 minute, even at a 50% silicon oxide ratio.

This breakthrough is fundamental for the future of lithium batteries.

More information in storage in Mexico.



Entradas populares