Even while electric vehicles are considered green options (as opposed to petroleum-based vehicles), there has been some valid concern about the nature of the batteries used in EVs. The most popular, the Li-ion battery – let’s face it – is not the most eco-friendly.
The clean energy brigade is, however, working on new battery technologies that would be less harmful to the environment. The sodium ion battery has emerged as the most popular as it is less expensive and greener in its quintessence.
Sodium is plentiful and cheap, but its limited battery performance has so far made it difficult to apply on a large scale. But now a breakthrough is being claimed by a research team at the Department of Energy’s Pacific Northwest National Laboratory (PNNL). He claims to have developed a sodium-ion battery with greatly extended longevity in lab tests. The findings provide a promising recipe for battery use in the electric vehicle industry and also store energy from the sun.
Explanation: The new sodium ion battery technology
In a statement, the PNNL, citing research leader Jiguang Zhang, a pioneer in battery technologies with more than 23 patented inventions in energy storage technology, said: “We have shown in principle that sodium-ion batteries have the potential of being a long-lasting product and eco-friendly battery technology.”
In general, as a battery goes through repeated charge and discharge cycles, it loses its ability to hold a charge. In current sodium-ion battery technologies, this process happens much faster than in similar lithium-ion batteries.
But the new sodium ion battery technology developed at PNNL retains its ability to charge longer than the previously described sodium ion batteries.
Scientists have supposedly accomplished this by changing the cathode material and adding an entirely different charge carrier (which is thought to be the electrolyte, the ‘blood’ that keeps energy flowing in a battery). By cleverly tweaking the ingredients that make up the battery’s liquid core, scientists were able to avoid the performance issues that have plagued sodium-based batteries.
The new ‘electrolyte’ also generates an ultra-thin protective layer on the positive pole (the cathode) which contributes to the added stability of the entire unit.
Sodium ion battery and EV industry
“In laboratory tests, the new design has proven to be durable, maintaining 90% of its cell capacity after 300 cycles at 4.2V, which is higher than most previously reported sodium-ion batteries,” the PNNL said. .
The new sodium ion technology also uses a natural fire extinguishing solution that is also impervious to temperature changes and can operate at high voltages.
Even now, sodium-ion technology still lags behind lithium in energy density. But its stability in the face of temperature changes and long life cycle certainly make it attractive to the EV industry, especially for lightweight EVs and even grid energy storage.
Sodium-ion cells may not immediately surpass traditional lithium-ion batteries, but they have a number of benefits for charging, maintaining energy, and helping to promote cleaner energy.
For the record, last year, CATL, the world’s largest battery manufacturer, introduced its first-generation sodium-ion battery pack, as well as an AB solution that integrates sodium-ion and lithium-ion cells into a single package.
In India, Reliance Industries announced the acquisition of UK-based Faradion, a company working on the use of sodium ions in rechargeable batteries.