Sodium Ion Battery Ignites Developers’ Imagination

Sodium battery breakthroughs are rewriting the game and are ushering a new era of the diversification of battery technology.

When they first came on the scene, lithium batteries were widely touted as the future of advanced batteries. However, the success story seems to have lost its sparkle and has hit many roadblocks in recent years. Accidents at lithium facilities coupled with the technology’s limitations have pushed manufacturers to start looking elsewhere for alternatives that can potentially power the battery revolution.

A strong contender on the scene is the sodium ion battery which is energy dense, non-flammable, and operates well in colder temperatures. In fact, industrial heavyweights like CATL and Reliance Industries, after their acquisition of the UK-based sodium-ion specialist Faradion, have already shown interest in taking the technology out of the laboratory and exploring its mass production. As the prices of lithium-ion battery materials soar and predictions of shortfalls loom on the horizon, the sodium ion battery has never looked more appealing.

Sodium Battery vs. Lithium battery

While lithium batteries do have many advantages, lithium carbonate prices have reached all-time highs in recent years. In January 2022 for instance, prices crossed $40,000/tonne for the first time. In comparison, rates at the end of 2021 were at $27,327/tonne according to Benchmark minerals. The rising costs can be attributed to pandemic-related supply-chain bottlenecks, the Russia-Ukraine conflict, and increased demand from businesses.

In the sodium battery vs. lithium battery debate, the scales seem to be slowly tipping in favour of the new sodium battery whose environmental credentials are far superior. As an element, sodium is a thousand times more abundant than lithium. What adds to its appeal is the fact that there is practically an infinite supply of the commodity and the overall costs of its extraction and purification are far lower. Given these factors, the sodium ion battery is expected to be anywhere between 20% to 40% cheaper.

The new sodium battery technology also promises enhanced safety. What makes these batteries particularly exciting are the improvements in terms of performance, density, and cycle rate that we have been witnessing in recent years thanks to a string of innovations. The challenge of course is bringing the technology to scale. On this front, lithium ion batteries have a head start of several decades as large production volumes have led to a significant reduction of costs.

Sodium Ion Battery Breakthroughs

Despite the many advantages of the new sodium battery, its utilisation has been limited due to poor durability. This may be about to change for good as a research team from the US Department of Energy’s Pacific Northwest National Laboratory (PNNL) has developed a sodium-ion battery with a much better shelf life than ever before. The findings, published in the journal Nature Energy, promises to provide a new sodium battery that may one day power electric vehicles and store solar energy.

The electrochemical reactions which keep the energy flowing in batteries get sluggish over time. This process is much faster in existing sodium-ion battery technologies when compared to lithium-ion batteries. The PNNL team were able to address this problem by changing the liquid solution and the type of salt flowing through it to create a new electrolyte recipe.

In essence, the researchers modified the composition of the liquid core of a sodium-based battery and changed its ingredients. In doing so, they were able to tackle the performance issues which plagued such batteries in the past. For the first time ever, scientists have been able to significantly extend the number of charging cycles (300 or more) with minimal loss of capacity (>90% retained) in a coin-sized sodium-ion battery in lab tests.

Another sodium battery breakthrough came fromYan Yao, professor at the Electrical & Computer Engineering department of Cullen College of Engineering, and his colleagues at the University of Houston. Yao has developed a homogeneous glassy electrolyte which makes it significantly more viable to produce sodium ion-based batteries commercially and on a larger scale.

This electrolyte enables reversible sodium plating and stripping at a greater current density. Yao’s oxysulfide glass electrolyte is low cost and easy to fabricate apart from being stable both mechanically and chemically. “The new structural and compositional design strategies presented in this work provide a new paradigm in the development of safe, low-cost, energy-dense, and long-lifetime solid-state sodium batteries,” said Ye Zhang, a research associate in Yao’s group.

Sodium battery: The Industry Takes Note

In 2021, the Indian conglomerate Reliance Industries had declared that its solar unit would buy UK-based Na-ion battery technology pioneer Faradion for GBP 100 million ($136 million), including debt. The move marked Reliance’s sixth acquisition in the renewable energy sector. Under the plan, the conglomerate will build several gigafactories in India by 2024. Faradion CEO James Quinn hinted at Reliance’s Na-ion manufacturing ambitions and said that the plan was to build a double-digit-gigawatt fab. “I think it’s very clear that Reliance is really going all in on sodium-ion technology and building at giga factories level. And this is what the technology needs to be able to scale,” he added.

It is important to note that Faradion was the first company to champion Na-ion battery technology more than 10 years ago. Back then, it had basically no competition. But interest has steadily grown and several companies have since emerged including HiNa Battery Technology (a spinoff from the Chinese Academy of Sciences), Tiamat (which came out of the French National Centre for Scientific Research), Natron Energy (a spinoff from Stanford University in the United States), Altris AB (started by a team from Sweden-based Uppsala University), and China’s Contemporary Amperex Technology Ltd. (CATL)

Despite these advances, looking at the current scenario as a simple sodium battery vs. lithium battery debate might be a bit reductive. As things stand, sodium-ion technology still lags behind lithium when it comes to energy density. However, both battery technologies have much in common when it comes to their structure and working principles. In fact, they often deploy the same manufacturing lines and equipment. In the long run, Na-ion might just turn out to be a complementary technology to Li-ion as opposed to a competitive one.