As the world is transitioning towards more forms of green energy, there has been a huge focus in recent years on discovering new and affordable ways of storing power. Research teams and organizations are already searching for the next generation of large-scale batteries. When it comes to powering electric vehicles, lithium-ion batteries have remained the preferred choice for manufacturers due to their attributes, such as low maintenance, low self-discharge rate, and high energy density. By 2030, it is estimated that there could be a five-fold increase in demand for metals used in Li-ion batteries, leading to a price increase for electric cars and bikes. However, some of the disadvantages of lithium-ion batteries, such as high cost, volatile nature, temperature sensitivity, and eco-unfriendliness, might limit their adoption in the future. Also, the continued uptake of electric vehicles and scarcity of lithium supplies have led to an increased need for alternative battery chemistries. 

The invention of new sodium-ion battery technology by the US Department of Energy’s Pacific Northwest National Laboratory (PNNL) comes as a massive breakthrough for the electric vehicle industry. These batteries are energy dense, non-flammable, and operate well in colder temperatures. Since sodium is found abundant in nature, they are less expensive than lithium-ion batteries. Besides, sodium-ion batteries are long-lasting, and they are considered to be eco-friendly. The sodium-ion batteries are considered an ideal alternative to lithium-ion batteries for powering electric vehicles as they offer a greater range and carrying capacity. 

How does Sodium-ion Battery Technology Work?

The battery goes through a repeated cycle of charging and discharging, negatively affecting its ability to hold charge. As the electrochemical reactions that keep the energy flowing between the positive and negative electrodes become sluggish, the battery is not able to recharge. However, this process happens faster in current sodium-battery technology when companies use lithium-ion batteries. However, the new sodium-ion battery technology developed at the US Department of Energy’s Pacific Northwest National Laboratory (PNNL) has an enhanced ability to hold charge for a long period. The new technology has been developed by modifying the cathode material and adding a different charge carrier that adds to the additional stability of the entire unit. The current electrolyte recipe developed by researchers extends the number of charging cycles (300 or more) with minimal loss of capacity (>90% retained), which allows sodium ions to pass through while preserving the battery life. This way, the scientists were also able to eliminate the performance issues associated with the previous sodium-based batteries. The new sodium battery technology uses a fire-extinguishing solution that makes it impervious to temperature changes and allows it to operate at high voltages. 

How are Na-Ion Batteries Better than Li-Ion Batteries?

Price 

• Lithium is a scarce element in the earth’s crust; hence its greater demand adds to the price of lithium-ion batteries. 
• Sodium is the sixth-most abundant element on earth; hence it is easy to extract. Besides, the raw materials used for the ternary cathode material of sodium-ion battery are inexpensive compared to those used in a lithium-ion battery. 

Safety

• Lithium-ion batteries are prone to fire if damaged, warped, or subjected to high temperatures. 
• Sodium batteries can operate at a wider temperature range and are non-flammable. Besides, since sodium has no over-discharge characteristics, the sodium-ion battery can be discharged at zero volts. 

Major Developments in the Global Sodium-Ion Battery Technology Market

CATL to Commercialize Sodium-Ion Battery Technology by 2023

Contemporary Amperex Technology Co. Limited (CATL), one of the largest battery manufacturers and top-tier suppliers of batteries for electric vehicles and energy storage systems in China, announced that sodium would play a significant role in the electrified future. By 2023, CATL will start placing sodium cells alongside lithium inside battery packs to power mid-range electric cars. The company aims to make the two elements interchangeable in the manufacturing process to compensate for the lower energy density. The company is also working with the researchers at San Diego to set up manufacturing techniques for solid-state sodium batteries, which would be safer and more energy dense. CATL’s first generation of sodium-ion cells can achieve a gravimetric energy density of 160Wh/kg, which is relatively low than the existing 2170 Li-ion cells utilized in Tesla Model 3 and Model Y vehicles with a capacity in excess of 250Wh/kg.

The new CATL’s Na-ion batteries will be resilient enough to last for thousands of charging cycles that could offer enough power to drive an electric motor. Besides, the energy density provided by these batteries would give EVs enough range for most uses. The Chinese battery manufacturer is optimistic that if sodium-ion cells can be optimized and commercialized, they could offer distinct advantages over conventional Li-ion batteries, such as enhanced safety performance, fast charging, and better operability in cold climates. Since sodium-ion cells can be manufactured using existing battery manufacturing equipment, the company would not have to bear extra costs for factory redesigning.  

Reliance Industries to Lead the Manufacturing and Distribution of Sodium-ion Cells in India

Indian conglomerate Reliance Industries is leading the charge to provide sodium-ion batteries in India with the support of Faradion, the world leader in non-aqueous sodium-ion cell technology. Reliance’s acquisition of Faradion for USD135 million is in line with its aim to commercialize sodium-ion battery technology through building integrated and end-to-end Giga scale manufacturing in India. Incorporating new batteries would make EVs more affordable, an excellent attribute for the cost-sensitive customers in India and other emerging markets. For over a decade, Faradion has been working exclusively on sodium-ion batteries, which are currently able to deliver 160-170 watt-hours per kilogram commercial and are expected to hit 200 watt-hours a kilo soon. 

In India, the government has rolled out subsidies to bring down the cost of electric vehicles, making them cheaper than gasoline guzzlers to promote electrification and reduce carbon emissions. Currently, the EV storage in India is pegged at USD300 million, which is expected to grow, owing to the launch of new electric bikes and rising fuel prices. By 2025, the car market in India is projected to clock 4 million sales volumes, comprising 5% penetration of EVs. The rising adoption will result in explosive demand for batteries, which could create circumstances where the batteries would require to be imported at a large scale to fulfill domestic demands. Hence, the Reliance acquisition of Faradion will play a significant role in fulfilling the need for battery storage in electric vehicles in the coming years.

Other Potential Battery Technologies to Reshape the EV Industry  

Battery manufacturers are investing heavily to develop cheaper, denser, and lighter batteries, giving a twist to the old battery chemistries for significant improvements. The battery technology developed by NAWA Technologies, Ultra Fast Carbon Electrode, is expected to be a game changer in the battery market. The Ultra Fast Carbon Electrode is a vertically-aligned carbon nanotube (VACNT) that can boost battery power ten-fold and increase energy storage by a factor of three while increasing the lifecycle of a battery five times. SVOLT has designed cobalt-free EV batteries, reducing the need for rare earth metals without compromising energy density. The cobalt-free battery could lead to a range of up to 800 km (500 miles) for electric cars. More such developments in the future could lead to better battery options for electric vehicles of the future. 

Way Ahead

The new sodium-ion battery technology still lags behind in energy density compared to the existing battery technologies such as Li-ion and lithium-iron phosphate (or LFP). However, its stability in temperature changes and durability are surely expected to make it lucrative for the electric vehicle industry, especially for light-duty EVs.