As the prices of lithium rally, sodium-ion batteries (SIBs) have emerged as a promising alternative to traditional lithium-ion batteries (LIBs) in automotive applications. In this article, we explore what SIBs are and how they differ from LIBs.
Lithium-ion Batteries: The Reigning Champion
Lithium-ion batteries have long been hailed as the king of electrochemical batteries, thanks to their lightweight nature and extended life cycle. The primary reason for their widespread adoption in electric vehicles (EVs) is their high energy density.
The ability of lithium-ion batteries to store more energy in less weight/volume makes them ideal for e-mobility applications. However, one drawback is their tendency to heat up quickly, necessitating additional safety measures and costs.
Nevertheless, traditional LIBs are nearing their physico-chemical limit, prompting a renewed interest in exploring alternative cell chemistries that can offer higher density, power, and safety for EVs.
The Advantages of Sodium
SIBs, similar to LIBs, consist of an anode, cathode, separator, and electrolyte. However, instead of lithium, they use sodium as the charge carrier.
Sodium possesses several advantages over lithium, including:
- Safety: SIBs provide enhanced safety compared to LIBs. Sodium exhibits lower chemical reactivity, reducing the chances of thermal runaway or fire hazards commonly associated with lithium-based batteries.
- Environmental Footprint: Lithium extraction can cause significant environmental harm due to extensive mining and chemical processing. In contrast, sodium extraction is more sustainable, mitigating the environmental and social implications associated with mass-market battery production for electric vehicles.
Energy Density Challenge
The primary challenge faced by SIBs is their lower energy density compared to LIBs. This means that a sodium-based battery needs to be larger and heavier to store the same amount of energy as its lithium-based counterpart. Consequently, EVs powered by SIBs have shorter ranges for batteries of the same size.
This limitation directly affects the driving range and overall performance of electric vehicles, making SIBs less ideal for applications that require high power or long endurance.
Nevertheless, sodium has a distinct advantage in terms of its abundant supply. The earth’s crust contains approximately 1,300 times more sodium than lithium, which is already a readily available resource.
The geological abundance of sodium makes it cheaper to extract, potentially resulting in lower production costs. This affordability positions SIBs as an attractive option for electric vehicles, especially when compared to lithium’s supply problems, which have driven up prices significantly.
While lithium prices have been soaring, sodium currently trades at approximately one-tenth the price of lithium, making sodium-ion batteries a much more cost-effective solution in theory.
Sodium-ion batteries have been in development for some time, but it is only recently that major players have started commercializing the technology. Contemporary Amperex Technology Ltd (CATL), a Chinese battery giant, is currently leading the industry in sodium battery production.
Several automakers, including JAC, BYD, and Chery, are planning to launch cars powered by sodium batteries this year, further driving the commercialization of SIBs.
Experts suggest that sodium-ion batteries may find a more favorable market for stationary storage installations, such as those used for backup power in homes, businesses, or the electrical grid. However, market conditions can quickly shift and impact the viability of lithium alternatives.
The future prospects of sodium-ion batteries are closely tied to the cost of lithium. A decline in lithium prices could pose significant challenges for SIBs, as it is challenging to keep up with the ever-improving lithium-ion batteries that are becoming increasingly affordable.
Jay Whitacre, a battery researcher at Carnegie Mellon University, and former founder of Aquion, a sodium-ion battery company, states, “It’s hard enough to develop new batteries and manufacture them at scale. It’s even more challenging to compete with the ever-improving lithium-ion batteries that are constantly getting cheaper.”
In conclusion, sodium-ion batteries offer a promising alternative to lithium-ion batteries, particularly in light of the rising prices of lithium. While SIBs face challenges related to energy density, their advantages in terms of safety, environmental sustainability, and lower production costs make them an attractive option for the future of electric vehicles and stationary energy storage.