With the world shifting towards renewable energy, the method of storing such energy effectively and at a reasonable cost is gaining significance. Although the lithium-ion battery has served as a primary battery over the past years, the sodium-ion battery is emerging as an environmentally friendly alternative with reduced costs.

Their cost-effectiveness and sustainability make them attractive for renewable energy storage, electric vehicles, and off-grid power systems. This post will share how a sodium-ion battery works, its key components, advantages, limitations, applications, future potential, and practical alternatives.

What Is a Sodium-Ion Battery?
A sodium-ion battery, SIB, or Na-ion battery is a rechargeable device. Energy is stored in the battery through shuffling sodium ions back and forth between two sections known as the cathode and anode. It functions pretty much the same as a lithium-ion battery (LIB). However, it contains the sodium element rather than lithium to move the charge. The role of a sodium-ion battery is as follows:

Discharging: Sodium ions move back and forward between the anode and the cathode via the electrolyte. This causes current flow through a circuit to provide electricity.
Charging: This pushes back the sodium ions to the anode, and the external power source stores electricity.

What Differs a Sodium-Ion Battery From a Lithium-Ion One?

Sodium-ion and lithium-ion are not merely a case of exchanging one metal with another. Their differences are found in operation, cost, and application, among other features. Here's a detailed comparison of both batteries:

1.Charge Carrier: SIB batteries charge transfer with the help of sodium ions, and LIB batteries charge transfer with the help of lithium ions.

2.Availability and Cost of Material: Sodium is abundant and cheap due to an abundant source supply, such as salt, whereas lithium is rarer and concentrated in certain parts.

3.Ion Size & Mobility: Sodium ions are larger and move slower reducing the density of energy. Unlike lithium ions, which are smaller and have the ability to travel and accommodate energy more readily in an equal space.

4.Voltage Operating: Sodium-ion batteries use approximately 3.0 V, whereas lithium batteries use approximately 3.7 V, which provides more energy output.

5.Electrode Materials: SIBs utilize materials such as layered oxides, Prussian Blue Analogs, and polyanionic compounds. Conversely, LIBs make use of layered oxides, spinel, and phosphates. Sodium batteries employ hard carbon or alloy-based anodes, as opposed to lithium batteries that mostly employ graphite or silicon.

6.Electrolytes: All batteries are powered by an organic solvent. The distinction is that SIBs use sodium salts, whereas in LIBs, there's the use of lithium salts.

7.Energy Density: Dense batteries like SIBs have a lower energy density of 100-200 Wh/kg. Instead, LIBs contain far higher energy density (200-260 Wh/kg) and thus are more appropriately used in small gadgets and by electrically powered vehicles.

8.Safety and Thermal Stability: The temperature of SIBs is much less susceptible to overheating when compared to an LIB that needs more critical handling.

9.Cost & Supply Chain: A Na-ion battery is cheaper as it does not use costly metals such as cobalt and nickel like the lithium one.

10.Applications: SIBs can be used for grid storage and low-demand vehicles. But when it comes to high-performance electric cars or even appliances, then it's lithium where it's at.

Crucial Components of a Sodium-Ion Battery
There are four components of sodium-ion batteries, among which every part defines the performance, safety, and efficiency of the battery: