The energy storage industry has long been dominated by lithium-ion batteries, but recent developments have shown that this trend may be reaching a bottleneck. One such technology that has caught the attention of many is sodium-ion batteries (SIB). Sodium is an element with similar physiochemical properties to lithium but has unique advantages, such as natural abundance, environmental friendliness, and lower cost. In the coming years, it is expected that sodium-ion batteries will play an increasingly prominent role in the energy storage landscape. Carbon-based materials such as hard carbons, carbon nanotubes, and graphene have been investigated for their potential use in sodium-ion batteries.
The downfall of lithium-ion batteries
Almost every electric car contains a lithium-ion battery. Lithium is mined mainly in Argentina, Chile, Australia and China with the latter accounting for 60% of the world’s lithium supply. The International Energy Agency (IEA) predicts that the number of electric vehicles on the road will skyrocket from 6.6 million in 2021 to 200 million by 2030. The booming EV industry has led to a surging demand for lithium, a critical mineral, which extraction needs to increase 26 times between today and 2050 to meet the global demand. This has contributed to a price increase in battery-grade lithium of 569% since 2021. The increased cost and scarcity of the material are not the only challenges that electric car manufacturers must overcome. Lithium mining harms the soil and causes air and water pollution, putting at risk the local population and biodiversity. For every ton of lithium, 15 tons of CO2 is emitted into the atmosphere.
Are sodium-ion batteries (SIB) here to stay?
Sodium-ion batteries have gained great interest and can eventually replace lithium-ion batteries once new technologies are developed to optimise their performance. Sodium can be found in large quantities that exceed lithium natural resources over 500 times. Its infinite nature makes it a sustainable material to source at a relatively low cost, thus ideal for mass production. Obtaining sodium and other raw materials for Na-ion batteries is not only more environmentally sustainable but also more ethical than mining lithium and cobalt which has been linked to alleged right abuses.
Furthermore, sodium-ion batteries are safer compared to lithium-ion ones which are flammable and sensitive to temperature changes. Cold temperatures below 0 are proven to cause capacity loss, whereas hot temperatures can increase the hazards of explosions and fire.
Next-gen sodium-ion batteries enhanced with carbon materials
When it comes to SIB anodes graphite is not suitable material as in LIB anodes. However, hard carbon due to its unique properties is an attractive component for the SIB anode that can result in high energy density and long cyclability. A distinguishing characteristic of hard carbon is its structure which allows a lot of flexibility in design, enabling precise control of how the battery functions, including how long it lasts, and how quickly it can be charged.
Carbon nanotubes have been used as both anode and cathode materials in sodium-ion batteries, and they have shown promise in improving their electrochemical performance. UP Catalyst, a leading supplier of sustainable carbon materials out of CO2, collaborated with Imperial College London to validate their products in Na-ion batteries. The tests conducted by the Titirici group with UP Catalyst’s carbon nanotubes indicated that the cyclability of the batteries increased significantly. The results showed 93.75% capacity retention after exceeding 4000 charge and discharge cycles. By contrast, the batteries that are currently in widespread use become depleted after just 800 cycles while experiencing a significant reduction in capacity. UP Catalyst’s electrode material also exhibits excellent stability and improved energy density, making it a promising candidate for large-scale energy storage applications.
Key players in the future battery playground
As battery giants like Contemporary Amperex Technology Co., Limited have claimed to have solved the sodium-ion batteries’ energy density problem, the only downfall compared to Li-ion batteries, there is nothing stopping large manufacturers from turning towards mass production of new generation sodium-ion batteries. HiNa Battery Technology Co., Ltd. in China, Tiamat Energy in France, ALTRIS in Sweden, and Natron Energy in the US are all commercializing sodium-ion batteries indicating a huge shift in energy storage technologies. UP Catalyst has now come up with a sustainable electrode material for the battery composition that increases the battery characteristics even further.
The future battery landscape is facing interesting times. Are sodium-ion batteries really catching up or does performance outweigh the cost and Li-ion cannot be budged from the throne?