At Celltech, our unwavering commitment to pushing the boundaries of battery technology drives us to explore emerging technologies continually. We recently conducted a comprehensive series of tests on sodium-ion cells to evaluate their readiness for integration into our battery solutions. In this article, we provide an insightful overview of sodium-ion batteries and discuss the intriguing test results that could shape the future of battery solutions.
Sodium-Ion Battery Overview
Sodium-ion batteries have emerged as a compelling alternative to conventional lithium-ion batteries, primarily due to their potential to address some of the fundamental limitations associated with lithium.
One of the most striking advantages of sodium-ion batteries lies in the abundance of sodium, a resource readily obtained from saltwater. This natural abundance mitigates concerns related to the uneven geographic distribution and cost of materials required for lithium-ion batteries. The quantity of sodium resources is about two hundred times higher than that of lithium. Also, the price of salt is expected to remain significantly lower than that of lithium carbonate.
It’s worth mentioning that sodium-ion batteries have been around for quite some time. To be precise, initial studies started in the 1970s, which is roughly the same period when lithium-ion batteries were also under development.
The reason why lithium-ion batteries became the norm instead of sodium lies within certain challenges sodium-ion has had. Initially, there was not a suitable anode for this chemistry. This has since been solved. In addition, sodium-ion batteries have lower energy density compared to their lithium-ion counterparts. Resolving these challenges is pivotal to ensuring sodium-ion batteries function effectively across diverse applications.
Battery Chemistry Comparison: Sodium-ion vs. Other Chemistries
The structure of sodium-ion battery cells is similar to that of lithium-ion cells, with the exception of a hard carbon anode instead of graphite. While the cathode materials may also vary slightly, the electrolyte and separator materials are the same as those found in lithium cells.
Today, sodium-ion batteries offer competitive energy density, although they still fall slightly short compared to some other chemistries. However, they excel in charge-discharge cycles, especially compared to lithium cobalt oxide and lead-acid batteries. They also perform well in cold and high-temperature environments, a significant advantage over other viable chemistries. They are versatile in their rate capacities, just like LCO.
Sodium-ion batteries are eco-friendly, unlike lead-acid batteries. They also have immense potential for further development with scalability and performance enhancement.
In summary, sodium-ion batteries provide a compelling alternative to conventional lithium-ion batteries, with notable advantages in resource availability, low-to-high-temperature performance, and the number of lifecycles. While they may not outperform lithium-ion batteries in every aspect, sodium-ion technology shows immense promise.
Sodium-Ion batteries can be utilised in various applications, such as telecom base stations, low-speed electric vehicles, e-bikes, small work machinery, household energy storage, grid energy storage, and electric vehicles.
Testing Sodium Cells
At Celltech, we conducted extensive testing to assess the performance and characteristics of sodium cells. We tested cells from multiple suppliers.
The testing process involved a thorough evaluation of critical parameters such as capacity, size, and overall performance, all measured against strict standards. Through this rigorous testing process, we confidently identified the strengths and weaknesses of different alternatives.
Test Results of Sodium Cells
Our initial tests unveiled a spectrum of findings, some of which raised important questions about the long-term performance of sodium cells.
Cells from some suppliers exhibited sudden drops in capacity, prompting concerns about their reliability. In the case of other suppliers, while capacity levels were adequate, the need for more consistency in performance became evident. Consistency is an indispensable factor in battery performance, ensuring uniformity and predictability across the cells in a battery. The observed inconsistencies among these sodium cells cast doubt on their suitability for high-quality applications.
However, amidst these challenges, we identified one exceptional sodium-ion cell. This supplier was a clear standout performer. So far, our tests have been running for over five hundred cycles and are still ongoing. The target is to run the test for two thousand cycles. So far, this particular cell has demonstrated good performance and consistency in our tests. It holds tremendous promise for specific applications, and we will further investigate the possibility of offering it for customer battery pack projects.
In conclusion, our journey into sodium-ion batteries has illuminated the potential and challenges inherent to this promising technology. As we continue our relentless pursuit of innovation at Celltech, we remain committed to pushing the boundaries of battery technology. We aim to deliver cutting-edge, reliable, sustainable battery solutions for a rapidly evolving world. We will continue working towards harnessing sodium-ion batteries’ power in our battery solutions. Do not hesitate to get in touch should you be interested to learn if sodium-ion technology would suit your customised battery needs.