Lithium-ion batteries power so many key areas of our lives today. From the smartphones we communicate to the EVs we drive, we can thank lithium-ion technology for powering us.
But a new battery technology – sodium-ion – is currently emerging as a potential alternative for many applications.
As it’s a new technology, there are lots of questions about the benefits and ideal use cases for sodium-ion batteries. Equally, many people are unsure whether they’re a viable alternative for sodium-ion solutions.
In this blog post, we provide the answers, and explain the main differences between sodium-ion and lithium-ion batteries, to help you understand when each technology could be used efficiently and effectively.
Lithium vs Sodium
The main difference is the material used to move the charge through the battery. Lithium-ion batteries use lithium ions, while sodium batteries use sodium ions.
Both technologies operate similarly, as we explained in our recent blog post introducing you to sodium ion technology.
What has gotten many people excited about sodium-ion tech, is that sodium is much more abundant than lithium, as it’s readily available from salt. In contrast, lithium is more geographically concentrated.
This wider availability doesn’t necessarily make sodium cheaper than lithium, but it does reduce global dependence on constrained raw materials.
Energy Density & Size
One of the main benefits of lithium-ion batteries over sodium-ion is energy density. This refers to how much energy a battery can store relative to its weight or size.
Higher density batteries let manufacturers build batteries that provide more power without significantly increasing their weight or size. Lithium excels in this area, which is why it is the go-to for applications like phones, computers, and EVs, where size and weight really matter.
Sodium-ion batteries tend to have lower density. So, for the same amount of stored energy, a sodium-ion battery may need to be larger or heavier than its lithium counterpart.
Cost & Raw Materials
From a cost standpoint, sodium-ion batteries are likely to be competitive. Currently, lithium-ion production depends on several crucial raw materials, including lithium, nickel, cobalt, and others. The prices and availability of these materials can hike the price of the finished product.
Sodium-ion batteries avoid lithium entirely and can be designed around different combinations of electrode materials. This may make them cheaper than lithium alternatives, particularly in the medium to long term, when sodium manufacturing has received more investment.
Still, in the shorter term, don’t assume that every sodium battery will be cheaper than a lithium one – this simply won’t be the case as the technology develops and matures.
Safety & Temperature Performance
When properly designed and managed, lithium-ion batteries are generally safe. But under certain conditions, damaged or poorly controlled lithium batteries can experience thermal runaway. There’s also a heightened fire risk with some lithium ion battery applications.
Sodium ion batteries, in contrast, have higher thermal stability and carry lower fire risks. Again, while we can’t say that every sodium-ion battery will be safer than a lithium alternative, its increased stability makes it a viable option where temperatures are variable.
This is backed up by the fact that sodium-ion is known to perform well at low temperatures as well as high.
Lithium vs Sodium ion: Where Each Technology Makes Sense
Lithium-ion batteries are particularly well suited to applications where energy density is critical. This includes electric cars, electric bikes, smartphones, laptops and other portable electronics.
These products benefit enormously from having a battery that can store a large amount of energy without adding excessive weight or volume.
Sodium-ion batteries are more interesting in applications where size and weight are less important.
One of the biggest opportunities is stationary energy storage. As electricity grids incorporate more solar and wind generation, large battery systems are increasingly being used to store electricity and balance supply and demand.
For grid storage, the physical weight of the battery is usually far less important than its cost, reliability, safety and lifespan. A larger battery can be perfectly acceptable if it provides electricity storage at a competitive price.
Other potential applications include telecommunications backup systems, data centres, warehouse equipment, forklifts, robotics, low-speed electric vehicles and refrigerated logistics.
Cold environments may also provide an interesting niche for sodium-ion technology because of its potential low-temperature performance.
The Bottom Line: Which Are Better – Sodium or Lithium ion Batteries?
It’s not really a case of which battery is better, as they’re both useful and highly efficient for different applications.
That said, lithium-ion currently has the advantage in energy density, manufacturing scale, market maturity and proven performance. For applications where space and weight are critical, it is likely to remain the preferred technology for many years.
Sodium-ion, meanwhile, offers a different set of strengths. Its reliance on abundant sodium, potential cost advantages, safety characteristics and suitability for stationary storage make it an increasingly interesting alternative.
Keen to Learn More?
Explore our range of sodium-ion batteries or get in touch with one of our experts for more information about our latest technology.
You can also keep up to date with our latest sodium-ion projects in Africa, where we’re leading the way as one of the first to develop and roll out the technology on the continent.
