Sodium-ion rechargeable batteries could soon be an inexpensive and resource-saving alternative to the present lithium-ion ones. High-End prototypes and ingeniousdiscoveries in basic research have made a breakthrough seem forthcoming in the foreseeable future.Sodium-ion battery manufacturing enables a country to take ownership of its energy security the energy supply chain, at low cost and low risk, says James Quinn CEO of Faradion.
|| Sajeeda Feroz
Since the last 4000 years, after the invention of the wheel, human transport has hardly evolved. The advent of the internal combustion engine (ICE) has substantially changed the way we travel today. Despite regular micro-inventions, the fundamentals of ICE and its reliance on lead acid batteries has remained unchanged from the 1890s until today. In the 1970s, there arose a competition to invent more sustainable batteries and a decade of innovation lead to the birth of the first commercially viable lithium-ion batteryin 1985.Lithium-ion batteries revolutionised our lives since they first entered the market in 1991.
Although electric vehicles and electric modes of transport are the new rage today, their limited range, high prices, a cumbersome charging infrastructure and resource-intensive battery production have delayed a rapid turnaround. For electric vehicles to come into more widespread use, batteries must become even more powerful, durable, sustainable and cost-effective.
Electro-mobility, combined with renewable electricity production, is widely regarded aclimate-friendly model for the future. However,lithium-ion batteries are still expensive and have major sustainability issues. Use of lithium in rechargeable batteries has slowed down the large-scale electrification of vehicles across the world.
The advantage of lithium-ion batteries isthat,lithium ions flowback and forth between the anode and cathode and are not based upon chemical reactions that break down the electrodes. These batteries are exclusively reliant on finite metals that are difficult to extract from the earth’s crust. Even under highly optimistic production assumptions, there will be insufficient supply in the medium term.
China controls most of the world’s cell battery material supply chain,representing more than 80 per cent of battery costs. With more than 75 per cent of world’s lithium-ion manufacturing capacity, its lithium reserves are 30 times greater than those of the US. 72 per cent of the world’s reserves of cobalt are in Democratic Republic of Congowhich is largely owned by China.
As the world seeks to distance itself from its over-dependence on China (particularly noteworthy in recent policy shifts from the US and India), lithium-ion batteries will never be the answer for a cleaner, more sustainable environment for future generations.
Sodium to replace lithium
The solution could be sodium-ion batteries, whose development has recently made astonishing progress and they could replace the lithium-ion batteries currently used not only in electric vehicles, but also in smartphones and laptops in the foreseeable future. Although sodium does not have the energy density of the comparatively rare lithium, it is cheaply available.
Some reasons why Sodium is a better choice comparing Lithium:
- It is proven that the sodium-ionmatches lead-acid cost of ownership, with performance as good as lithium-ion or more as they are chemically similar.
- A country can invest in its own supply chain, moving away from Chinese dependency.
- Sodium is the sixth most abundant element in the earth’s crust, so there is no scarcity.
- Sodium-ion batteries are safer as they can be discharged to 0 V (zero energy) unlike lithium- ion batteries.
- Availability of cheaper precursor materials, benefitting from cobalt-free cell chemistry, with no need for graphite, copper or lithium either.
- Does not consume any scarcely available raw materials.Powerful anodes can be produced from lignite, wood and other biomass. Cathodes can be produced from simple table salt.
However, the current performance of sodium-ion batteries lags behind that of lithium-ion batteries by about 20 years. For decades, research has been concentrated solely on the more powerful lithium. Although recently, there have not only emerged groundbreaking scientific publications, but also very promising prototypes.
Research into sodium-ion batteries has been going on since the eighties in an attempt to find a cheaper alternative to lithium.
By using salt, the sixth most common element on the planet, batteries can be made much cheaper. Commercialising the batteries is expected to begin for smartphones, cars and more in the next five to 10 years.
A South Korean sodium-ion battery managed to handle about 500 complete charging cycles before its capacity dropped to 80%. A battery with a slightly different chemical structure devised by a US-Chinese research group achieved 450 charge cycles with a similar charging capacity and a Chinese sodium-ion battery had a slightly lower capacity, but still retained 70% of its capacity after 1,200 cycles of quick 12-minute charging.
This doesn’t sound like muchon paper,but in reality, these batteries could survive many more charge cycles, because in everyday life batteries tend to be only partially charged and discharged.The complete loading and unloading of a battery in an experiment strains the cell.
However, sodium has two disadvantages. For one, it is three times heavier than lithium, therefore sodium-ion batteries are also heavier. Comparatively lithium accounts for less than 5% of the total weight of a battery. In addition, sodium batteries are less powerful because they inevitably lose around 10% of their energy density due to a 0.3-volt lower cell voltage. This is owing to the fact that the graphite anodes that have been used until now absorb too little sodium.
Fortunately, sodium-ion batteries are no longer just a theoretical concept. A breakthrough seems imminent that will soon see them become practical reality. The latest research results show that there are already tangible, affordable and resource-saving alternatives to the expensive lithium-ion batteries and that their performance can possibly be significantly increased by multilayer storage.
It will certainly take some time before sodium-ion batteries reach a stage of technical maturity and can be produced in large quantities to satisfy the needs of electric vehicles and when that does happen, the transition from lithium- to sodium-ion batteries will be largely feasibleowing to the fairly similar technology involved.
Long story short, manufacturingsodium-ion batteries enables a country to take ownership of its energy security and the energy supply chain with minimised costs and risks. Economies will soon be faced with a choice of technologies to enhance their needs for sustainability. The winner of this race will be determined not just by the price and efficacy, but also by supply chain security considerations.