Lithium (Li)-ion batteries (LIBs) are the electrochemical energy storage systems of
choice for a wide variety of applications, however other types of emerging battery technologies
are currently on the path to share their dominant position.
Among them Sodium (Na)-ion batteries (NIBs) have great potential to represent the next
generation low cost and environmentally friendly energy storage solution.
The diverse key performance indicators required by different applications and the market diversification
is the driving force pushing the Na-ion technology closer to the market.
A team of scientists including WMG at the University of Warwick combined their knowledge
and expertise to assess the current status of the Na-ion technology from materials to
cell development, offering a realistic comparison of the key performance indicators for NBs
and LIBs.
LIBs play a primary role in the transition to a low carbon economy.
However, as the market rapidly expands, the environmental and social challenges associated
with the mass production of LIBs is triggering large attention toward the search for alternative
energy storage solutions based on materials that can be sourced in a sustainable and responsible
way.
In this scenario, NIBs represent an alternative low cost, sustainable and more environmentally
friendly energy storage technology.
In the paper 'Challenges of today for Na-based batteries of the future: from materials to
cell metrics', published on the Journal of Power Sources, a large team of Na-ion technology
expert scientists, led by WMG, at the University of Warwick (UK) analyse the prospect of NIBs
taking a spot in the energy storage market.
Na- based batteries offer a combination of attractive properties.
They are low cost, use sustainable precursors and have secure raw material supplies.
In addition, they are considered as a drop-in technology which could benefit from the already
existing Li-ion batteries manufacturing facilities.
As Li-based systems, Na-based batteries come in different forms, such as Na-ion, Na-all-solid-state-batteries,
Na-O2 and Na/S. While Na-O2 and Na/S are seen as disruptive future technologies, the Na-ion
technology represent an attractive technology almost ready to challenge the Li-ion batteries
in specific applications.
Performance metrics are of utmost importance for the SIB technology to ensure a competitive
cost per Wh and find a place in the market.
In this work, the most promising electrode materials and electrolyte systems have been
reviewed and performance metrics from the academic literature have been used to extrapolate
full sodium ion cells performance indicators.
Authors indicate that with the ongoing development, the present best materials available for Na-ion
cells should allow approaching the energy density of the present generation of Li-ion
commercial cells.
One of the most important application field for the developed sodium-ion battery prototypes
is certainly stationary energy storage systems, where cost and cycle life represent two fundamental
parameters.
In this field sodium-ion batteries have the potential to dominate the future market representing
the most promising system to fill the gap between energy production and utilization
by securing energy supply.
However high-power applications in the electrified automotive field are a potential niche field
application for NIBs.
Further technological improvements are needed to increase the performance especially in
terms of energy density.
Extremely encouraging results have been achieved for the Na-ion technology in a very short
time when compared to the Li-ion technology.
Technological improvement will be achieved by cell component fabrication/assembly optimization,
as occurred in the last thirty years for the LIB technology.