What Is Slowing the Mass Adoption of Sodium-Ion Batteries? IRENA Explains

A latest report by the International Renewable Energy Agency (IRENA) showed a trend indicating that sodium-ion batteries (SIBs), which share a similar construction to lithium-ion batteries (LIBs), could become a potential alternative. Despite being a less mature technology, sodium is gaining importance because of its availability in a market facing supply chain disruptions arising from geopolitical tensions.

The report highlights the growing importance of SIBs, which are increasingly positioned to play a complementary role to LIBs—or potentially emerge as a disruptive alternative—due to sodium’s high abundance. This abundance enhances security against geopolitical risks, helps support lower costs and makes SIBs a promising option compared with LIBs.

Although alternative chemistries are gaining attention, LIBs continue to dominate the market because of their long lifespan, high energy density and ability to deliver energy quickly. However, IRENA’s Sodium-Ion Battery Technology Brief raised concerns over recent supply chain disruptions. Since 2021–2022, geopolitical tensions have increased worries about the resilience and affordability of LIB supply chains, driving interest in alternatives such as SIBs.

Key Offerings of Sodium-Ion Batteries

IRENA contrasts SIBs with LIBs by noting that SIBs rely on abundant sodium compounds derived from widely available raw materials such as soda ash, unlike lithium-dependent LIBs. This abundance suggests SIBs could ease supply chain pressures and diversify the battery market.

SIBs also share similarities with LIBs in construction but use sodium-based electrolytes. Their cathode materials are categorized into layered oxides, polyanions and framework materials, while anodes are typically carbonaceous materials, transition metal oxides, or intermetallic and organic compounds.

The report cites CATL’s April 2025 announcement of its production-ready Naxtra range of low- and high-voltage SIBs for EVs, which offer an energy density of 175 Wh/kg and could enable up to 500 km of driving range per charge. It also notes that soda ash can be produced synthetically from salt and limestone—both virtually unlimited resources—creating worldwide production potential, despite higher economic and environmental costs than natural soda ash. Lithium resources, by contrast, are more geographically concentrated.

Lower Energy Density but Competitive Costs

While SIBs currently have lower energy density than some high-end LIBs, commercial SIB cells reaching up to 175 Wh/kg are comparable to lower-end LIBs and significantly outperform lead-acid and nickel-based technologies. IRENA further highlights that SIBs have a cost advantage because sodium is far cheaper and globally accessible, reducing supply chain risks and price volatility. Their early-stage development also provides greater room for cost reductions compared with LIBs.

SIBs in EVs and Replacing Lead-Acid Batteries

SIBs are also emerging as an option for EVs—especially short-range models—given their current gravimetric energy density of up to 160 Wh/kg, fast-charging capability, wide operating temperature range and strong safety profile. In 2024, China, India and Southeast Asia accounted for roughly 80% of global two- and three-wheeler sales, and industry announcements point to rising interest in SIB adoption for these vehicle categories.

Another potential application is retrofitting, where SIBs could replace lead-acid batteries in conventional road vehicles or in electric two- and three-wheelers. SIBs could potentially triple energy density and outperform lead-acid batteries in cycle life, low-temperature performance, safety, sustainability and fast charging, according to the report. SIBs are also being explored for other uses, including high-power cells for small devices and power tools.

Current Challenges

Despite strong potential, SIBs are not seen as a complete substitute for LIBs but rather as a complementary technology addressing sustainability and supply concerns. Their long-term success depends on factors such as cost and material availability. Lithium supply chain bottlenecks, shortages or rising prices could boost SIB adoption, while further LIB cost reductions may suppress demand for SIBs.