Why in News
India’s accelerated push toward electric mobility and renewable energy storage has deepened its reliance on lithium-ion batteries. However, concerns over critical mineral dependence, high import exposure, and geopolitical vulnerabilities have renewed policy attention on alternative battery technologies. In this context, sodium-ion batteries are gaining prominence as a strategic option to enhance India’s long-term energy security and industrial resilience.
Batteries as the Foundation of Modern Energy Systems
Batteries have become indispensable across sectors, powering consumer electronics, electric vehicles, grid-scale storage systems, and household appliances. As energy systems transition toward renewable sources, batteries are no longer peripheral technologies but core infrastructure, central to economic competitiveness, energy security, and decarbonisation objectives.
Lithium-Ion Batteries: Market Leadership with Structural Limits
Lithium-ion batteries dominate global markets due to their:
- High energy density
- Long operational life
- Low self-discharge rates
Sustained investments over several decades have enabled large-scale manufacturing and steep cost reductions, with prices declining from nearly USD 1,100 per kWh in the early 2010s to about USD 108 per kWh by 2025.
Despite these advantages, lithium-ion technology is constrained by structural vulnerabilities:
- Heavy reliance on critical minerals such as lithium, cobalt, nickel, and graphite
- Geographic concentration of mineral reserves and refining capacity
- Exposure to supply disruptions, price volatility, and geopolitical tensions
As global demand rises, these risks are expected to intensify.
Lithium-Ion Battery: Basic Structure
A lithium-ion battery comprises:
- Anode (negative electrode): Typically graphite
- Cathode (positive electrode): Commonly lithium metal oxides such as Lithium Cobalt Oxide (LiCoO₂), Lithium Manganese Oxide (LiMn₂O₄), or Lithium Iron Phosphate (LiFePO₄)
- Electrolyte: A lithium salt dissolved in a solvent enabling ion movement
- Separator: A porous membrane preventing short circuits while allowing ion flow
- Current collectors: Separate positive and negative collectors
During discharge, lithium ions move from the anode to the cathode; during charging, the process reverses. These batteries are rechargeable and can undergo hundreds to thousands of cycles depending on chemistry and usage conditions.
India’s Battery Manufacturing Aspirations and Constraints
India has attempted to develop domestic battery manufacturing capacity through initiatives such as the Production Linked Incentive (PLI) scheme for Advanced Chemistry Cells (2021), under which nearly 40 GWh of capacity has been allocated. However, actual commissioning remains limited to around 1 GWh.
Key constraints include:
- Limited and largely unproven domestic lithium reserves
- Weak downstream ecosystems for processing, cathode-anode production, and separators
- Continued import dependence for lithium-ion cells and components
These challenges highlight the necessity of parallel investments in alternative battery chemistries.
Sodium-Ion Batteries: Performance Assessment
Sodium-ion batteries have lower specific energy than lithium-ion batteries due to sodium’s higher atomic mass. However, the performance gap is often overstated.
- Layered oxide sodium-ion chemistries already outperform polyanionic and Prussian blue variants
- Energy densities are approaching those of lithium iron phosphate (LFP) batteries
- Ongoing material innovation and cell-level optimisation are expected to further narrow the gap
- Laboratory and pilot-scale studies indicate substantial long-term improvement potential
Safety Advantages of Sodium-Ion Technology
Safety represents a major comparative advantage of sodium-ion batteries:
- Lower temperature rise during thermal runaway events
- Not classified as “Dangerous Goods” for transportation
By contrast, lithium-ion batteries require:
- Transport at ≤30% state of charge
- Strict handling protocols due to copper current collectors and short-circuit risks
Sodium-ion batteries:
- Use aluminium current collectors on both electrodes
- Can be safely stored and transported at zero voltage
- Significantly reduce logistics costs and operational risks
Manufacturing Compatibility and Material Security
From an industrial perspective, sodium-ion batteries offer notable advantages:
- Compatibility with existing lithium-ion manufacturing lines with minimal modifications
- Lower capital investment requirements
- Reduced exposure to fragile critical mineral supply chains
Material security benefits include:
- Sodium sourced from abundant resources such as soda ash
- Elimination of several critical minerals
- Replacement of copper with aluminium, lowering costs and weight
These features enhance supply-chain resilience and strategic autonomy.
Strategic Relevance of Sodium-Ion Batteries for India
Globally, approximately 70 GWh of sodium-ion battery manufacturing capacity is expected to be operational by 2025, with projections of nearly 400 GWh by 2030. Costs are anticipated to undercut lithium-ion batteries by 2035.
For India, sodium-ion technology can:
- Reduce dependence on imported critical minerals
- Improve safety and logistics efficiency
- Strengthen national energy security
- Support long-term clean energy and decarbonisation goals
Policy and Ecosystem Measures
To accelerate adoption of sodium-ion batteries, India should:
- Extend upstream manufacturing incentives to include sodium-ion chemistries
- Design future PLI schemes to support multi-chemistry flexibility
- Update standards, safety codes, and certification frameworks
- Encourage EV manufacturers to approve sodium-ion battery platforms
- Promote R&D, pilot projects, and early deployment in grid storage, two- and three-wheeler EVs, and stationary energy systems
Conclusion
India’s energy transition demands not only scale but resilience. While lithium-ion batteries will remain important, their material and geopolitical constraints necessitate diversification. Sodium-ion batteries present a safer, resource-secure, and manufacturing-compatible alternative. Through coordinated industrial policy, regulatory reform, and market incentives, India can develop a future-ready battery ecosystem in which sodium-ion technology enhances energy security and strategic autonomy.