Cell Design and Materials: Sodium-Ion

Voltage Range Challenges of Na-ion vs Conventional Chemistries Typical wider voltage ranges of some Na-ion batteries adds complexities where DC-DC converters or inverters operate inefficiently increasing costs and energy losses.

Max V / Min V

NORMALIZED FULL CELL OPERATING VOLTAGE RANGE

What current power electronics are designed for

Conventional Chemistries

Sodium-ion Chemistries

Use-case Examples

Explanation

Data center UPS / Telecom backup

Power conversion requires constant DC voltage. A buck/boost converter needs to be more complex to compensate, reducing efficiency and increases costs.

Grid Connected Storage & BESS

Inverters need a predictable DC link. Wide voltage → inverter either oversized, derated, or added extra DC-DC stage → extra cost.

PV or renewables storage applications

For PVs, the voltage swings mean you can’t extract maximum power efficiently without complex controls. Poor MPPT (maximum power point tracking)

EV traction/motive batteries

Motor controllers are optimized for a narrower voltage range (like Li-ion). Wide voltage → more frequent switching between buck/boost → I2R losses increase.

Battery management complexity

Slopy voltage ranges improve SoC monitoring, but wide ranges require more complex power conversion tools.

Note: A major contributor to Na-ion’s wider voltage range is the hard carbon anode, that has a sloped voltage profile, this does not happen in alloy anodes/anodeless full cells (not yet commercialized however).

Extracted from the PDF; charts and images may read imperfectly.