# item.guide
Side-by-Side Comparison Battery Chemistries

Sodium-Ion (Na-Ion) vs. Zinc-Air

Comparing 2 standards across 9 specifications. 9 key differences identified.

Comparing:
Sodium-Ion (Na-Ion)
Zinc-Air

Sodium-Ion (Na-Ion) chemistry replaces lithium with abundant, low-cost sodium compounds. Operating at 3.0V–3.1V nominal with energy densities of 140–160 Wh/kg, Na-ion cells deliver exceptional low-temperature capacity retention (>85% at -20°C, operable down to -40°C), zero thermal runaway risk at 0V discharge, and use aluminum current collectors on both cathode and anode.

View full Sodium-Ion (Na-Ion) spec sheet →

Zinc-Air is an open-cathode primary battery chemistry that utilizes atmospheric oxygen as the active cathode material. Because the cathode reactant does not need to be stored inside the cell, Zinc-Air achieves exceptional gravimetric energy densities of 400–500 Wh/kg and volumetric densities up to 1,400 Wh/L, making it the universal standard for hearing aids.

View full Zinc-Air spec sheet →

Specification Comparison Table

9 Parameters
Parameter / Spec
Nominal Cell Voltage
3.00 – 3.10 V 1.40 – 1.45 V
Gravimetric Energy Density
130 – 165 Wh/kg 400 – 500 Wh/kg
Volumetric Energy Density
260 – 340 Wh/L 1,100 – 1,400 Wh/L
Cycle Life (to 80% Capacity)
2,000 – 4,000 Cycles Single Use (Activated upon seal removal)
Thermal Runaway Threshold
> 260 °C > 200 (Safe) °C
Operating Temperature Range
-40 to +60 °C 0 to +50 °C
Self-Discharge Rate
2 – 3% / Month < 2% / Year (Sealed) | Drains in 2–4 Weeks (Unsealed)
Primary Anode Material
Hard Carbon (Biomass-derived Non-graphitizable Carbon) High-purity Zinc Powder (Zn)
Primary Cathode Material
Prussian White Analogues / Layered Transition Metal Oxides (NaMO2) Atmospheric Oxygen (O2) via Gas Diffusion Membrane