Chinese battery manufacturer Cornex New Energy has announced a new lineup of sodium-ion battery cells, including fresh prismatic formats aimed at the stationary energy storage market.

For energy storage applications, the company's portfolio now includes 165 Ah and 58 Ah models. The 165 Ah cell was spotlighted for its cathode material, sodium iron pyrophosphate, paired with a hard carbon anode (polyanion-type NFPP + hard carbon). Designated the PN173-165A, the cell has already secured key certifications, including China’s GB standard, UN38.3, UL, and IEC 62619.

Cornex is positioning the cell as "ideal for frequency regulation" due to its exceptionally long cycle life. The company reports a 1P energy efficiency of ≥94.5% and a lifespan exceeding 20,000 cycles. The unit weighs 4.5 kg and measures 71.7 by 174.4 by 207.2 mm.

When asked for further specifications, Cornex indicated that the nominal gravimetric energy density stands at 102 Wh/kg (0.5P), with a nominal volumetric energy density of 182 Wh/L (0.5P).

For context, a comparison with Cornex’s own LFP offering shows that its 314 Ah cell weighs 5.6 kg—about 24% heavier but delivering 90% more energy. This disparity helps illustrate some of the current density limitations associated with sodium-ion technology.

Nevertheless, sodium-ion cells typically offer advantages in material sustainability and availability, broader operating temperature ranges before performance derating, and enhanced safety relative to lithium-based cells, including higher thresholds for thermal runaway initiation. At commercial scale, the ability to transport sodium-ion cells at zero volts may also significantly reduce logistical risks.

588 Ah Cell Enters Mass Production

Cornex initially revealed its 588 Ah cell back in September 2025 and confirmed within the past week that the model is now "officially moving to mass production."

The 588 Ah cell introduces a suite of design improvements and delivers a gravimetric energy density of 190 Wh/kg, a volumetric energy density of 419 Wh/L, and a round-trip energy efficiency of 96.5%. It is rated for more than 12,000 charge-discharge cycles.

Cylindrical Sodium-Ion Cells for Mobility

The company also announced the market introduction of four cylindrical sodium-ion battery products intended for portable power and mobility uses, such as small e-bikes, scooters, or power tools. These cells are also designed to address persistent challenges in the lower-spec power sector, including poor low-temperature startup performance and severe range loss in cold conditions. The new offerings come in capacities of 10 Ah, 12.5 Ah, 16 Ah, and 26.5 Ah.

In sub-freezing temperatures, standard lithium-ion batteries often cannot be operated safely or suffer significant degradation. While manufacturers can integrate heating elements to maintain optimal temperatures, this approach consumes stored energy and can substantially reduce overall system efficiency.

Deployment numbers are gradually climbing. At the grid-scale level, Peak recently commissioned the largest grid-scale sodium-ion storage system in the United States—though still modest at 3.5 MWh—while significantly larger projects are already operational in China.

On a smaller scale, Bluetti has already incorporated sodium-ion cells into one of its portable products, the Pioneer Na, aiming to deliver a more adaptable portable power station capable of reliable operation in extreme cold weather.