Cell Design and Materials

Impact of Form Factor on Performance Form Factor

Volumetric Energy (Wh/L)

Gravimetric Energy (Wh/kg)

Other Key Trade-Offs

Pouch Cells

Highest; Lightweight, flexible thinnest casing and efficient active material packing allows highest Volumetric Energy Density.

Highest; No metal can adding weight allows maximum Gravimetric Energy Density

Fragility (leaking, off-gassing); Requies Thermal & Mechanical Management on pack level, no Safety Devices, typically slower stacking manufacturing speed

Prismatic Cells

High; though slightly lower than pouch due to rigid casing and internal clearances.

Medium: Rigid metal casing adds weight relative to pouch, but less than cylindrical on a per-cell basis.

Thermal non-uniformity, Susceptible to swelling, higher cost, Excellent packing efficiency in battery packs, better safety than pouch. Depending on stack vs wind lowest $/kWh

Cylindrical Cells

Lowest; Round shape leaves gaps when packed

Lowest; heavy and rigid Steel or Aluminum casing adds significant weight

Round geometry limits packing efficiency, Best thermal uniformity, mechanical robustness. fastest winding speed for manufacturing. Also lowest $/kWh. Better safety then Pouch

Overall Form Factor selection is highly contingent on application and needs of the applications or consumer. Novel chemistries favor pouch due to its relative ease of new material integration and Wh/kg & Wh/L advantages Source: Battery Report 2023 and 2024, Battery Talk: Battery Application Break Down 12/31/2025 Version 3.0)

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