What Is a 26650 Cell — and Why Does the Size Matter?

26mm by 65mm — the 26650 format sits between the familiar 18650 and large prismatic cells. Here is why that matters for industrial packs.

More energy per cell, simpler packs

A 26650 holds roughly 2.5–4Ah, nearly double an 18650, so a pack needs fewer cells and fewer welds for the same capacity — improving reliability and assembly cost.

Thermal mass and pulse power

The larger format also carries more thermal mass and lower internal resistance, which is why PLB’s 25B can deliver 50C pulses while staying within temperature limits.