21700 vs. 9V Battery
Comparing 2 standards across 7 specifications. 7 key differences identified.
A 21700 Li-ion cell measures 21.1mm in diameter and 70.4mm in length. Offering 4000 to 5000 mAh capacity at 3.6V nominal, it provides up to 50% more energy density than an 18650 cell.
A 9V battery (IEC designation 6LR61, commonly called PP3) is a rectangular battery measuring approximately 48.5mm x 26.5mm x 17.5mm with two snap terminals. Alkaline 9V cells output 9.0V nominal from six internal 1.5V cells in series, with typical capacity around 400-600 mAh.
Specification Comparison Table
7 Parameters| Parameter / Spec | ||
|---|---|---|
|
Diameter
|
21.10 mm | — |
|
Overall Length
|
70.40 mm | — |
|
Nominal Capacity
|
4000–5000 mAh | — |
|
Height
|
— | 48.50 mm |
|
Width
|
— | 26.50 mm |
|
Depth
|
— | 17.50 mm |
|
Nominal Operating Voltage
|
— | 9.00 V |