CR1620 vs CR1616
The CR1620 and CR1616 are 3 volt lithium coin cells sharing a 16 mm diameter, separated by height: 2.0 mm against 1.6 mm. The extra thickness gives the CR1620 about 76 mAh versus the CR1616's 55. Key fobs, their main habitat, are molded for one specific height.
| CR1620 | CR1616 | |
|---|---|---|
| Chemistry | Lithium manganese dioxide (Li/MnO2) | Lithium manganese dioxide (Li/MnO2) |
| Voltage | 3 V | 3 V |
| Diameter | 16 mm | 16 mm |
| Height | 2 mm | 1.6 mm |
| Capacity | 75-78 mAh | 50-55 mAh |
| Also sold as | DL1620, ECR1620, BR1620 (wide-temp variant) | DL1616, ECR1616, BR1616 (wide-temp variant) |
These two are the heart of the older key fob battery aisle. Honda and Acura remotes of the 1990s to 2010s leaned toward the CR1616, while Toyota, Mazda and Nissan fobs of the same era frequently took the CR1620. But model-year changes scrambled any brand rule, so the only trustworthy identification is the code on the cell inside the fob.
The 0.4 mm difference is right at the edge of what compartments tolerate. Some fob cases with springy contacts close happily over either cell, and there the CR1620's 40 percent capacity advantage makes it the better fill. Cases molded tight to 1.6 mm will not snap shut over a CR1620, and a CR1616 in a 2.0 mm bay can lose contact when the fob is dropped or jostled, resetting or killing the remote intermittently.
Beyond fobs, both sizes serve digital watches, bike computers and heart-rate sensor pods, with identical swap logic. When replacing, note the cell's orientation before removing it; installing a coin cell upside down is the most common cause of a fob that stays dead after a fresh battery.