CR2032 vs CR2016: twice the thickness, and one trap to avoid

CR2032 vs CR2016

The CR2032 and CR2016 are 3 volt lithium coin cells with the same 20 mm diameter but very different builds: 3.2 mm and 220-plus mAh against 1.6 mm and about 90 mAh. They rarely interchange, and devices that stack two CR2016s must never receive one CR2032.

CR2032 vs CR2016 at the same scale: 20 mm across, 3.2 mm thick against 20 mm across, 1.6 mm thick.

	CR2032	CR2016
Chemistry	Lithium manganese dioxide (Li/MnO2)	Lithium manganese dioxide (Li/MnO2)
Voltage	3 V	3 V
Diameter	20 mm	20 mm
Height	3.2 mm	1.6 mm
Capacity	220-240 mAh	85-90 mAh
Also sold as	DL2032, ECR2032, 5004LC, KCR2032	DL2016, ECR2016, BR2016 (wide-temp variant), 5000LC

The CR2016 is exactly half the CR2032's thickness, which creates the one genuinely dangerous confusion in the 20 mm family. Plenty of LED lights, novelty gadgets and a few remotes are designed around two CR2016 cells stacked in series, producing 6 volts in a stack 3.2 mm tall. That stack has the same footprint as a single CR2032, and a CR2032 slides into the space perfectly, but it supplies half the voltage. The device then glows dimly or does nothing, and the owner concludes the new battery is dead.

When a device uses a single cell, the swap logic is mechanical. A CR2016 in a CR2032 holder usually sits too loose to keep contact; a CR2032 will not fit a compartment molded for 1.6 mm at all. Some spring-contact holders tolerate the mismatch, but with 90 mAh against 230, the thin cell is always the short-lived option.

Count the cells when you open any 20 mm compartment. Two thin cells means buy two CR2016s (or CR2025s if that is what came out) and replace both together with the same brand and date. One cell means match its exact code. The diameter never varies in this family; thickness is everything.

Frequently asked questions

Can one CR2032 replace two CR2016 batteries?

No. Two stacked CR2016s deliver 6 V; one CR2032 delivers 3 V in the same physical space. The device will be dim, weak or completely dead at half voltage. Always replace a stacked pair with a new pair of the same type.

Can a CR2016 work in place of a CR2032?

Rarely well. It is 1.6 mm thin against a 3.2 mm cavity, so contact is unreliable unless the holder has a strong spring, and its 90 mAh capacity is less than half. As a same-day stopgap it may limp along; fit the right cell soon.

Why do some devices use two CR2016s instead of one CR2032?

Voltage. Two cells in series give 6 V, which drives LEDs brighter and simplifies circuits, in the same 20 x 3.2 mm space one CR2032 occupies. The trade-off is lower total capacity and the eternal risk of someone replacing the pair with a single 3 V cell.