Although the coin-type batteries CR2016 and CR2032 look similar and provide the same voltage, their sizes and power capacities are different. You find them in a variety of electronic devices such as computers, watches and calculators. While they're not interchangeable, substituting one type for another may work in some devices.
Battery Size and Capacity
The CR2016 and CR2032 batteries both have a diameter of 20 mm, but the CR2016 is thinner, having a maximum thickness of 1.6 mm. The CR2032 is twice as thick, measuring 3.2 mm thick. The CR2032's greater thickness means it contains more lithium-based chemicals and provides 240 milliamp-hours of service life, greater than the CR2016's capacity of 90 mAh.
Because the CR2032 and CR2016 have the same voltage and diameter, it may be tempting to think the batteries are interchangeable. You cannot, however, fill a CR2032 slot with two CR2016s stacked one on top of the other, as this arrangement produces 6 volts, not 3, which may damage the device. If it fits in the device's battery slot and makes a good electrical connection, a CR2016 can substitute for a CR2032, but it will have less than half the CR2032's lifetime.