Both cr1220 and cr2025 are common.

The first two digits of the battery model indicate the diameter of the battery, and the last two digits indicate the height of the battery (10 times smaller), in mm. In appearance, the height of 2032 is 3.2MM, while that of 2025 is 2.5MM.

CR2032 Diameter: 20.0 mm Thickness (Height): 3.2 mm Capacity: 230 mAh It depends on the size and service life of the two models of batteries. If the size of 3.2 mm or 2.5 mm is not a big problem, and the service life of these two models of batteries is not too high, they can be used universally.

  Rated Capacity:

Under the conditions specified in the design (such as temperature, discharge rate, termination voltage, etc.), the minimum capacity that the battery should be able to discharge, the unit is ampere/hour, expressed by the symbol C. The capacity is greatly affected by the discharge rate, so the discharge rate is often marked with Arabic numerals in the lower right corner of the letter C, such as C20=50, indicating that the capacity at 20 hours is 50 ampere hours.

The theoretical capacity of the battery can be accurately calculated according to the amount of the electrode active material in the battery reaction formula and the electrochemical equivalent of the active material calculated according to Faraday's law. Due to the possible side reactions in the battery and the special needs of the design, the actual capacity of the battery is often lower than the theoretical capacity.