Why button battery LR1154 is called LR44?
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"The battery nomenclature is defined by the International Electrotechnical Commission (IEC) in its 60086-3 standard (Primary batteries, part 3 Watch batteries). The letter "L" indicates the electrochemical system used: a zinc negative electrode, manganese dioxide depolarizer and positive electrode, and an alkaline electrolyte. "R44" indicates a cylindrical ("round") cell 11.4±0.2 mm diameter and 5.2±0.2 mm height."

LR44 Battery