The LR44 battery is usually confused with a lithium battery due to the letter L. But LR44 is not a lithium battery, but an alkaline battery. The nomenclature is based on IEC 60086-3 standard in which the first letter stands for the battery chemistry. Accordingly, L stands for alkaline chem...
The LR44 equivalent batteries are A76, AG13 batteries, G13, LR1154, L1154, 154, and so on. You could buy Energizer A76 LR44 on the electronic market. The LR44 battery is similar in size to button cells made of silver oxide (for instance, SR44 batteries, SR44SW, 303, as well as ...