379 rental battery mLR521, SR521, 379AG0 button cells are often used in watches, toys, remote controls, and similar low-power devices. These batteries are produced by most, if not all, of the most reputable battery brands and are easy to find if you know what to look for.
Dimensions of type LR521, SR521, AG0: diameter 5.8 mm and height 2.1 mm.
Like most similar button cell batteries, LR521, SR521, AG0 batteries have two main chemical systems:
Alkaline spheres are usually designated as LR512, LR63, AG0, 379etc. - they are recognizable by the prefixes "LR" or "AG", although some manufacturers only use labels with numbers, but also describe the chemical composition of the batteries on the battery packaging.
Rated voltage LR63 / LR512 / AG0The initial voltage is 1.5 volts, but the voltage drops with use. The cutoff voltage depends on the device used, but is typically around 1.0 volts.
Typical capacity alkaline 379is around 10mAh, also depending on the overall temperature, discharge current, battery life, etc.
Silver oxide is usually designated as SR521, SR521, SR521SW, SR63, 379, SG0, and similar models. These differ from alkaline spheres in that they generally have the "SR" prefix, although some brands use "numbers only" labels and similar ones. To attract potential customers, most brands list the model numbers they replace.
Of course, this sometimes increases the confusion about which one to buy, but overall it makes it much easier to find the right replacement.
Power supply battery 379 Nominal voltage of batteries SR521, SR521, SR521SW, SR63, 379, SG0 is 1.55 V, and typical capacityis in the range of 16-18 mAh, which is significantly more than the alkaline typical capacity of 10 mAh.
The cutoff voltage of silver oxide batteries is ~1.2 V, but this also depends on the cutoff voltage of the device used. In any case, silver oxide batteries have a much more stable voltage than alkaline batteries.
Long Story Short: If you need a button cell battery with a diameter of 5.8mm and a height of 2.1mm and you're not sure which one to get, follow these guidelines:
— LR521, LR63, AG0and similar ones are alkaline: cheaper, but have less stable voltage and lower capacity,
— SR521, SR521S, SR521SW, SR63, 379, SG0 and similar ones are silver oxide: they are a little more expensive, but have a more stable voltage and greater capacityIf you have a wristwatch or any similar electronic device, be sure to buy a battery labeled SR521SW. Personally, the price difference between alkaline and silver-oxide batteries is very small, and in my opinion, silver-oxide batteries are worth it.
