Button cell battery SEIKO SR521SW 1.55V Silver Oxide, single piece

The SEIKO SR521SW is a single silver-oxide button cell battery with a nominal voltage of 1.55V designed for compact electronic devices. Supplied as one piece, this battery provides stable voltage and consistent discharge characteristics typical of silver-oxide chemistry, making it suitable for precise small-power applications where steady performance is required. The form factor and output are intended for easy replacement in compatible devices without modifying the host equipment.

Advantages

Silver-oxide chemistry delivers a flat discharge curve and stable voltage over most of the battery life, which helps maintain consistent device operation. The SR521SW offers low self-discharge and reliable shelf life, enabling long-term storage before installation. Its compact size and standardized shape allow straightforward replacement in many watches, calculators, medical instruments and key remotes.

Suitable for

• Wristwatches and timepieces
• Calculators and small handheld electronics
• Medical devices with low continuous drain
• Remote controls, key fobs and car key remotes
• Backup memory modules in small consumer devices

Key specifications

• Chemistry: Silver oxide
• Nominal voltage: 1.55 V
• Package: Single cell
• Cell type: Button / coin cell
• Typical use: Low-drain precision electronics

How to use

Before installation, confirm the device compatibility and polarity marking in the battery compartment. Remove the exhausted battery carefully and insert the new SR521SW with the correct orientation, ensuring firm contact with the terminals. After replacement, verify that the device powers on and functions as expected. Dispose of the used battery according to local regulations for battery recycling; do not incinerate or dispose of in household waste.

Usage recommendations

Store unused batteries in a cool, dry place away from direct sunlight and metal objects that could short terminals. Replace batteries in pairs or sets where multiple cells are used together to maintain consistent performance. Keep batteries out of reach of children and follow device manufacturer guidance for service intervals and replacement.