Renata 319 (SR527SW) Silver‑Oxide Watch Battery

The Renata 319 is a 1.55 V silver‑oxide button cell in the SR527SW size (≈5.8 mm diameter × 2.7 mm height). It is optimized for low‑drain analog watch movements and compact instruments that call for a stable, flat discharge curve.

At a glance

• Chemistry: Silver‑oxide (mercury‑free)
• Nominal voltage:1.55 V
• Size code: SR527SW (Renata 319)
• Dimensions: ~5.8 mm (D) × ~2.7 mm (H)
• Drain profile: SW = low‑drain (analog watches)
• Typical capacity: ~15–20 mAh (manufacturer/model dependent)
• Compliance: Mercury‑free, RoHS

When to choose vs. avoid

Choose the 319 (SR527SW) if:

• Your watch or device explicitly specifies SR527SW or “319.”
• You have a low‑drain analog movement (no continuous heavy loads).
• You need the 2.7 mm height (more capacity than thinner SR516SW while keeping the same 5.8 mm diameter).

Consider alternatives if:

• Your device specifies SR527W (high‑drain “W”) rather than SW.
• The watch calls for a different thickness, such as SR516SW (≈1.6 mm) or SR521SW (≈2.1 mm).
• You’re considering an alkaline button cell of the same size—these have lower, declining voltage and shorter life; use silver‑oxide for best accuracy.

Expected runtime

Actual life depends on the movement and condition of the watch. As a rule of thumb for analog watches:

• Typical service life: about 12–24 months
• Higher draw (e.g., larger hands, complications, aged lubricants): toward the lower end
• Well‑serviced movements with modest draw: toward the upper end

Compatibility notes

• Match size exactly: The 5.8 mm diameter must fit the battery well; the 2.7 mm height is critical for contact pressure and case closure.
• SW vs. W: SW is for low‑drain analog use. Some devices specify W (high‑drain). Use what the device manual states.
• Avoid mixing chemistries: Do not substitute alkaline or rechargeable cells; they differ in voltage behavior and can cause poor accuracy or damage.

Pros and cons

• Pros: Stable 1.55 V output, good shelf life, mercury‑free, reliable fit for SR527SW designs.
• Cons: Not suitable for high‑drain devices; lifetime is shorter than larger‑format watch cells due to small size.

Quick installation guide

1. Confirm the required size: SR527SW/319 in the device manual.
2. Open the case carefully; protect gaskets and note battery orientation (polarity).
3. Handle the cell with non‑metal tweezers; avoid shorting the surfaces.
4. Seat the battery firmly with correct polarity; ensure clips/springs are secure.
5. Inspect and replace worn gaskets; reseal the case and verify operation.

Storage and shelf life

• Keep in original, unopened packaging until use.
• Store in a cool, dry place (ideally 10–25°C / 50–77°F), away from humidity and heat.
• Rotate stock by date code; silver‑oxide cells typically keep 4–6 years in proper storage.

Safety and disposal

• Button cells present a choking and ingestion hazard. Keep away from children and pets.
• Do not recharge, disassemble, or expose to fire.
• Recycle through local battery collection programs; do not dispose of in household trash where restricted.

FAQs

How long does a Renata 319 typically last?

In a healthy analog watch, expect roughly 12–24 months. Complications or higher current draw will shorten life.

What is the difference between SW and W?

SW denotes low‑drain use (analog watches). W indicates a high‑drain variant for devices with heavier current needs. Use the type specified by the manufacturer.

Can I use an alkaline button cell instead?

Not recommended. Alkaline cells of the same size deliver lower and declining voltage, reducing accuracy and runtime compared with silver‑oxide.

Is the 319 rechargeable?

No. Do not attempt to recharge; use only as a primary (single‑use) cell.

What sizes are often confused with SR527SW?

SR516SW (≈5.8 × 1.6 mm) and SR521SW (≈5.8 × 2.1 mm). They share the same diameter but are thinner; using the wrong height can cause poor contact or case fit.