LR521 Battery: 1.5V Alkaline, AG0 Equivalent
The 5.8 mm alkaline button cell — LR521 / AG0 equivalents.
Specifications
- Voltage
- 1.5V
- Diameter
- 5.8 mm
- Thickness
- 2.1 mm
- Capacity
- 10 mAh
- Weight
- 0.3 g
- UL
- UN38.3
- CE
- RoHS
- ISO9001
A LR521 replacement is usually a watch or small electronics job — the 5.8 mm diameter is the number to check, as 6.8 mm and 7.9 mm cells look alike in a drawer.
Buying LR521 in bulk? The AG/379A cross-reference is on the pack, so retailers match both naming systems from one stock.
What is a LR521 battery?
LR521 is a button cell rated 1.5V, 5.8 × 2.1 mm, with roughly 10 mAh capacity. Its cross-reference codes are AG0 / 379A. When replacing it, match the voltage and the diameter first — the 5.8 mm size is what decides whether the cell sits correctly in its holder.
| Voltage | 1.5V |
| Capacity | 10 mAh |
| Equivalent & Cross-Reference | AG0 / 379A |
Where it is used
- Watches
- Small electronics
Equivalent & Cross-Reference
- AG0
- 379A
Packing quantities are standard; other formats on request.
LR521 vs AG0
LR521 (IEC) and AG0 (AG-series) are two names for the same 5.8 × 2.1 mm cell. The 379A crossover is the third reference — match any one of them and you have the right cell.
Wholesale & Custom Supply
Factory-direct bulk: LR521 ships 10 pcs per card, 200 pcs per box, private label and custom card counts supported.
Battery Information for the EU Market
For each model we publish its full battery information file under Regulation (EU) 2023/1542 — chemistry system, performance data, hazardous substances statement and related documents.
General Information
- Battery Name
- Alkaline Zn-MnO₂ LR521/LR521H button cell (non-rechargeable)
- Category
- Portable battery
- Chemistry system
- Zn-MnO₂
- Model
- LR521/LR521H
- Trade/Brand name
- TianQiu/No-brand/OEM brands
- Nominal Voltage
- 1.5V
- Production Date
- According to customer requirements, generally printed on the battery body:Y-M For example: 64=2026-04 6X=2026-10 6Y=2026-11 6Z=2026-12
- Shelf Life
- One years under normal storage conditions
- Country of Origin
- China
Manufacturer
European Authorized Representative
- Apex CE Specialists GmbH
- Grafenberger Allee 277, 40237 Düsseldorf, DE
- Contact: Wells Yan
- Email: Info@apex-ce.com
- Tel: +49 2131 206 6043
Battery Characteristics Data Sheet
| Approx. Weight | Capacity | MAD |
|---|---|---|
| 0.2g | 7mAh | 350.0 hours |
◆ Capacity & MAD test condition: 68KΩ 24h/day to 1.2V @ 20±2℃◆ Approx. weight only for reference
Critical Raw Materials
- Manganese
- Graphite
Hazardous Substances & SVHC Statement
No substances listed in the REACH Candidate List of Substances of Very High Concern (SVHC) are present above 0.1% w/w.
Related Documents
Manufacturer: DongGuan Tianqiu Enterprise Co., Ltd. — assessed against Articles 6 & 13 of Regulation (EU) 2023/1542.
FAQ
What is an LR521 battery?
A 1.5V alkaline button cell, 5.8 × 2.1 mm, about 10 mAh typical capacity — also stamped AG0 / 379A.
What is an LR521 compatible with?
AG0 and 379A — same size and voltage, interchangeable.
Is the LR521 mercury-free?
Yes — all TIANQIU alkaline button cells are 0% Hg, verified by an independent mercury-free testimonial.
