Varta CR1/2AA 3V Lithium

What it is

The Varta CR1/2AA 3V Lithium is a primary lithium-manganese dioxide (Li‑MnO2) cell in the 1/2 AA form factor, also known as 14250 or CR14250. It is built for dependable, long‑duration standby power with the ability to deliver short pulse currents for sensors and control electronics.

When to choose it

• You need long shelf/standby life with low self‑discharge for memory backup or metering.
• Your device operates in wide temperatures (approximately −40°C to +85°C).
• Space is limited and a compact 1/2 AA size is required.
• The device specifies a 3V CR1/2AA (14250) lithium primary cell.

When to avoid (and alternatives)

• High‑drain or frequent heavy pulses: consider larger lithium primaries (e.g., CR2, CR123A) or multiple cells.
• Rechargeable requirement: use NiMH AA/AAA or Li‑ion (e.g., 14500) as specified by the device.
• Devices calling for 3.6V ER14250 (Li‑SOCl2): this 3.0V CR1/2AA is not a safe substitute.

Key specifications (typical)

Chemistry	Lithium‑Manganese Dioxide (Li‑MnO2), primary
Size / Codes	1/2 AA (14250), CR14250, CR1/2AA
Nominal voltage	3.0 V
Typical capacity	~750–950 mAh (load and temperature dependent)
Operating temperature	~−40°C to +85°C
Shelf life	Up to 10 years (room temperature, unopened)
Discharge capability	Best for low to moderate drains; supports short pulses (check device/datasheet)
Dimensions	≈14.5 mm diameter × 25 mm height
Weight	≈8–10 g

Values are approximate and may vary by lot, load profile, and temperature. For critical designs, verify with the official Varta datasheet.

Runtime examples (estimates)

• Constant 20 mA load: 850 mAh ÷ 20 mA ≈ 42 hours.
• Constant 1 mA load: 850 mAh ÷ 1 mA ≈ 850 hours (~35 days).
• Real‑world sensors (µA standby with occasional mA pulses): multi‑month to multi‑year, limited by shelf life and pulse demand.

Actual runtime depends on device cut‑off voltage, pulse currents, temperature, and duty cycle.

Compatible labels

• Use: CR1/2AA, 14250, CR14250 (3V Li‑MnO2)
• Do not use as a replacement for: ER14250 (3.6V Li‑SOCl2), 14500 (AA‑size Li‑ion), CR2, or AA.

Typical applications

• Security sensors and alarm transmitters (PIRs, door/window contacts)
• PLC/RTC memory backup and industrial controls
• Utility meters and data loggers
• Medical monitoring devices (non‑implant), test and measuring instruments

Handling and safety

• Do not recharge, crush, or short‑circuit. Install with correct polarity.
• Store cool and dry in original packaging; avoid direct soldering to the cell (use tabbed versions if needed).
• Do not mix old and new cells or different chemistries.
• Recycle or dispose of through approved battery collection programs. Keep out of reach of children.

FAQ

Is the Varta CR1/2AA rechargeable?

No. It is a primary (non‑rechargeable) lithium battery. Charging can cause leakage or rupture.

Can it replace an ER14250 (3.6V) cell?

No. ER14250 is 3.6V lithium‑thionyl chloride. Substituting a 3.0V CR1/2AA may cause malfunction; follow the device’s specified voltage and chemistry.

What temperatures can it handle?

Approximately −40°C to +85°C, making it suitable for cold storage areas and warm industrial environments.

How long will it last in storage?

Up to 10 years at room temperature in original packaging, thanks to very low self‑discharge.

Does it come with solder tabs?

Some variants are available with tabs or leads. If you need to mount to a PCB, choose a tabbed version—do not solder directly to a bare cell.