FDK Batteries: Reliable 3V Lithium Primary Power for Industrial Electronics

What they are

FDK CR-series cells use lithium manganese dioxide (Li‑MnO2) chemistry to provide stable 3V primary (non-rechargeable) power. They are built for long-term, low-maintenance service in PLC memory backup, meters, sensors, alarms, and data loggers where predictable behavior and long shelf life matter.

When to choose FDK CR cells

• Use if your device spends most of its time in standby with low average current, requires multi‑year life, and must start reliably after long intervals.
• Use if you need consistent performance across a wide temperature range and prefer cylindrical formats with optional solder tabs.
• Consider alternatives if you need rechargeability (Li‑ion, NiMH), ultra‑low self‑discharge with 10–15+ year service at very low loads (lithium thionyl chloride, Li‑SOCl2), or frequent high‑current pulses without room for a buffer capacitor.

Key characteristics

• Nominal voltage: 3.0 V
• Chemistry: Lithium manganese dioxide (primary)
• Typical self‑discharge: about 1–2% per year at 20–25°C (application and model dependent)
• Operating temperature: typically −20°C to +60°C; some models may support up to +70–85°C (verify in the specific datasheet)
• Formats: popular cylindrical sizes with bare ends or factory‑applied solder tabs

Common sizes and fit notes

Design tips for long life

• Right‑size the energy budget: for multi‑year service, keep average current in the tens of microamps; allow short, higher‑current bursts.
• Add a local buffer: use a low‑ESR capacitor (e.g., 100–1000 µF or a small supercapacitor) to supply RF or motor pulses while the cell handles the baseline load.
• Set conservative cutoffs: many Li‑MnO2 cells remain usable down to ~2.0–2.2 V under load; choose firmware thresholds that preserve margin.
• Mind the temperature: capacity falls at low temperatures; test your duty cycle at the cold extreme and add margin.
• Use tabbed cells or quality holders to minimize contact resistance and improve vibration resistance; avoid direct soldering to bare cell terminals.
• Storage: keep spares at 20–25°C, dry conditions; do not mix old and new cells or different brands in the same device.

Where FDK batteries excel

• Utility and industrial meters that wake periodically to sample or transmit
• Alarm panels and security sensors that must remain ready after long standby
• PLCs and controllers needing nonvolatile memory backup
• Data loggers and environmental/IoT sensors with low average current
• Medical accessories and instruments (non‑life‑support) requiring predictable voltage

Safety and compliance

• Primary cells—do not recharge or short‑circuit.
• Use only within the rated temperature range; keep away from heat and open flame.
• Follow device polarity markings; replace the entire set in series/parallel packs at once.
• Comply with transport regulations (e.g., UN38.3) and recycle according to local laws.

FAQ