Xeno Batteries

Xeno Batteries: When to Use Them and How to Design with Them

Xeno Batteries (Xeno Energy) specialize in lithium‑thionyl chloride (Li‑SOCl₂) primary cells. These 3.6V batteries deliver long service life, very low self-discharge, and reliable operation across harsh temperatures—ideal for smart metering, asset tracking, industrial sensing, and security devices that must run for years without maintenance.

Use If / Avoid If

• Use if your device averages microamps to a few milliamps and needs multi‑year runtime (e.g., water/gas meters, remote sensors, data loggers).
• Use if you need dependable cold/heat performance (about -55°C to +85°C) and low self‑discharge (≈≤1%/year at 20°C).
• Avoid if you require rechargeability or continuous high drains (typically tens to hundreds of mA continuously). Consider rechargeable Li‑ion or LiFePO₄ for high‑drain or frequently recharged devices.
• Avoid if your design expects frequent, long pulses without a buffer capacitor. Use a pulse‑cap or a pulse‑optimized cell/pack.

Key Specs at a Glance

Parameter	Typical value
Nominal voltage	3.6 V
Self-discharge	≈≤1% per year at 20°C
Operating temperature	About -55°C to +85°C (check datasheet by model)
Cell formats	1/2AA, 2/3A, AA, C, D, and custom packs
Example capacities	1/2AA ≈1.2 Ah, AA ≈2.4 Ah, D ≈19 Ah (model dependent)
Cell design	Bobbin (max runtime, low drain) and spiral/pulse‑optimized (higher pulse capability)

Choosing the Right Cell

• Bobbin cells (e.g., compact 1/2AA, AA, D): best for ultra‑low average current and longest life. Limited pulse output without buffering.
• Pulse‑optimized cells or packs: use when your device transmits periodically (e.g., LoRa/2G/NB‑IoT) and needs short bursts. Add a low‑ESR capacitor near the load.
• Packs: for higher voltage or capacity, use factory‑built series/parallel packs to ensure matched cells, fusing, and protection.

Runtime Planning (Quick Examples)

Estimate runtime from average load. Always derate for temperature, pulse demand, and end‑of‑life voltage requirements.

1. Low‑power sensor: 50 µA average.
   • AA (~2.4 Ah): 2.4 Ah / 0.00005 A ≈ 48,000 h ≈ 5.5 years (before derating).
   • D (~19 Ah): 19 Ah / 0.00005 A ≈ 380,000 h ≈ 43 years. Practical planning: 10–15 years due to shelf life and conditions.
2. Smart meter: 100 µA average + a 200 mA pulse for 1 s per day.
   • Base: 0.1 mA × 24 h = 2.4 mAh/day
   • Pulse: 200 mA × (1/3600 h) ≈ 0.056 mAh/day
   • Total: ~2.46 mAh/day ≈ 0.9 Ah/year ⇒ D (~19 Ah) theoretical ~21 years; plan ~10–15 years with margin and temperature effects.

Design and Integration Tips

• Pulse support: Add a low‑ESR capacitor (often 100–1000 µF, value depends on pulse width/temp) close to the radio or load. Validate under worst‑case cold conditions.
• Passivation: After long storage, initial voltage sag can occur. A brief preload or staged startup helps de‑passivate. Test your startup sequence at low temperature.
• Series/parallel: Use matched cells and consider packs with cell fusing and protection. For series stacks, account for balancing and maximum open‑circuit voltage.
• Temperature: Capacity and pulse capability drop in cold. Size cells and capacitors accordingly; verify minimum operating temperature in the datasheet.
• Storage: Keep in original packaging, cool and dry (typically 20–25°C). Avoid high heat and short circuits. Do not store installed in a device that periodically wakes unintentionally.

Safety and Handling

• Non‑rechargeable: Never charge Li‑SOCl₂ cells. Charging can cause venting or fire.
• Short‑circuit protection: Prevent shorts; use insulated holders and correct polarity. Include appropriate fusing in packs.
• Disposal/Recycling: Follow local battery recycling or hazardous waste rules. Do not incinerate or crush.
• Transport: Primary lithium cells are regulated (e.g., UN 3090/3091). Follow packaging, labeling, and state‑of‑charge requirements for shipping.

Alternatives and Compatibility

• Rechargeable Li‑ion/LiFePO₄: Better for high‑drain or frequently charged systems; shorter standby life than Li‑SOCl₂.
• Alkaline: Lower cost and easy to source, but poorer cold performance, lower energy density, and higher self‑discharge.
• Consumer lithium (e.g., CR123A): Different form factors and pulse behavior; not a drop‑in replacement for industrial Li‑SOCl₂ designs.

FAQs

Are Xeno Batteries rechargeable?

No. Xeno’s Li‑SOCl₂ cells are primary (non‑rechargeable). Do not charge them.

How long can they power my device?

Many designs achieve 5–15 years depending on average current, pulse size, temperature, and cut‑off voltage. Use your device’s true average load to estimate and include safety margin.

Can they handle radio transmission pulses?

Yes, with proper design. Bobbin cells require a pulse capacitor; pulse‑optimized cells/packs may supply higher bursts. Validate at the lowest operating temperature.

What temperatures do they support?

Typical operation is about -55°C to +85°C, model dependent. Check the datasheet for exact limits and derating in cold.

How should I store and ship them?

Store cool and dry in original packaging. For shipping, comply with lithium battery transport regulations (e.g., UN 3090/3091) and carrier rules.