Saft LSH20

Saft LSH20 — D‑size 3.6 V Li‑SOCl2 High‑Power Primary Cell

The Saft LSH20 is a spiral‑wound lithium‑thionyl chloride (Li‑SOCl2) cell built for high pulse power and reliable operation in harsh environments. It pairs a typical 13 Ah capacity with a stable 3.6 V output, low self‑discharge, and robust stainless‑steel, hermetically sealed construction. Use it when you need strong pulse currents and dependable performance from deep cold up to high ambient temperatures.

Key specifications (typical)

Nominal voltage	3.6 V
Typical capacity	~13 Ah (to 2.0 V cut‑off at 20°C)
Chemistry	Lithium‑thionyl chloride (Li‑SOCl2)
Form factor	D size, spiral‑wound high‑power
Pulse capability	Up to ~4 A (with proper pulse buffering)
Max continuous current	~1.8 A
Estimated energy	~46.8 Wh (3.6 V × 13 Ah)
Operating temperature	~−60°C to +85°C (−76°F to +185°F)
Self‑discharge	<1%/year at 20°C (storage)
Dimensions (approx.)	Ø 33.4 mm × 61.6 mm
Weight (approx.)	~100 g
Compliance	RoHS, REACH; designed to IEC 60086‑4 (primary lithium safety)

Note: A separate high‑temperature variant (e.g., LSH20‑150) is used for applications up to 150°C. Always verify the exact model and limits in the current Saft datasheet.

When to choose the LSH20

• Need high pulse power (e.g., up to ~4 A bursts) for RF transmission, actuation, or telemetry.
• Operation in harsh or remote environments (AMR/AMI, asset tracking, alarms, oil & gas tools).
• Long storage or standby with low self‑discharge and a long service window.

When to consider alternatives

• Low‑drain, very long life: choose a bobbin‑type D cell such as Saft LS33600 (~17 Ah).
• Very high temperatures (to ~150°C): use the dedicated HT variant (e.g., LSH20‑150).
• Rechargeable requirements: use Li‑ion/NMC or LiFePO4 solutions instead.
• Consumer devices expecting 1.5 V D batteries: do not use; voltage is 3.6 V and not compatible.

Integration and design tips

• Pulse buffering: place a low‑ESR capacitor near the load (e.g., 100–470 µF; increase for >2 A pulses) to keep voltage above device minimum.
• Series/parallel use: only with identical cells from the same lot and state‑of‑charge. Add appropriate fusing/PTC and blocking diodes as needed.
• Thermal effects: capacity and pulse capability fall at low temperatures; warm‑up or larger buffer capacitors may be needed. High temperatures accelerate aging.
• Do not solder directly to the cell. Specify cells with welded tabs or holders.
• Mechanical: allow space for a safety venting path; avoid crushing or deformation.

Quick runtime planning

Approximate runtimes at 20°C, ignoring pulse/temperature derating:

• 10 mA average: ~1,300 h (about 54 days)
• 100 mA average: ~130 h (about 5.4 days)
• 500 mA average: ~26 h
• 1 A average: ~13 h

Pulse example: 2 A for 1 s every 60 s (plus 10 mA idle) ≈ 43 mA average. Expected runtime ≈ 13 Ah / 0.043 A ≈ 300 h (~12.5 days), assuming adequate pulse capacitor and suitable cutoff. Actual results depend on temperature, cutoff voltage, and load profile.

Safety, handling, and shipping

• Primary (non‑rechargeable). Never charge, short, crush, or incinerate.
• Storage: cool, dry, ventilated area, ideally 0–30°C (32–86°F). Keep in original packaging until use.
• Use only within specified temperature range for the exact model purchased.
• Transport as lithium metal cells (UN 3090/3091). Follow IATA/IMDG and local regulations.

Compatibility notes

• Voltage is 3.6 V per cell. Do not substitute for 1.5 V alkaline/zinc‑carbon D cells in consumer products.
• Check device minimum voltage and ripple tolerance; add pulse buffering if the device browns out during transmit/actuation.

Alternatives and related cells

• Saft LS33600 (bobbin, ~17 Ah): best for very low average currents and longest life, lower pulse capability.
• Saft LSH20‑150 or other HT variants: for elevated temperature jobs (e.g., downhole up to ~150°C).
• Hybrid solutions (cell + HLC/supercap): for heavy pulse loads with very low average current.

FAQ

Can I recharge the LSH20?

No. The LSH20 is a primary lithium cell and must never be recharged. Use a rechargeable chemistry if charging is required.

Is it safe to use in place of a regular D battery?

No. The LSH20 is 3.6 V, not 1.5 V. Only use it in equipment specifically designed for Li‑SOCl2 3.6 V cells.

What if my device needs high current bursts?

The LSH20 supports strong pulses when paired with a low‑ESR capacitor near the load. Size the capacitor based on the pulse current and duration to keep voltage above the device’s minimum.

What temperature range can I expect?

The standard LSH20 typically operates from about −60°C to +85°C. For sustained operation near 150°C, select the dedicated high‑temperature variant and confirm limits in the datasheet.

How long can it sit on the shelf?

With <1%/year self‑discharge at 20°C, multi‑year storage is practical. Store cool and dry to maximize service life.