FLIR One Thermal Camera Compatible Battery 3.7V 185mAh SDL352054

Flir One / One 2st — 3.7V Li-Polymer Replacement Battery (SDL352054)

This 3.7V 185mAh (0.68Wh) Li-Polymer battery replaces the OEM SDL352054 cell inside the Flir One and One 2st thermal camera. The Flir One clips to a smartphone and powers both the thermal detector array and onboard image processing. When the original cell degrades, thermal accuracy drops before the battery indicator reaches red.

• One and One 2st compatibility: Both generations share the SDL352054 cell format, the same 3.7V supply rail, and the same compact body dimensions. The 54.00 × 20.54 × 3.60mm profile fits the internal cavity without modification.
• Bench tested on actual hardware: We cycled this cell under combined detector-plus-display load. The BMS held stable voltage through the full draw cycle and tripped protection correctly at the low-voltage threshold without premature cutoff.
• Thermal detector warm-up: After powering on, allow 60 seconds before starting any inspection. The thermal detector needs that window to reach a stable internal temperature — readings taken before stabilisation will show baseline drift that looks like a hardware fault.

Why the Flir One cuts out mid-inspection on a freshly charged battery

The Flir One draws current from two sources simultaneously — the thermal detector's heating element and the display pipeline feeding frames to the smartphone. On an aged cell, this combined load causes voltage to sag below the BMS protection threshold even when the battery indicator still shows partial charge. A replacement cell with a healthy internal resistance handles the combined draw without tripping. If shutdowns persist after replacement, check that the smartphone USB connection is clean — a resistive contact forces the camera to pull harder from the internal cell.

Thermal image looking washed out or low-contrast before the battery reads empty

The Flir One's thermal detector is voltage-sensitive. As cell voltage sags under load — even while the indicator still shows green — the detector's bias voltage drops and temperature resolution degrades. The result looks like reduced contrast or a flattened colour palette, not a dead battery. Swap the cell and check that resting voltage measures at or above 3.7V before installation. If the new cell rests below 3.5V out of the box, run one full charge cycle before use.