FLIR i3 Thermal Camera Replacement Battery 3.7V 2200mAh

Flir i3 / i5 / i7 / IRC40 — 3.7V Li-ion Replacement Battery (1950986)

This 3.7V 2200mAh Li-ion battery replaces OEM part numbers 1950986, T197410, T198470ACC, and T199376ACC. It fits the Flir i3, i5, i7, and IRC40 compact thermal imaging cameras. These cameras are used in building diagnostics, electrical panel inspections, and HVAC troubleshooting where a dead battery mid-inspection is a real problem.

• i3, i5, i7, and IRC40 compatibility: All four models share the same 3.7V single-cell battery bay, connector pinout, and BMS handshake protocol — the thermal detector and display draw from the same rail, so one battery specification covers the entire range.
• Bench tested on actual hardware: We ran this battery under combined detector-heating and display load on the i3 platform. The BMS held steady through the detector warm-up spike and did not trip into protection mode under sustained imaging draw.
• Post-swap warm-up requirement: After fitting a new battery and powering on, allow the camera 60 seconds before taking any readings — the thermal detector needs the internal electronics to reach a stable baseline temperature before the image data is accurate. Skipping this step produces thermal readings that appear valid but carry calibration error.

Flir i-series shutting down mid-inspection on a new battery

The i3 and i5 draw current from two simultaneous loads — the uncooled microbolometer detector array and the LCD display backlight. During a scan, that combined draw peaks sharply, and a BMS with a conservative overcurrent threshold will trip into cutoff before the cell is actually depleted. This looks identical to a flat battery but happens with charge still in the cell. If the camera shuts off and restarts fine after a few seconds, the cell is not the fault — the BMS recovered from a momentary overcurrent trip. This battery's BMS is rated to handle the combined i-series load without nuisance tripping.

Thermal image softening and drift before the low-battery indicator appears

The microbolometer in the i-series is voltage-sensitive — as cell voltage sags under load, the detector's internal reference drifts slightly, producing images that look slightly blurred or show temperature readings that shift without the scene changing. This happens at around 3.5V under load, which is above the low-battery cutoff threshold, so the indicator has not triggered yet. If readings start drifting and the battery indicator still shows green, check actual voltage under load rather than at rest. Swapping to a fully charged cell and re-running the flat-field correction cycle from the camera menu will restore measurement accuracy.