FLIR DM284 Thermal Camera Replacement Battery 3.7V 2500mAh

Flir DM284 / DM285 Imaging Multimeter — 3.7V Li-ion Replacement Battery (TA04-KIT)

This 3.7V, 2500mAh (9.25Wh) Li-ion battery replaces the TA04-KIT and TA04 cells in the Flir DM284 and DM285 Imaging Multimeters. These are handheld thermal imaging devices used for electrical, mechanical, and building diagnostics. The battery slots directly into both models — the voltage rail and connector are identical across the DM284 and DM285 platforms.

• DM284 and DM285 platform fit: Both models share the same 3.7V cell format, connector pinout, and BMS handshake protocol. Swapping between them requires no adapter or firmware change — the protection circuit communicates with either device identically.
• Bench tested on actual hardware: We ran this cell under the combined load of the DM284's thermal detector heating element and the backlit display. The BMS held stable across repeated power cycles and did not trip on start-up draw. Capacity measured within spec at 2500mAh across three full discharge cycles.
• Detector warm-up after battery swap: After fitting a new or fully charged battery, power on the camera and wait 60 seconds before taking any thermal measurements. The infrared detector needs that window to reach its calibrated baseline temperature — readings taken before stabilisation will show drift, not true surface temperatures.

Why the DM284 shuts down mid-inspection on a seemingly charged battery

The DM284 runs two significant power draws simultaneously: the thermal detector's heating element and the colour display. When battery cells age, internal resistance climbs. Under this combined load, voltage can sag below the BMS cutoff threshold — typically around 3.0V per cell — even when the fuel gauge still shows charge remaining. The camera reads available open-circuit voltage, not under-load voltage, so the displayed percentage lags behind reality. Replacing the cell with a fresh 2500mAh unit removes the high-resistance cause and stops unexpected shutdowns.

Thermal accuracy degrading before the low-battery indicator appears

The DM284's uncooled microbolometer detector is voltage-sensitive — its internal reference circuit requires a stable supply above approximately 3.4V to maintain calibrated accuracy. As a Li-ion cell discharges through its mid-range, voltage drops gradually and the detector's baseline can shift before the battery indicator triggers. This shows up as temperature readings that creep a degree or two off against a known reference, not as an obvious fault. If measurements start looking inconsistent during extended fieldwork, check cell voltage directly with a multimeter — a reading below 3.5V under load is the threshold to swap the battery.