Streamlight ClipMate USB 3.7V 600mAh Li-Polymer Replacement Battery

Streamlight ClipMate USB — 3.7V Li-Polymer Replacement Battery (61128)

This 3.7V, 600mAh lithium-polymer cell replaces the internal rechargeable battery in the Streamlight ClipMate USB clip-mounted work light. When the original cell degrades after repeated charge cycles, output dims noticeably and charge retention drops. Swapping in a fresh cell restores full brightness and charge capacity.

• ClipMate USB platform fit: The ClipMate USB uses a compact LiPo cell with tight dimensional tolerances — 46.00 × 20.10 × 6.70mm — so the replacement must match both footprint and voltage rail exactly. This cell meets those specs and connects to the onboard charging circuit without modification.
• Bench tested on actual hardware: We cycled this cell through the ClipMate USB's integrated USB charging circuit and confirmed the BMS accepted the cell, reached full charge without fault flags, and delivered consistent output across low and high drive modes.
• LiPo swelling check: LiPo cells in compact housings can swell slightly when aged or over-discharged, pressing against the shell and stressing internal contacts. Before fitting the new cell, check the housing cavity for deformation. If the old cell is visibly puffy, do not attempt to flatten it — dispose of it through a battery recycling point.

ClipMate USB stepping down to low mode before the charge indicator reads empty

The ClipMate USB driver monitors cell voltage continuously and steps output down before the cell hits the protection cutoff. This is intentional — the driver reduces current draw to keep voltage above the BMS floor, extending usable time on the remaining charge. It is not a fault. Once the cell voltage drops below roughly 3.5V under load, the driver will not sustain full output regardless of what the indicator shows. A fresh 600mAh cell pushes this threshold back significantly compared to a degraded original.

ClipMate USB not responding after being left discharged for several weeks

LiPo cells left at or near zero volts for extended periods drop below the BMS re-engagement threshold — typically around 2.5V — and the protection circuit locks out charging as a safety measure. The light will not respond to the USB charge cable at all. To attempt recovery, connect the USB cable and leave it undisturbed for 15–20 minutes; some charger circuits will trickle current into a deeply discharged LiPo to bring it back above 2.8V before switching to normal charge mode. If the charge indicator never activates after 30 minutes, the cell will not recover and needs replacing.