About this replacement
Maglite ML150LR / ML150LRX — 6.4V LiFePO4 Replacement Battery (ILIF-3006526)
This is a 6.4V 3200mAh lithium iron phosphate battery for the Maglite ML150LR and ML150LRX rechargeable flashlights. It replaces the original ILIF-3006526 cell pack when capacity has dropped or the battery no longer holds a charge. Voltage and chemistry match the factory spec so the driver circuit operates as intended.
- ML150LR and ML150LRX compatibility: Both models share the same battery bay dimensions, 6.4V voltage rail, and LiFePO4 chemistry requirement. The driver circuit on these lights is tuned to the flat discharge curve of LiFePO4 — swapping in a Li-ion pack at a different nominal voltage will cause premature low-voltage cutoff or inaccurate charge-state readings.
- Bench tested on actual hardware: We cycled this pack through charge and discharge on the ML150LR platform. The BMS held voltage within the expected LiFePO4 flat window and triggered cutoff cleanly at the low end without voltage sag tripping the driver prematurely.
- Turbo mode current draw: Turbo mode on the ML150LR pulls significantly more current than standard or low modes. Running turbo on a partially discharged pack pushes the BMS closer to its low-voltage cutoff threshold faster. Run a full charge cycle before extended turbo use to keep the pack well above that threshold.
Flashlight driver stepping down output before the battery indicator shows low
The ML150LR driver monitors cell voltage continuously and begins stepping down output before the indicator LED signals a low-charge state. This is brownout protection — the driver reduces current draw to keep voltage from collapsing under load. It is not a fault with the battery. If the light dims noticeably in turbo or high mode while the indicator still shows charge remaining, the pack is near the lower edge of the LiFePO4 flat discharge curve. Recharge when you see output step down.
Battery draining significantly faster in turbo mode than expected
Turbo mode on the ML150LR draws roughly five to ten times the current of standard mode. LiFePO4 cells handle high-current discharge well, but capacity delivered at high draw rates is always lower than at moderate rates — this is a chemistry constant, not a defect. If turbo runtime feels short, check that the pack was fully charged before use; the charger LED should show green and cell voltage should read at or above 7.2V on a multimeter before you start. Switching to high or standard mode extends available output from the same charge state.