About this replacement
Nightstick 9700 / 9744 / 9746 — 3.7V Li-ion Replacement Battery (9700-BATT)
This is a 3.7V, 10200mAh Li-ion replacement battery for the Nightstick 9700, 9744, and 9746 flashlights. It replaces OEM part 9700-BATT and slots into the same battery compartment as the original. Capacity is sourced from product data at 10200mAh (37.74Wh).
- 9700 / 9744 / 9746 platform compatibility: These three flashlight models share the same cylindrical battery format, voltage rail, and driver circuit expectations. The 9700-BATT form factor — 203.50 x 24.00 x 24.00mm — fits all three without modification.
- Bench tested on actual hardware: We ran this cell through charge, discharge, and turbo-mode draw cycles on the 9700 platform. The BMS held voltage within spec under sustained high-current output and tripped cleanly at low-voltage cutoff without driver oscillation.
- Turbo-mode thermal behaviour: The Nightstick 9700 driver can push high sustained current in turbo mode. Keep the flashlight head clear of enclosed spaces during extended turbo use — heat buildup in the head affects the driver's thermal regulation step-down point, not just comfort.
Why the 9700 steps down output before the battery indicator reads low
The 9700's driver uses brownout protection that monitors cell voltage in real time, not just the charge indicator. When the cell drops below the driver's threshold voltage under load — especially during turbo draw — the driver steps output down to protect the cell before the indicator catches up. This is normal behaviour, not a fault with the battery. If you see premature dimming, switch to a lower mode to keep voltage above the driver's cutoff threshold and the light will hold steady output longer.
Flashlight not powering on after the battery fully discharged
If the 9700 was stored with the battery depleted, the cell may have dropped below the BMS's minimum recovery threshold — typically around 2.5V for Li-ion. At that point, the BMS locks out discharge and the flashlight shows no response. Connect the battery to a charger that supports low-voltage recovery or trickle pre-charge mode; most quality Li-ion chargers will bring the cell back above 3.0V and re-enable the BMS. If the charger shows no recognition of the cell after 30 minutes, the cell has self-discharged past recovery and needs replacement.