About this replacement
Koehler Lighthawk LED Series — 7.4V Li-ion Replacement Battery (9B-1962-1)
This is a 7.4V, 5200mAh Li-ion replacement for the Koehler Lighthawk LED and Lighthawk Vision LED flashlights. It fits a broad range of Koehler torch models including the 07712 and 07732. The OEM part number is 9B-1962-1.
- Lighthawk platform compatibility: The Lighthawk LED and Vision LED share a common 7.4V dual-cell architecture with identical connector pinout and BMS handshake protocol. That shared platform is why one battery covers all models in this line.
- Bench tested on actual hardware: We cycled this battery on Lighthawk-platform torches and confirmed the BMS negotiates correctly across turbo, high, and low driver modes without false low-voltage cutoffs at normal operating temperatures.
- Multi-cell replacement timing: This pack contains two Li-ion cells in series. If your light uses more than one of these packs, replace all packs at the same time from the same production batch. Mixing a fresh pack with a partially degraded one puts unequal load on the weaker pack under high-current turbo draw, accelerating cell stress in the older unit.
Turbo mode cutting out long before the battery shows low
Turbo mode on Lighthawk-platform torches can pull 5–10 times the current of standard mode. As the battery ages and internal resistance rises, voltage sags under that load and the driver's brownout threshold triggers — stepping the light down before the state-of-charge indicator registers a problem. This is the driver protecting the LED array, not a gauge error. A fresh 5200mAh pack with lower internal resistance sustains the voltage rail long enough for turbo to run full cycles.
Flashlight cycling through modes on its own near end of charge
Mode-cycling near the bottom of a charge cycle happens when pack voltage drops close to the driver's minimum input threshold. The driver briefly loses regulation, resets, and restarts in its default mode — repeating until you manually switch to low. This is not a firmware fault. It is the driver protecting itself from undervoltage. When it starts cycling, switch to low mode immediately and charge the pack; the BMS should accept charge once resting voltage is above 6.0V.