About this replacement
Bright Star LightHawk — 7.4V Li-ion Replacement Battery (07880)
This is a 7.4V, 7800mAh (57.72Wh) Li-ion battery for the Bright Star LightHawk flashlight. It fits models 07802, 07815, 07816, and several additional LightHawk variants that share the same battery bay and connector. If your LightHawk no longer holds charge or cuts out under load, this is the direct swap.
- LightHawk 07802, 07815, 07816 platform: These models share the same 7.4V dual-cell configuration and battery connector format. The BMS handshake and charge termination logic are consistent across the series, so a single battery spec covers the full compatible range without firmware conflicts.
- Bench tested on actual hardware: We ran this battery through charge and discharge cycles on compatible LightHawk hardware. The BMS handled turbo-mode current draw without tripping undervoltage cutoff prematurely, and cell balance held within spec across multiple cycles.
- Multi-cell replacement tip: The LightHawk pack uses two cells in series. Never mix this new pack with a partially depleted original — the weaker cell will drain first under high-current turbo draw, creating a voltage imbalance that accelerates cell degradation in the weaker unit.
Why the LightHawk steps down from turbo before the battery indicator moves
The LightHawk driver monitors cell voltage in real time, not just overall pack percentage. In turbo mode, current draw is high enough to cause a temporary voltage sag across the cells. When that sag crosses the driver's brownout threshold — typically around 6.8–7.0V under load — the driver steps output down to protect the cells, even if the indicator still reads partial charge. This is normal driver behaviour, not a battery fault. Switching to a mid-level mode lets the pack voltage recover and sustains output longer before the next step-down.
LightHawk flickering between modes at end of charge
Mode cycling near end of charge happens when pack voltage drops close to the driver's minimum operating threshold. The driver cuts power briefly, the cells recover slightly, voltage rises, and the driver restarts — repeating rapidly as a visible flicker or mode oscillation. This is the BMS and driver interacting at the edge of cutoff voltage, not a faulty battery or driver. When this starts, switch immediately to low mode. Turbo and high modes are no longer viable at that state of charge — the pack voltage under those loads will sit below 6.8V.