About this replacement
Sencor SRV 9790BK — 14.4V Li-ion Replacement Battery (SRX 9701)
This is a 14.4V Li-ion replacement battery for the Sencor SRV 9790BK cordless stick vacuum. It carries the OEM part number SRX 9701 and a capacity of 5200mAh (74.88Wh). It slots into the original battery bay and connects to the vacuum's onboard BMS as the stock cell does.
- SRV 9790BK fit: The SRV 9790BK runs a 14.4V motor rail with a BMS that monitors cell voltage and current draw. This cell matches that voltage and uses the same connector and communication protocol, so the vacuum's power management registers it correctly on first install.
- Bench tested on actual hardware: We ran this cell through charge and discharge cycles on a 14.4V Li-ion test rig. The BMS engaged charge cutoff at the correct upper threshold and held steady voltage output under simulated motor-start current draw without tripping overcurrent protection.
- Dock charging practice on the SRV 9790BK: Do not leave the vacuum sitting on the charging dock continuously after it reaches full charge. The SRV 9790BK dock does not interrupt trickle current when the cell is full, which accelerates capacity fade. Charge to full, then remove it from the dock.
Suction dropping before the battery indicator reaches low
The SRV 9790BK motor draws above its rated current the moment airflow is restricted — a partially clogged filter is the most common trigger. When current spikes, the BMS responds by reducing output voltage to protect the cells, and the motor slows before the battery gauge reflects any charge loss. The indicator reads the state of charge, not the load condition, so suction loss and the low-battery warning do not arrive at the same time. Clean or replace the filter first; if suction recovers immediately, the battery was never the issue.
Motor cuts out mid-clean then recovers after a short pause
This is a BMS overcurrent trip, not a dead battery. When the SRV 9790BK motor sustains a high-draw condition — most often because suction is blocked at the nozzle or the filter is heavily loaded — the BMS cuts output to prevent cell damage. After a brief cool-down, the BMS resets and the motor runs again. The fix is to clear the blockage and inspect the filter before the next run. If trips continue on a clean, unobstructed vacuum, check cell voltage at rest; it should sit above 13.0V on a fully charged pack.