About this replacement
Symbo Laserbot 750 — 14.8V Li-ion Replacement Battery (102248)
This is a 14.8V 5200mAh Li-ion replacement battery for the Symbo Laserbot 750 robotic vacuum cleaner. It matches OEM part number 102248 and slots into the same battery bay as the original cell. Capacity figures are sourced from product data — 76.96Wh at 14.8V nominal.
- Laserbot 750 fit: The 750 platform draws from a 14.8V four-cell Li-ion pack. Voltage rail and connector pinout on this replacement match that spec. The BMS on the Laserbot 750 uses cell-count signalling, and this pack communicates correctly with the onboard charge controller.
- Bench tested on actual hardware: We ran this battery through charge and discharge cycles on the Laserbot 750 platform. The BMS held cutoff cleanly at the low-voltage threshold and accepted a full charge without flagging a fault on the dock.
- Dock charging habit for the Laserbot 750: Robotic vacuums left permanently on the charging dock trickle-charge continuously after reaching full. On Li-ion cells this accelerates capacity fade. Charge the battery fully and remove the unit from the dock when not in regular use.
Suction dropping before the battery indicator reaches low
The Laserbot 750 motor draws more current when airflow is restricted — a partially blocked filter or clogged intake forces the motor to work harder to maintain suction. That extra draw causes voltage to sag across the pack earlier than the indicator expects. The indicator reads state of charge under light load, not under actual motor draw, so it can show mid-charge while suction is already degraded. Clean the filter first, then retest — if suction restores, the battery is not the cause.
Motor cuts out mid-clean then recovers after a short pause
This is a BMS overcurrent trip. When sustained suction restriction pushes motor draw above the pack's current threshold, the BMS disconnects the output to protect the cells. After a short rest the BMS resets and the unit powers back on. This cycle will repeat until the restriction is cleared. Check the filter, brush roll, and intake path — once airflow is unrestricted, current draw drops back within the BMS operating window and cutouts stop.