Solac AA3400 Cordless Vacuum Replacement Battery 14.4V 3500mAh

Solac AA3400 / XR210 Series — 14.4V Ni-MH Replacement Battery

This is a 14.4V 3500mAh Ni-MH replacement battery pack for the Solac AA3400, Ecogenic AA3400, XR210, and XR210C cordless handheld vacuums. It slots into the same bay as the original pack and runs the motor at the same voltage rail. Capacity is rated at 50.4Wh from the cell pack.

• AA3400, Ecogenic AA3400, XR210, XR210C compatibility: All four models share the same 14.4V motor architecture and battery bay dimensions. The connector and cell arrangement match across this series, so the pack fits without modification.
• Bench tested on actual hardware: We ran this pack through charge cycles on the XR210C platform and monitored BMS behaviour under load. The protection circuit responded correctly to motor-start current draw and held voltage within spec across sustained suction cycles.
• Dock charging discipline for Ni-MH cells: Ni-MH cells degrade faster under continuous trickle charge than Li-ion. Do not leave the vacuum sitting on the dock permanently. Charge to full, then remove it — Ni-MH cells stored partially charged between uses hold capacity significantly longer than those kept on constant charge.

Cordless vacuum losing suction before the battery indicator reaches low

This happens when the motor draws more current than rated — usually because the filter is partially blocked. A restricted airflow path forces the motor to work harder, pulling voltage down faster than the indicator tracks. The battery reads as healthy while actual voltage under load has already sagged below the motor's operating threshold. Clean or replace the filter first, then retest suction at the same charge level.

Replacement pack not accepting charge from the original Solac dock

Some Solac chargers check for a thermistor signal in the battery pack before initiating the charge cycle. If the dock light does not come on or the pack stays cold after 30 minutes, the charger may not be detecting the pack correctly. Check that the contacts on both the dock and the pack are clean and making firm contact. If the pack voltage reads below 10V with a multimeter, the cells may be in deep discharge — some chargers will not initiate on a pack below that threshold without a manual recovery charge first.