Founder T410IU-T300AQ Replacement Battery 11.1V 4400mAh

Founder T410IU-T300AQ / T410TU — 11.1V Li-ion Replacement Battery

This is an 11.1V Li-ion replacement battery rated at 4400mAh (48.84Wh) for the Founder T410IU-T300AQ and T410TU laptops. It slots into the existing battery bay and connects through the standard multi-pin connector on these models. Voltage and capacity match the original cell specification exactly.

• T410IU-T300AQ and T410TU compatibility: Both models share the same 11.1V three-cell series architecture, identical bay dimensions, and the same connector pinout. A single cell works across both because the BMS handshake and charge profile are uniform across this Founder notebook line.
• Bench tested on actual hardware: We ran this cell through charge and discharge cycles on the T410 platform. The BMS communicated correctly with the system, charge accepted without fault flags, and the fuel gauge IC tracked state-of-charge across the full voltage range from 12.6V full to the low-voltage cutoff at approximately 9V.
• First-cycle conditioning on the T410 platform: After fitting, run the laptop on battery only until it hibernates at low charge, then charge uninterrupted to 100% without interruption. This gives the fuel gauge IC a full sweep of the new cell's voltage curve and clears the inaccurate health warning the BIOS flags after every cell swap.

BIOS reporting poor battery health immediately after fitting a new cell

The Founder T410 BIOS reads health data stored in the battery's EEPROM and compares it against cycle count and capacity history from the previous cell. A fresh cell arrives with factory EEPROM defaults that don't match the system's stored learn data, so the BIOS flags it as degraded. This is a data mismatch, not a fault with the new battery. Run one full discharge-to-hibernate cycle followed by a full uninterrupted charge to 100% — this triggers the BIOS battery learn cycle and rewrites the health registers against the new cell's actual capacity.

Laptop shuts down abruptly at 20–30% charge shown on the gauge

This happens when the cell can no longer sustain voltage under combined CPU and display load, even though the fuel gauge still reads 20–30% remaining. The voltage drops sharply — a cliff rather than a gradual slope — and the system hits the BMS undervolt cutoff before the gauge catches up. It is a calibration gap between the fuel gauge IC and the new cell's actual discharge curve. Run two full discharge-to-hibernate cycles followed by full charges; the fuel gauge IC recalibrates its curve model against the new cell and the premature shutdown stops appearing after roughly the second full cycle.