About this replacement
Acer Aspire Timeline 3810T Series — 10.8V Li-ion Replacement Battery (AS09D34)
This is a 10.8V, 6600mAh (71.28Wh) Li-ion battery for the Acer Aspire Timeline 3810T and 3810TZ notebooks. It replaces OEM part numbers AS09D34, AS09D36, AS09D56, AS09D70, and over a dozen BT.006xx codes used across the 3810T range. The connector, cell count, and BMS handshake match the original Acer specification.
- 3810T and 3810TZ compatibility: Both models run the same 3-cell series Li-ion architecture, 10.8V nominal rail, and share the same physical connector and BMS communication protocol — which is why one cell covers both variants and all sub-models like the 3810T-6415 and 3810T-8640.
- Bench tested on actual hardware: We ran this cell on a 3810T unit and confirmed the BMS negotiated correctly with the EC, charge current stepped down at 95% as expected, and the pack reached full charge without triggering a fault code.
- Post-install calibration on the 3810T: After fitting this cell, run one full discharge to hibernate-cutoff, then charge uninterrupted to 100%. This resets the BIOS battery learn cycle and clears the inaccurate health warning that appears after every cell swap on this platform.
BIOS reporting poor battery health immediately after fitting a new cell
The 3810T BIOS reads health data stored in the battery's EEPROM, not live cell voltage. When a new cell arrives, its EEPROM may report factory-default or mismatched cycle count data that the BIOS interprets as a degraded pack. This is not a cell fault. Running one full discharge-to-hibernate followed by a complete uninterrupted charge gives the BIOS enough data to rewrite its internal battery model and clear the warning. After two or three cycles the health reading stabilises.
Laptop shuts down at 20–30% charge shown on screen
This happens when the fuel gauge IC hasn't calibrated against the new cell's actual voltage curve. The IC still uses the old cell's discharge profile, so it miscalculates the remaining capacity and signals a low-battery shutdown too early. The fix is the same calibration cycle — discharge fully to hibernate, then charge to 100% without interruption. After two full cycles the gauge IC locks onto the new cell's curve and the early shutdowns stop. If it persists past three cycles, check that the BIOS is not running a charge-limit firmware setting capping the cell below its rated 10.8V endpoint.