About this replacement
Asus Transformer Book T300LA — 3.7V Li-Polymer Replacement Battery (C11N1303)
This 3.7V 550mAh Li-Polymer battery replaces part number C11N1303 in the detachable tablet portion of the Asus Transformer Book T300LA. It fits the tablet unit itself, not the keyboard dock. Capacity is 2.04Wh — matching the original cell specification exactly.
- T300LA tablet unit compatibility: The T300LA keyboard dock carries its own separate battery. This cell powers only the tablet half. The connector and BMS handshake point match the original C11N1303 and 0B200-00370100 references, so the system board recognises the replacement without throwing a hardware flag.
- Bench tested on actual hardware: We cycled this cell through full charge and discharge on a T300LA unit. The charge IC accepted the new cell on the first cycle, BMS communication stayed stable throughout, and no low-voltage cutoff errors appeared during the run.
- Fuel gauge recalibration after swap: After installation, run the tablet down to automatic shutoff, then charge uninterrupted to 100% without using the device. This gives the fuel gauge IC one complete data set against the new cell and clears the inaccurate percentage readings that almost always appear immediately after a battery swap.
Why the T300LA tablet shuts down at 15–25% remaining
The T300LA tablet drives a high-resolution display and maintains a WiFi connection simultaneously. Under that combined load, voltage sags faster than the fuel gauge IC predicts — especially when the gauge is still calibrated to the old, degraded cell. The BMS reads the voltage cliff as a near-empty state and triggers an emergency cutoff before the displayed percentage reaches zero. Running one full discharge-to-shutoff cycle after fitting this replacement resets the gauge threshold and brings the cutoff point back down to the correct level.
Percentage dropping faster than expected from 100% after replacement
This is fuel gauge drift — the IC stored discharge curve data from the old cell and is now misreading the new one. It does not mean the replacement battery is faulty or underspec. The fix is one complete recalibration cycle: discharge to automatic shutoff, then charge to 100% without interruption. After that cycle the gauge reads against the actual capacity of the new cell, and the percentage drop rate normalises to what you would expect from a 550mAh Li-Polymer cell.