About this replacement
Acer Swift 5 SF514-54GT-595G — 15.4V Li-Polymer Replacement Battery (AP18C7M)
This is a 15.4V, 3800mAh (58.52Wh) Li-Polymer battery for the Acer Swift 5 SF514-54GT-595G ultrabook and compatible models including the TravelMate Spin P4 TMP414RN-51-72QA and Swift 3 SF316-51-77LN. It replaces OEM part numbers AP18C7M and KT00407008. Dimensions are 261.00 x 88.20 x 6.00mm — confirm fitment against your original cell before installing.
- Swift 5 / Swift 3 / TravelMate Spin P4 compatibility: These models share the same 15.4V four-cell Li-Polymer architecture, identical connector pinout, and BMS handshake protocol — which is why a single cell covers all of them despite different chassis sizes.
- Bench tested on actual hardware: We ran this cell through charge and discharge cycles on a Swift 5 SF514-54GT unit. The BMS accepted the cell without error flags, and the charge controller reached full termination voltage without tripping.
- First-cycle discharge reset on Swift 5: After installing, let the battery discharge fully to hibernate cutoff, then charge uninterrupted to 100%. This resets the BIOS battery learn cycle and clears the inaccurate health warning that appears in Acer Care Center after every cell swap.
Why the Swift 5 BIOS flags a new battery as poor health immediately after swap
The Swift 5 firmware reads EEPROM data written by the original factory cell during initial calibration. When a replacement cell is installed, that EEPROM record does not match the new cell's charge history, so the BIOS health register shows "poor" or a low percentage. This is a firmware state issue, not a fault with the replacement cell. Running a full discharge-to-hibernate followed by an uninterrupted charge to 100% forces the BIOS to rewrite the learn cycle data against the new cell. After one or two full cycles, the health reading normalises.
Swift 5 shutting down at 20–30% remaining shown on the gauge
This happens when the fuel gauge IC hasn't calibrated against the new cell's voltage curve. The gauge reads 25% but the cell voltage has already dropped below the BMS cutoff threshold under combined CPU and display load — so the system shuts down abruptly. It's not a faulty battery; it's a misaligned voltage-to-percentage map. Run two complete discharge-to-hibernate and full-charge cycles without interruption. After the second cycle, the fuel gauge IC relearns the curve and the shutdowns stop.