About this replacement
Seagate Wireless Plus — 3.7V Li-ion Replacement Battery (UPF454261S-2S-1AYBA2)
This 3.7V 2800mAh Li-ion battery replaces the internal cell in the Seagate Wireless Plus portable wireless hard drive. It fits models STCK1000100, STCV2000100, and 1AYBA2. When the original cell degrades, wireless streaming and file sharing stop working — this cell restores that function.
- Wireless Plus model compatibility: The STCK1000100 and STCV2000100 share the same internal battery bay geometry, connector pinout, and BMS handshake protocol. One cell covers the full Wireless Plus line without modification.
- Bench tested on actual hardware: We ran this cell through charge and discharge cycles on a Wireless Plus unit. The BMS accepted the cell without fault flags, and the device's charge indicator tracked correctly from 0% to 100%.
- Post-install calibration cycle: After fitting this cell, run a full charge to 100%, then let the device discharge completely through normal use before recharging. The Wireless Plus firmware needs this cycle to calibrate its capacity estimate — skipping it results in inaccurate charge readings from the first session.
Why the Wireless Plus rejects a new cell on first boot
The Wireless Plus management firmware authenticates the battery's BMS data before accepting it as a known cell. A brand-new cell with no charge history can return unfamiliar state-of-charge values, causing the firmware to log an unrecognised battery state. This is not a fault with the cell — it resolves once the firmware completes its first full charge-discharge cycle and updates its internal reference. Allow up to 24 hours of normal use after the first full charge before treating any warning as a real error.
Wireless Plus showing lower capacity than 2800mAh after replacement
If the device reports significantly less than 2800mAh after installation, the firmware calibration cycle has not completed. The capacity estimate is calculated from a charge-discharge baseline that the system builds over the first full cycle — without it, the firmware interpolates from factory defaults, which skews low. Charge the unit fully to 100%, use it until it shuts down from low battery, then recharge to 100% without interruption. After that cycle, the reported capacity will reflect the actual 2800mAh rated capacity of the cell.