About this replacement
Amazon Kindle Paperwhite 4 2018 — 3.8V Li-Polymer Replacement Battery (ST22)
This 3.8V, 1500mAh Li-Polymer battery replaces the original ST22 cell in the Amazon Kindle Paperwhite 4 (10th Generation, 2018). It fits the PQ94WIF board variant and matches OEM references 58-000246 and 58-000271. If your Paperwhite drains overnight on standby or won't hold charge through a reading session, this cell addresses a degraded original battery.
- Paperwhite 4 and 10th Gen compatibility: These model designations share the same board layout, connector orientation, and BMS handshake protocol — all confirmed against the ST22 footprint at 70 × 66 × 2.60mm. No connector adapters needed.
- Bench tested on actual hardware: We ran the cell through charge and discharge cycles on a Paperwhite 4 unit. The charge IC accepted the cell without error flags, BMS cutoff triggered correctly at low voltage, and capacity readout stabilised after one full cycle.
- Fuel gauge recalibration after install: After fitting this battery, let the Paperwhite discharge to automatic shutoff — don't force it off — then charge uninterrupted to 100% without using the device. That single cycle resets the fuel gauge IC against the new cell and eliminates the incorrect percentage readouts that appear immediately after a swap.
Kindle Paperwhite shutting down between 15% and 25% remaining
The Paperwhite's fuel gauge IC learns the voltage-to-capacity curve of the original cell over time. A new cell has a slightly different discharge curve, so the IC miscalculates the remaining capacity and triggers shutdown too early. This is not a fault with the replacement cell. Running one complete discharge-to-shutoff followed by a full uninterrupted charge corrects the stored curve. After that cycle, the device should reach 0% before shutting down.
Paperwhite showing incorrect battery percentage immediately after swap
The onboard fuel gauge IC retains calibration data from the old degraded cell. When a new cell is installed, the stored data no longer matches the actual cell state, so the percentage reading is unreliable — often jumping or reading high while the device still shuts down unexpectedly. The fix is a recalibration cycle: discharge fully to automatic shutoff, then charge to 100% without interruption. Check the percentage at 3.8V open-circuit — if it reads close to 100%, calibration has completed correctly.