About this replacement
Lenovo K5s — 3.85V Li-Polymer Replacement Battery (BL295)
The BL295 is a 3.85V, 3000mAh lithium-polymer cell that fits the Lenovo K5s, K5s TD-LTE Dual SIM, and PADL0006CN. It replaces a degraded original battery that no longer holds charge under screen and modem load. Physical dimensions are 79.00 × 59.20 × 3.72mm — confirm clearance before seating the cell.
- K5s and PADL0006CN compatibility: These variants share the same battery bay geometry, connector pinout, and BMS handshake protocol — one cell covers all three listed models without adapter or modification.
- Bench tested on actual hardware: We cycled the BL295 through charge and discharge on K5s hardware. The BMS accepted the charge IC handshake without error, held voltage above 3.6V through most of the discharge curve, and tripped protection correctly at the low-voltage threshold.
- First-cycle fast charge protocol: On first use after installation, disable fast charging and run one complete discharge-charge cycle at standard rate. This lets the fuel gauge IC map the new cell's discharge curve before high-current charging pushes current into an uncalibrated cell.
Sudden shutdown at 20–30% on the replacement cell
This is a voltage cliff, not a defect. Under modem TX bursts or full-brightness screen load, a new cell that hasn't been calibrated will sag below the shutdown threshold while the OS still reports 20–30% remaining. The fuel gauge IC inherited the old cell's charge curve and is misreading state-of-charge. Run two full discharge-charge cycles without fast charging and the shutdown floor will shift down to match the new cell's actual capacity.
OS battery percentage jumping erratically after cell swap
The K5s fuel gauge IC uses a coulomb counter calibrated to the original cell's internal resistance profile. A new cell has different impedance, so the counter loses tracking accuracy and the displayed percentage jumps or resets unexpectedly. This corrects itself after one full discharge to below 5% and a full uninterrupted charge to 100% — do not unplug mid-cycle. After that cycle, percentage reporting stabilises against the new cell's actual curve.