Asus ZenFone 3 Deluxe C11P1605 Replacement Battery 3.85V 3000mAh

Asus ZenFone 3 Deluxe — 3.85V Li-Polymer Replacement Battery (C11P1605)

This 3.85V, 3000mAh lithium-polymer cell replaces the original C11P1605 battery in the Asus ZenFone 3 Deluxe smartphone. The ZenFone 3 Deluxe launched in 2016 and uses a non-removable battery that degrades after roughly 300–500 charge cycles. This replacement restores full electrical capacity to the phone's processor, display, modem, and peripheral components.

• ZenFone 3 Deluxe fitment: The ZenFone 3 Deluxe uses a specific connector orientation and a BMS handshake tied to the C11P1605 cell specification. This replacement matches the original 3.85V nominal rail, physical footprint (77.15 × 62.66 × 3.22mm), and connector pinout so the phone's charge IC accepts it without error flags.
• Bench tested on actual hardware: We ran this cell through a full charge-discharge cycle on ZenFone 3 Deluxe hardware. The BMS accepted the cell on first connection, charge IC transitioned correctly through CC and CV phases, and the fuel gauge IC registered cell voltage within normal parameters at both ends of the cycle.
• First-cycle fast-charge inhibit: After installation, disable fast charging in Settings → Battery for one complete discharge-charge cycle. The ZenFone 3 Deluxe's fuel gauge IC is calibrated to the old cell's discharge curve. Letting it recalibrate against the new cell at standard current prevents the charge IC from pushing high current into an uncalibrated cell, which can cause early charge termination or inaccurate percentage readings from the first day.

Sudden shutdown at 20–30% on the ZenFone 3 Deluxe after a cell swap

After replacing the C11P1605 cell, some users see the phone cut out while the percentage display still shows 20–30% remaining. This happens because the fuel gauge IC's coulomb counter is still mapped to the old cell's voltage-discharge curve. When the new cell hits a voltage point the IC doesn't recognise as critical, the phone's protection circuit reads a voltage cliff and cuts power before the display catches up. Run two full discharge-charge cycles from 100% down to automatic shutdown and back to 100% at standard charge rate. By the second cycle, the coulomb counter recalibrates and the displayed percentage tracks actual cell voltage accurately.

ZenFone 3 Deluxe not powering on after the replacement battery sat in storage

Li-polymer cells ship at approximately 30–50% state of charge but lose voltage during storage. If the C11P1605 replacement cell has dropped below 2.5V per cell, the BMS enters lockout mode and the phone will not respond to a power button press or show a charging indicator. Connect the phone to a wall adapter — not a PC USB port — and leave it for 15–20 minutes without pressing any buttons. Most BMS circuits on this cell perform a trickle pre-charge recovery at low voltage before unlocking normal charge current. If the charge indicator appears and the phone boots, allow a full charge to 4.35V before normal use.