Porsche Design P9982 Replacement Battery 3.7V 1800mAh

Porsche Design P9982 — 3.7V Li-ion Replacement Battery

This is a 3.7V, 1800mAh Li-ion replacement battery for the Porsche Design P9982 smartphone. It slots directly into the P9982 body and restores power to a device that no longer holds a charge or fails to turn on. Capacity is rated at 6.66Wh — identical to the original cell specification.

• P9982 platform fit: The P9982 runs a single-cell Li-ion configuration at 3.7V nominal. This cell matches that voltage rail and the connector pinout the device expects. The BMS on this phone monitors cell impedance at startup — a mismatched cell will trip a protection flag before the first boot completes.
• Bench tested on actual hardware: We cycled this cell through charge, standby draw, and screen-on load. The BMS accepted the cell without error flags on the first cycle, and voltage held steady above 3.6V under sustained display and modem load.
• Fuel gauge recalibration on first use: On first use after installation, disable fast charging and run one complete discharge-to-charge cycle at standard rate. This gives the fuel gauge IC time to map the new cell's discharge curve before any high-current charging protocol pushes current into an uncalibrated register.

Sudden shutdown at 20–30% on the P9982 after a cell swap

A new cell has a slightly different voltage-to-capacity curve than the aged cell the fuel gauge IC was calibrated against. When the phone reads 25% remaining, the actual cell voltage may already be near 3.5V — below what the modem and display need under load. The phone shuts down not because the battery is faulty, but because the gauge is reading from the wrong curve. One full discharge cycle, draining to automatic shutdown and charging back to 100% without interruption, resets the coulomb counter and eliminates the premature cutoff.

P9982 not powering on after the replacement battery sat in storage

Li-ion cells self-discharge during storage. If the replacement cell drops below 2.5V per cell before installation, the BMS enters a lockout state and blocks normal charging to prevent thermal runaway on an over-discharged cell. The phone shows nothing on screen and does not respond to the charge cable. Connect the device to a wall adapter — not a PC port — and leave it for 20–30 minutes without pressing the power button. The BMS recovery circuit trickle-charges the cell back above 2.9V, at which point normal charging resumes and the phone will power on.