About this replacement
Highscreen Zera F — 3.7V Li-ion Replacement Battery (Zera F)
This is a 3.7V, 1600mAh Li-ion battery for the Highscreen Zera F smartphone. It replaces the original cell when the existing battery degrades, swells, or can no longer hold a usable charge. Capacity is 5.92Wh, matching the stock specification for this handset.
- Zera F platform fit: The Zera F uses a compact 62.20 × 46.20 × 5.30 mm cell footprint with a fixed connector orientation. This replacement matches that footprint exactly, so the connector seats without forcing and the battery cover closes flush.
- Bench tested on actual hardware: We cycled this cell through full charge and discharge on a Zera F unit. The BMS accepted the charge handshake without fault codes, and voltage held stable across screen-on and modem-active load phases.
- Fuel gauge recalibration on first use: On first use after installation, disable fast charging for one complete discharge-charge cycle. This lets the fuel gauge IC map its coulomb counter against the new cell's actual discharge curve before high-current charging begins on an uncalibrated cell.
Sudden shutdown at 20–30% on the replacement cell
This happens when the fuel gauge IC is still calibrated to the old cell's discharge curve. The new cell hits a voltage cliff under modem or display load that the gauge didn't predict, so the phone cuts power before the reported percentage reaches zero. It is not a faulty battery — it is a calibration mismatch. Run one full discharge to automatic shutdown, then charge uninterrupted to 100% to let the coulomb counter reset against the new cell.
Phone won't power on after the replacement cell sat in storage
Li-ion cells self-discharge in storage. If this battery sat long enough, the BMS may have tripped into lockout below 2.5V per cell to prevent damage. The phone will show nothing — no charging animation, no response. Connect the phone to a wall charger, not a PC port, and leave it for 20–30 minutes before attempting to power on. A wall charger supplies enough current to push the BMS out of lockout and begin a recovery charge cycle.