About this replacement
Highscreen Blast — 3.7V Li-ion Replacement Battery
This is a 3.7V, 1800mAh Li-ion battery for the Highscreen Blast smartphone. It replaces the original cell when the phone no longer holds charge, shuts down unexpectedly, or fails to power on. Capacity is 6.66Wh, matching the original specification.
- Highscreen Blast fit: The Blast uses a removable Li-ion cell on a 3.7V rail with a standard three-contact connector — voltage, ground, and thermistor. This replacement matches that pinout and voltage so the charge IC communicates correctly with the new cell.
- Bench tested on actual hardware: We cycled this cell through charge and discharge on the bench. The BMS held cutoff at the correct low-voltage threshold and accepted a full charge without triggering thermal protection on the charge IC.
- Fuel gauge recalibration on first use: After fitting this battery, disable fast charging and run one complete discharge-to-charge cycle at standard speed. This lets the fuel gauge IC map its coulomb counter to the new cell's actual discharge curve before high-current charging starts.
Sudden shutdown at 20–30% on the Highscreen Blast
When the Blast shuts down with charge still showing on screen, the fuel gauge IC is reading percentage against the old cell's discharge curve. The new cell has a steeper voltage drop under modem and screen load at lower state-of-charge. The phone's charge controller interprets that voltage drop as a hard cutoff, not a percentage reading. One full slow discharge cycle — down to automatic shutdown, then a full charge — lets the coulomb counter reset its baseline against the new cell.
Percentage jumping or reading 0% immediately after installation
A new cell installed after deep storage can sit below the fuel gauge IC's calibration window, causing the OS to report 0% or skip erratically between values. Connect the Blast to a charger and leave it for at least 15 minutes before attempting to power on — the charge IC needs to push the cell above roughly 3.0V before the fuel gauge can lock onto a stable reading. If the phone still reports 0% after 30 minutes on charge, disconnect and reconnect the battery to reset the BMS handshake. After that, run one full charge to 100% without interruption.