About this replacement
Acer Tempo DX650 — 3.7V Li-ion Replacement Battery (848WS00575)
This is a 3.7V, 1260mAh Li-ion battery for the Acer Tempo DX650 smartphone. It replaces OEM part numbers 848WS00575, BT.00101.001, and BT.00107.001. Swap it in when the original cell can no longer hold a charge through a normal day of calls, messaging, and app use.
- Tempo DX650 fitment: The DX650 uses a fixed connector pinout that carries both charge current and fuel gauge data. This replacement matches that pinout, so the phone's charge IC and fuel gauge IC can communicate with the cell from the first boot.
- Bench tested on actual hardware: We cycled this cell through charge and discharge on the DX650 platform and confirmed the BMS handshake completed cleanly. The charge IC accepted the cell without throwing a fault, and capacity read correctly after one full conditioning cycle.
- Fuel gauge recalibration on first use: On first installation, disable fast charging if your firmware supports it and run one full discharge-to-charge cycle before normal use. The fuel gauge IC is still calibrated to your old cell's discharge curve — one complete cycle resets the coulomb counter against the new cell's actual characteristics.
Sudden shutdown at 20–30% on the Tempo DX650
This is a voltage cliff problem, not a capacity problem. When the modem transmits or the screen brightness spikes, instantaneous current draw pulls the cell voltage below the BMS cutoff threshold — even if the fuel gauge still shows charge remaining. A degraded or uncalibrated cell has higher internal resistance, so the voltage drop under load is steeper and faster. After installing a replacement cell, run one full discharge cycle so the fuel gauge IC maps the new cell's actual voltage-to-capacity curve and stops tripping the cutoff prematurely.
Device not powering on after the battery sat in storage
If a replacement cell ships in a low-charge state and sits unused for several weeks, the cell voltage can drop below 2.5V — the point where the BMS locks out to prevent damage. The phone will not respond to the power button and may show nothing on screen even when plugged in. Connect the phone to a wall charger, not a USB port, and leave it for 20–30 minutes without pressing anything. Most BMS circuits on this platform will accept a trickle current from the charge IC at this point and unlock once the cell climbs back above 2.8V.