About this replacement
ZTE Blade A2 Plus — 3.85V Li-Polymer Replacement Battery (Li3949T44P8h945754)
This is a 3.85V, 4900mAh (18.87Wh) Li-Polymer cell for the ZTE Blade A2 Plus and Blade A2 Plus Dual SIM TD-LTE (BV0720, BV0730). It replaces OEM part Li3949T44P8h945754 when the original cell no longer holds a usable charge. The battery powers the processor, display, modem, and all onboard functions.
- Blade A2 Plus and BV0720/BV0730 compatibility: These model variants share the same battery bay dimensions (92.20 × 56.50 × 5.30mm), connector pinout, and BMS handshake protocol — one cell covers all of them without modification.
- Bench tested on actual hardware: We cycled this cell through charge and discharge on the Blade A2 Plus platform and confirmed the BMS accepted the cell, completed a full charge without error flags, and held voltage through screen-on and modem-active loads.
- Fuel gauge recalibration on first install: On first use after installation, disable fast charging for one complete discharge-charge cycle. This lets the fuel gauge IC map the new cell's discharge curve before the charge IC pushes high current into an uncalibrated cell — preventing erratic percentage readings from the start.
Sudden shutdown at 20–30% on the Blade A2 Plus
The Blade A2 Plus shuts off abruptly at 20–30% remaining when the cell can no longer sustain voltage under modem or display load spikes. A degraded original cell may read 3.65V at rest but collapse below the BMS cutoff threshold — around 3.0V per cell — the moment current demand peaks. A fresh 4900mAh cell with lower internal resistance holds voltage through those transients. After fitting this replacement, run one full discharge-charge cycle before relying on the percentage readout.
USB fast charge not responding on the first cycle after cell replacement
After swapping the cell, some users find fast charging does not activate — the phone charges slowly or the fast-charge indicator never appears. This happens because the BMS on a fresh cell starts in a conservative trickle state until it completes one full charge cycle and handshakes with the charge IC. Force a full discharge down to auto-shutoff, then charge uninterrupted to 100% with the screen off. Fast charge should negotiate normally from the second cycle onward.