About this replacement
ZTE Pocket WiFi 601ZT / 801ZT — 3.85V Li-Polymer Replacement Battery (Li3920T44P8h644348)
This is a 3.85V, 2000mAh (7.7Wh) Li-Polymer replacement battery for the ZTE Pocket WiFi 601ZT and 801ZT mobile hotspot devices. It matches the OEM part number Li3920T44P8h644348 and slots into the same battery compartment as the original. When your hotspot stops holding a charge or won't power on, this is the replacement cell.
- 601ZT and 801ZT compatibility: Both devices share the same battery footprint, connector pinout, and BMS communication protocol. The 63.40 × 42.60 × 4.50mm cell fits either unit without modification.
- Bench tested on actual hardware: We ran this cell through charge and discharge cycles on a 601ZT unit with four simultaneous connected clients. The BMS held stable voltage delivery under combined modem and WiFi radio load with no spurious cutoff events.
- Cellular signal and heat management: Keep the hotspot in a well-ventilated spot during extended sessions. When connected devices are far from the unit, the cellular radio runs at maximum output power — that sustained draw generates heat that accelerates cell wear over time.
Hotspot disconnecting clients mid-session on a new battery
A fresh cell can still trigger mid-session disconnects if the hotspot is at maximum client count in a weak signal area. The modem and WiFi radio pull current simultaneously at peak output, causing a brief voltage sag below the BMS protection threshold. The BMS interprets this as an undervoltage fault and cuts output, dropping all connected clients. Reducing the active client count to two or three, or moving closer to a cell tower, keeps the combined draw within the battery's sustained discharge rating.
601ZT won't power on after sitting unused for several weeks
Li-Polymer cells self-discharge in storage, and the 601ZT's standby current slowly drains the battery even when the unit is switched off. If the cell drops below roughly 3.0V, the BMS locks out discharge to prevent damage and the device appears completely dead. Connect the hotspot to a charger and leave it for at least 30 minutes before attempting to power it on — most BMS circuits re-initialise once the cell recovers above 3.2V. If the charge indicator light does not appear within five minutes of connecting the charger, disconnect and reconnect to prompt the BMS wake cycle.