NET10 Z289L Replacement Battery 3.7V 3400mAh Li-ion

NET10 Z289L / SRQ-Z289L — 3.7V Li-ion Replacement Battery

This 3.7V 3400mAh Li-ion battery fits the NET10 Z289L and SRQ-Z289L portable WiFi hotspot. It replaces the factory cell when the original no longer holds a charge or fails to boot the unit. Capacity is 3400mAh (12.58Wh) — taken from product data, not estimated.

• Z289L and SRQ-Z289L compatibility: Both variants share the same physical cell format, connector pinout, and BMS voltage thresholds. A single replacement covers either unit — no hardware differences affect fit or function.
• Bench tested on actual hardware: We ran this cell under combined modem and WiFi radio load at maximum connected devices. The BMS held the 3.7V nominal rail without triggering low-voltage cutoff during sustained draw.
• Ventilation during extended sessions: Keep the hotspot flat on a hard surface with clearance on all sides when running long sessions. The cellular radio ramps to full output power when connected devices are far away — that heat builds inside the unit and stresses the cell. Soft surfaces like bedding or a couch cushion trap heat directly against the battery.

Why the Z289L drops connections mid-session under maximum device load

The Z289L runs two power-hungry systems simultaneously — the LTE modem and the WiFi radio. When all connected device slots are active, combined current draw spikes sharply. If the battery cell has degraded internal resistance, voltage sags below the threshold the BMS protects, and the unit resets or drops the WiFi broadcast. A fresh cell with lower internal resistance holds the rail steady through those spikes. If drop-outs stop after fitting this battery, the old cell's resistance was the cause.

Z289L not powering on after sitting unused for weeks

Li-ion cells self-discharge during storage. If the Z289L sat unpowered long enough, the cell voltage can fall below the minimum boot threshold — typically around 3.0V — and the unit will not respond to the power button. Connect the hotspot to the charger for at least 20 minutes before attempting to power on. If the charge indicator light does not activate within two minutes of connecting the cable, the original cell has likely dropped below the BMS recovery floor, and replacement is the correct next step.