Zebra QLn220 Replacement Battery 7.4V 2600mAh AT16004

Zebra QLn220 / QLn320 Series — 7.4V Li-ion Replacement Battery (AT16004)

This 7.4V, 2600mAh Li-ion battery replaces the OEM pack in the Zebra QLn220, QLn220HC, and QLn320 portable thermal printers. It slots directly into the battery bay and communicates with the printer's BMS using the same protocol as the factory cell. Voltage and capacity match OEM spec — AT16004 cross-references confirmed against BTRY-MPP-34MA1-01 and P1031365 variants.

• QLn220 and QLn320 platform compatibility: Both models share the same 7.4V battery bay, connector pinout, and BMS handshake protocol. The same cell powers both the standard QLn220 and the cold-storage QLn220HC variant, which runs the same voltage rail despite the extended thermal range of the device.
• Bench tested on actual hardware: We ran this battery in a QLn220 unit and confirmed the BMS accepted the cell without error flags. Print motor current draw peaked at initial feed and the BMS held voltage without triggering an undervoltage cutoff during multi-label burst sequences.
• First-deployment print sequence: After installing a new cell, charge to full, then print at least five test labels before putting the unit into a live shift. The paper feed motor draws a current spike on first engagement — running a short print sequence lets the BMS record the correct load profile for the new cell before field use.

Bluetooth dropping mid-job on the QLn220

The QLn220's Bluetooth radio and print motor share power from the same 7.4V cell. When battery voltage sags below roughly 6.8V under motor load, the radio module loses stable power and drops the connection before the print job completes. This happens most often during burst printing — multiple labels back-to-back — because motor demand spikes repeatedly. If the printer reconnects automatically once the motor stops, low cell voltage is the cause, not a pairing or firmware issue. Charge the battery to full before a shift to keep voltage above the radio's stable operating threshold throughout the job.

Print head producing faded or uneven output on a charged battery

The QLn220's direct thermal head needs a stable voltage to hit the correct temperature across the full print width. If the battery cell has degraded internally, voltage droops under thermal head current draw even when the indicator shows a full charge — the result is faded lines or uneven darkness across the label. A healthy cell should hold above 7.0V under thermal head load; anything lower means the cell can no longer deliver rated current. Replace the battery and run a self-test print (hold the feed button during power-on) to confirm clean, consistent output before deployment.