WizarPOS Wizar Q2 Replacement Battery WHB02-2600 7.4V

WizarPOS Wizar Q2 — 7.4V Li-ion Replacement Battery (WHB02-2600)

This 7.4V 2600mAh Li-ion battery replaces the WizarPOS WHB02-2600 in the Wizar Q2 handheld payment terminal. It uses the 6-pin connector required by the Q2's BMS communication line. Capacity is 2600mAh (19.24Wh) — matching the original cell specification from the product data.

• Wizar Q2 connector and BMS compatibility: The Q2 uses a 6-pin battery interface, not the simpler 2- or 3-pin found on generic POS hardware. The extra pins carry BMS communication signals that the terminal uses for charge state reporting and thermal monitoring. A battery without the correct pin-out causes the terminal to reject the pack entirely.
• Bench tested on actual hardware: We ran this pack through the Q2's full boot sequence and simulated transaction load including display, wireless, and printer draw. The BMS held the voltage rail steady through multiple receipt print cycles without triggering an overcurrent cutoff.
• First deployment prep for the Wizar Q2: After installing the battery, complete one full transaction cycle — including a printed receipt — before deploying in a live environment. The Q2 maps battery capacity during normal operation and needs at least one complete power cycle to calibrate the charge indicator accurately.

Terminal not completing PCI boot sequence after battery swap

The Q2 runs a PCI-compliant security check on every boot. If the BMS handshake hasn't been accepted yet, the terminal can stall or loop before reaching the home screen. This happens because the terminal hasn't logged a completed charge-discharge cycle with the new cell. Plug the terminal into its charging cradle, let it reach full charge, then power it on and complete one transaction. That sequence finalises the BMS handshake and clears the boot stall.

Wizar Q2 not powering on after sitting unused in a drawer

Li-ion cells self-discharge at roughly 2–3% per month. Left unused for several months, the Q2's battery can drop below 2.5V per cell — the threshold where the BMS locks the pack to prevent damage. The terminal shows no response because the BMS is blocking output, not because the cell is dead. Connect the terminal to the charging cradle and leave it for at least 90 minutes without pressing the power button; the charger applies a trickle current that brings the cell above the 3.0V recovery threshold before the BMS re-enables normal output.