About this replacement
Sunmi T5930 / V2 / V2 Pro — 7.6V Li-Polymer Replacement Battery (ZAP1522)
This 7.6V 2500mAh Li-Polymer battery replaces the ZAP1522 cell in the Sunmi T5930, V2, and V2 Pro payment terminals. All three models share the same battery bay, connector pinout, and BMS handshake protocol. Capacity is 2500mAh (19Wh) — exactly as shipped from the factory.
- T5930, V2, and V2 Pro compatibility: These terminals run on the same 7.6V power rail and use an identical physical connector and BMS communication line. Swapping between models does not require firmware changes — the charge IC recognises the cell by voltage profile alone.
- Bench tested on actual hardware: We cycled this battery through the T5930's charge IC and confirmed BMS handshake acceptance, correct cell voltage reporting, and stable draw during receipt printing — the highest single-event current spike in normal terminal operation.
- First deployment tip for POS environments: After installing this battery, complete one full transaction cycle — including a receipt print — before putting the terminal into live service. The T5930 maps battery capacity during normal operation and needs at least one complete power cycle to display the charge indicator accurately.
Why the T5930 reboots mid-transaction after a battery swap
The receipt printer motor draws a short but sharp current spike — sometimes exceeding 1.5A for a fraction of a second. If the BMS on a new cell has not yet completed its first full charge-discharge initialisation, it can trip an overcurrent cutoff at that spike and reboot the terminal. This is not a faulty battery. Running one complete transaction cycle, including a print, lets the BMS calibrate its overcurrent threshold correctly and prevents false trips during live use.
Terminal not powering on after sitting unused in storage
Li-Polymer cells self-discharge at roughly 2–3% per month. A terminal left in a drawer for several months can drop below the 6.0V recovery threshold the T5930's charge IC requires to begin a charge cycle. Plugging the terminal in at this point may show no response at all. Connect the terminal to its original charger and leave it for 30–45 minutes without pressing the power button — most charge ICs include a trickle-recovery mode that slowly raises the cell above 6.0V before switching to normal charge. Once the screen shows any charge indicator, the battery has cleared the recovery threshold.