About this replacement
INT RASTER Memory Backup — 3.7V Li-Polymer Replacement Battery (P-2209)
This is a 3.7V, 250mAh lithium-polymer replacement battery for the INT RASTER Memory Backup unit. It fits devices using OEM part number P-2209. The battery holds power to the terminal's memory when main supply drops, protecting transaction data and system settings during outages.
- Memory Backup P-2209 platform fit: This cell matches the voltage rail, connector footprint, and BMS handshake requirements of the P-2209 backup circuit. The backup circuit uses a dedicated charge path separate from the main power rail, and the replacement cell must match the 3.7V nominal charge profile to avoid triggering a low-cell fault on the BMS.
- Bench tested on actual hardware: We cycled the cell through simulated main-power interruptions and confirmed the BMS accepted the new cell without triggering a fault flag. Charge termination occurred cleanly at 4.2V with no top-off errors logged.
- Post-swap transaction cycle: After fitting this battery, run one complete power cycle before putting the terminal back into service. The terminal maps backup capacity during normal operation and needs at least one full boot-charge sequence to calibrate the charge indicator correctly.
Why the Memory Backup terminal reboots mid-transaction after a battery swap
A mid-transaction reboot almost always points to the BMS tripping on an overcurrent event during the printer motor or wireless module draw spike. On first installation, the BMS has no learned capacity baseline, so its overcurrent threshold is at its most conservative. The terminal interprets the BMS trip as a main power fault and initiates a cold reboot. Running two or three complete transaction cycles lets the BMS establish a current draw profile and widens the trip threshold to match normal operating load.
Terminal not powering on after sitting unused in a drawer
A Li-Polymer cell left without charge for several months can fall below the BMS recovery threshold — typically around 2.5V — and the BMS will block charge input as a safety measure. The terminal shows no charge indicator and appears completely dead. Connect the terminal to its original charger and leave it for 30 to 60 minutes without interruption; some chargers apply a trickle pre-charge below 2.8V to recover the cell before switching to normal CC/CV charge. If the charge indicator does not appear after 60 minutes, check that the charger output is present at the port — a confirmed 5V input at the connector confirms the cell itself is below recovery threshold.