{"product_id":"oneil-rp4-replacement-battery-74v-5200mah-li-ion","title":"ONeil RP4 Replacement Battery 7.4V 5200mAh 550053-000","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eONeil RP4 — 7.4V Li-ion Replacement Battery (550053-000)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis 7.4V 5200mAh Li-ion battery replaces the OEM 550053-000 cell in the ONeil RP4 mobile receipt printer. The RP4 is a portable thermal printer used in retail, delivery, and field service environments where continuous on-site printing is critical. Voltage and capacity match the original specification exactly.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eRP4 platform fit:\u003c\/strong\u003e\n    The RP4 battery bay uses a fixed connector pinout tied to a specific BMS handshake voltage. This cell matches that handshake, so the printer firmware recognises it as a valid power source without prompting a fault code.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We ran this cell through charge cycles on the RP4 platform and confirmed the BMS holds a stable output rail during paper feed motor engagement — the highest-draw moment in the print cycle.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFirst-deployment print sequence:\u003c\/strong\u003e\n    After installing, charge to full, then print five test receipts before putting the unit into service. The paper feed motor draws a brief current spike on each job; running a short sequence lets the BMS log the correct current profile for the new cell and prevents nuisance low-battery warnings during early use.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eWhy the RP4 stops printing after sitting unused for weeks\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eLi-ion cells self-discharge during storage. If the RP4 sits idle long enough, the cell voltage drops below the printer's minimum motor-drive threshold — typically around 6.0V for this platform — and the unit will power on but refuse to feed paper or fire the thermal head. The BMS interprets the low-cell state as a fault condition, not a dead battery. A full charge cycle before attempting a print job will bring the cell back into the working voltage window and clear the fault state.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eFaded or uneven print output on a charged battery\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eThe RP4's thermal print head requires a stable voltage to maintain consistent head temperature across the full receipt width. A degraded or partially discharged cell causes the voltage rail to sag mid-print, which drops head temperature and produces faded bands or incomplete characters. This is not a paper or head-calibration issue — it is a power delivery issue. Charge the battery fully and retest; if fading persists, check that the battery contacts in the bay are clean and seated flush, as resistance at the connector produces the same sag effect.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43415993090138,"sku":"BWCS-HPR400SL-1","price":56.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43415993122906,"sku":"BWCS-HPR400SL-2","price":66.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43415993155674,"sku":"BWCS-HPR400SL-3","price":73.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-HPR400SL-1.webp?v=1779758841","url":"https:\/\/batteryweb.com\/products\/oneil-rp4-replacement-battery-74v-5200mah-li-ion","provider":"BatteryWeb","version":"1.0","type":"link"}