{"product_id":"nihon-kohden-cardiofax-g-ecg-2550-monitor-replacement-battery-144v-3500mah-ni-mh","title":"Nihon Kohden SB-201D Cardiofax G ECG-2550 14.4V Replacement Battery","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eNihon Kohden Cardiofax G ECG-2550 Monitor — 14.4V Ni-MH Replacement Battery (SB-201D)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis 14.4V, 3500mAh Ni-MH battery replaces the SB-201D in the Nihon Kohden Cardiofax G ECG-2550 electrocardiograph. It fits the ECG-2550 Monitor used in hospitals and diagnostic facilities for portable cardiac recording. Capacity is 3500mAh (50.4Wh), matching the original cell specification.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eECG-2550 platform fit:\u003c\/strong\u003e\n    The Cardiofax G ECG-2550 uses a fixed 14.4V Ni-MH architecture with BMS communication tied to the SB-201D part designation. The connector pinout and cell count are specific to this monitor line — no cross-compatibility with other Nihon Kohden ECG models.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We ran full charge-discharge cycles on the ECG-2550 platform and confirmed the BMS handshake completes correctly. The charge IC accepted the new cell without flagging a fault, and the protection circuit tripped at the correct low-voltage threshold during discharge.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003ePost-installation self-test cycle:\u003c\/strong\u003e\n    After fitting this battery, let the ECG-2550 complete its full power-on self-test without interruption. The device runs a BMS verification sequence at startup — cutting power during this sequence triggers a false battery fault that persists until the next full reboot.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eECG-2550 not completing boot sequence on a new battery\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThe ECG-2550 runs a firmware-level power check during boot that compares reported cell voltage against a stored OEM threshold. A new Ni-MH cell sitting at partial charge from shipping can read below that threshold, causing the boot sequence to stall or abort. This is not a faulty battery — it is the BMS rejecting an unverified cell. Charge the battery fully before the first power-on, then allow the device to boot without interruption.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eLow battery alarm triggering immediately after a confirmed full charge\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThis happens because the ECG-2550's charge IC uses internal resistance and voltage slope data to assess cell state — data it does not yet have for a new cell. Until the battery completes one full charge-discharge cycle, the BMS applies conservative thresholds that cause premature low-battery alerts. The cell is not defective. Run one complete cycle — full charge, then full discharge under normal device load — before relying on the battery indicator for clinical use. After that cycle, alarm behaviour normalises.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43381423046746,"sku":"BWCS-NK2550MD-1","price":101.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43381423079514,"sku":"BWCS-NK2550MD-2","price":119.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43381423112282,"sku":"BWCS-NK2550MD-3","price":132.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-NK2550MD-1.webp?v=1778900681","url":"https:\/\/batteryweb.com\/products\/nihon-kohden-cardiofax-g-ecg-2550-monitor-replacement-battery-144v-3500mah-ni-mh","provider":"BatteryWeb","version":"1.0","type":"link"}