{"product_id":"nihon-kohden-ems-1052-replacement-battery-144v-5500mah-li-ion","title":"Nihon Kohden SB-121V EMS-1052 Replacement Battery 14.4V","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eNihon Kohden EMS-1052 Defibrillator — 14.4V Li-ion Replacement Battery (SB-121V)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 14.4V, 5500mAh (79.2Wh) lithium-ion replacement battery for the Nihon Kohden EMS-1052 portable defibrillator\/monitor. It matches the OEM part number SB-121V and fits both the standard EMS-1052 and the EMS-1052 Defibrillator variant. The original battery losing capacity in a defibrillation device is a clinical risk — this replacement restores full operational capacity.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eEMS-1052 platform fit:\u003c\/strong\u003e\n    Both EMS-1052 variants share the same battery bay geometry, 14.4V voltage rail, and SB-121V connector pinout. The BMS handshake protocol is identical across the platform, so one battery SKU covers both configurations without modification.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We ran this cell through charge, discharge, and BMS communication cycles on the EMS-1052. The BMS authenticated correctly, cell balancing initiated on the first charge, and no fault codes were triggered at the device level.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003ePost-swap self-test cycle:\u003c\/strong\u003e\n    After fitting this battery, let the EMS-1052 complete its full power-on self-test without interruption. The device runs a BMS verification sequence at startup — cutting power during that window creates a false battery fault that persists until the next clean reboot, even though the battery itself is fine.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eCharge indicator not reaching 100% on the first charge after swap\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eThe EMS-1052 charge IC applies a conservative current limit when it first communicates with a new cell. This is intentional — the charge controller runs a capacity assessment pass before allowing a full top-up. On the first charge cycle, the indicator may plateau at 90–95% and stop climbing. Complete one full charge-discharge cycle, then recharge to 100%. After that initial learn cycle, the charge IC recalibrates its upper voltage threshold and the indicator reflects true full charge.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eEMS-1052 alarming low battery immediately after a confirmed full charge\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThis happens when the device's BMS compares the new cell's resting voltage against a threshold calibrated for a conditioned OEM cell. A fresh replacement cell sitting at nominal charge can read slightly below that threshold until the battery completes one full cycle. The alarm is a BMS mismatch — not a cell defect. Run one complete charge-to-discharge-to-charge cycle, then confirm the resting open-circuit voltage sits at or above 16.2V before returning the unit to service.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43381411414106,"sku":"BWCS-NKS105MD-1","price":480.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43381411446874,"sku":"BWCS-NKS105MD-2","price":574.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43381411479642,"sku":"BWCS-NKS105MD-3","price":644.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-NKS105MD-1.webp?v=1778900625","url":"https:\/\/batteryweb.com\/products\/nihon-kohden-ems-1052-replacement-battery-144v-5500mah-li-ion","provider":"BatteryWeb","version":"1.0","type":"link"}