{"product_id":"ntk-submarine-replacement-battery-12v-3800mah-ni-mh","title":"NTK Submarine Laptop Replacement Battery DR36 12V 3800mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eNTK Submarine — 12V Ni-MH Replacement Battery (DR36)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 12V, 3800mAh Ni-MH replacement battery for the NTK Submarine notebook. It fits the Submarine series and uses OEM part numbers DR36 and DR36S. Capacity matches the original cell at 45.6Wh — no modification required to install.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eNTK Submarine compatibility:\u003c\/strong\u003e\n    The DR36 and DR36S share the same 12V rail, physical connector, and BMS handshake as the original Submarine battery pack. Both part numbers refer to the same cell configuration, so either OEM reference confirms the correct fit.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We cycled this cell through charge and discharge under a controlled load. The BMS responded correctly at both low-voltage cutoff and full-charge termination — no false trips or runaway charge events observed.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFirst-cycle calibration on the Submarine:\u003c\/strong\u003e\n    After installing, run one full discharge to hibernate-cutoff, then charge uninterrupted to 100%. Ni-MH cells require this to let the fuel gauge IC reset its baseline against the new cell — skipping it causes the BIOS battery health warning to persist after the swap.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eWhy the Submarine's BIOS flags poor battery health after a cell swap\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThe Submarine stores battery health data in EEPROM on the original pack. When a new cell goes in, the BIOS reads stale data from its own records and reports poor health — not a fault with the replacement. Running the battery learn cycle (full discharge to cutoff, uninterrupted recharge to 100%) forces the BIOS to re-evaluate and overwrite that cached health state. Until the cycle completes, the health warning is expected and does not indicate a defective cell.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eSubmarine shutting down at 20–30% battery shown\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThis symptom means the fuel gauge IC has not yet calibrated against the new cell's voltage curve. The OS reads a percentage based on old calibration data, so the cell hits its actual low-voltage floor while the display still shows 20–30% remaining. The laptop shuts down because the cell voltage drops below the BMS cutoff threshold — not because the battery is faulty. Run two full discharge-to-cutoff and recharge cycles; by the third cycle the gauge IC re-maps the curve and the reported percentage aligns with real capacity.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43410856738906,"sku":"BWCS-DR36HB-1","price":89.99,"currency_code":"USD","in_stock":false},{"title":"Warranty 2 Year","offer_id":43410856771674,"sku":"BWCS-DR36HB-2","price":105.99,"currency_code":"USD","in_stock":false},{"title":"Warranty 3 Year","offer_id":43410856804442,"sku":"BWCS-DR36HB-3","price":118.99,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-DR36HB-big.webp?v=1779581376","url":"https:\/\/batteryweb.com\/products\/ntk-submarine-replacement-battery-12v-3800mah-ni-mh","provider":"BatteryWeb","version":"1.0","type":"link"}