{"product_id":"vodafone-702nk-replacement-battery-37v-1200mah-li-ion","title":"Vodafone 702NK Replacement Battery NKBF01 3.7V 1200mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eVodafone 702NK Series — 3.7V Li-ion Replacement Battery (NKBF01)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 3.7V, 1200mAh Li-ion cell built to replace the original NKBF01 battery in the Vodafone 702NK, 702NKII, and V804NK smartphones. It matches the OEM voltage, connector, and physical footprint at 53.00 × 33.90 × 5.70mm. Swap it when the original cell can no longer hold a usable charge.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003e702NK, 702NKII, and V804NK compatibility:\u003c\/strong\u003e\n    All three models share the same battery bay dimensions, 3.7V nominal rail, and NKBF01 connector pinout. The BMS handshake across this device family is identical, so one cell covers all three without modification.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We cycled this cell through full charge and load discharge on the 702NK platform. The BMS accepted the cell immediately, charge termination triggered correctly at 4.2V, and low-voltage cutoff engaged at the expected floor without tripping a fault state.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFuel gauge recalibration on first use:\u003c\/strong\u003e\n    On first use after installation, disable fast charging and run one complete discharge-to-charge cycle. This lets the fuel gauge IC map the new cell's discharge curve before it begins reporting accurate percentages to the OS.\n    \u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eWhy the 702NK reports wrong battery percentage after a cell swap\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThe 702NK uses a fuel gauge IC that learns the cell's discharge curve over time. When you fit a new cell, the IC is still calibrated to the old, degraded cell's curve. This mismatch causes the OS to display inflated or deflated percentages until the IC relearns. Run one full discharge from 100% to automatic shutdown, then charge uninterrupted to 100%. After that single cycle, the fuel gauge IC recalibrates and percentage readings stabilise.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eSudden shutdown at 20–30% on the replacement cell\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThis happens when the fuel gauge IC has not yet recalibrated and the displayed percentage does not match actual cell voltage. Under modem or screen load, the cell voltage drops sharply at a point the OS thinks is still safe — the BMS hits its undervoltage cutoff and kills the phone before the display reaches zero. It is not a faulty cell. Charge the phone fully, then run one uninterrupted discharge cycle. Once the coulomb counter has tracked a full cycle, the cutoff point and the displayed percentage align correctly.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43405031702618,"sku":"BWCS-NK5CHL-1","price":40.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43405031735386,"sku":"BWCS-NK5CHL-2","price":47.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43405031768154,"sku":"BWCS-NK5CHL-3","price":52.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-NK5CHL-1.webp?v=1779369842","url":"https:\/\/batteryweb.com\/products\/vodafone-702nk-replacement-battery-37v-1200mah-li-ion","provider":"BatteryWeb","version":"1.0","type":"link"}