{"product_id":"bbk-vivo-s7-replacement-battery-37v-1200mah-li-ion","title":"BBK VIVO S7 Replacement Battery 3.7V 1200mAh BK-B-49","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eBBK VIVO S7 \/ E1T \/ Y3t Series — 3.7V Li-ion Replacement Battery (BK-B-49)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 3.7V, 1200mAh Li-ion cell for the BBK VIVO S7, VIVO S7t, VIVO E1T, and VIVO Y3t smartphones. It replaces OEM parts BK-B-49 and BK-B-42. Dimensions are 63.95 × 43.41 × 4.54mm — measure your original before fitting.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eVIVO S7 and E1T platform fit:\u003c\/strong\u003e\n    These models share the same battery bay dimensions, connector pinout, and BMS handshake protocol. One cell covers all listed variants 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 charge and discharge on VIVO hardware and confirmed BMS communication, thermal cutoff response, and charge termination voltage at 4.2V behaved within spec.\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 full discharge-charge cycle. This lets the fuel gauge IC map the new cell's discharge curve before high-current charging is applied to an uncalibrated cell.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eSudden shutdown at 20–30% on the VIVO S7 after a cell swap\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eA new cell has a different internal resistance profile than the aged cell the fuel gauge IC was calibrated against. Under high-draw loads — active modem, screen at full brightness, GPS — the cell voltage drops faster than the gauge predicts. The phone's protection circuit reads a voltage cliff and cuts power before the displayed percentage reaches zero. One full discharge-to-shutdown followed by an uninterrupted charge to 100% forces the coulomb counter to resync to the new cell curve and usually resolves this within two cycles.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eVIVO S7 not powering on after the replacement cell sat in storage\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eLi-ion cells self-discharge during storage. If the cell voltage drops below 2.5V, the BMS enters lockout mode and blocks current flow to protect the cell from damage. Plugging in a charger won't start a normal charge cycle — the BMS needs a low-current trickle to recover. Connect the phone to a wall adapter rated at 5V and leave it for 15–20 minutes without pressing the power button; the charge IC will apply a recovery current that brings the cell above the BMS re-enable threshold, typically around 2.9V.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43404312019034,"sku":"BWCS-BKV309SL-1","price":28.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43404312051802,"sku":"BWCS-BKV309SL-2","price":32.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43404312084570,"sku":"BWCS-BKV309SL-3","price":34.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-BKV309SL-1.webp?v=1779369679","url":"https:\/\/batteryweb.com\/products\/bbk-vivo-s7-replacement-battery-37v-1200mah-li-ion","provider":"BatteryWeb","version":"1.0","type":"link"}