{"product_id":"bbk-vivo-x27-replacement-battery-385v-3900mah-li-polymer","title":"B-G5 BBK VIVO X27 Compatible Battery 3.85V 3900mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eBBK Vivo X27 \/ X27A (V1829A, V1829) — 3.85V Li-Polymer Replacement Battery (B-G5)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThe B-G5 is the OEM-matched Li-Polymer cell for the Vivo X27, X27A, V1829A, and V1829 smartphones. It runs at 3.85V with a 3900mAh (15.02Wh) capacity. If your X27 no longer holds a charge, shuts down unexpectedly, or won't power on, this cell replaces the degraded unit directly.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eV1829 \/ V1829A platform fit:\u003c\/strong\u003e\n    The X27 and X27A share the V1829 board revision, which means the same BMS handshake protocol and connector pinout. Both models accept the B-G5 without modification to the flex cable or charge IC configuration.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We cycled this cell on a V1829A unit and confirmed the BMS accepted charge on the first connection, passed overvoltage and overcurrent cutoff checks, and reported cell chemistry correctly to the OS fuel gauge IC.\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 at standard rate. This lets the fuel gauge IC recalibrate its coulomb counter against the new cell's discharge curve before high-current charging pushes load into 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 X27 after a cell swap\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThe X27 fuel gauge IC stores a learned discharge curve from the old, degraded cell. After a swap, that stored curve no longer matches the new cell's voltage-to-capacity relationship. Under modem or display load, the phone samples cell voltage, sees it drop below the threshold predicted by the old curve, and triggers an emergency shutdown — even though real capacity remains. One full slow-discharge cycle forces the coulomb counter to relearn the new cell's profile and eliminates the false cutoff.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eUSB fast charging not activating after replacement on the X27\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eVivo's proprietary fast charge protocol requires the charge IC to confirm cell impedance is within an acceptable range before switching into high-current mode. A freshly installed cell with a full formation charge may present a slightly different impedance signature on the first cycle, causing the charge IC to fall back to standard 5V\/1A. This is not a fault in the replacement cell. Complete one full standard charge cycle first — impedance normalises, and fast charge activates automatically on the next connection without any manual step.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43392009732186,"sku":"BWCS-BYX270SL-1","price":25.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43392009764954,"sku":"BWCS-BYX270SL-2","price":28.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43392009797722,"sku":"BWCS-BYX270SL-3","price":31.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-BYX270SL-1.webp?v=1779142903","url":"https:\/\/batteryweb.com\/products\/bbk-vivo-x27-replacement-battery-385v-3900mah-li-polymer","provider":"BatteryWeb","version":"1.0","type":"link"}