{"product_id":"vivo-v2318a-replacement-battery-391v-5850mah-li-polymer","title":"Vivo BA45 V2318A Replacement Battery 3.91V 5850mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eVivo Y36 5G \/ Y36i 5G \/ Y28 — 3.91V Li-Polymer Replacement Battery (BA45)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is the BA45 lithium-polymer battery for the Vivo V2318A, Y28, Y36 5G, and Y36i 5G. It runs at 3.91V with a capacity of 5850mAh (22.87Wh). If your original cell is swelling, losing charge rapidly, or refusing to power the device, this is the direct cell replacement.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eV2318A \/ Y28 \/ Y36 5G \/ Y36i 5G platform fit:\u003c\/strong\u003e\n    These four models share the same battery bay dimensions, connector pinout, and BMS handshake protocol — all validated against the BA45 part number. Swapping between models on this platform does not require firmware changes.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We ran this cell through charge and discharge cycles on a Y36 5G unit. The BMS accepted the cell without error flags, charge current ramped normally through CC\/CV stages, and protection circuitry tripped correctly at the expected low-voltage cutoff threshold.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFuel gauge recalibration on first use:\u003c\/strong\u003e\n    After installation, disable fast charging and run one full discharge-to-charge cycle at standard current. This lets the fuel gauge IC map its coulomb counter against the new cell's discharge curve before high-current charging loads 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 Y36 5G after a cell swap\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThis happens because the fuel gauge IC still holds the discharge curve of the old, degraded cell. When the new cell hits a voltage point that mapped to 20–30% on the worn cell, the OS reads it as near-empty and triggers a protective shutdown. The phone still has usable charge — the gauge is just wrong. One complete discharge cycle down to automatic cutoff, followed by a full charge, forces the coulomb counter to resync to the new cell. After that cycle, percentage reporting stabilises.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eUSB-PD fast charge not activating on the first cycle after replacement\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eOn the first charge after a cell swap, Vivo's charge IC runs a brief cell-validation handshake before enabling the high-current fast charge path. If the BMS on the replacement cell hasn't completed that handshake, the charger falls back to standard 5V input. This is not a fault — it resolves after the first full charge cycle completes. Plug into the original Vivo charger for the first cycle; third-party chargers that negotiate voltage before the handshake finishes can extend the delay.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43391781109850,"sku":"BWCS-BYV280SL-1","price":43.99,"currency_code":"USD","in_stock":false},{"title":"Warranty 2 Year","offer_id":43391781142618,"sku":"BWCS-BYV280SL-2","price":51.99,"currency_code":"USD","in_stock":false},{"title":"Warranty 3 Year","offer_id":43391781175386,"sku":"BWCS-BYV280SL-3","price":56.99,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-BYV280SL-1.webp?v=1779141908","url":"https:\/\/batteryweb.com\/products\/vivo-v2318a-replacement-battery-391v-5850mah-li-polymer","provider":"BatteryWeb","version":"1.0","type":"link"}