{"product_id":"bbk-vivo-y50-replacement-battery-385v-4800mah-li-polymer","title":"BBK VIVO Y50 Replacement Battery 3.85V 4800mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eBBK Vivo Y50 \/ 1935 — 3.85V Li-Polymer Replacement Battery\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 3.85V, 4800mAh Li-Polymer replacement battery for the Vivo Y50 (model 1935). It replaces a degraded or failed original cell and restores power to the device's processor, display, and wireless radios. Dimensions are 88.10 × 63.55 × 4.85mm — confirm your existing cell matches before fitting.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eVivo Y50 \/ 1935 compatibility:\u003c\/strong\u003e\n    Both the Y50 and its internal board designation 1935 share the same battery bay dimensions, connector pinout, and BMS handshake protocol — one cell fits both references 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 a Y50 unit. The BMS accepted charge current without fault flags, and the protection circuit tripped correctly at low-voltage threshold — no thermal runaway events across the test run.\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-charge cycle at standard current. This lets the fuel gauge IC map the new cell's discharge curve before the coulomb counter starts reporting to the OS — skipping this step causes erratic percentage readings in the first few days.\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 Y50 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 the IC wasn't expecting, it interprets remaining capacity incorrectly. Under high-draw moments — mobile data, screen at full brightness, GPS active — the actual cell voltage drops faster than the reported percentage suggests. The fix is one full discharge to auto-off followed by a full uninterrupted charge, which forces the coulomb counter to resync to the new cell's actual voltage floor.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eUSB-PD or Vivo FlashCharge not activating on the replacement cell's first cycle\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eFast charging protocols on the Y50 require a handshake between the charge IC and the battery's BMS before elevated current is allowed. On a fresh cell, the BMS often defaults to slow-charge mode on the first cycle as a protection measure — this is normal behaviour, not a fault. Plug into the original Vivo charger and cable, not a third-party adapter, and let the first cycle complete at standard rate. Fast charging typically activates from the second cycle onward once the BMS clears its initial check.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43391946653786,"sku":"BWCS-BKY500SL-1","price":30.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43391946686554,"sku":"BWCS-BKY500SL-2","price":34.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43391946719322,"sku":"BWCS-BKY500SL-3","price":37.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-BKY500SL-1.webp?v=1779142719","url":"https:\/\/batteryweb.com\/products\/bbk-vivo-y50-replacement-battery-385v-4800mah-li-polymer","provider":"BatteryWeb","version":"1.0","type":"link"}