{"product_id":"vivo-y19-2019-replacement-battery-385v-4950mah-li-polymer","title":"Vivo Y19 2019 B-H9 Replacement Battery 3.85V 4950mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eVivo Y19 2019 \/ V1934 \/ U3 Series — 3.85V Li-Polymer Replacement Battery (B-H9)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 3.85V, 4950mAh lithium-polymer replacement cell for the Vivo Y19 2019 and its variants, including the V1934, U3, and U3x. It replaces the OEM B-H9 cell when the original has degraded through repeated charge cycles and can no longer hold adequate charge for daily use. Capacity figure is 19.06Wh at rated voltage.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eY19 2019 \/ V1934 \/ U3 \/ U3x platform fit:\u003c\/strong\u003e\n    These models share the same battery bay geometry, connector pinout, and BMS communication protocol — all running the same 3.85V nominal rail with identical flex cable routing. A single cell covers the full variant group.\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 the Y19 platform and monitored BMS handshake, charge acceptance, and cutoff behaviour. The protection circuit engaged correctly at both high-state and low-state voltage thresholds with no anomalous trips.\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 the charge IC pushes high current 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 replacement cell\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThis happens because the fuel gauge IC is still running the discharge curve it learned from the old, degraded cell. The new cell has a steeper voltage drop under modem or display load near that state-of-charge window, and the IC misreads remaining capacity. The phone shuts down before the percentage reaches zero. Run one full discharge cycle — down to automatic power-off — followed by an uninterrupted full charge. After that single cycle, the coulomb counter recalibrates against the new cell and the reported percentage aligns with actual voltage.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eUSB fast charge not activating after cell replacement\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eOn the first charge cycle after installation, the charge IC on the Y19 platform sometimes refuses to negotiate the proprietary fast-charge protocol because the BMS on the new cell has not yet completed its initialisation handshake. The phone charges slowly or not at all on a fast-charge adapter. Use a standard 5V charger for the first full cycle. After one complete charge, reconnect the fast-charge adapter — the BMS handshake completes and the protocol negotiation proceeds at the correct voltage step.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43391994593370,"sku":"BWCS-BKV193SL-1","price":26.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43391994626138,"sku":"BWCS-BKV193SL-2","price":29.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43391994658906,"sku":"BWCS-BKV193SL-3","price":32.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-BKV193SL-1.webp?v=1779142762","url":"https:\/\/batteryweb.com\/products\/vivo-y19-2019-replacement-battery-385v-4950mah-li-polymer","provider":"BatteryWeb","version":"1.0","type":"link"}