{"product_id":"xiaomi-redmi-note-5-replacement-battery-385v-3900mah-li-polymer","title":"Xiaomi Redmi Note 5 Compatible Battery BN45 3.85V 3900mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eXiaomi Redmi Note 5 — 3.85V Li-Polymer Replacement Battery (BN45)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 3.85V, 3900mAh lithium-polymer cell built to the BN45 specification. It fits the Redmi Note 5, Redmi Note 5 Standard Edition Global, and the Dual SIM TD-LTE variant, among other MEG7S-series models. Swap it when the original cell can no longer hold enough charge to get through a normal day.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eRedmi Note 5 series fit:\u003c\/strong\u003e\n    All listed variants share the same physical footprint, connector pinout, and BMS handshake protocol — the fuel gauge IC on every board in this family reads the same cell chemistry signature, so no firmware flags are triggered on swap.\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 load on a Redmi Note 5 board. The BMS accepted the cell without lockout, the charge IC ramped current correctly, and the coulomb counter began tracking within one full discharge cycle.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFirst-cycle fuel gauge recalibration:\u003c\/strong\u003e\n    After installation, disable fast charging and run one full discharge down to auto-shutdown, then charge slowly to 100%. This lets the fuel gauge IC map its coulomb counter against the new cell's actual discharge curve before high-current charging begins on 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\"\u003eWhy the Redmi Note 5 reports wrong battery percentage after a cell swap\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eThe fuel gauge IC stores a learned discharge curve from the original cell. When a new cell goes in, that stored curve no longer matches the actual voltage-to-capacity relationship of the replacement. The IC reads voltage correctly but maps it to the wrong capacity figure, so the percentage display drifts. One full discharge-to-shutdown followed by a slow charge to 100% forces the coulomb counter to re-anchor to the new cell's curve.\u003c\/p\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 when the cell voltage drops sharply under combined modem and display load — a voltage cliff the fuel gauge did not predict because its curve was calibrated to the old cell. The phone's protection circuit reads the drop as an imminent under-voltage event and shuts down before the displayed percentage reaches zero. Run the recalibration cycle first: one slow full discharge, then charge uninterrupted to 100%. If shutdowns continue after two full cycles, check that the cell resting voltage reads above 3.7V with a multimeter before reinstalling.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43392023887962,"sku":"BWCS-MUM560SL-1","price":25.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43392023920730,"sku":"BWCS-MUM560SL-2","price":28.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43392023953498,"sku":"BWCS-MUM560SL-3","price":31.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-MUM560SL-1.webp?v=1779142944","url":"https:\/\/batteryweb.com\/products\/xiaomi-redmi-note-5-replacement-battery-385v-3900mah-li-polymer","provider":"BatteryWeb","version":"1.0","type":"link"}