{"product_id":"redmi-note-9-pro-5g-replacement-battery-385v-4600mah-li-polymer","title":"Redmi Note 9 Pro 5G Replacement Battery BM4W 3.85V 4600mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eRedmi Note 9 Pro 5G (M2007J17C) — 3.85V Li-Polymer Replacement Battery (BM4W)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 3.85V, 4600mAh Li-Polymer replacement battery for the Xiaomi Redmi Note 9 Pro 5G (model M2007J17C). It carries OEM part number BM4W and fits directly into the original battery bay. It restores capacity lost after normal cell degradation without requiring a new device.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eNote 9 Pro 5G and M2007J17C fitment:\u003c\/strong\u003e\n    Both model identifiers reference the same hardware revision — same 3.85V power rail, same BM4W connector pinout, and the same fuel gauge IC expecting a Li-Polymer cell discharge curve. One battery covers both.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We ran this cell through the BM4W charge cycle on a Note 9 Pro 5G unit. The BMS accepted charge handshake on the first connection, cell voltage stabilised at 4.38V at full charge, and the fuel gauge IC reached calibration after one full discharge-charge cycle.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFirst cycle after installation:\u003c\/strong\u003e\n    Disable fast charging for the first complete discharge-charge cycle. The fuel gauge IC calibrates its coulomb counter against the new cell's discharge curve on that first pass — running fast charge into an uncalibrated cell can offset the percentage readings for weeks.\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 BM4W cell\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThis happens when the fuel gauge IC still holds calibration data from the old, degraded cell. The new cell hits a voltage cliff under 5G modem or display load that the IC doesn't anticipate from the old curve. The phone cuts power before the percentage reading reaches zero. One full manual discharge to automatic shutdown — without fast charge — followed by a full charge resets the coulomb counter and eliminates the premature cutoff.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eOS reporting wrong battery percentage after cell swap\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThe percentage shown on screen comes from the fuel gauge IC, not a direct voltage reading. After a cell swap, the IC is still mapping the new cell's capacity against the old discharge curve stored in memory. This causes the display to jump, plateau, or report full charge at a lower true voltage. Let the phone complete one uninterrupted discharge down to auto-shutdown, then charge to 100% without interruption — the IC rewrites its internal model and percentage accuracy returns.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43391892357210,"sku":"BWCS-MUT100SL-1","price":31.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43391892389978,"sku":"BWCS-MUT100SL-2","price":36.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43391892422746,"sku":"BWCS-MUT100SL-3","price":39.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-MUT100SL-1.webp?v=1779142560","url":"https:\/\/batteryweb.com\/products\/redmi-note-9-pro-5g-replacement-battery-385v-4600mah-li-polymer","provider":"BatteryWeb","version":"1.0","type":"link"}