{"product_id":"samsung-galaxy-m11-replacement-battery-385v-4900mah-li-polymer","title":"Samsung Galaxy M11 HQ-S71 Replacement Battery 3.85V 4900mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eSamsung Galaxy M11 — 3.85V Li-Polymer Replacement Battery (HQ-S71)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 3.85V, 4900mAh lithium-polymer replacement battery for the Samsung Galaxy M11 (SM-M115F\/DS). It carries OEM part numbers HQ-S71 and GH81-18734A and fits the M11 2020 variant. The cell slots into the same physical bay and connects to the same power management IC as the original unit.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eGalaxy M11 and SM-M115 series fit:\u003c\/strong\u003e\n    All SM-M115 variants share the same 3.85V power rail, connector pinout, and BMS handshake protocol. One replacement cell covers the full model range without adapter or modification.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We ran this cell through the Galaxy M11's charge IC and confirmed the BMS accepted the handshake, passed thermal checks, and held voltage under display and modem load without triggering a protection cutoff.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFuel gauge recalibration on first use:\u003c\/strong\u003e\n    After installing this cell, disable fast charging and run one full discharge-to-charge cycle at standard rate. This lets the fuel gauge IC map its coulomb counter against the new cell's discharge curve before high-current charging introduces error into an uncalibrated state.\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 Galaxy M11 after a cell swap\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eThis happens because the fuel gauge IC is still using the discharge curve it learned from the old, degraded cell. A new cell holds a steeper voltage cliff at the lower end of its range. When the modem fires a high-power transmission or the display peaks brightness, the cell voltage drops sharply — the IC reads this as a critically low state and triggers a shutdown before the percentage gauge catches up. One complete slow-charge cycle recalibrates the coulomb counter to the new cell's actual curve and eliminates the early cutoff.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eUSB fast charge not activating on the first cycle after replacement\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eOn the first connection after a cell swap, the charge IC runs a brief BMS authentication check before enabling the higher voltage negotiation required for fast charging. If the cell's state-of-charge is below roughly 3.6V per cell, the IC defaults to trickle mode and will not step up to fast charge until a baseline voltage is reached. Plug into a standard 5V charger first and let the phone reach around 15% charge. After that point, fast charging protocols re-engage normally on subsequent connections.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43391984369754,"sku":"BWCS-SMM115SL-1","price":30.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43391984402522,"sku":"BWCS-SMM115SL-2","price":35.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43391984435290,"sku":"BWCS-SMM115SL-3","price":38.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-SMM115SL-1.webp?v=1779142738","url":"https:\/\/batteryweb.com\/products\/samsung-galaxy-m11-replacement-battery-385v-4900mah-li-polymer","provider":"BatteryWeb","version":"1.0","type":"link"}