{"product_id":"samsung-sm-r880-replacement-battery-388v-240mah-li-polymer","title":"Samsung Galaxy Watch Active EB-BR880ABE Replacement Battery 3.88V 240mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eSamsung Galaxy Watch 4 40mm \/ SM-R880 — 3.88V Li-Polymer Replacement Battery (EB-BR880ABE)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis 3.88V, 240mAh Li-Polymer cell replaces the original battery in the Samsung Galaxy Watch 4 40mm, SM-R880, SM-R880N, and SM-R885. It restores power to the watch's display, heart rate sensor, activity tracking, and notification functions. Capacity is 240mAh (0.93Wh), matching the original cell specification.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eSM-R880 \/ SM-R885 platform fit:\u003c\/strong\u003e\n    These models share the same 3.88V cell format, connector pinout, and BMS communication protocol. The fuel gauge IC on all variants reads state-of-charge from the same register set, so this cell slots in without firmware conflict.\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 SM-R880 platform. The BMS accepted the new cell without triggering a protection cutoff, and the fuel gauge re-calibrated correctly after a full charge cycle from near-zero.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003ePost-swap charge requirement:\u003c\/strong\u003e\n    After fitting this cell, place the watch on its magnetic charger immediately and charge to 100% before use. The fuel gauge IC loses its state-of-charge reference during a cell swap and cannot set an accurate baseline without one full charge cycle from near-zero.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eWhy the SM-R880 fuel gauge reads incorrectly after a cell swap\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThe Galaxy Watch 4 uses a coulomb-counting fuel gauge IC that tracks charge by integrating current over time from a known reference point. When the original cell is removed, that reference is lost entirely. The IC does not automatically reset — it resumes counting from whatever value was stored in non-volatile memory. A full charge cycle from near-zero forces the IC to re-anchor its 100% and 0% endpoints against the new cell's actual capacity, correcting percentage readings across the full range.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eWatch not pairing to the Galaxy app after battery replacement\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eRemoving the battery during a swap terminates the active BLE session between the watch and the paired phone. The Galaxy Wearable app holds the previous session key and will not automatically re-establish a connection after power is restored. On the watch, go to Settings → General → Reset, then open the Galaxy Wearable app on the phone and select Add new device. Re-pairing takes under two minutes and restores all notification and health sync functions.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43416158175322,"sku":"BWCS-SMR880SH-1","price":22.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43416158208090,"sku":"BWCS-SMR880SH-2","price":25.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43416158240858,"sku":"BWCS-SMR880SH-3","price":28.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-SMR880SH-1.webp?v=1779760522","url":"https:\/\/batteryweb.com\/products\/samsung-sm-r880-replacement-battery-388v-240mah-li-polymer","provider":"BatteryWeb","version":"1.0","type":"link"}