{"product_id":"amazfit-a1929-replacement-battery-385v-270mah-li-polymer","title":"Amazfit A1929 Replacement Battery 3.85V 270mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eAmazfit Stratos 3 \/ A1929 — 3.85V Li-Polymer Replacement Battery (PL322728H)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 270mAh (1.04Wh) 3.85V lithium-polymer cell built to the PL322728H specification. It fits the Amazfit A1929 and Stratos 3 smartwatch platforms. Replace the original cell when the watch no longer holds a charge across a full day of use.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eA1929 and Stratos 3 compatibility:\u003c\/strong\u003e\n    Both models run the same 3.85V power rail, share the PL322728H cell footprint (27.80 × 22.90 × 3.40mm), and use an identical connector and BMS handshake — a single cell spec 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 charge and discharge cycles on the Stratos 3 platform. The onboard BMS accepted the cell without fault flags, and the fuel gauge IC registered correctly after a full charge cycle from near-zero.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003ePost-swap charge protocol for the Stratos 3:\u003c\/strong\u003e\n    Place the watch on its magnetic charger immediately after fitting this cell and charge to 100% before first use. The fuel gauge IC on this platform loses its voltage reference during a cell swap and cannot recalibrate without a complete 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 Stratos 3 fuel gauge reads incorrectly after a cell swap\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThe Stratos 3 uses a coulomb-counting fuel gauge IC that tracks charge state relative to a stored reference voltage. Removing the cell wipes that reference. When a new cell is fitted at partial charge, the IC has no baseline, so it reports an arbitrary percentage — often 0% or a frozen value. A full charge cycle from near-zero writes a new reference and restores accurate reporting. Until that cycle completes, the displayed percentage is not reliable.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eNew battery draining in one day instead of the expected multi-day window\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eOn the Stratos 3, continuous heart rate monitoring and always-on display mode together draw significantly more current than basic timekeeping. If both are active, a 270mAh cell will deplete far faster than the rated multi-day figure. Check the watch settings and disable continuous HR polling — switching to interval-based sampling (every 5 minutes) measurably reduces draw. GPS activity logging also pulls sustained current; disable background GPS if the watch is not actively recording a session.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43416149459034,"sku":"BWCS-AMT929SH-1","price":30.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43416149491802,"sku":"BWCS-AMT929SH-2","price":35.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43416149524570,"sku":"BWCS-AMT929SH-3","price":39.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-AMT929SH_1.webp?v=1779760467","url":"https:\/\/batteryweb.com\/products\/amazfit-a1929-replacement-battery-385v-270mah-li-polymer","provider":"BatteryWeb","version":"1.0","type":"link"}