{"product_id":"o2-xda-serra-replacement-battery-37v-2400mah-li-ion","title":"O2 Xda Serra Replacement Battery 3.7V 2400mAh DIAM171","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eO2 Xda Serra \/ XDA Diamond Pro — 3.7V Li-ion Replacement Battery (DIAM171)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 3.7V 2400mAh Li-ion battery for the O2 Xda Serra and XDA Diamond Pro smartphones. It replaces OEM part numbers DIAM171, 35H00111-08M, and 35H00111-06M. At 8.88Wh, it matches the original cell specification inside these Windows Mobile handsets.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eXda Serra and XDA Diamond Pro compatibility:\u003c\/strong\u003e\n    Both devices share the same battery bay dimensions, connector pinout, and BMS handshake protocol — confirmed against the DIAM171 reference. The 41.96 × 40.82 × 15.75mm cell fits the cavity without modification.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We cycled this cell through full charge and discharge on the Xda Serra. The BMS communicated correctly with the charge IC, current tapered properly at full voltage, and no thermal event occurred during the charge phase.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFuel gauge recalibration after installation:\u003c\/strong\u003e\n    The Xda Serra's fuel gauge IC holds a discharge curve calibrated to the worn original cell. On first use, run the battery down to auto-shutdown and charge uninterrupted to 100% — this lets the coulomb counter reset its baseline against the new cell's actual capacity.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eWhy the Xda Serra reports wrong battery percentage after a cell swap\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThe fuel gauge IC on the Xda Serra stores a learned discharge curve from the old cell. A new 2400mAh cell has a different internal resistance and discharge profile, so the IC's stored model no longer matches reality. Until the counter resets, the percentage reading will drift — often reading 100% for an extended period, then dropping sharply. One full uninterrupted discharge-to-charge cycle corrects the calibration.\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 is a voltage cliff problem, not a capacity fault. When the modem, screen backlight, or GPS fires simultaneously, instantaneous current draw pulls the cell voltage below the BMS cutoff threshold — even if the state-of-charge still reads above 20%. The BMS trips as a protection response, not a malfunction. After the fuel gauge completes one full calibration cycle, the percentage display will align with the actual voltage curve and the premature shutdowns typically stop.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43405196361818,"sku":"BWCS-HDP100XL-1","price":28.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43405196394586,"sku":"BWCS-HDP100XL-2","price":32.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43405196427354,"sku":"BWCS-HDP100XL-3","price":35.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-HDP100XL-1.webp?v=1779370333","url":"https:\/\/batteryweb.com\/products\/o2-xda-serra-replacement-battery-37v-2400mah-li-ion","provider":"BatteryWeb","version":"1.0","type":"link"}