{"product_id":"mwg-xda-iis-replacement-battery-37v-4200mah-li-ion","title":"MWG XDA IIS Replacement Battery 3.7V 4200mAh Li-ion","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eMWG XDA IIS — 3.7V Li-ion Replacement Battery (PH26B)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis 3.7V, 4200mAh Li-ion cell replaces the original battery in the MWG XDA IIS pocket PC phone. The XDA IIS is a Windows Mobile device from the mid-2000s, and original cells at this age have typically lost significant charge-holding capacity. This replacement restores full voltage delivery to the processor, radio module, and display.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eXDA IIS platform fit:\u003c\/strong\u003e\n    The XDA IIS shares its battery bay dimensions and connector pinout with a narrow group of HTC-platform Windows Mobile devices from this era. Voltage regulation on the board runs directly off the cell — no intermediate buck stage — so correct cell voltage matters at load, not just at rest.\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 XDA IIS platform and confirmed the BMS communicates correctly with the charge IC, holds cutoff at the expected low-voltage threshold, and does not trip under display and radio combined load.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFuel gauge recalibration on first use:\u003c\/strong\u003e\n    On first use after installation, disable any fast-charge accessory and run one complete discharge-charge cycle at standard current. This lets the fuel gauge IC map its coulomb counter against the new cell's actual discharge curve before reporting percentages to the OS.\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 XDA IIS after a cell swap\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eThis happens because the fuel gauge IC still holds the discharge curve of the original degraded cell. When the new cell hits a voltage point the old curve mapped to 20–30%, the IC signals a low-voltage shutdown even though real capacity remains. The fix is a single full discharge to auto-off followed by a full uninterrupted charge. After that cycle, the coulomb counter recalibrates and the reported percentage tracks the actual cell state correctly.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eXDA IIS not powering on after extended storage\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eLithium-ion cells left discharged in storage can drop below 2.5V per cell, which triggers BMS lockout — the protection circuit opens and blocks current flow to prevent damage. The device will show nothing on screen and will not respond to the power button. Connect to a wall charger rated at the correct output and leave it undisturbed for 20–30 minutes; the BMS recovery circuit needs a trickle current at or above 3.0V per cell to re-enable the main discharge path before normal charging resumes.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43409438179418,"sku":"BWCS-PH26BDL-1","price":40.99,"currency_code":"USD","in_stock":false},{"title":"Warranty 2 Year","offer_id":43409438212186,"sku":"BWCS-PH26BDL-2","price":46.99,"currency_code":"USD","in_stock":false},{"title":"Warranty 3 Year","offer_id":43409438244954,"sku":"BWCS-PH26BDL-3","price":51.99,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-PH26BDL-big.webp?v=1779579689","url":"https:\/\/batteryweb.com\/products\/mwg-xda-iis-replacement-battery-37v-4200mah-li-ion","provider":"BatteryWeb","version":"1.0","type":"link"}