{"product_id":"nokia-lumia-950-xl-replacement-battery-39v-2950mah-li-ion","title":"Nokia Lumia 950 XL Replacement Battery BV-T4D 3.9V 2950mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eNokia Lumia 950 XL — 3.9V Li-ion Replacement Battery (BV-T4D)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 3.9V Li-ion replacement cell rated at 2950mAh (11.51Wh), built to the BV-T4D specification. It fits the Lumia 950 XL, Lumia 950 XL Dual SIM, and Cityman variants. If your original cell has degraded, swells, or no longer holds a charge through a normal day, this is the direct swap.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eLumia 950 XL and Cityman compatibility:\u003c\/strong\u003e\n    All three variants — standard, Dual SIM, and Cityman — share the same battery bay dimensions and BV-T4D connector footprint. The BMS handshake and NFC-adjacent pad layout are identical across the lineup, so one cell covers all three.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We ran this cell through full charge and discharge cycles on a Lumia 950 XL unit. The BMS accepted charge current correctly, thermal reporting stayed within normal range, and the USB-PD fast charge protocol engaged without error flags after the first calibration cycle.\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 fast charging for one complete discharge-charge cycle. This lets the fuel gauge IC recalibrate against the new cell's discharge curve before high-current charging pushes current into an uncalibrated cell — preventing false percentage readings from the first day.\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 Lumia 950 XL replacement cell\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eThis is a voltage cliff issue, not a capacity problem. When the modem fires up for a call or the screen hits full brightness, current draw spikes sharply. A new cell that hasn't been calibrated yet may sag below the BMS cutoff threshold — around 3.0V under load — even though the fuel gauge still shows 20–30% remaining. The fix is one full uninterrupted discharge-charge cycle with fast charging disabled. After that cycle, the coulomb counter aligns to the actual cell curve and the shutdowns stop.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eUSB-PD fast charge not working on first cycle after replacement\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eAfter a cell swap, the Lumia 950 XL's charge IC sometimes refuses to negotiate the USB-PD fast charge contract on the first cycle. The BMS on a new, fully uncalibrated cell presents a different impedance profile than the aged cell it replaced, which causes the charge IC to fall back to standard 5V charging as a safety measure. Let the phone complete one full charge on a standard 5V USB source before switching back to the fast charger. Once the BMS has completed that first cycle, fast charge should negotiate normally — confirm by checking that the phone reports \"charging rapidly\" in the lock screen status.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43392099319898,"sku":"BWCS-NK950SL-1","price":26.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43392099352666,"sku":"BWCS-NK950SL-2","price":30.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43392099385434,"sku":"BWCS-NK950SL-3","price":33.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-NK950SL-1.webp?v=1779143764","url":"https:\/\/batteryweb.com\/products\/nokia-lumia-950-xl-replacement-battery-39v-2950mah-li-ion","provider":"BatteryWeb","version":"1.0","type":"link"}