{"product_id":"svp-tango-replacement-battery-37v-950mah-li-ion","title":"SVP C4D10T Nokia Tango Compatible Battery 3.7V 950mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eSVP Tango \/ Deco Pro — 3.7V Li-ion Replacement Battery (C4D10T)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis SVP C4D10T is a 3.7V, 950mAh Li-ion cell that replaces the original battery in the Nokia Tango and Deco Pro smartphones. It slots in where the factory cell has degraded and can no longer hold a usable charge. Voltage and connector match the original, so no modification is needed.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eTango and Deco Pro compatibility:\u003c\/strong\u003e\n    Both handsets share the same battery bay dimensions, 3.7V nominal voltage rail, and contact layout — one cell fits both. The BMS on each device uses the same charge termination voltage, so the replacement cell charges correctly on either platform without a firmware change.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We cycled this cell through full discharge and charge sequences on a Nokia Tango unit. The BMS accepted the replacement without triggering a protection cutoff, and the charge IC reached the correct 4.2V termination point on the first cycle.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFuel gauge recalibration on first use:\u003c\/strong\u003e\n    On first installation, disable fast charging if the option is available and run one full discharge down to automatic shutdown, then charge uninterrupted to 100%. This gives the phone's fuel gauge IC one complete reference cycle against the new cell's discharge curve before it starts reporting accurate percentages.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eWhy the Tango reports wrong battery percentage after a cell swap\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eThe Nokia Tango uses a fuel gauge IC that builds its charge estimates from a learned discharge curve stored during previous cycles with the old cell. When a new cell goes in, that stored curve no longer matches the new cell's actual voltage-to-capacity relationship. The IC reads a voltage that maps to the wrong percentage on the old curve, so the display shows figures that don't reflect real remaining charge. One full uninterrupted discharge-charge cycle resets the reference point and brings the reported percentage back into alignment with actual capacity.\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 happens when the modem or display pulls a short burst of high current and the cell voltage drops sharply — past the BMS undervoltage threshold — even though the gauge still reads 20% or higher. It is a voltage cliff, not a capacity problem. A new cell that has not been calibrated yet can trigger this repeatedly in the first few cycles. After two or three full discharge-charge cycles, the fuel gauge IC recalibrates its curve and the shutdowns stop. If they continue past three cycles, check that the battery contacts are clean and making firm contact — a high-resistance connection amplifies the voltage drop under load.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43405136887898,"sku":"BWCS-NK4DSL-1","price":28.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43405136920666,"sku":"BWCS-NK4DSL-2","price":33.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43405136953434,"sku":"BWCS-NK4DSL-3","price":36.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-NK4DSL-1.webp?v=1779370279","url":"https:\/\/batteryweb.com\/products\/svp-tango-replacement-battery-37v-950mah-li-ion","provider":"BatteryWeb","version":"1.0","type":"link"}