{"product_id":"alcatel-1b-2020-replacement-battery-385v-2850mah-li-ion","title":"Alcatel 1B 2020 TLi028C1 Replacement Battery 3.85V 2850mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eAlcatel 1B 2020 \/ OT-5002 Series — 3.85V Li-ion Replacement Battery (TLi028C1)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 3.85V, 2850mAh Li-ion cell replacing the original TLi028C1 in the Alcatel 1B 2020 and OT-5002 series smartphones. It fits variants including the OT-5002A, OT-5002D, and OT-5002F. The physical dimensions match the stock cell: 96.20 × 42.15 × 4.60mm.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eOT-5002 variant compatibility:\u003c\/strong\u003e\n    The OT-5002A, OT-5002D, and OT-5002F share the same battery bay dimensions, connector pinout, and BMS handshake protocol. All three accept the TLi028C1, TLi028C7, and TLi028D7 part numbers interchangeably — same voltage rail, same NTC thermistor line.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We cycled this cell on the OT-5002 platform and monitored BMS communication across charge, discharge, and modem-load spikes. The protection circuit responded correctly to over-current events and held the voltage rail stable under screen-on plus LTE load.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFirst-cycle fast charge tip:\u003c\/strong\u003e\n    On first use after installation, disable fast charging and run one full discharge-to-charge cycle. This lets the fuel gauge IC recalibrate its coulomb counter against the new cell's discharge curve before high-current charging pushes amps into an uncalibrated cell.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eWhy the Alcatel 1B 2020 reports wrong battery percentage after a cell swap\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eThe fuel gauge IC on the 1B 2020 stores a learned discharge curve for the original cell in non-volatile memory. When a new cell goes in, that stored curve no longer matches the new cell's actual voltage-to-capacity relationship. The gauge then maps voltage readings against the wrong reference, producing percentage readings that are off by 10–25%. One complete discharge cycle — run the phone down to automatic shutdown, then charge to 100% uninterrupted — forces the coulomb counter to relearn against the new cell. After that cycle, percentage accuracy returns to normal.\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 cell voltage drops below the load threshold faster than the fuel gauge expects — a voltage cliff. Under combined modem, screen, and CPU load, the cell's internal resistance causes a sharp voltage sag that trips the BMS under-voltage cutoff before the reported percentage reaches zero. It is not a faulty battery; it is an uncalibrated gauge reading a fresh cell. Run two full discharge-charge cycles without interruption. By the second cycle the fuel gauge IC has enough data to shift the low-battery cutoff warning to the correct voltage point — typically around 3.5V per cell.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43391861784666,"sku":"BWCS-OTB502SL-1","price":23.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43391861817434,"sku":"BWCS-OTB502SL-2","price":26.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43391861850202,"sku":"BWCS-OTB502SL-3","price":29.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-OTB502SL-1.webp?v=1779142388","url":"https:\/\/batteryweb.com\/products\/alcatel-1b-2020-replacement-battery-385v-2850mah-li-ion","provider":"BatteryWeb","version":"1.0","type":"link"}