{"product_id":"билайн-e400-replacement-battery-37v-1300mah-li-ion","title":"ZTE E400 Replacement Battery 3.7V 1300mAh Li-ion","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eБилайн E400 — 3.7V Li-ion Replacement Battery\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 3.7V, 1300mAh Li-ion battery for the Билайн E400 smartphone. It replaces the original cell when the device no longer holds charge or shuts down unexpectedly. Capacity is 4.81Wh — matched to the original specification.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eE400 platform fit:\u003c\/strong\u003e\n    The E400 uses a compact 43.50 × 47.00 × 6.10mm cell with a 3.7V nominal rail. This battery matches that form factor and voltage — the BMS handshake initialises on first boot without requiring a firmware update or additional configuration.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We cycled this cell through charge and discharge on the E400 platform. The BMS accepted the new cell without triggering a protection cutoff, and the charge IC ramped current normally through CC and CV phases.\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 available and run one complete discharge-charge cycle before normal use. The fuel gauge IC on the E400 is calibrated to the old cell's discharge curve — skipping this step causes erratic percentage readings until the coulomb counter resets against the new 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 E400 reports wrong battery percentage after a cell swap\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eThe E400's fuel gauge IC tracks charge state using a learned discharge curve from the previous cell. A new cell has a different internal impedance profile, so the IC's stored curve no longer matches real voltage behaviour. The result is percentage jumps, incorrect time-to-empty readings, or a sudden drop from 30% to zero. One full discharge-charge cycle rewrites the coulomb counter reference and brings percentage reporting back in line.\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 collapses under modem or screen load before the OS reads a low-battery warning. A fresh Li-ion cell can show a steep voltage cliff in the lower charge range while the fuel gauge still reads 20–30%. The E400's protection circuit cuts power when cell voltage drops below roughly 3.0V under load — even if the displayed percentage looks safe. Run two full cycles to let the fuel gauge IC map the new cell's actual voltage-capacity curve and reduce the gap between displayed and real charge state.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43405093109850,"sku":"BWCS-ZTE950SL-1","price":27.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43405093142618,"sku":"BWCS-ZTE950SL-2","price":31.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43405093175386,"sku":"BWCS-ZTE950SL-3","price":33.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-ZTE950SL-1.webp?v=1779369970","url":"https:\/\/batteryweb.com\/products\/%d0%b1%d0%b8%d0%bb%d0%b0%d0%b9%d0%bd-e400-replacement-battery-37v-1300mah-li-ion","provider":"BatteryWeb","version":"1.0","type":"link"}