{"product_id":"qmobile-z8-plus-replacement-battery-38v-3000mah-li-polymer","title":"QMobile Z8 Plus 3.8V Replacement Battery 3000mAh Li-Polymer","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eQMobile Z8 Plus — 3.8V Li-Polymer Replacement Battery (C866640282L)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis 3.8V, 3000mAh Li-Polymer battery replaces part number C866640282L in the QMobile Z8 Plus smartphone. It matches the original cell's voltage, capacity, and connector configuration. Dimensions are 86.60 × 65.90 × 4.00mm — verify against your existing cell before installing.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eZ8 Plus cell compatibility:\u003c\/strong\u003e\n    The Z8 Plus uses a Li-Polymer pouch cell with a specific BMS handshake tied to the phone's charge IC. This replacement carries the same voltage rating and connector pinout, so the charge circuit recognises it without triggering a protection fault on first boot.\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 a controlled bench rig. The BMS held the 4.35V upper cutoff correctly and did not trip the protection circuit under simulated modem and screen 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 fast charging and run one complete discharge-charge cycle at standard current. This gives the fuel gauge IC time to map its coulomb counter against the new cell's discharge curve before high-current charging begins on 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\"\u003eSudden shutdown at 20–30% on the Z8 Plus after a cell swap\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eA new cell has a different internal resistance profile than the aged cell the fuel gauge IC was calibrated against. Under heavy load — active LTE, screen at full brightness, GPS — the cell voltage drops sharply. The phone's protection circuit reads this as a critically low voltage event and cuts power, even though the reported percentage looks safe. One full discharge-charge cycle resets the coulomb counter and tightens the percentage-to-voltage mapping. After calibration, the shutdowns typically stop.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eUSB fast charge not activating on the first cycle after replacement\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThe Z8 Plus charge IC negotiates fast charge protocols with the BMS on the cell. A new BMS may not complete this handshake successfully on the first charge cycle, causing the phone to fall back to standard 5V charging. This is not a fault with the battery or the charger. Fully discharge the phone, then plug in using the original cable and charger — on the second or third cycle the handshake completes and fast charge activates normally at the expected input voltage.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43392103284826,"sku":"BWCS-QMZ800SL-1","price":26.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43392103317594,"sku":"BWCS-QMZ800SL-2","price":29.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43392103350362,"sku":"BWCS-QMZ800SL-3","price":32.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-QMZ800SL-1.webp?v=1779143815","url":"https:\/\/batteryweb.com\/products\/qmobile-z8-plus-replacement-battery-38v-3000mah-li-polymer","provider":"BatteryWeb","version":"1.0","type":"link"}