{"product_id":"meizu-m3-replacement-battery-385v-2800mah-li-polymer","title":"BT68 Meizu M3 Replacement Battery 3.85V 2800mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eMeiZu M3 \/ M688 Series — 3.85V Li-Polymer Replacement Battery (BT68)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 3.85V, 2800mAh Li-Polymer replacement cell for the MeiZu M3 smartphone and its M688U, M688Q, and M688M variants. It slots in when the original BT68 has lost capacity or swollen beyond safe use. Capacity figure matches the OEM spec at 10.78Wh.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eM3 and M688 variant compatibility:\u003c\/strong\u003e\n    The M688U, M688Q, and M688M share the same physical footprint, connector pinout, and BMS handshake protocol as the base M3. One cell covers all of them because the voltage rail and charge IC communication lines are identical across that production run.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We ran this cell through the MeiZu charge IC handshake and confirmed BMS recognition on first connection. The protection circuit responded correctly to both low-voltage cutoff and charge-termination signals without requiring a manual reset.\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 map the new cell's discharge curve before high-current charging pushes current into an uncalibrated coulomb counter — which is what causes erratic percentage readings in the first day of use.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eWhy the MeiZu M3 reports wrong battery percentage after a cell swap\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThe M3 uses a coulomb counter IC that builds its reference model from the previous cell's charge and discharge history. When you swap in a new cell, that stored model no longer matches the actual cell chemistry. The mismatch shows up as jumpy percentage readings or a figure that stays frozen for long stretches. One full discharge down to automatic shutdown, followed by an uninterrupted charge to 100%, forces the IC to rebuild its reference against the new cell curve.\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 is a voltage cliff, not a capacity problem. Under peak load — mobile data handoff, screen at full brightness, or a background sync — the cell voltage sags below the BMS cutoff threshold even though the fuel gauge still shows charge remaining. It happens most often in the first few cycles when the gauge IC hasn't finished calibrating. Run two full discharge-charge cycles without fast charging and monitor whether the shutdown point moves lower. If it persists past three cycles, check that the cell connector is fully seated — a high-resistance connection amplifies voltage sag under load.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43392097026138,"sku":"BWCS-MX688SL-1","price":23.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43392097058906,"sku":"BWCS-MX688SL-2","price":26.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43392097091674,"sku":"BWCS-MX688SL-3","price":28.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-MX688SL-1.webp?v=1779143763","url":"https:\/\/batteryweb.com\/products\/meizu-m3-replacement-battery-385v-2800mah-li-polymer","provider":"BatteryWeb","version":"1.0","type":"link"}