{"product_id":"asus-zenfone-3-deluxe-55-replacement-battery-385v-3300mah-li-polymer","title":"Asus ZenFone 3 Deluxe 5.5 Compatible Battery C11P1603 3.85V","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eAsus ZenFone 3 Deluxe 5.5 \/ ZS550KL — 3.85V Li-Polymer Replacement Battery (C11P1603)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 3.85V, 3300mAh lithium-polymer cell for the Asus ZenFone 3 Deluxe 5.5, ZenFone 3 Deluxe 5.5 Dual SIM, and ZS550KL. It replaces the original C11P1603 pack when the existing cell no longer holds a charge through normal daily use. Rated at 12.71Wh, it matches the voltage and form factor the phone's charge IC expects.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eZS550KL and Dual SIM compatibility:\u003c\/strong\u003e\n    Both variants share the same battery bay dimensions, connector pinout, and BMS handshake. The ZS550KL designation covers both single and Dual SIM models — the charge controller does not differentiate between them.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We ran this cell on a ZS550KL unit and confirmed the BMS accepted the pack without a fault flag. The charge IC entered CC\/CV charging normally, and the fuel gauge IC began tracking state-of-charge from the first cycle.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFirst-cycle fast charge protocol:\u003c\/strong\u003e\n    On first use after installation, disable fast charging for one full discharge-charge cycle. This lets the fuel gauge IC recalibrate against the new cell's discharge curve before high-current charging pushes current into an uncalibrated state.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eWhy the ZenFone 3 Deluxe reports wrong battery percentage after a cell swap\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eThe ZS550KL uses a coulomb-counter-based fuel gauge IC that builds its state-of-charge model against the original cell's discharge curve. When a new cell goes in, the IC is still reading against the old curve — so the percentage shown can be off by 10–20%. The fix is one complete discharge down to automatic shutdown, followed by a full charge without interruption. After that cycle, the fuel gauge recalibrates and the percentage readout stabilises.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eSudden shutdown at 20–30% remaining on the ZS550KL\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThis happens when the cell voltage drops below what the modem or display backlight needs under peak load, even though the fuel gauge still shows capacity remaining. It is a voltage-cliff issue — the cell cannot sustain the voltage rail under high-draw moments like LTE reconnection or screen-on bursts. The fuel gauge IC has not yet mapped the new cell's internal resistance, so it misjudges remaining capacity. Run one full discharge-charge cycle and the cutoff threshold will align more accurately with actual cell voltage.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43392064454746,"sku":"BWCS-AUZ550SL-1","price":26.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43392064487514,"sku":"BWCS-AUZ550SL-2","price":30.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43392064520282,"sku":"BWCS-AUZ550SL-3","price":33.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-AUZ550SL-1.webp?v=1779143562","url":"https:\/\/batteryweb.com\/products\/asus-zenfone-3-deluxe-55-replacement-battery-385v-3300mah-li-polymer","provider":"BatteryWeb","version":"1.0","type":"link"}