{"product_id":"samsung-galaxy-z-flip-4-replacement-battery-388v-1000mah-li-polymer","title":"EB-BF724ABY Samsung Galaxy Z Flip 4 Compatible Battery 3.88V 1000mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eSamsung Galaxy Z Flip 4 — 3.88V Li-Polymer Replacement Battery (EB-BF724ABY)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis 3.88V, 1000mAh Li-Polymer cell replaces the internal battery in the Samsung Galaxy Z Flip 4 (SM-F721U, SM-F721U1, SM-F721W, and related variants). It matches OEM part numbers EB-BF724ABY and GH82-29433A. Capacity is 1000mAh (3.88Wh), identical to the original cell specification.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eZ Flip 4 foldable form factor:\u003c\/strong\u003e\n    The SM-F721 series uses a split-cell layout inside a hinged chassis. This cell fits the inner battery position — same footprint at 56.00 x 25.00 x 4.80mm — and communicates with the device's fuel gauge IC over the same BMS handshake protocol as the OEM unit.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We ran this cell through charge and discharge cycles on Z Flip 4 hardware. The BMS accepted the cell without error flags on the first connection. Charge current stepped correctly through trickle, CC, and CV phases.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFuel gauge recalibration after cell swap:\u003c\/strong\u003e\n    On first use after installation, disable fast charging and run one complete discharge-to-charge cycle. This gives the fuel gauge IC one full pass to recalibrate its coulomb counter against the new cell's discharge curve before high-current charging begins.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eWhy the Z Flip 4 reports wrong battery percentage after a cell swap\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThe Z Flip 4 uses a coulomb-counting fuel gauge IC that builds a discharge model against the original cell over hundreds of cycles. When a new cell goes in, that learned model no longer matches the actual cell chemistry. The gauge reads a stored curve, not the real cell state, so percentage readouts can be off by 10–20% until recalibration occurs. One full discharge to automatic power-off, followed by a full charge to 100%, resets the IC's reference points and restores accurate reporting.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eSudden shutdown at 20–30% on a replacement cell\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThis happens when the modem, display, or processor pulls a short burst of high current that the cell voltage cannot sustain under load. At roughly 20–30% state of charge, cell voltage drops below the BMS cutoff threshold under that transient load — the phone shuts off even though the gauge still shows charge remaining. The fuel gauge IC's stored model has not yet mapped the new cell's actual voltage-capacity curve at that range. Running the recalibration cycle described above — one full discharge and full recharge with fast charge disabled — typically eliminates these shutdowns by aligning the cutoff threshold to the correct voltage point on this cell.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43391801786458,"sku":"BWCS-SMZ724SL-1","price":33.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43391801819226,"sku":"BWCS-SMZ724SL-2","price":39.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43391801851994,"sku":"BWCS-SMZ724SL-3","price":43.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-SMZ724SL-1.webp?v=1779142198","url":"https:\/\/batteryweb.com\/products\/samsung-galaxy-z-flip-4-replacement-battery-388v-1000mah-li-polymer","provider":"BatteryWeb","version":"1.0","type":"link"}