{"product_id":"samsung-sgh-n620-replacement-battery-37v-900mah-li-ion","title":"Samsung SGH-N620 Replacement Battery BST0698DE 3.7V 900mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eSamsung SGH-N620 Series — 3.7V Li-ion Replacement Battery (BST0698DE)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 3.7V, 900mAh Li-ion cell that replaces the original BST0698DE and BST0698SE batteries in early-2000s Samsung compact mobile phones. It fits the SGH-N620, SGH-N600, SGH-N628, and SGH-K90. Each cell ships at partial charge — top it off before first use.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eSGH-N620, N600, N628, K90 compatibility:\u003c\/strong\u003e\n    These four models share the same battery bay dimensions, 3.7V nominal rail, and BST-series connector pinout. The BMS handshake on all four accepts the same charge termination signal, so one cell covers the full group without modification.\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 an SGH-N620 unit. The BMS hit charge termination correctly at 4.2V, and the protection circuit tripped at the expected low-voltage cutoff without error flags.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFuel gauge recalibration on first cycle:\u003c\/strong\u003e\n    After fitting the new cell, run one full discharge down to automatic shutdown, then charge uninterrupted to 100%. The phone's fuel gauge IC was calibrated to the old cell's discharge curve — one complete cycle rewrites the reference baseline so percentage readings track accurately.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eWhy the SGH-N620 reports wrong battery percentage after a cell swap\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eSamsung's fuel gauge IC on the N620 stores a learned discharge curve from the original cell. When a new cell goes in, that stored curve no longer matches actual cell chemistry, so the percentage display drifts or jumps. The IC needs a full discharge-to-shutdown followed by an uninterrupted charge to 100% to rewrite its internal reference. Until that cycle completes, readings can be off by 15–25%. After one full cycle, the gauge stabilises and tracks the new cell accurately.\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 drops sharply under the load of an active call or backlit display — a voltage cliff the fuel gauge doesn't anticipate. The phone's protection circuit reads the sag as a low-voltage event and cuts power before the displayed percentage reaches zero. It's not a faulty cell — it means the fuel gauge IC hasn't finished recalibrating against the new cell's discharge curve. Run one complete discharge-to-shutdown and full recharge cycle. After that, the gauge accounts for load-induced sag and shutdown moves to the correct threshold near 3.0V per cell.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43409455775834,"sku":"BWCS-SMN620SL-1","price":22.99,"currency_code":"USD","in_stock":false},{"title":"Warranty 2 Year","offer_id":43409455808602,"sku":"BWCS-SMN620SL-2","price":25.99,"currency_code":"USD","in_stock":false},{"title":"Warranty 3 Year","offer_id":43409455841370,"sku":"BWCS-SMN620SL-3","price":27.99,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-SMN620SL-big.webp?v=1779579736","url":"https:\/\/batteryweb.com\/products\/samsung-sgh-n620-replacement-battery-37v-900mah-li-ion","provider":"BatteryWeb","version":"1.0","type":"link"}