{"product_id":"hyundai-bp-d125-replacement-battery-37v-1200mah-li-ion","title":"Hyundai BP-D125 Replacement Battery 3.7V 1200mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eHyundai BP-D125 — 3.7V Li-ion Replacement Battery\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 3.7V, 1200mAh Li-ion cell built to replace the original battery in the Hyundai BP-D125 mobile phone. It fits directly into the BP-D125 and restores power to calling, messaging, and standard applications. Dimensions are 53.00 × 33.90 × 5.70mm — confirm these against your existing cell before installing.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eBP-D125 fit:\u003c\/strong\u003e\n    This cell matches the BP-D125's voltage rail and physical footprint. The connector orientation and BMS handshake align with what the phone's charge IC expects on a standard 3.7V single-cell Li-ion pack.\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 a compatible 3.7V single-cell platform. The BMS held cutoff correctly at both the low-voltage floor and full-charge ceiling with no thermal events noted.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFuel gauge recalibration on first install:\u003c\/strong\u003e\n    On first use after installation, disable fast charging for one complete 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 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 BP-D125 after a cell swap\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eThe fuel gauge IC in the BP-D125 stores a discharge curve calibrated to the original cell. A new cell has a slightly different internal resistance profile, so the IC misjudges the remaining voltage under load. When the modem fires during a call or the screen brightness spikes, actual cell voltage drops below the shutdown floor before the displayed percentage reaches zero. The phone cuts out to protect the cell. One full discharge-to-charge cycle lets the coulomb counter reset against the new cell's actual curve and eliminates most of these early shutdowns.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eDevice not powering on after the replacement cell sat in storage\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eLi-ion cells self-discharge during storage. If the BP-D125 replacement cell dropped below approximately 2.5V per cell during transit or shelf time, the BMS enters lockout to prevent damage from deep discharge. The phone will show no response — no boot screen, no charging indicator. Connect the phone to a wall charger and leave it untouched for 15–20 minutes. The charge IC will trickle current into the cell at a safe rate until voltage climbs back above the BMS re-enable threshold, typically around 2.9V, at which point normal charging resumes.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43404178653274,"sku":"BWCS-JTP127SL-1","price":23.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43404178686042,"sku":"BWCS-JTP127SL-2","price":27.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43404178718810,"sku":"BWCS-JTP127SL-3","price":29.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-JTP127SL-1.webp?v=1779369289","url":"https:\/\/batteryweb.com\/products\/hyundai-bp-d125-replacement-battery-37v-1200mah-li-ion","provider":"BatteryWeb","version":"1.0","type":"link"}