{"product_id":"lg-cu575-replacement-battery-37v-980mah-li-ion","title":"LG CU575 Replacement Battery 3.7V 980mAh Li-ion","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eLG CU575 \/ TU575 — 3.7V Li-ion Replacement Battery (LG-GBJM)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 3.7V, 980mAh Li-ion cell built to the LG-GBJM spec, fitting the LG CU575, Trax CU575, and TU575 candybar handsets. These mid-2000s phones use a slim 70.40 × 46.80 × 5.40mm pack with a three-contact rear connector. Voltage and capacity match the original OEM cell exactly — no modifications needed to seat and run it.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eCU575, Trax CU575, and TU575 fit:\u003c\/strong\u003e\n    All three models share the same battery bay dimensions, connector pinout, and 3.7V nominal voltage rail — one cell covers the full platform without adapter or trim.\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 a CU575 body. The BMS accepted charge from a standard 4.2V termination charger, held voltage above 3.6V through the mid-band of discharge, and tripped the low-voltage cutoff cleanly at the floor without hanging.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFuel gauge recalibration on first use:\u003c\/strong\u003e\n    After fitting this cell, run one full discharge to automatic shutoff before recharging. The CU575 fuel gauge IC is calibrated to the old cell's discharge curve — one complete cycle lets it remap against the new cell and report accurate percentages from the second charge onward.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eWhy the CU575 reports wrong battery percentage after a cell swap\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eThe CU575 uses a simple coulomb-counting fuel gauge IC that stores a learned discharge curve from the previous cell. When a new cell goes in, that stored curve no longer matches the actual voltage-versus-capacity slope of the replacement. The phone may show 40% remaining while the cell is near 3.5V, then drop to 5% without warning. One full discharge-to-cutoff followed by a full charge forces the IC to rebuild its reference map against the new cell. After that single cycle, the percentage readout tracks correctly.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eSudden shutdown at 20–30% on the replacement cell\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eThis is a voltage cliff issue, not a capacity problem. Under the combined load of the GSM modem transmitting and the backlight active, the cell must sustain voltage above roughly 3.4V — if internal impedance is slightly higher than the original cell, voltage dips below the BMS cutoff threshold under that peak draw even when the coulomb count says 25% remains. The phone interprets this as a low-voltage fault and shuts down to protect the cell. Letting the fuel gauge recalibrate over one full cycle resolves most cases; if shutdowns persist, check that the battery contacts on the phone body are clean and making full metal-to-metal contact.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43405258588250,"sku":"BWCS-LCU575SL-1","price":23.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43405258621018,"sku":"BWCS-LCU575SL-2","price":26.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43405258653786,"sku":"BWCS-LCU575SL-3","price":28.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-LCU575SL-1.webp?v=1779370368","url":"https:\/\/batteryweb.com\/products\/lg-cu575-replacement-battery-37v-980mah-li-ion","provider":"BatteryWeb","version":"1.0","type":"link"}