{"product_id":"att-u-verse-nvg589-replacement-battery-74v-5600mah-li-ion","title":"AT\u0026T U-Verse NVG589 Replacement Battery 7.4V 5600mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eAT\u0026amp;T U-Verse NVG589 \/ NVG599 Gateway — 7.4V Li-ion Replacement Battery (586185-001-00)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis 7.4V, 5600mAh lithium-ion battery is the backup power cell for the AT\u0026amp;T U-Verse NVG589 and NVG599 residential gateways. It sits inside the modem and keeps the unit running during a mains power outage — maintaining your internet connection and, critically, your VoIP line for emergency calls. It replaces OEM part numbers 586185-001-00 and 586185-002-00.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eNVG589 and NVG599 compatibility:\u003c\/strong\u003e\n    Both gateways use the same battery bay, connector pinout, and BMS handshake protocol. AT\u0026amp;T deployed these units across U-Verse service areas with identical internal battery specs, so one cell covers both gateway models without modification.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We ran this cell on an NVG589 and monitored the charge acceptance cycle. The modem's battery management firmware negotiated with the cell's BMS correctly — charge current ramped in, held at float, and the status LED shifted from amber to green at full charge.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003ePost-install charge requirement:\u003c\/strong\u003e\n    After installing, let the modem charge the battery for a full 4 hours before testing backup mode. The NVG589 firmware will not activate the battery for emergency power until it records a complete charge cycle — triggering an outage test before then shows a failed result even if the cell is good.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eModem showing battery error after new cell installation\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eThe NVG589 gateway runs an automated battery validation routine after any power cycle or cell swap. Until the firmware logs a complete charge cycle from the new cell, it reports a battery fault — even when the cell itself is functioning correctly. This is not a defective battery. The error clears on its own once the modem has charged the cell to full capacity, which takes up to 4 hours on a fresh battery. If the error persists beyond 24 hours, check that the battery connector is fully seated — the latch clicks twice when locked.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eInternet stays up during outage but VoIP drops immediately\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eThe NVG589 prioritises load shedding when it switches to battery power — data traffic draws less sustained current than the VoIP subsystem. If the battery has not completed a full charge cycle, the modem may sustain the data connection but shut down the VoIP processor first to protect the remaining charge. A partially charged cell delivering around 7.0V under load hits the VoIP cutoff threshold before the data radio. Let the battery charge fully — verified by a solid green battery LED — then retest VoIP by briefly disconnecting mains power.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43333521047642,"sku":"BWCS-ART589RC-1","price":65.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43333521080410,"sku":"BWCS-ART589RC-2","price":77.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43333521113178,"sku":"BWCS-ART589RC-3","price":86.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-ART589RC-1.webp?v=1778212933","url":"https:\/\/batteryweb.com\/products\/att-u-verse-nvg589-replacement-battery-74v-5600mah-li-ion","provider":"BatteryWeb","version":"1.0","type":"link"}