{"product_id":"spectralink-8400-replacement-battery-37v-1800mah-li-polymer","title":"SpectraLink 8400 Cordless Phone Compatible Battery 3.7V 1800mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eSpectraLink 8400 Series — 3.7V Li-Polymer Replacement Battery (1520-37214-001)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis 3.7V, 1800mAh Li-Polymer battery replaces the original pack in SpectraLink 8400, 8450, 8452, and RS657 cordless handsets. These are DECT phones used in enterprise wireless environments — hospitals, warehouses, and office campuses. When the original battery no longer holds a charge, this replacement restores the handset to full operation.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003e8400, 8450, 8452, and RS657 compatibility:\u003c\/strong\u003e\n    These four models share the same Li-Polymer cell format, voltage rail, and connector spec. The BMS in each handset communicates with the pack over the same charge circuit, so one battery covers all four variants without modification.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We ran this pack through the full charge cycle on a SpectraLink 8450 handset. The BMS accepted the pack immediately, completed a full charge without interruption, and the protection circuit responded correctly to both over-voltage and under-voltage thresholds.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFirst-charge protocol for Li-Polymer handsets:\u003c\/strong\u003e\n    Place the handset in the base immediately after installing this pack and allow a full uninterrupted charge before first use. Li-Polymer cells in DECT handsets are often shipped at partial charge — starting from a full state improves cycle consistency from day one.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eWhy SpectraLink handsets lose range after a battery swap\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eRF transmit power on DECT handsets draws directly from the battery voltage. When a degraded or partially charged Li-Polymer cell sags under that load, the handset reduces transmit power to protect the circuit. This makes range feel shorter even though the handset appears to be working normally. A fully charged, healthy pack maintains the voltage headroom the radio needs to hold full transmit power at the edge of coverage. If range improves after a full charge cycle, the battery was the cause.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eHandset not pairing with the base after battery replacement\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eRemoving a battery from a DECT handset cuts all power to volatile memory. Some SpectraLink models store DECT pairing credentials in memory that is not retained without a power source, so the handset comes back up without a registered base. This is not a fault with the replacement battery. Re-register the handset at the base station using the standard DECT subscription process — on most SpectraLink systems, hold the handset close to the base, navigate to Settings, and initiate registration. The handset will reconnect once it receives the base station system ID.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43339880824922,"sku":"BWCS-SPT845CL-1","price":33.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43339880857690,"sku":"BWCS-SPT845CL-2","price":38.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43339880890458,"sku":"BWCS-SPT845CL-3","price":42.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-SPT845CL-1.webp?v=1778366873","url":"https:\/\/batteryweb.com\/products\/spectralink-8400-replacement-battery-37v-1800mah-li-polymer","provider":"BatteryWeb","version":"1.0","type":"link"}