{"product_id":"lithonia-daybright-d-aa650bx4-replacement-battery-48v-2000mah-ni-mh","title":"Lithonia OSA152 Emergency Light Replacement Battery 4.8V 2000mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eLithonia Daybright D-AA650BX4 Series — 4.8V Ni-MH Replacement Battery (OSA152)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 4.8V 2000mAh Ni-MH replacement battery pack for the Lithonia Daybright D-AA650BX4 and D-AA650BX4 LONG emergency lighting units. It slots into the fitting in place of the original OSA152 cell pack and powers the lamp during mains failure. Capacity is 2000mAh (9.6Wh), matching the original specification.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eD-AA650BX4 and D-AA650BX4 LONG compatibility:\u003c\/strong\u003e\n    Both units share the same 4.8V four-cell sub-C Ni-MH configuration, identical connector pinout, and the same charge controller float voltage. The same pack fits both 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 D-AA650BX4 charge controller and confirmed the BMS accepted the cell voltage on first connection. The charge indicator transitioned from red to green within the expected window, and the pack held load across a full test-button activation cycle.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFirst installation test cycle:\u003c\/strong\u003e\n    Within 24 hours of fitting, hold the test button for the full rated duration. This confirms the new cells accept load and lets the charge controller register actual cell capacity before your next scheduled compliance test.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eCharge indicator staying red after new battery installation\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eNi-MH cells shipped in partial-discharge state often sit outside the narrow float acceptance window the D-AA650BX4 charge controller expects on first connection. The controller reads the resting voltage, decides the cell is faulty, and holds the fault state without starting the charge cycle. Leave the fitting powered for 12–24 hours before drawing any conclusions — most controllers will re-sample and begin charging once the cell voltage drifts into range. If the indicator is still red after 24 hours of continuous mains power, measure the pack voltage directly; a healthy starting voltage should be at or above 4.0V.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eEmergency light dims or cuts out partway through the duration test\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eA new pack that has not completed a full charge cycle will show rated voltage at rest but sag quickly under the lamp load during a test. This is not a cell defect — it is a shallow initial charge from storage. The fix is straightforward: allow a minimum 24-hour uninterrupted charge on mains before running the duration test. If the light still dims after that conditioning period, check the charge controller output with a multimeter; the trickle charge voltage to the pack should read between 5.4V and 5.8V across the terminals.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43360427442266,"sku":"BWCS-LTL152LS-1","price":14.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43360427475034,"sku":"BWCS-LTL152LS-2","price":15.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43360427507802,"sku":"BWCS-LTL152LS-3","price":16.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-LTL152LS-1.webp?v=1778614656","url":"https:\/\/batteryweb.com\/products\/lithonia-daybright-d-aa650bx4-replacement-battery-48v-2000mah-ni-mh","provider":"BatteryWeb","version":"1.0","type":"link"}