{"product_id":"somfy-515657c-replacement-battery-385v-650mah-li-polymer","title":"Somfy 515657C Compatible Battery 3.85V 650mAh Li-Polymer","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eSomfy Nina IO \/ 515657C Series — 3.85V Li-Polymer Replacement Battery (901642)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 3.85V, 650mAh Li-Polymer cell built to the 901642 OEM specification. It fits Somfy remote controls including the 515657C, 5121348A, Nina IO, and Nina Timer IO — wireless RF remotes used to operate motorised blinds, shades, and automated window coverings. Dimensions are 42.30 × 16.50 × 9.20mm, matching the original cell footprint exactly.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eNina IO and Nina Timer IO compatibility:\u003c\/strong\u003e\n    These remotes share the same 3.85V power rail, connector pinout, and BMS handshake protocol across the 515657C and 5121348A platforms — which is why a single 901642-spec cell covers all four fit models listed.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We ran the cell through charge and discharge cycles on a Nina IO remote. The BMS accepted the cell without fault flags, voltage held steady at 3.85V under normal RF transmission load, and no protection trip was triggered during wake-up polling events.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003ePost-swap network reconnect timing:\u003c\/strong\u003e\n    After installing this cell, wait at least 60 seconds before expecting the remote to respond. Somfy wireless remotes perform a mesh network re-join sequence following any power interruption — pressing buttons before this completes will appear as a non-responsive device but is normal.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eWhy the Nina IO goes offline immediately after a battery swap\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThe Nina IO does not retain its RF channel association during a full power loss. When the cell is removed, the remote's volatile memory clears its last transmission state. On restart, the device broadcasts a re-join request to the Somfy hub, which takes 30–60 seconds to acknowledge. If the remote appears dead after the swap, it is almost always mid re-join — not a cell fault.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eNew battery installed but low-battery alert still showing on the Somfy app\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eLi-Polymer cells can sit in warehouse storage for months, which drops their resting voltage below the app's low-battery alert threshold — typically set around 3.60V. The Somfy hub reads voltage at the first check-in after pairing, and if the cell hasn't recovered to nominal, the alert persists. Leave the remote powered on for 10–15 minutes to allow the cell voltage to stabilise, then trigger a manual refresh in the Somfy app. If the alert clears above 3.75V, the cell is healthy.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43416138383450,"sku":"BWCS-SMN515SL-1","price":46.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43416138416218,"sku":"BWCS-SMN515SL-2","price":54.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43416138448986,"sku":"BWCS-SMN515SL-3","price":60.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-SMN515SL_1.webp?v=1779760424","url":"https:\/\/batteryweb.com\/products\/somfy-515657c-replacement-battery-385v-650mah-li-polymer","provider":"BatteryWeb","version":"1.0","type":"link"}