{"product_id":"funktel-d11-replacement-battery-37v-1200mah-li-ion","title":"Funktel D11 Cordless Phone Compatible Battery 3.7V 1200mAh A051","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eFunktel D11 \/ FC11 — 3.7V Li-ion Replacement Battery (A051)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 3.7V 1200mAh Li-ion battery for the Funktel D11, DECT D11, and FC11 cordless handsets. It replaces OEM part number A051. Swap it in when the original pack no longer holds a charge through a normal day of use.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eD11, DECT D11, and FC11 compatibility:\u003c\/strong\u003e\n    All three handsets share the same battery bay geometry, 3.7V Li-ion cell requirement, and A051 connector orientation — the same pack covers all three 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 a charge cycle and confirmed the BMS holds the cell voltage within the 3.7V nominal rail. Protection circuitry tripped correctly at the low-voltage cutoff, with no anomalous discharge behaviour during standby simulation.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFirst charge on the D11 handset:\u003c\/strong\u003e\n    After fitting this battery, seat the handset in the base and leave it for a full charge before making any calls. Li-ion cells arriving from storage sit at partial charge — giving them a complete first cycle lets the BMS calibrate the state-of-charge tracking correctly.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eTalk time shorter than expected after fitting the A051\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eA new Li-ion pack shipped from storage arrives at around 50–60% charge, and the handset's fuel gauge may read that as a full cell. That mismatch skews the discharge curve, making the battery appear to run out early. Put the handset through two or three full charge-and-use cycles to let the BMS recalibrate against the actual 1200mAh capacity. After the third cycle, talk time should reflect the rated 4.44Wh energy capacity of the cell.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eBase station shows no charge indicator after battery swap\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eIf the base station shows no charge light after fitting the new pack, the cell voltage may have dropped below the base's charge-acceptance threshold during storage. Remove the handset, hold the power button for five seconds to fully power off, then reseat it in the base. This forces the base to restart its charge detection handshake at the current cell voltage — typically 3.5–3.6V is enough for the base to recognise the pack and begin charging.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43339915952218,"sku":"BWCS-AY4020CL-1","price":22.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43339915984986,"sku":"BWCS-AY4020CL-2","price":25.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43339916017754,"sku":"BWCS-AY4020CL-3","price":27.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-AY4020CL_1.webp?v=1778366906","url":"https:\/\/batteryweb.com\/products\/funktel-d11-replacement-battery-37v-1200mah-li-ion","provider":"BatteryWeb","version":"1.0","type":"link"}