{"product_id":"aeg-bfl-18-replacement-battery-18v-4000mah-li-ion","title":"AEG L1815R 18V Cordless Drill Replacement Battery 4000mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eAEG BFL 18 \/ BKS 18 Series — 18V Li-ion Replacement Battery (L1815R \/ L1830R)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis 18V 4000mAh Li-ion battery replaces the L1815R and L1830R packs used across the AEG 18V cordless platform. It fits the BFL 18 drill\/driver, BHO 18 orbital sander, BKS 18 circular saw, BMS 18C multi-saw, and more than ten additional AEG 18V tools. Voltage and cell chemistry match the original specification.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eAEG 18V platform fit:\u003c\/strong\u003e\n    These models share a common 18V slide-rail interface and BMS handshake protocol. The pack connector, latch geometry, and communication line pinout are identical across the BFL 18, BKS 18, BHO 18, and BMS 18C — one battery seats and communicates correctly in all of them.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We cycled this pack on a BFL 18 and a BKS 18. The BMS accepted charge without fault codes, held the voltage rail steady under sustained load, and the overcurrent protection tripped correctly when we pushed past the motor-start inrush threshold in a controlled test.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eMotor inrush break-in:\u003c\/strong\u003e\n    On first use, run the drill or saw at half load for two cycles before full-torque applications. This gives the BMS time to profile the inrush current draw from the specific motor before it sets its overcurrent protection thresholds — reducing nuisance trips during heavy-duty fastening or rip cuts.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eBMS cutoff on circular saw motor-start inrush surge\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThe BKS 18 circular saw draws a sharp current spike the instant the blade spins up under load. If the BMS has not yet mapped the motor's inrush profile — common with a new or freshly charged pack — it can read that spike as a fault and cut power before the blade reaches full speed. This is a protection circuit response, not a faulty battery. Running two light-load cycles first allows the BMS to set a realistic overcurrent threshold so it stops tripping on normal motor start.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eCharger not recognising the pack after storage\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eA pack stored for several months can drop below the charger's acceptance voltage — typically around 12V on an 18V Li-ion pack — causing the charger LED to blink red or show no response at all. The charger's intake circuit interprets anything below that floor as a damaged cell and refuses to begin a charge cycle. To recover the pack, some AEG chargers have a recovery mode: leave the pack seated for 10–15 minutes and the charger will attempt a low-current trickle to bring cells back above the acceptance threshold. If the pack fails to recover after two attempts at 12.5V or above, the cells have self-discharged past safe recovery.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43416014258266,"sku":"BWCS-RDD840PH-1","price":108.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43416014291034,"sku":"BWCS-RDD840PH-2","price":127.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43416014323802,"sku":"BWCS-RDD840PH-3","price":142.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-RDD840PH-1.webp?v=1779759486","url":"https:\/\/batteryweb.com\/products\/aeg-bfl-18-replacement-battery-18v-4000mah-li-ion","provider":"BatteryWeb","version":"1.0","type":"link"}