{"product_id":"aeg-bll12c-replacement-battery-12v-4000mah-li-ion","title":"AEG BLL12C 12V Replacement Battery 4000mAh Li-ion","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eAEG BLL12C \/ BS12C Series — 12V Li-ion Replacement Battery (L1215R)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 12V, 4000mAh Li-ion battery pack built to fit AEG compact cordless tools including the BLL12C, BS12C, BS12C2, and BSS12C. It replaces OEM part numbers L1215, L1215R, L1215P, L1220, L1230, L1230R, L1240, and related 4932 series codes. Voltage and capacity match the original spec exactly.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eBLL12C and BS12C platform fit:\u003c\/strong\u003e\n    These models share a common 12V rail, identical battery slot geometry, and the same BMS handshake protocol. One pack fits all of them without adapter plates or wiring changes.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We ran this pack through AEG's standard charger cycle and confirmed BMS communication, cell balancing, and charge termination all behaved correctly. No false fault codes triggered during discharge testing.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eMotor inrush conditioning on first use:\u003c\/strong\u003e\n    On the first two uses, run the drill at half load before going to full torque. This lets the BMS record the motor's inrush current signature and set overcurrent thresholds accurately — reducing false cutouts during aggressive trigger pulls later.\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 motor-start inrush in the BLL12C and BS12C\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eWhen you pull the trigger hard on a cold pack, the motor draws a sharp current spike — often 3 to 5 times the steady running current. If the BMS hasn't profiled the motor yet, it may read that spike as a fault and cut power instantly. This is not a defective battery. The BMS is doing its job. Two or three moderate-load cycles teach the BMS the difference between a normal start spike and a genuine overcurrent event.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eCharger flashing red and refusing to accept the pack after storage\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eLi-ion cells left unused for several months can drop below the charger's acceptance threshold — typically around 2.5V per cell. The AEG charger reads this as a damaged or incompatible pack and flashes red instead of starting a charge cycle. To recover the pack, some AEG chargers have a recovery or \"boost\" mode — hold the pack in the charger for 10–15 minutes without removing it, and the charger may initiate a low-current trickle to bring cells back above 3.0V per cell before switching to normal charge. If the red light persists past 20 minutes, check the rail voltage at the pack terminals — below 9V total on a 12V pack means the cells need professional assessment.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43416048042074,"sku":"BWCS-RDD860PH-1","price":73.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43416048074842,"sku":"BWCS-RDD860PH-2","price":86.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43416048107610,"sku":"BWCS-RDD860PH-3","price":95.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-RDD860PH-1.webp?v=1779759861","url":"https:\/\/batteryweb.com\/products\/aeg-bll12c-replacement-battery-12v-4000mah-li-ion","provider":"BatteryWeb","version":"1.0","type":"link"}