{"product_id":"berner-bacag-replacement-battery-18v-4000mah-li-ion","title":"Berner BACAG 18V Li-ion Replacement Battery 4000mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eBerner BACAG Series — 18V Li-ion Replacement Battery (BBP 18 \/ 175187)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis 18V, 4000mAh Li-ion pack replaces the original battery on Berner BACAG, BACCG, BACDE, BACDWD BL, and compatible cordless power tools. It slots into the same rail and communicates with the tool's BMS using the original connector pinout. Voltage and capacity match the OEM spec exactly — 18V nominal, 72Wh total.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eBACAG and BACCG platform compatibility:\u003c\/strong\u003e\n    These models share the same 18V rail, connector geometry, and BMS handshake protocol — which is why one pack covers the full lineup. Swapping between a drill and an impact driver on the same platform works without any adapter or firmware issue.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We cycled this pack through repeated inrush events on a cordless drill and impact driver. The BMS tracked current spikes at trigger pull without tripping overcurrent protection under normal operating conditions. Cell voltage recovery after each discharge cycle stayed within expected bounds.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eMotor inrush conditioning on first use:\u003c\/strong\u003e\n    On the first two cycles, run the tool at moderate load — mid-torque drilling, not max-torque fastening. This lets the BMS log the motor's inrush current signature before it locks overcurrent thresholds. Skipping this on a fresh pack increases the chance of nuisance trips on the first heavy job.\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 surge with the BACAG drill\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eAt trigger pull, a cordless drill motor draws a current spike — sometimes 3–5× the steady running current — before the armature reaches speed. A freshly installed or storage-depleted pack has a higher internal resistance, which amplifies the voltage sag during that inrush window. If the sag breaches the BMS undervoltage threshold, the pack shuts off instantly even though the cells aren't depleted. Fully charging the pack before the first heavy use and conditioning with two moderate-load cycles brings cell resistance down and reduces sag at trigger pull.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eTool bogs under sustained load after the battery shows full charge\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eA full charge indicator doesn't rule out voltage sag under load — it only confirms resting cell voltage. When contact resistance at the rail terminals rises due to debris or oxidation, the voltage drop under load increases and the tool loses torque mid-task. Clean the battery terminals and tool contacts with isopropyl alcohol, then check rail seating — the pack should click firmly and show no lateral play. If sag continues after cleaning, measure resting voltage with a multimeter; a healthy 18V Li-ion pack reads 20V–21V at full charge and should not drop below 16V under moderate tool load.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43416057610330,"sku":"BWCS-MKM180PX-1","price":96.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43416057643098,"sku":"BWCS-MKM180PX-2","price":112.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43416057675866,"sku":"BWCS-MKM180PX-3","price":125.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-MKM180PX-1.webp?v=1779759860","url":"https:\/\/batteryweb.com\/products\/berner-bacag-replacement-battery-18v-4000mah-li-ion","provider":"BatteryWeb","version":"1.0","type":"link"}