{"product_id":"milwaukee-m4-replacement-battery-4v-2000mah-li-ion","title":"Milwaukee M4 4V Replacement Battery 48-11-2001 2000mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eMilwaukee M4 Series — 4V Li-ion Replacement Battery (48-11-2001)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 4V Li-ion replacement battery rated at 2000mAh (8Wh), built to the same electrical spec as the original 48-11-2001. It fits the Milwaukee M4, M4 1\/4\", and M4 4V compact tool platform. Swap it into any M4-compatible charger and you're back to work.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eM4 platform compatibility:\u003c\/strong\u003e\n    The M4, M4 1\/4\", and M4 4V tools share a single 4V rail and the same battery interface connector. The BMS on this pack communicates the same charge-acceptance and discharge-limit signals the charger and tool expect, so there's no handshake mismatch across the three variants.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We cycled this pack through repeated trigger-pull events on an M4 driver to confirm the BMS handles motor-start inrush current without tripping. Cell voltage stayed above the BMS cutoff floor at full draw, and the charger accepted the pack without a fault code.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBreak-in under the M4 motor inrush:\u003c\/strong\u003e\n    On first use, run your M4 tool at half load for two cycles before driving at maximum torque. This lets the BMS log the actual inrush current profile of your specific motor and set its overcurrent thresholds accordingly — reducing nuisance cutoffs 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 M4 motor-start inrush surge\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eWhen you pull the trigger on an M4 drill or driver, the motor draws a short inrush spike that can be several times the steady-state current. A new battery with a freshly calibrated BMS may interpret that spike as an overcurrent fault and cut power immediately. The protection circuit resets once current drops back to zero, so releasing and re-pulling the trigger usually restores operation. After two or three full work cycles, the BMS settles its threshold and the cutoffs stop.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eCharger won't recognise the pack after storage\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eIf a 4V Li-ion cell sits unused for an extended period, cell voltage can drift below the charger's acceptance window — typically around 2.5V per cell. The charger sees the pack as faulty and blinks red or simply does nothing. Place the battery in the charger and leave it for 10–15 minutes; many Milwaukee chargers include a recovery mode that trickle-charges the cell back above the acceptance threshold before switching to normal charge. If the charger still refuses after 20 minutes, measure pack voltage at the terminals — below 2.5V total requires a bench trickle at no more than 100mA to recover.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43416049188954,"sku":"BWCS-MKM400PW-1","price":31.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43416049221722,"sku":"BWCS-MKM400PW-2","price":36.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43416049254490,"sku":"BWCS-MKM400PW-3","price":39.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-MKM400PW-1.webp?v=1779759860","url":"https:\/\/batteryweb.com\/products\/milwaukee-m4-replacement-battery-4v-2000mah-li-ion","provider":"BatteryWeb","version":"1.0","type":"link"}