Two models side by side: measurements taken by the author in their reviews, and their conclusions. The better value in each row is highlighted.
In brief: Based on review measurements: Capacity: BL1850 (4795 mAh vs. 3670); Energy: BL1850 (88.43 Wh vs. 65); Test current: BL1850 (30 A vs. 10); Resistance: M18 battery (15 mΩ vs. 35).
Only in one review: Voltage 18 V (M18 battery); Temperature rise 74 °C (BL1850); Weight 655 g (M18 battery).
BL1850: A pack with genuine high-current cells delivered about 4,800 mAh; the author says it is worth buying.
M18 battery: The case and protection are decent, but capacity is about 4 Ah instead of the claimed 6 Ah; the author advises against buying it.
Figures were taken from the review text and checked against the quoted passages. Measurement conditions differ between reviews, so read the reviews yourself before buying. Prices at the time of review.
BL1850TPcell · 2023Read review →
M18 batteryMilwaukee · 2021Read review →