Cordless portable blenders weren’t really a thing a decade ago, or maybe even three years ago. But battery tech keeps getting better. This means the best portable blender I’ve tested, the Ninja Blast Max ($100), is now fully able to make a six-pack of crushed-ice margaritas at your next picnic or blend up a berry-filled protein shake at the gym without breaking much of a sweat. Meanwhile, the ingeniously designed Nutribullet Flip ($115) offers more torque than previous-generation blenders, plus enough insulation to keep ice frozen until it’s time for lunch (or even dinner). Does this not jibe with your past experience with cordless blenders? Reader, I agree. It’s a young technology, and most past (and current!) cordless blenders are a disappointment, especially compared to the best blenders that plug into the wall—which are often as much as a hundred times more powerful. But I found that our two top cordless blenders were far superior to the rest, after testing eight of the most promising contenders for battery life, ice crushing, smoothie and milkshake consistency, …