The KitchenAid Go Cordless Personal Blender is well designed, but lacks the power to tackle tough ingredients.
https://www.techradar.com/home/juicers-blenders/kitchenaid-go-cordless-personal-blender-review
https://www.techradar.com/home/juicers-blenders/kitchenaid-go-cordless-personal-blender-review