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PRIUS acceleration issue/gas mileage down

My 2010 Prius since new, during cold Central IL weather, when I pull out onto the city street, it accelerates VERY SLOWLY no matter how I work the accelerator for 1-2 blocks. Then it takes off normally. When I forget to allow the extra time, it can be scary to have a car coming up fast and not be able to accelerate. I have left it at the dealership for 3 overnights now over 3 years. They went from “couldn’t duplicate” to “there is a slight hesitation” that they attribute to normal shift from electric to gasoline. The next morning it took 2 blocks before it kicked in. Any ideas? Any one had the same problem? My gas mileage has only been 35 this winter; I don’t believe it has ever been consistently that low. Feedback, please!

Hopefully you are not out of warranty, let the dealer experience and fix it.

Cold weather affects batteries. The Prius is supposed to have a warmer to keep the battery pack running optimally. If the warmer is not working or the battery is damaged and not putting out enough, I can see you having trouble accelerating from a stop, since the Prius uses the electric motor first, then the gas motor. The car is probably already using the gas motor more due to lack ofelectric motor power, reducing your mileage. A battery pack load test should be performed.