Is IOS 11 still able to be Downgraded to IOS 10?

I have been satisfied with IOS 11 nearly enough but there is a few features missing. I loved IOS 10 and it suited my phone (iPhone 5s) a lot better as it was more capable of running and processing data on IOS 10 than it has been on IOS 11. the battery life has been significantly decreased when running IOS 11 and i have been dissapointed. 4 hour battery life has turned into 1 hour or less. Im womdering if there is still any signed copies of IOS 10 around, i have been searching for a long time but cannot find one anywhere. If anyone has any advice or knows anything please reply and let me know

Thanks,

Leo Tovell