CPU frequency always low

I'm running latest Sierra on my macbook pro i7 2ghz 2011, but I think slow so I try to see cpu frequency, and no matter what I run or do, frequency doesnt change! Always stay at 0,80 ghz

Important: this macbook dont have battery, I removed because inflated.

I have read some posts associating low frequency and no battery installed. This is correct ?

Any help, please?