Is it normal that my laptop lags when on battery while playing massive games?

My laptop plays games normally while charging but it lags terribly when on battery.
For example, playing COD Black Ops 2 when charging gives me 60 fps, but when in battery, it only gives me 10-20 fps.

Model: Lenovo ideapad Z10

Specs:
Core i7 4200MQ
4GB RAM
NVIDIA GT 740M
1TB HDD

Guest

I've never owned a gaming laptop but that doesn't sound normal to be losing frames. I would google this question to see if anyone has ever asked the same thing.

Anime Otaku