battery sag sucks.

okey ,
i own this carbon gt super cool looking electric skateboard which has the worst battery sag i have ever seen in my entire usage of electric toys history,
even if there is no hill climb,
even the battery is fully charged,
the freaking sag will kick in after like 30 seconds of full throttle doesn't matter if i am in gt or fast mode,
this stupid battery sag will destroy the whole fun of it,
now it makes me wonder whats the point spending over 2 thousand dollars on a toy that has the shittest battery installed..
anyone wana shed some light on it or any solutions please,
thanks.

 

I am looking for someone in the USA that makes these.
I think the b sag is causing one of my motors to cut out when i hit the throttle fully.