Any way to keep HEV from activating at 15% battery?

DudeM

I drive about 30 miles to work, and a fully charged battery can get me almost the entire trip, but one thing that bugs me is that the battery percentage never gets below 11 or 12% ever because the HEV activates automatically at 15%

So my question is this: Is there a way to change that so I can get that extra 10% EV and have the HEV activate at 5% instead? It seems like a waste of the 10% since it NEVER gets below that.

Thanks!