Yes, that should be good enough. In my 7d holidays, the battery was enough for 2 people.

Have used it several times for 10-14 days (2x a day) on holiday without recharging.

We even took this toothbrush with us for our two-week holiday without having to charge it.
But charging is no big deal, with the case, which you usually have with you anyway, you can also charge the toothbrush.
Plug in the cable, charge, done.