I read the ARRL Rules but it is not clear to me. This will be my station: FT-891 Running at 100w Battery Power Solar Panel Public Park I am thinking I will be a "1B", but it says........."4.4. (Class B - Battery) One or two person portable: A Field Day station set up and operated by no more than two persons. All contacts must be made using an output power of 5 Watts or less and the power source must be something other than commercial mains or motor-driven generator. Other provisions are the same for Class A except it is not eligible for a GOTA or free VHF station. One and two person Class B - Battery entries will be listed separately."
You don't fit the definition for battery if your are running 100 watts. You would be "1B", but not battery. If you were a club station, you would be 1A.
On clarification, the A or B indicates if you are a club, or only a 1 or 2 person group. There is an additional term "battery" if your contacts are at 5 watts or less, and using battery power not charged by a motor driven generator. You would be 1B, since you are not a club.
You will also qualify for the 100 point bonus for "100% emergency power", and a 100 point bonus for "public location", and a 100 point bonus for "alternate power", if you make more than 5 contacts.