Natasha Farrant, Natalie Sciver and Lauren Winfield, who made their international debuts against Pakistan last week, are included.
Katherine Brunt, Holly Colvin and Laura Marsh all return after injury, with the squad to be cut to 15 early next month.
"It is pleasing to see such healthy competition for places," said head of England women's cricket Clare Connor.
Women's Ashes Series
11-14 August: Only Test, Wormsley
20 August: 1st ODI, Lord's
23 August: 2nd ODI, Hove
25 August: 3rd ODI, Hove
27 August: 1st T20, Chelmsford
29 August: 2nd T20, Southampton
31 August: 3rd T20, Chester-le-Street
"Exciting young players from the academy have stepped up into the England squad in the recent internationals against Pakistan and have made an outstanding contribution on and off the pitch.
"This is an exciting time for all players, both the young and experienced, who will be hoping to have the honour of taking on Australia in the Ashes."
England won the one-day international series against Pakistan 2-0 before a 1-1 draw in a Twenty20 double-header.
The 2013 women's Ashes will be decided by playing all three formats.
The highest points total after one Test, three one-day internationals and three Twenty20s will win the series.
Six points will be awarded to the winners of the Test in Wormsley from 11-14 August, with each side receiving two points in the event of a draw. The limited-overs games which follow will see two points for a win.
The final two Twenty20 internationals, at Southampton and Chester-le-Street, will be played before the men's Twenty20 games between England and Australia.
Australia are the holders of the women's Ashes after winning a one-off Test match in Sydney in January 2011.
England squad to face Australia: Charlotte Edwards (Kent, capt), Tammy Beaumont (Kent), Arran Brindle (Sussex), Katherine Brunt (Yorkshire), Holly Colvin (Sussex), Georgia Elwiss (Sussex), Natasha Farrant (Kent), Lydia Greenway (Kent), Jenny Gunn (Nottinghamshire), Danielle Hazell (Yorkshire), Amy Jones (Warwickshire), Heather Knight (Berkshire), Laura Marsh (Kent), Natalie Sciver (Surrey), Anya Shrubsole (Somerset), Sarah Taylor (Sussex), Lauren Winfield (Yorkshire), Danielle Wyatt (Nottinghamshire).