(ET) Rechargeable Push Mower Wanted

["Pestka, Dennis J" <Dennis Pestka TycoHealthcare com>]

I am looking to purchase a used rechargeable push mower for my daughter.
She is a biology/ecology major at the University of Missouri - Columbia.
The duplex she is renting has a small yard, and being an advocate to 
keeping
our environment pristine, 
would like to use a rechargeable electric mower/versus a gas model.
This can be running, or in need of repair.

Thanks;
Dennis

If no used units are available, I could use some opinions on which of the
newer models are the best.