Hi Pat, Troy offers very good advise, I use "LI-POs" But they have to be used with care,
With that in mind I would recommend you stay with "NIMHs" for the present,
I live in the UK and there is a dealer in the UK who will alter the connectors to suit your needs on request,
I feel sure that an American dealer would offer a similar service if you asked them.
Shaun..