The idea is to make USB charger which take it's power from rechargeable batteries so I can recharge them and use this portable charger any place to charge my mobile via USB cable.

so the electricity is not my domain but I thought this can be done as my knowledge that USB pc port give out 5 Voltes which is not huge amount
so I checked the internet and found some articles talking about this and people already did it.
so I take these articles and went to some one who work in electricity and ask him to build me this charger.
any way he make it but when I use it for my mobile HTC desire HD the mobile make the charge sign but the battery % goes down not up actually this happens when my mobile is on while I am changing so what I understand is this charges is not generating the required power
my info. is he puts 6 AAA rechargeable batteries each 1.2 and regulator to down the out volt to 5 and let and switch

so any one can help how to fix the problem ?

is it safe to remove the regulator so the charger generates more power?!!!

Please help and thanks all in advance,
is it safe to try to replace the 6 AAA batteries with 6 AA batteries as I think they will be generating more power? or this will be risky?!!