Before you solder up your led's IF you want to test them without soldering a resistor to it first. try this.... Your cordless phone battery is only 3 something volts... just stick the leeds in & BAM! a good one..
A LED tester that chances are you already have!!!


good luck... jh

 

Make your that battery isn't higher then 3.2v...
If it's higher, it will over drive the LED and it will damge them...
If it's little higher, then just power it for short period of time...
Like less then second....