Charger question for the experts

[hyperloop]

Hi guys,

I love flashlights! But having no technical background at all and am trying to learn sloooooowlyy about all the different aspects of lights etc.

Here's my question:-

I have an Ultrafire WF-138 charger for my 14500s, can this charger be used for rechargable nimh AA cells??

pardon my ignorance here

 

[Niconical]

I have an Ultrafire WF-138 charger for my 14500s, can this charger be used for rechargable nimh AA cells??

Definately not.

 

[hyperloop]

that's what i thought but thanks for confirming this for a technically challenged individual.

 

[Niconical]

No problem. I should point out though that I am by no means a "charger expert", but I can answer this particular question with a very, very definate 'no'.

 

[matrixshaman]

Niconical is correct - the WF-138 puts out close to 5.0 volts for charging 3.6 volt batteries. Your NiMH are 1.2 volt batteries. I will say that charging voltage is not as critical in charging NiMH as charging current. Knowing that if you were in a real pinch and could constantly monitor your charge by removing the battery every couple minutes and checking it on a voltmeter as well as checking the temperature of the battery you might get away with using some Li-Ion chargers on a NiMH battery - but they are NOT designed to charge them and most will simply refuse to even try. This particular charger - the WF138 - has a built in sensing circuit that will not allow you to charge a battery with a voltage as low as NiMH so unless you know how to bypass that design it just won't work - period. You can get a lot of NiMH chargers cheap and even some of the better ones have had some exceptional pricing lately so don't take any chances - just get the right charger for your NiMH.

 

[lctorana]

And in practice, a cheap and nasty supermarket NiMH charger would do a better job anyway.