Hello ..... and a question about my batt charger

[Ellie_onVG]

I just signed on even though you all have been my mentors and encyclopedia since October 2010 when I
quit 2 pad/cigs and started vaping. So, Hello and thanks for all your help.

Someone with a multimeter just measured my battery charger (UltraFire Rapid for 3.2V/3.7v, Model WF-188)
and said the output reads 4.75v and he *thinks* that's too high.

I use this charger for two types of batteries, both are 3.7v:
UltraFire BRC 18650 3,000mah (Indulgence X)
AW ICR 123, 750mah (P16).

I'm wondering if I "ruined" it by charging the 3,000mah batts in it? It was supplied with the P16, for its 750mah batts, not these big ones. (I'm so totally clueless about this stuff, it's embarrassing.)

If you agree with the "meter reader" and say I should get rid of this charger and you happen to know of a good/better one, please let me know it. I'll use my Egos until then. Thank you so much!

Ellie_onVG

 

[Rocketman]

Open circuit battery voltage is not a trustworthy indication. Need to charge a cell, wait for the Green LED to come on, measure cell voltage while still in the charger, let it sit in the charger a little longer then measure voltage again. Continue this until the maximum voltage has been reached and starts to fall. Maximum charge voltage should not exceed 4.249999
4.20 is better.
Cell should drop a little after maximum has been reached.



You need your own meter.

 

[steliosak]

No its not to high.

It depends how he measured it and at what point in the charge cycle.

 

[Rocketman]

4.75 applied with the battery in the charger is a 'Bad Thing'.

 

[steliosak]

4.75 applied with the battery in the charger is a 'Bad Thing'.

You are correct.

As I said it depends how he measured it (OP did not specify).

If he measure the voltage that the charger produces (with no battery - just from the charger contacts) it could well be close to 5 volts.

If the battery is in the charger and at the end of its charge it should read aprox 4.2 Volts

 

[Rocketman]

gotcha, mis-communication.

 

[Ellie_onVG]

Thank you both. I got the multimeter back ... I looked up what "open circuit means" and hope I
correctly followed your directions.

The charger output with a battery charging: 3.87v

Battery in my hand: 3.77v

(None of my fully charged batts are over 4.1v.)

So I think I'm fine.

The initial reading of 4.75v occurred when the charger was empty

I will definitely get my own multimeter now. Thank you for taking the time to help me.

 

[Ellie_onVG]

Just for laughs ... I actually thought that the 4.7v my friend measured was
when the charger wasn't even plugged in. That's how much I know about these things

 

[Rocketman]

Ellie,
learned a little,
keep it going