Am I using this multimeter correctly? Also question about battery

Got a new Klein m100 ranging dmm at homedepot, you can see my settings in the attached image below.

http://postimg.org/image/xmqtv6cg1/

Currently I am getting approx 3.6v readings from my sony vtc5 2600mah and 2x olight 3400mah. This makes sense since I"ve just used them for the first time.

My olight 3.6v 3400mah reads 3.6v, does that mean it is full(I thought approx 4.2 is full). I read that cells should be recharged when they drop to around 3.2-3.6v. If this is true it means that only .6v of the cell is actually being used before it had to be charged again, seems absurd.

Am I using this multimeter correctly?

Click to expand...

Yes your settings are correct.

My olight 3.6v 3400mah reads 3.6v, does that mean it is full(I thought approx 4.2 is full).

Click to expand...

No it is not full.
HKJ have made some good charts that indicates the remaining state of charge for various li-ions.
The tables are at the bottom of the linked page below

http://lygte-info.dk/info/BatteryChargePercent UK.html

I understand that everyone has a budget, and I'm not trying to be a multimeter snob, but when you are working with Li-ion of any flavor, can you TRUST your inexpensive meter?

In other words, unless you have your Klein checked for accuracy, can you be certain that it is not really 3.9v? But don't feel bad - I see guys with kilobuck lifepo4 marine house banks using the same meters to check voltages and it makes me cringe.

If all one wanted to do was to check voltage, and be able to trust something out of the box especially when working with li-ion, it would have to be the Fluke 114 as the most inexpensive of their series. Fortunately, at the 6v autorange, they are very accurate.

I just wonder how many projects here go awry when the ops follow the precise voltages spelled out in the faqs/wikis/warnings, and use a meter that can be way out of calibration.

Ok, soapbox over.

Another handy reference for you Simple guide to using a DMM for measurements.

WOW!! That is one fantastic thread started by HKJ. Golden!

The only thing I might add is that when it comes to measuring super low currents with a clamp-on ammeter, instead of using 1 loop, use 2 or more to get into a decent range if necessary, and of course divide the result by the turns of the wire.