MickiO,
I think it is fantastic that you are learning to/ -and- using a multimeter to perform the MANDATORY checks to your batteries, now you need to educate yourself on a few key points.
If you EVER slip, or mistakenly touch the leads (bare metal part of the wires) together while in the process of measuring the voltage you will cause what is called a "short", this is pretty easy to recognise because it will produce a "spark" (and likely blemish the chrome on the lead ends). If this happens, (and please don't fool yourself and think "oh, that was just a little one") you seriously need to consider retiring that battery.
The second point is about MINIMUM voltage reading. These batteries have a requirement of a minimum voltage that is NEVER to go below 3.3 volts.
If either of these 2 events occur, it is standard practice to remove the offending battery from service. That means DO NOT put the battery back in a charger, or use it for vaping.
If your husband is handy enough to have a multimeter, he should be able to craft an insulator out of a straw or a chunk of a plastic pen body or something similair, that you can slip into the brass end of your batteries when testing them that will isolate the center terminal from the threaded part, so that you can avoid an inadvertant "short" at all times.
I'm taking the time to explain this because it is VERY important.
I find it unconscionable that this specific information is not supplied by the manufacturers, and prominently displayed for ALL buyers of E-cig equipment to see and adhere to.
You are doing the smart thing by learning more about your batteries and testing them. It is a safety issue.
I apologize for the long winded warnings , but if my efforts help even a single person to stay safe and avoid a possible injury and/or property damage, it is well worth the time.
If you doubt the gravity that is attributed to this issue, search on "lithium ion battery safety".
These points that I have outlined are not the only aspects of owning and using these batteries, but these two are essential.