A's? I've taken apart laptop batteries before aren't those standard 18650's? They run at 3.7V.

@Windows7ge They are more commonly known as 18650 batteries. 

There is a comparison between the common A form factor and the laptop one, the laptop one is slightly shorter, but should fit in all compatible A sockets. 

Wikipedia has the information. 

https://en.m.wikipedia.org/wiki/List_of_battery_sizes

Here is the voltage, I don't think that they are fully charged though. 

I know all of them have some leeway. They often charge up to 4.1~4.2V even though 3.7V is the rating. Some cheapo LiPo chargers that I buy off Gearbest all charge up to 3.7V but not farther. If this slightly different model is 4V+ what do you use to charge them? Got a lab bench PSU?

@Windows7ge These batteries were from a gaming laptop, 12v battery.  It was 3 batteries in series with another 3 in parallel, so 6 in total.

I never charged them outside of the laptop port, but this should be safe.

It's a universal battery charger with all of the saftey features, and can charge multiple battery types, including lithium ion. 

I want to get a benchtop power supply, as well as an oscilloscope, but I have more important purchases to take care of first.