Quite some time ago, I produced a series of charge status charts for a variety of common lithium-ion battery voltages. They’ve become a fairly common link to help folks out on various Facebook groups who use these battery voltages in their ebikes.
I built them using Google Sheets, so they are not web pages, which I suppose has kept them from being widely linked in search engine results when people are looking at such things.
Here for the first time are direct links to the charts on a normal web page.
Remember, these charts show ballpark values that are as numerically correct as they can be. Individual cell characteristics will cause variation in the numbers here. Read the notes on the chart for a little more detail. Bottom line: cells degrade differently, but imperfect charts like this are still good baseline references. Use these and teach yourself how to read the voltage gauge on your display screen.
36 Volt (10S) Battery Charge Chart
The first link is to the lowest voltage: 36v. Generally this is the lowest voltage you will find on an ebike. Note that its called ’36 volt’ but really that is the ‘nominal’ value. A 36v battery is actually fully charged when it is at 42.0 volts.

48 Volt (13S) Battery Charge Chart
The next common size is 48v. These batteries are fully charged at 54.6 volts.

52 Volt (14S) Battery Charge Chart
The next battery voltage is 52v and very common. 52v batteries will work on systems designed for 48v, and why is easier to understand when you become aware that a ’48v’ battery really tops out at over 54 volts. A ’52v’ battery tops out at 58.8v, so it essentially lets you use a 48v system for a longer time at higher voltage levels that it is already designed to utilize.

60 Volt (16S) Battery Charge Chart
With a 100% charge voltage of 67.2 volts, when you have one of these you are more or less now using high voltage electricity

72v (20S) Battery Charge Chart