Low Voltage Cut off With Timer and Charger

So I have an application where I would like to have a low voltage cutoff and a timer that times how long it took to get to the cutoff voltage. As a bonus I would like to initiate a charge of the battery and not have the power turned on until it is reset. The recharging feature is not a must tho and may be too complex.

The point is to be able to burn test the batteries (have a burn tester already) and get the time that it took and after the test to charge the battery pack.

I have pretty good soldering skills and can usually understand technical logic. I have done some assembly projects in the past, however I have no real experience in circuit design.

Not sure if this is too much to ask but I would love it if some of you could assist me in this.

Some parameters that I can think of right away are; Charged voltage 24v. Cut off voltage 20V. burn tester draws 25-30A

Help?

Here is one I did for 24V lead-acid batteries in aircraft. This is a Hobbs Meter

So the expected burn time is usually under two hours. Not sure that the Hobbs Meter would be the correct scale for this application.

I guess that i would also need help understanding the diagram as well.

Any help is appreciated.