the way to go with your Eplus is to modify it to work with Lithium just like I did.
You would want to ask Rick to sell you really worn out, weak hub for cheaper.
Of course NMH electronics must communicate with display/controller on RS485 protocol for Eplus to power up.
It means Eplus NMH electronics must be incorporated into Lithium pack.
Quite simply electrically, read my posts?
Wait
I will attach schematics and pictures with instructions.