Full Electric Drive Conversion of Tri-Axle Coach 21700 or prismatic? Battery cycle Testers..?

[AkivaAld]

I think this is less likely to become a commercial reality due to regulations. On the PV input side, residential in the US is limited to 600 v
There are also battery voltage limits.

Most of the charge controller market is residential/mobile (not 1500 volt commercial) this means most manufacturers will be targeting a PV limit of 600 volts or whatever your local regulations allow.

There aren't many reasons (outside of an EV) to have a battery voltage in the 750 volt range. Even 230/240 vac has a peak to peak voltage of 370 volts(?) So that would be the upper end of any useful battery voltage with our going up to utility scale, where they will likely operate well above 750 volts.

Ah I see, here in Australia they just raised to 1000v PV input. for residential, I've been looking at the commercial stuff like battery chargers that are being attached directly to solar arrays in say shopping centres ect. none of them are yet to exceed 750v. Im certain with time there will be some new tech coming out that will be available, by the time im ready for the build im sure there will be something. For now I've set sights on 798v Top voltage of the 190S 26P packs.

appreciate the response

 

[AkivaAld]

Here is the Battery design, that will fit the compartment.
Each module will be 19S and 26P
70.3V nominal
130Ah Per module
9,139Wh capacity
Number of cells 494
Weight of cells 34,083G
Weight of Cell holder (printed in carbon PETG) 642.2G (added some green on there)
Total weight less nickel (yet to be calculated) 34,728G per module.

There will be 5 modules across the width of the bus (351.5Vnominal). Two strings will be needed to achieve nominal voltage of 703v nominal.
This was chosen due to the voltage range of the controller being at 800v. Absolute max 830v. This allows a top voltage at cell max 4.2*190=798V

The compartment has enough for 10 modules in height, with racking for Module stability, steel 100x50 crash exoskeleton frame to protect in an accident. I did Draw the frame up but fusion did not save to cloud properly... sad face
This means there will be 5 Full strings at 703v nominalm@130AH
Grand total capacity 703v@650AH = 456,950wh
Battery weight Sits at 1,736Kg without exoskeleton, racking, bms, nickel bus bars.

As I bring the information in I will share with you.

cheers to those who shared the products I didn't know existed, this has simplified the bms 1000 fold.

Here are the happy snaps from the day

 

[sunsurfer]

Did you build it?

Not yet. Current design is a separate turbine and compressor. I wanted to get away from needing an oiling system. Also, it solves the runaway problem with the compressor being over driven and creating a feed back loop.