EV Battery Pack using A123 7s3p Modules

[Sutho]

Have finally finished the assembly of the rear pack for our EV project. This pack consists of 12 x A123 7s3p connected in series for around 280Vnom. This will be connected in series to another 6 module pack in the front of the vehicle to give about 415Vnom.

The assembled pack slides into a carbon fiber/fiberglass box for support and weather protection. The aluminium rail frame hold the packs solidly together and allows it to be easily lifted in and out of the vehicle. So...if any of the modules give me grief, the pack can be lifted out and the module swapped out with relative ease in comparison to leaning into the vehicle and progressively disassembling the pack.

 

[voicecoils]

very nice!

What sort of bolts/ threaded inserts are being used on the aluminium bars? I can't quite see from the photos.

 

[Sutho]

What sort of bolts/ threaded inserts are being used on the aluminium bars? I can't quite see from the photos.

On the visible side have used M10 stainless Nutserts (also known as Rivnuts) with M10 stainless threaded rod which passes through each pair of modules. Tension is provided by Nyloc nuts on the opposite side.

 

[mrbigh]

NICE !!!! PROBABLY VERY HEAVY......

 

[texaspyro]

Nutserts

I bet that my friends' nutserts... he just had a tennis ball sized benign tumor removed from his testicles...

 

[Sutho]

NICE !!!! PROBABLY VERY HEAVY......

Heavy for a bike.....but not for a car. Weight is approx. 150kg. Same capacity in Headways would be at least 165kg + link bars + holders + frame.....and the Headways may not deliver enough current.

 

[peterperkins]

The Headways may not deliver enough current.

I don't think there is any doubt about that

Nice looking block 8)

 

[oatnet]

Very Cool pack. Look forward to seeing your installation of both packs!

Headways would not only have been considerably heavier, between the cylindrical format and the different chemistry, it would have taken up a lot more volume too. Of course the cylindrical format has a lot of surface area that provides better cooling - but headway cells also need a lot more cooling. :lol:

How many amps are you looking to pull from these packs?

-JD

 

[Sutho]

Headways would not only have been considerably heavier, between the cylindrical format and the different chemistry, it would have taken up a lot more volume too.

How many amps are you looking to pull from these packs?

Yes...volume was one of the other issues. I had the Headway packs designed into this project....but I just couldn't press the order button cos' they weren't what I was looking for. I was considering Kokam at nearly 4 times the price, then the loose A123 pouch cells.....then these modules came up. Exactly what I wanted, but unfortunately not all of them were in the condition I expected.....but I will eventually have at least 18 good modules.

Max battery draw should be about 380A. Max motor amps is 300A 3-phase.

The vehicle will be similar to one that will be released in the US next year. Not much chance of getting one here.....so I'm building my own. :wink:

Details and current state of the project are here: http://www.facebook.com/DMCEV
Or: http://www.evalbum.com/4238

 

[oatnet]

Very, very cool.

At 380a is only 6c+, a walk I'm the park for these cells. I look forward to seeing more!

-JD

 

[oatnet]

Ya know, with that much power, you are going to need some serious tires. I am thinking:
:lol:

 

[Sutho]

Ya know, with that much power, you are going to need some serious tires. I am thinking:
:lol:

Ha! I think you're onto something there. I wonder how the little input shaft on the transaxle will handle all that grip?

 

[texaspyro]

Do axial flux motors use flux capacitors?

 

[Sutho]

Do axial flux motors use flux capacitors?

Of course....where else would they get the name? :lol: