Some questions concerning a custom mod I plan to build that uses a non-standard battery

[Paul Siorai Waldorf]

Hey there ECF vets

So I have this idea and I'm trying to figure out just how feasible it might be to fabricate. Based on the information I have, it should do the trick quite nicely, but I am unsure, as I have never fabricated anything in my life. (I'll be looking to an experienced metal worker for the actual workmanship, but I thought I'd ask about it in here first to get some ideas about feasibility)

The idea started around my love for going into the sub-ohming and it's relative ability to be a bit unsafe. I started to look into better battery chemistry and stumbled across a company by the name of A123 that produces some pretty outstanding batteries. The one that caught my eye is the AHR32113M1Ultra-B( High Power Lithium Iron Phosphate 32113 Cylindrical Cells | A123 Systems Products ).

It boasts some pretty impressive stats:

Maximum Continuous Discharge Current - 200 amps
Maximum Pulse Current - 300 amps (10 seconds)
Peak Power at 10 seconds - 550 watts
Charging - Standard to 3.6 volts @ 6.75 amps
Charging - Fast charging to 3.5 @ 18 amps
Capacity - 4500 mAh
Cycle rates - Up to and including 10x that of normal lithium ion batteries (some reports are in the 10,000-20,000 range)

But it's huge. Physically, it's a rather large battery, 32mm in diameter, and 113mm long. Naturally, the size doesn't bother me, but right off the bat I knew I'd have to fabricate a mod for it.

There's other considerations too, as it's a LiFePo4 battery, so the 3.3v nominal, 3.6v maximum, means special charging, to be able to take advantage of the batteries ability to charge fast I'd probably have to make my own special charger, which I'm totally fine with.

So all well and good, but what are my questions?

What material should I use to fabricate for this? My fabricator thinks aluminum would do the trick the best, I've seen a couple of mods out there made out of it, so I'm inclined to agree, just no experience with em.

Would ditching the mechanical mod altogether and going with a 3D printed regulated mod be the best bet instead?

Has anyone ever used these 32113 batteries before in a mod? (I've seen their use rampant on motorcycles and what not, but never on vapes)

Is there anything else the experts feel I should be aware of before attempting this?

Thank you advance for taking a look, and I'll be patiently awaiting your reply.

 

[rolygate]

Well OK this is an interesting battery. It looks safe as it is an Li-FePO4 cell, which is the most stable of all the lithium types, but it has a low voltage output.

Assuming you can get 2 or 3 of them (and can afford it) as spares then you could build a 1-cell mechmod, either tubemod or boxmod format. This would have a nominal voltage around 3.2v and be fully charged at 3.6v. It has a lot of amp capacity, as these big Li-Fe cells do - but low voltage. It means that to get the equivalent of a sub-ohm coil of 0.5 ohm on an RBA on a regular mechmod, you'd need to go lower, maybe 0.4 or 0.3 ohm. If your mod is A1 quality, with a really good low-resistance circuit all the way through, it should be OK. But the slightest HR in there and the circuit resistance starts to look like the coil resistance and then you have a handwarmer.

The best use for this cell would be in a regulated mod running a buck/boost chip. Then you could get the circuit voltage up to 5, 6 or 7 volts or whatever it needs, with some serious capacity to back it up. However it's not as good as it looks for this, though, because you're going to burn more amps getting the voltage up as it's low to start with.

Maybe a 2-cell series regulator boxmod is the best use for this cell. It would be the size of a halfbrick. And then you have to be sure you can stack two of these cells because Li-Fe batts are sensitive to this - not surprising if one cell gets 100 amps pumped through it by the other.

If you have time and money to burn then this looks a fun project. If on the other hand you just need a homebuild that works from Day 1, this mega cell project could be a bad idea.