Thank you so much MUX!!!! I so anticipate your work!!!! (I'm actually writing this as I charge from a charging station that's so far from my next destination I'm going to have to go 30mph down the highway for this next leg!)mux wrote:Mine are from the various electric/hybrid VWs - they all use the same or very, very similar modules. They are simply the easiest for me to get a hold of for this project, so I used them. They're not particularly easy to work with; I reverse engineered the BMS for the supplier, but this isn't open (I did this as paid work under NDA). So you'll have to add your own BMS to make this work. They're 12S modules, so you need 8 in series to get to 96S.
It's probably easier to go for Mitsubishi Outlander PHEV modules or GM Volt modules. They've been documented and are a bit easier to work with, especially the Volt modules. I believe those are 12 or 16S as well, so an easy multiple up to 96S. And people crank a kiloamp out of those as well, with very little wear.
On top of all of this you also need to add some BMS magic to make the GoM say useful things. I'm working on that, but it'll take about a month before that will be anywhere near done. This involves interrupting the EV-CAN from the main battery and modifying the GID packages to reflect the capacity in all batteries. Once I have that figured out, I'm making a bit tutorial on how to mod the '11-12 Leaf with extender packs.
For your money, the Chevy Volt batteries are the cheapest by far from what I've seen, as low as $130/kWH from eBay, and even lower if you search locally on salvage parts websites. Problem is they are pretty large. Smallest 96s configuration you could get is 3 16s2p groups (from a 2016 Volt or newer aka Gen 2) rewired for 32s1p, and that takes up most of the trunk volume, with ~9kWH capacity. Plus, rewiring them as series would be very challenging from what I've read. I'm probably going to go with a small modular pack approach using cells like the ones I posted earlier that can handle 2C charge rate. Smallest pack I would make is probably around 96s4p, with 8 12s4p modules wired in series.IssacZachary wrote: Thank you so much MUX!!!! I so anticipate your work!!!! (I'm actually writing this as I charge from a charging station that's so far from my next destination I'm going to have to go 30mph down the highway for this next leg!)
Also, while we're on the subject of where to get cells I'm looking at getting some of those Boston Power 5300's for about $25 per 100Wh used. I might get about $200 of them per month since that's about what my ICEV fuel bill is and with the better weather I can start to use just my Leaf so I won't be buying any fuel (I also get lots of free charging, but even paying for the electricity at home is very cheap compared to gasoline or diesel.) I'm trying to figure out a way to make a buildable battery, one that I can add in cells as I buy them so that I don't have to be bogged down with one big payment. If I can't I'll just put them on my credit card and pay them off as I go.
Another option I was also thinking of were these:
The only thing is you need $20,000 of them to make a 96s 74p 80kWh battery. Great for a battery trailer I guess. But otherwise I wonder if a guy could "cut them in half" and make a 37p 40kWh battery with them for half the price. Still, I'm short that kind of money though.
Are you not considering hybrids for the larger initial cost? Priuses are dead on reliable from what I've read (and my personal experience with a 2011 as my second car), and with electricity prices as crazy as they are for me in California, it's cheaper per mile to drive the Prius, though I get free charging at work so all my commuting is with the Leaf. Sadly longer range EVs are still very much in a higher tier price bracket, and look like they're going to stay that way for at least a decade.IssacZachary wrote:That's great info jkenny23!
I have to justify this before jumping into buying a bunch of expensive batteries and "hacking" into my car.
So far my Leaf is paid off. So I'm only paying for electricity, insurance, maintenance and any repairs. Using data from total cost to own calculators I should average out to around $3,179 per year or $264 per month for all car related expenditures with the Leaf by itself. However, I calculate that I'll actually paying closer to around $130 per month average including costs of original Michelin Energy Saver tires every 3 years as well as 12V batteries and windshield wipers and such. Of course I'm not calculating a new traction battery every so often in that figure.
Now if I sold my Leaf for as much as I possibly could and bought the most frugal car out there, like a used 2014 Mitsubishi Mirage I calculate I'd actually be paying as much as $200 more per month on average for the first 5 years! $200 in a year alone is $2,400 dollars! And by the time the 5 years are over I'd have saved as much as $12,000 by keeping the Leaf!!! So I guess what I'm saying is that I have $12,000 to invest in a better battery on the Leaf before it starts to become impractical. Or if I go by what online data says I could be paying in repairs and maintenance on the Leaf I still have as much as $6946 to spend on a better battery for the Leaf every 5 years.
So if I can spend that much every 5 years on battery technology then basically the Leaf would be cheaper from here on out than trading it in for even the most frugal ICEV available in the United States. Not that I have that $12,000 on hand right now, but it is a thought as to what makes the most sense. And that's not even comparing what I'd be spending if I traded in the Leaf for a Tesla, Bolt or newer Leaf!