Extra Battery, How to Integrate with 24kWh Traction Battery?

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IssacZachary said:
EVDRIVER said:
Push trailers have been around for many years, same for battery trailers etc.
Yes. And they work. The only ones trying to beat a dead horse are the nay-sayers why can't quite hit the horse because it's alive and well. I've known a couple individuals with perfectly fine working EV pusher trailers who's recommendation to me was, "Do it!"
EVDRIVER said:
Now that there are and will be many more low cost, longer range options... If you take those funds and lost time and get a cheap lease it would be better served.
Cheap lease? I've never leased. I was always under the impression that a lease was a waste of money. At least if you build a battery trailer the trailer and the car are still yours after a few years.

I don't recall saying they don't work they are just past their time for most people, many things work it's a question of making sense. Sure it may make perfect sense for someone who has the wrong EV for the job and wants to build and use a trailer and does not mind the associated headaches. Generators work and so do solar panels on the roof to a entertaining degree. In one year it will be interesting to see how many LEAF owners here use push trailers. That last thread with all the people arguing for them sure yielded a huge increase in their use in the last two years :roll: . Should you complete yours please add it to that thread with all the others. I would bet you that there are more trashed LEAFs that have commercially purchased pack extensions which made them inoperable then there are LEAFS with push trailers being used today, Two of those people I know now drive longer range EVs after abandoning their LEAFs and wish they had all that cash back.

FYI, leases often make more sense in cases when a vehicle has a high depreciation rate and/or you can deduct it as a business expense. Also works great for those want to upgrade to new and better vehicles more often. Nissan and other EV makers often have great lease deals in many states. In California you could get a net lease on a Spark at one point for under $100 a month after the CA rebate. The big picture is that in todays market the economics make far more sense for most people to get a longer range EV or hybrid then try to augment theirs. I also put a vote in for safely, what's that worth? Safely packaging a useful battery pack is not a low weight project and you would never get me to tow a trailer in a metropolitan area. :shock:
 
I don't know about anyone else, but part of my interest in this is just the sustainability of taking an otherwise perfectly good EV with a mechanical/electrical system that can probably survive another 100k miles and replacing/supplementing a low performing battery as tech improves. There's going to be ~300k Leafs on the market that will soon (~5-7 years) be abandoned as battery tech improves and EVs become mainstream. Would certainly be nice to be able to refurbish a Leaf with a modern range battery, especially those with ChaDeMo, which some modem long range offerings can't even support (Bolt still only does 50kW?)...
 
jkenny23 said:
I don't know about anyone else, but part of my interest in this is just the sustainability of taking an otherwise perfectly good EV with a mechanical/electrical system that can probably survive another 100k miles and replacing/supplementing a low performing battery as tech improves. There's going to be ~300k Leafs on the market that will soon (~5-7 years) be abandoned as battery tech improves and EVs become mainstream. Would certainly be nice to be able to refurbish a Leaf with a modern range battery, especially those with ChaDeMo, which some modem long range offerings can't even support (Bolt still only does 50kW?)...

Certainly makes sense to do that in the pack area and I'm sure there will be ways to do that. People swap Tesla packs from 60s to 100s.
 
EVDRIVER said:
IssacZachary said:
EVDRIVER said:
Push trailers have been around for many years, same for battery trailers etc.
Yes. And they work. The only ones trying to beat a dead horse are the nay-sayers why can't quite hit the horse because it's alive and well. I've known a couple individuals with perfectly fine working EV pusher trailers who's recommendation to me was, "Do it!"
EVDRIVER said:
Now that there are and will be many more low cost, longer range options... If you take those funds and lost time and get a cheap lease it would be better served.
Cheap lease? I've never leased. I was always under the impression that a lease was a waste of money. At least if you build a battery trailer the trailer and the car are still yours after a few years.

I don't recall saying they don't work they are just past their time for most people, many things work it's a question of making sense. Sure it may make perfect sense for someone who has the wrong EV for the job and wants to build and use a trailer and does not mind the associated headaches. Generators work and so do solar panels on the roof to a entertaining degree. In one year it will be interesting to see how many LEAF owners here use push trailers. That last thread with all the people arguing for them sure yielded a huge increase in their use in the last two years :roll: . Should you complete yours please add it to that thread with all the others. I would bet you that there are more trashed LEAFs that have commercially purchased pack extensions which made them inoperable then there are LEAFS with push trailers being used today, Two of those people I know now drive longer range EVs after abandoning their LEAFs and wish they had all that cash back.

FYI, leases often make more sense in cases when a vehicle has a high depreciation rate and/or you can deduct it as a business expense. Also works great for those want to upgrade to new and better vehicles more often. Nissan and other EV makers often have great lease deals in many states. In California you could get a net lease on a Spark at one point for under $100 a month after the CA rebate. The big picture is that in todays market the economics make far more sense for most people to get a longer range EV or hybrid then try to augment theirs. I also put a vote in for safely, what's that worth? Safely packaging a useful battery pack is not a low weight project and you would never get me to tow a trailer in a metropolitan area. :shock:
Don't get me wrong. I see your logic. And I'd like to say thanks because you've got me thinking on some other long distance solutions like perhaps getting a lease on a newer EV or trading my Leaf for a 30kWh one or going with some sort of PHEV solution. I'm just trying to see what would work best for me and likely for several others. Any idea what a lease on a 2018 Leaf or Tesla Model 3 would cost? From what I could find out about the Chevy Bolt a lease would be around $350 with a base 2017 Bolt without even any quick charging capability. $350 is almost double my Leaf's car payment and well out of my budget! Ouch!

Meanwhile, I'm hopefully going to have my 1972 VW Beetle up and running today for my long distance purposes. (Do you see any red flags as to safety, reliability, lack of common sense, etc.?) I can't help but wonder how long this will be my long distance solution. But it's what I can afford, so it'll have to work until I can figure something else out. The plan originally was to drive the Leaf and the Golf until used, longer range EV's become cheap and plentiful or an aftermarket longer-range battery become available.

But I keep coming back to the idea of integrating another battery to my Leaf via a trailer. The trailer would be for long distance highway purposes, not metropolitan driving where distances are shorter and charging stations much more abundant. Also the trailer could double as a power wall. I have designs for a solar panel that would provide up to 6kW of power, fit and fold up on top of the trailer, and cost less than $2,000. Yes, that's a lot of money, $3,000-$4,000 in batteries and $2,000 in solar panels. But $6,000 plus the $9,000 for my Leaf is still a whole lot cheaper than $30,000-$50,000 for the EV solutions on the market. Yes, I may be dreaming a far fetched fantasy.

But what if I sold my Bug for at least $6,000. Then what? Sell the Leaf too and take all that as a down payment on a new lease or car payment? Or build my battery trailer? Or buy a Prius?
 
IssacZachary said:
The plan originally was to drive the Leaf and the Golf until used, longer range EV's become cheap and plentiful or an aftermarket longer-range battery become available.


Makes sense. No idea on Tesla lease rates but I would think there will be lease deals on the LEAF or other EVs that are aggressive to compete with the large 3 sales figures. I would expect auto makers to have big incentives to get those buyers once the initial loyalty buyers have purchased.

LEAFs also don't end up being scrapped they in many cases go to auction and are shipped in very large numbers to Russia, Ukraine, the EU, etc. The export numbers are incredibly high for used LEAFs, one single private party alone ships many thousands of cars yearly. We are now turning the corner on range issues and I expect there will be downward pressure on prices if the market keeps headed in the same direction.
 
I just found the lease price of a 2017 Leaf. $225 dollars/month. Now that would be something I could handle! If Leaf gen 2 is that low I might make the jump from owner to leaser (or lease-a-nator or whatever I'd be called.)
 
IssacZachary said:
I just found the lease price of a 2017 Leaf. $225 dollars/month. Now that would be something I could handle! If Leaf gen 2 is that low I might make the jump from owner to leaser (or lease-a-nator or whatever I'd be called.)

Is there still a CO rebate as well?
 
EVDRIVER said:
IssacZachary said:
The plan originally was to drive the Leaf and the Golf until used, longer range EV's become cheap and plentiful or an aftermarket longer-range battery become available.


Makes sense. No idea on Tesla lease rates but I would think there will be lease deals on the LEAF or other EVs that are aggressive to compete with the large 3 sales figures. I would expect auto makers to have big incentives to get those buyers once the initial loyalty buyers have purchased.

LEAFs also don't end up being scrapped they in many cases go to auction and are shipped in very large numbers to Russia, Ukraine, the EU, etc. The export numbers are incredibly high for used LEAFs, one single private party alone ships many thousands of cars yearly. We are now turning the corner on range issues and I expect there will be downward pressure on prices if the market keeps headed in the same direction.

Yup, they get dumped here pretty much. I don't see much going to Eastern Europe at all; on the europe-wide car auction thingy we have here, almost all imported Leafs go to the big markets: Norway, UK, Netherlands, France.

The kicker though: whereas in the US you can expect to pay at most $8k for a well-used Leaf, here they sell for €12k used. More if it's not white and/or has low mileage. I do envy the US sometimes.
 
EVDRIVER said:
IssacZachary said:
I just found the lease price of a 2017 Leaf. $225 dollars/month. Now that would be something I could handle! If Leaf gen 2 is that low I might make the jump from owner to leaser (or lease-a-nator or whatever I'd be called.)

Is there still a CO rebate as well?

I think it's still available this year but greatly reduced from what it was when I bought my Leaf in 2016. Back then you got the precent off your Leaf what the kWh were, so I got a 24% rebate for buying a 24kWh Leaf. But it was to go down uy half, if I remember right, beginning January 2017, and then half again this month of January 2018. So a 30kWh Leaf may land me something like a 7% rebate. I'm not sure any of that applies to leases.
 
I got $5000 off from CO when I bought my 2017 Leaf. I doubt any of that would apply to a lease. A quick google search shows this same rebate ($5k) is extended to 2021 in CO. I never saw the money as it went straight from CO to the dealer and they just took it off the purchase price.
 
goldbrick said:
I got $5000 off from CO when I bought my 2017 Leaf. I doubt any of that would apply to a lease. A quick google search shows this same rebate ($5k) is extended to 2021 in CO. I never saw the money as it went straight from CO to the dealer and they just took it off the purchase price.
Ah. I see that the bill has changed on EV tax credits in Colorado. So it looks like yes, on a new EV one could get $5,000. I got about $4,000 on a used EV, but the bill no longer covers used EV's.
 
Getting back on topic, I wonder how this guy managed to get a Leaf to switch between two BMS's.

https://www.youtube.com/watch?v=Y9agY5Vbv8U

This would be ideal for a battery trailer. You could leave the battery trailer at a charging station, or put roughly 6kW (20' x 20') of fold out solar panels on it and leave it in some parking lot or something, and then come back to a fully charged battery trailer. You wouldn't need the two batteries to have the same voltage like has been done with some of these other experiments, hence they could be charged separately.
 
IssacZachary said:
Getting back on topic, I wonder how this guy managed to get a Leaf to switch between two BMS's.

https://www.youtube.com/watch?v=Y9agY5Vbv8U

This would be ideal for a battery trailer. You could leave the battery trailer at a charging station, or put roughly 6kW (20' x 20') of fold out solar panels on it and leave it in some parking lot or something, and then come back to a fully charged battery trailer. You wouldn't need the two batteries to have the same voltage like has been done with some of these other experiments, hence they could be charged separately.

I saw that a while back, it seemed pretty sparse on details. There's strangely an update as of 4 days ago, saying they can add 6 and 12 kWH also. I shot them an email asking for more details. It might be worth it to do one of the smaller range extensions just to see how they do it and see how scalable it is...
 
IssacZachary said:
Getting back on topic, I wonder how this guy managed to get a Leaf to switch between two BMS's.

https://www.youtube.com/watch?v=Y9agY5Vbv8U

This would be ideal for a battery trailer. You could leave the battery trailer at a charging station, or put roughly 6kW (20' x 20') of fold out solar panels on it and leave it in some parking lot or something, and then come back to a fully charged battery trailer. You wouldn't need the two batteries to have the same voltage like has been done with some of these other experiments, hence they could be charged separately.

Looks completely and utterly fake to me.
 
I'm quite skeptical of the smaller range extending options but for a full pack swap it seems pretty simple to me, just swap out the full BMS/contactor connector which he could have done manually when he put the camera down, and the 2 packs could be left in parallel since only one set of contactors would be active at any time.
 
jkenny23 said:
I'm quite skeptical of the smaller range extending options but for a full pack swap it seems pretty simple to me, just swap out the full BMS/contactor connector which he could have done manually when he put the camera down, and the 2 packs could be left in parallel since only one set of contactors would be active at any time.

I think you could leave both batteries in parallel and just use their contactors for changing between batteries. You could also possibly close both batteries' contactors and run both at the same time, provided both had the exact same level of charge and therefore voltage.

It would still be risky doing it that way though as seen here:

https://www.youtube.com/watch?v=6Zivzvh9Bx0&t=49s
[youtube]https://www.youtube.com/watch?v=6Zivzvh9Bx0&t=49s[/youtube]

But it looks like the problem resistor is in the inverter, not the battery itself. If you keep the contactors open in one traction battery there shouldn't be anything in there that could get fried that I know of. But there is a risk that there could be. It would be nice to find a diagram of how the traction batteries are wired just to make sure. Switching low voltage signals between batteries would be cheap and easy. But it would be nice to keep both connected to the main bus without any costly high power switching device. At most, a second set of contactors would be used to isolate the bus going to the second battery, especially if that battery were on a trailer.

Here's a video on the 12V signals:

https://www.youtube.com/watch?v=d0IozEyeGSk
 
Giant kick for this topic. I've finished up all the required wiring for the extender battery. This turned out to honestly be much easier than I expected, and considering the vague and scattered hints I had to work on so far I think I'll make a step-by-step walkthrough for the entire process of building an extender battery for the Leaf. Anyway, it's all in this video:

[youtube]https://www.youtube.com/watch?v=k3jaGtkyxvA[/youtube]

Next up, I will be putting a whole shitton of batteries in my trunk and drive around with it for a while to see how the installation holds up, how the contactors fare, if anything becomes hot, if fast charging works correctly, all that stuff. A company in the Netherlands has provided me with some VW GTE/eGolf battery modules to do my tests with, which makes my life a whole lot easier than having to weld a pack just for this test.

Then if everything is well and I got my custom BMS and control electronics in, I'll be making a permanent battery pack in a fireproof box underneath the car. This has already been designed in CAD, but building it is going to be a pretty labor-intensive process (considering I'm laminating it from fiberglass inside a big wooden laminating mold). So I don't expect that part of the story to come anytime soon.

But yeah, at the moment, it seems like I'll be driving around in a very long range Leaf in a week or so, maybe two!
 
mux said:
Giant kick for this topic. I've finished up all the required wiring for the extender battery. This turned out to honestly be much easier than I expected, and considering the vague and scattered hints I had to work on so far I think I'll make a step-by-step walkthrough for the entire process of building an extender battery for the Leaf. Anyway, it's all in this video:

https://www.youtube.com/watch?v=k3jaGtkyxvA

Next up, I will be putting a whole shitton of batteries in my trunk and drive around with it for a while to see how the installation holds up, how the contactors fare, if anything becomes hot, if fast charging works correctly, all that stuff. A company in the Netherlands has provided me with some VW GTE/eGolf battery modules to do my tests with, which makes my life a whole lot easier than having to weld a pack just for this test.

Then if everything is well and I got my custom BMS and control electronics in, I'll be making a permanent battery pack in a fireproof box underneath the car. This has already been designed in CAD, but building it is going to be a pretty labor-intensive process (considering I'm laminating it from fiberglass inside a big wooden laminating mold). So I don't expect that part of the story to come anytime soon.

But yeah, at the moment, it seems like I'll be driving around in a very long range Leaf in a week or so, maybe two!
Many thanks!!!

Keep us posted!!!

EDIT: And great video!!! You wired it exactly how I imagined I would do it.
 
Go mux! Go mux! Great work and video! I plan to do a similar extender although I was thinking I will make my battery pack not permanent and charged off-board in my shop. I want to have the pack in a suitcase (or two) and only connect up in the trunk in the infrequent event when I need the extra range. But if your permanent install looks good maybe I will change my mind.
 
mmmike said:
Go mux! Go mux! Great work and video! I plan to do a similar extender although I was thinking I will make my battery pack not permanent and charged off-board in my shop. I want to have the pack in a suitcase (or two) and only connect up in the trunk in the infrequent event when I need the extra range. But if your permanent install looks good maybe I will change my mind.

I'm seriously considering doing both. The permanent battery will increase my total useable capacity to around 35kWh, which is probably just a couple kWh shy of what we need to go on holiday and get there in one go. So for long trips, I think I'm going to try and package up these VW GTE batteries in some kind of easily removable container, cook up some safe high-current contacts behind one of the unexplained removable covers in the trunk and make a removable trunk battery. Those GTE batteries are 1.086kWh each at 12 series, so I need 8 of them to get to 96S, which is about 8.7kWh, a nice increment to the main battery.

Another option is to ALSO do a main battery swap with more modern cells. On a volume (85L) and weight (155kg) basis, you can fit about 40kWh inside the main battery shell if you use modern 18650s, or about 45kWh of 2170s. Well, a bit more because you can forego the compression stacks and use that volume for batteries. This, combined with the permanent extender, would make the 2011 Leaf a 60kWh car, without sacrificing trunk space. Certainly interesting, although I do NOT look forward to the labor involved in that. I think I'd only do that if I had a salvage pack available to me that I can just take my time swapping out the cells over the course of many weeks.

Regardless, the plans for everything will be published here, free of charge, for anyone to try out. If it all works out, I am pretty sure this is the way to go with Leaf extender batteries.
 
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